EP2836177A1

EP2836177A1 - Appurtenances for reporting information regarding wound dressings

Info

Publication number: EP2836177A1
Application number: EP13775973.4A
Authority: EP
Inventors: Paul Duesterhoft; Nicholas DYKSTRA; Daniel Hawkins; Roderick A. Hyde; Jordin T. Kare; Mark K. Kuiper; Eric C. Leuthardt; Nels R. Peterson; Elizabeth L. SCHUBERT; Clarence T. Tegreene; Jr. Lowell L. Wood
Original assignee: Elwha LLC
Current assignee: Elwha LLC
Priority date: 2012-04-12
Filing date: 2013-04-10
Publication date: 2015-02-18
Also published as: EP2836269B1; EP2836177A4; EP2836269A1; EP2836269A4; WO2013155193A1; WO2013155199A1

Abstract

Appurtenances to wound dressings are described, which include: a substrate configured to mechanically or chemically attach to a wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; and a projection operably attached to the transmission unit, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid associated with a wound.

Description

APPURTENANCES FOR REPORTING

INFORMATION REGARDING WOUND

DRESSINGS

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related to and claims the benefit of the earliest available effective filing date(s) from the following listed application(s) (the "Related

Applications") (e.g., claims earliest available priority dates for other than provisional patent applications or claims benefits under 35 USC § 1 19(e) for provisional patent applications, for any and all parent, grandparent, great-grandparent, etc. applications of the Related Application(s)). All subject matter of the Related Applications and of any and all parent, grandparent, great-grandparent, etc. applications of the Related Applications, including any priority claims, is incorporated herein by reference to the extent such subject matter is not inconsistent herewith.

Related Applications:

For purposes of the USPTO extra-statutory requirements, the present application constitutes a continuation-in-part of United States Patent Application No. 13/445,174; entitled APPURTENANCES FOR REPORTING

INFORMATION REGARDING WOUND DRESSINGS; naming Paul Duesterhoft; Nicholas Dykstra; Daniel Hawkins; Roderick A. Hyde; Jordin T. Kare; Eric C. Leuthardt; Elizabeth L. Schubert; Clarence T. Tegreene; and Lowell L. Wood, Jr. as inventors; filed 12 April 2012; which is currently copending or is an application of which a currently co-pending application is entitled to the benefit of the filing date. For purposes of the USPTO extra-statutory requirements; the present application constitutes a continuation-in-part of United States Patent Application No. 13/491,677; entitled DORMANT TO ACTIVE APPURTENANCES FOR REPORTING INFORMATION REGARDING WOUND DRESSINGS;

naming Paul Duesterhoft; Nicholas Dykstra; Daniel Hawkins; Roderick A. Hyde; Jordin T. Kare; Mark K. Kuiper; Eric C. Leuthardt; Nels R. Peterson; Elizabeth L. Schubert; Clarence T. Tegreene; and Lowell L. Wood, Jr. as inventors; filed 08 June 2012; which is currently co-pending or is an application of which a currently co-pending application is entitled to the benefit of the filing date.

For purposes of the USPTO extra-statutory requirements; the present application constitutes a continuation-in-part of United States Patent Application No. 13/795,667; entitled APPURTENANCES TO CAVITY WOUND

DRESSINGS; naming Paul Duesterhoft; Nicholas Dykstra; Daniel Hawkins; Roderick A. Hyde; Jordin T. Kare; Eric C. Leuthardt; Elizabeth L. Schubert; Clarence T. Tegreene; and Lowell L. Wood, Jr. as inventors; filed 12 March 2013; which is currently co-pending or is an application of which a currently copending application is entitled to the benefit of the filing date.

For purposes of the USPTO extra-statutory requirements; the present application constitutes a continuation-in-part of United States Patent Application No. 13/445,220; entitled COMPUTATIONAL METHODS AND SYSTESM FOR REPORTING INFORMATION REGARDING APPURTENANCES TO WOUND DRESSINGS; naming Paul Duesterhoft; Nicholas Dykstra; Daniel Hawkins; Roderick A. Hyde; Jordin T. Kare; Eric C. Leuthardt; Elizabeth L. Schubert; Clarence T. Tegreene; and Lowell L. Wood, Jr. as inventors; filed 12 April 2012; which is currently co-pending or is an application of which a currently co-pending application is entitled to the benefit of the filing date.

The United States Patent Office (USPTO) has published a notice to the effect that the USPTO's computer programs require that patent applicants reference both a serial number and indicate whether an application is a continuation, continuation-in-part, or divisional of a parent application. Stephen G. Kunin, Benefit of Prior-Filed Application, USPTO Official Gazette March 18, 2003. The present Applicant Entity (hereinafter "Applicant") has provided above a specific reference to the application(s) from which priority is being claimed as recited by statute. Applicant understands that the statute is unambiguous in its specific reference language and does not require either a serial number or any characterization, such as "continuation" or "continuation-in-part," for claiming priority to U.S. patent applications. Notwithstanding the foregoing, Applicant understands that the USPTO's computer programs have certain data entry requirements, and hence Applicant has provided designation(s) of a relationship between the present application and its parent application(s) as set forth above, but expressly points out that such designation(s) are not to be construed in any way as any type of commentary and/or admission as to whether or not the present application contains any new matter in addition to the matter of its parent application(s).

SUMMARY

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: a substrate configured to mechanically or chemically attach to a wound dressing, a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; and a projection operably attached to the transmission unit, the projection of a size and shape to extend into an interior region of the wound dressing.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: a substrate configured to attach to a wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry; a selectively actuatable switch operably connected to the transmission unit; a projection operably attached to the substrate, the projection of a size and shape to extend into an interior region of a wound dressing; and one or more sensors integral to the projection and operably connected to the selectively actuatable switch.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: one or more sensors; a processor operably attached to the one or more sensors; at least one transmitter unit operably attached to the processor; and an enclosure of a height and width to fit substantially within an interior region of a wound dressing.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: a sensing unit including one or more sensors, the sensors positioned substantially within an enclosure of a height and width to fit substantially within an interior region of a wound dressing; a transmission unit including a processor and at least one transmitter unit operably attached to the processor; and a connector between the sensing unit and the transmission unit, the connector configured to convey signals between the one or more sensors and the transmission unit.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: a substrate; a passive radio frequency identification (RFID) unit attached to the substrate; and a substantially hollow projection operably attached to the substrate, the projection including a first end and a second end, the first end of a size and shape to extend within a wound dressing, the second end extending into the passive radio frequency identification unit. In addition to the foregoing, other aspects of an appurtenance to a wound dressing are described in the claims, drawings, and text forming a part of the present disclosure.

In one aspect, a device includes, but is not limited to: a wound dressing; a transmission unit irreversibly attached to the wound dressing, the transmission unit including circuitry and at least one antenna; a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending within an interior region of the wound dressing. In one aspect, an article of manufacture includes, but is not limited to: a wound dressing; a substrate attached to an external surface of the wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending through the external surface of the wound dressing. In addition to the foregoing, other device aspects are described in the claims, drawings, and text forming a part of the present disclosure.

In one aspect, a device for attaching an appurtenance to a wound dressing includes, but is not limited to: a base plate; a handle attached to the base plate; a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing; a handle attached to the holder region; and a pivot between the handle attached to the base plate and the handle attached to the holder region. In addition to the foregoing, other aspects of a device for attaching an appurtenance to a wound dressing are described in the claims, drawings, and text forming a part of the present disclosure.

In one aspect, a method of attaching an appurtenance to a wound dressing includes, but is not limited to: placing an appurtenance for a wound dressing in contact with an outer surface of the wound dressing; and providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing. In addition to the foregoing, other method aspects are described in the claims, drawings, and text forming a part of the present disclosure.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: a substrate configured to attach to a wound dressing; a fluid- activated voltaic cell attached to the substrate; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to current generated by the fluid-activated voltaic cell; and a projection operably attached to the fluid- activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow fluid to flow from the interior region of the wound dressing into the enclosure; a fluid- activated voltaic cell attached to one or more of the at least one aperture; and a transmission unit attached to an internal surface of the enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid- activated voltaic cell.

In one aspect, an appurtenance to a wound dressing includes, but is not limited to: an appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow fluid flow from an interior region of a wound dressing into the appurtenance; a fluid- activated voltaic cell including an internal chamber, the internal chamber attached to the conduit; and a radio frequency identification (RFID) unit attached to the fluid- activated voltaic cell and configured to operate in response to current generated by the fluid- activated voltaic cell.

In one aspect, a method of monitoring a wound includes, but is not limited to: conveying fluid from an interior region of a wound dressing to an appurtenance of the wound dressing; placing the fluid adjacent to a first electrode and a second electrode of a fluid- activated voltaic cell integral to the appurtenance; and utilizing current received from the fluid-activated voltaic cell directly to send a wireless signal beyond the appurtenance.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound; and a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes: a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg; and the plurality of sensor units in the aggregate of a size and mass to allow for medical use with the porous dressing material at the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures; and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to associate with a cavity wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry; a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch. In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to fit

substantially within a cavity wound in association with a wound dressing; and a plurality of sensor units attached to the substrate, each of the sensor units including a detector and an indicator, wherein the indicator includes a passive radio frequency identification (RFID) unit.

A system for monitoring a cavity wound medical dressing includes at least one appurtenance to a cavity wound dressing and at least one external device. For example, some embodiments include an appurtenance to a cavity wound dressing, the appurtenance including a substrate and a plurality of sensor units, wherein each of the sensor units include an indicator configured to respond to a specific external signal; and an external device configured to transmit the specific external signal and detect the response of the indicator included with each of the plurality of sensor units. Some embodiments include a local unit configured to transmit signals to an appurtenance and receive signals from the appurtenance. Some embodiments include at least one central assembly configured to communicate with at least one local device.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic of an appurtenance to a wound dressing in use with a wound. FIG. 2 A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing.

FIG. 2B is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 3 is a schematic of an appurtenance to a wound dressing in use with a wound. FIG. 4 is a schematic of an appurtenance to a wound dressing in use with a wound. FIG. 5A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing.

FIG. 5B is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 6 is a schematic of an appurtenance to a wound dressing.

FIG. 7 is a schematic of an appurtenance to a wound dressing.

FIG. 8A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing.

FIG. 8B is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 9 A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing. FIG. 9B is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 10 A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing.

FIG. 10B is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 11A is a schematic of an appurtenance to a wound dressing prior to attachment to a wound dressing.

FIG. 1 IB is a schematic of an appurtenance to a wound dressing after attachment to a wound dressing.

FIG. 12 is a schematic of an appurtenance to a wound dressing.

FIG. 13 is a schematic of an appurtenance to a wound dressing

FIG. 14 is a schematic of an appurtenance to a wound dressing

FIG. 15 is a schematic of an appurtenance to a wound dressing

FIG. 16 is a schematic of an appurtenance to a wound dressing

FIG. 17 is a schematic of an appurtenance to a wound dressing

FIG. 18 is a schematic of an appurtenance to a wound dressing

local unit.

FIG. 19 is a schematic of an appurtenance to a wound dressing in communication with a local unit.

FIG. 20 is a schematic of an appurtenance to a wound dressing in communication with a local unit and a central assembly.

FIG. 21 is a schematic of an appurtenance to a wound dressing in communication with a local unit, a central assembly and a remote device.

FIG. 22 is a schematic of layers of a wound dressing and potential placement of appurtenances relative to the layers.

FIG. 23 is a schematic of an appurtenance to a wound dressing.

FIG. 24 is a schematic of an appurtenance to a wound dressing.

FIG. 25 is a schematic of an appurtenance to a wound dressing.

FIG. 26 is a schematic of an appurtenance to a wound dressing.

FIG. 27 is a schematic of an appurtenance to a wound dressing.

FIG. 28 is a schematic of an appurtenance to a wound dressing.

FIG. 29 is a schematic of an appurtenance to a wound dressing. FIG. 30 is an illustration of an appurtenance to a wound dressing.

FIG. 31 is a depiction of a local unit.

FIG. 32A illustrates a wound region on a human body part.

FIG. 32B depicts, in cross-section, a cavity wound in the wound region shown in Fig. 1A.

FIG. 33A shows an appurtenance to a cavity wound dressing.

FIG. 33B illustrates, in cross-section, an appurtenance in use in a cavity wound. FIG. 34 shows, in cross-section, an appurtenance in use in a cavity wound with a wound dressing.

FIG. 35A depicts an appurtenance to a cavity wound dressing.

FIG. 35B illustrates, in cross-section, an appurtenance in use in a cavity wound.

FIG. 36 shows, in cross-section, an appurtenance in use in a cavity wound with a wound dressing.

FIG. 37 depicts an appurtenance to a cavity wound dressing.

FIG. 38 illustrates, in cross-section, an appurtenance in use in a cavity wound.

FIG. 39 depicts an appurtenance after removal from a cavity wound.

FIG. 40 shows a cross-section view through an appurtenance.

FIG. 41 illustrates a sensor unit.

FIG. 42 depicts a sensor unit.

FIG. 43 shows a sensor unit.

FIG. 44 illustrates an appurtenance to a cavity wound dressing.

FIG. 45 depicts, in cross-section, an appurtenance.

FIG. 46 shows, in cross-section, an appurtenance in use in a cavity wound with a wound dressing.

FIG. 47A illustrates a wound region on a human body part.

FIG. 47B depicts, in cross-section, a cavity wound with an appurtenance and a wound dressing in the wound region shown in Fig. 16A.

FIG. 48 illustrates an appurtenance to a cavity wound dressing in communication with a local unit.

FIG. 49 depicts aspects of a local unit.

FIG. 50 shows aspects of a system including an appurtenance, a local unit and a central assembly.

FIG. 51 illustrates a system for monitoring cavity wound dressings. DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description and drawings are not meant to be limiting. Other embodiments can be utilized, and other changes can be made, without departing from the spirit or scope of the subject matter presented here.

The use of the same symbols in different drawings typically indicates similar or identical items.

With reference now to Figure 1, shown is an example of an appurtenance 120 to a wound dressing 115, used on a wound 100, which can serve as a context for introducing one or more processes and/or devices described herein. As shown in Figure 1, a body part 110, such as a leg, includes a wound 100. A wound dressing 115, selected by a medical caregiver as appropriate in size, shape and type for the wound 100, has an appurtenance 120 attached to generate an appurtenance affixed to a wound dressing combination unit, 125. The appurtenance 120 can be attached to the wound dressing 115 with a mechanical attachment (see, e.g. Figs. 11 A and 1 IB). For example, a mechanical attachment can include attachments shaped like prongs, barbs, bristles, spikes, or spurs. The appurtenance 120 can be attached to the wound dressing 115 with a chemical attachment, such as a pressure-sensitive adhesive, a contact adhesive, or a quick-drying adhesive. The appurtenance 120 is a separate and distinct element that can be attached to the wound dressing 115 in a manner sufficient for operation during the use of a specific wound dressing 115. The appurtenance 120 is a separate and distinct element that can be attached to the wound dressing 1 15 in an irreversible manner. For example, the appurtenance- wound dressing combination unit, 125, can be disposed of after use. Immediate disposal after use can be desirable to minimize biosafety, contamination and biohazard issues. The appurtenance 120 is a separate and distinct element that can be attached to the wound dressing 115 in a reversible manner. For example, the appurtenance-wound dressing combination unit, 125, can be taken apart into its component wound dressing 115 and appurtenance 120 after use. For example, the appurtenance 120 can be configured for reuse with a new wound dressing 115. The appurtenance 120 can be configured for reuse after treatment, such as after disinfection, cleaning, or sterilization. An appurtenance 120 to a wound dressing 115 can be reused, for example, on a succession of wound dressings 115 used by the same patient.

The appurtenance 120 is configured for functional use only when attached to the wound dressing 115. The appurtenance 120 is of a size, shape and material for functional use only when attached to the wound dressing 115. The appurtenance 120 is configured to operate in conjunction with the wound dressing 115. The appurtenance 120 is appended to the wound dressing 115 to generate an appurtenance-wound dressing combination unit 125, as illustrated in the lower right region of Figure 1. The appurtenance 120 includes at least one region that projects into the structure of the wound dressing 115. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to be entirely enclosed within the structure of the wound dressing 115. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to project through the wound dressing 115, for example to a region adjacent to a wound. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to project through the wound dressing 115, for example to a wound bed region. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to project through a portion of the wound dressing 115, for example to a sinus or cavity of the wound bed. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to project through a portion of the wound dressing 115, for example to a dressing placed within a sinus or cavity of the wound bed. In some embodiments, the region that projects into the structure of the wound dressing 115 is of a size and shape to project through a portion of the wound dressing 115, for example to a layer placed adjacent to the wound surface. The appurtenance 120 affixed to the wound dressing 1 15 forms an integrated unit of the appurtenance and the wound dressing as a combination unit 125 (see, e.g. Figs. 2, 5, and 7-11). In some embodiments, the wound dressing- appurtenance combination unit 125 is not readily separable, and the individual wound dressing 115 and appurtenance 120 are not suitable for separation and individual use after they have been joined together. As illustrated in the lower portion of Figure 1, once the appurtenance 120 is affixed to the wound dressing 115, the appurtenance and the wound dressing together as a combination unit 125 are used to cover and monitor the wound 100.

In some aspects, an appurtenance 120 to a wound dressing 115 is configured to monitor one or more aspects of a wound 100. An appurtenance 120 to a wound dressing 115 can be used by a caregiver or a patient to monitor a wound 100. In some aspects, an appurtenance 120 to a wound dressing 115 is configured to monitor one or more aspects of a wound dressing 115. An appurtenance 120 to a wound dressing 115 can be used by a caregiver, including a patient, to monitor a wound dressing 115. An appurtenance 120 to a wound dressing 115 is configured to allow a user, such as a caregiver or patient, to monitor a wound dressing and the adjacent wound without disturbing the wound dressing 115 such as through removing the dressing 115 from the patient's wound 100. This approach, inter alia, improves comfort to the patient, reduces the chance of accidental infection in or contamination from uncovered wounds, and minimizes time requirements in wound care. As described further below, in some aspects, an appurtenance 120 to a wound dressing 115 includes a transmitter that sends a signal to a device used by a caregiver or patient to monitor the wound dressing from the same room as the patient. As also described further below, in some aspects, an appurtenance 120 to a wound dressing 115 includes a transmitter that sends a signal to a device used by a caregiver remotely, such as through a pager, remote computing device, cell phone, or dedicated remote signaling device. The signal transmitter sends a signal containing information associated a wound and/or adjacent wound dressing such that a caregiver is able to receive, directly or indirectly, information relating to monitoring a wound and adjacent wound dressing at a distance from the patient, without disturbing the patient and with minimal time spent analyzing the wound 100 or wound dressing 115.

As described further below, in some aspects, an appurtenance 120 to a wound dressing 115 is part of a system configured to automatically process and save information relating to an appurtenance 120 and the related wound dressing 115 to a medical record system, such as a medical records database. This automatic process reduces the potential for accidental loss or error in data entry regarding wound care, and reduces the time required by a caregiver in data entry into a record.

The wound dressing with the affixed appurtenance combination unit 125 is used to cover the wound 100 on the body part 110. The wound dressing with the affixed appurtenance combination unit 125 can be secured to the body part 110 in a routine manner for the type of wound dressing 115 generally, such as through adhesive integral to the wound dressing 115 or with additional adhesive, wrappings, tapes or glues as generally applicable to the type of wound dressing 115 utilized in a given medical situation.

Although not illustrated in Figure 1 , the wound dressing with the affixed appurtenance combination unit 125 can similarly be removed using standard removal procedures, such as with gentle pressure, gentle pulling, unwrapping, allowing it to loosen over time, or biocompatible solvents. The appurtenances 120 described herein can be single-use and disposable along with the affixed wound dressing 115. In some embodiments, the appurtenances 120 described herein can be removed from a first wound dressing and then reconditioned, such as through cleaning or sterilization, and reused with a second wound dressing. In some embodiments, an appurtenance 120 can be reused for multiple wound dressings used on a single wound from a patient. The appurtenances 120 described herein are generally intended to be operable for the period of time a given wound dressing 115 is in use under standard conditions and time periods. After the wound dressing with the irreversibly affixed appurtenance combination unit, 125 is removed from the body part 110, it can be disposed of as a unit with routine disposal methods.

It is envisioned that the appurtenances 120 described herein will be utilized while affixed to wound dressings 115 over wounds 100 of a variety of types, and operable to assist in the monitoring of wounds of a variety of types. For example, appurtenances 120 can be used in conjunction with wound dressings 115 to assist in monitoring acute wounds, such as those resulting from accidental injury or surgery. For example, appurtenances 120 can be used in conjunction with wound dressings 115 to assist in monitoring wounds closed by primary intention. For example, the appurtenances 120 can be used to assist in monitoring wound dressings over surgical wounds, such as incisions and surgical stitches. For example, the appurtenances 120 can be used to assist in monitoring wound dressings over acute wounds from injury, such as burn injuries, lacerations, or penetrating wounds. For example, appurtenances 120 can be used in conjunction with wound dressings 115 to assist in monitoring wounds closed by secondary intention. The appurtenances 120 can also be used to assist in monitoring wound dressings over chronic wounds, such as those arising from chronic medical conditions and situations. For example, the appurtenances can be used to monitor the status of wound dressings covering venous leg ulcers, diabetic foot ulcers, pressure ulcers or arterial ulcers. See: "Advances in Wound Healing Techniques," publication Dl 1A, Frost and Sullivan, 2008; "An Overview of Ulceration Wounds," Publication M4BB-54, Frost and Sullivan 2009; and "US Advanced Wound Care Market," Publication N71A-54, Frost and Sullivan 2010, which are each incorporated herein by reference. The appurtenances 120 described herein can be useful in conjunction with an affixed wound dressing as a combination unit 125 to monitor potential problems with a wound, such as excessive bleeding or other fluid formation that would be present in the wound dressing, or the presence of conditions in the dressing that indicate infection in an adjacent wound. See: Collier, "Recognition and Management of Wound Infections," World Wide Wounds, pages 1-9, (January 2004); and Gray, "Assessment, Diagnosis and Treatment of Infection," Wounds UK, vol. 7, no. 2, supplement, (2011), which are each incorporated herein by reference. For example, some types of wound discharge can indicate infection. See, for example, Cutting and Harding, "Criteria for Identifying Wound Infection," Journal of Wound Care, vol. 3, no. 4, 198-201 (1994), which is incorporated herein by reference. The appurtenances 120 as part of combination units 125 and related systems described herein can be used in conjunction with readily available types of wound dressings to monitor aspects of the affixed wound dressing, including parameters that indicate that a person should physically examine the wound dressing, such as excessive wetness, dryness, an elapsed period of time, or the presence of specific factors detected by one or more sensors of the appurtenance. The appurtenances 120 as well as related systems described herein can be used in conjunction with readily available types of wound dressings to monitor aspects of the affixed wound dressing, including indications that the wound dressing should be changed {i.e. excessively wet, dry, or soiled).

The appurtenances described herein include transmission units configured to transmit signals, and thereby report information regarding the status of the affixed wound dressing or wound, to associated systems. The resulting information reporting can be used, in some embodiments, to supplement the medical record for a patient in an automated system and automatic process. The resulting information reporting can be used, in some embodiments, to automatically notify a caregiver that the status of the wound dressing has altered, indicating that a person should physically inspect the wound dressing.

As used herein, a caregiver includes at least one of a patient, a caregiver, and medical personnel. A caregiver can utilize some embodiments of the appurtenances and related systems described herein in relation with multiple types of wound dressings. Appurtenances can be fabricated in shapes and sizes to conform to a variety of standard wound dressing sizes, shapes and types. Appurtenances can be fabricated with, for example, transmission units, antennas and sensors appropriate for use with a variety of wound dressings. Appurtenances can be fabricated with, for example, transmission units, antennas and sensors appropriate for different medical situations and monitoring requirements. Appurtenances can be fabricated with, for example, one or more projections of a size, shape and material appropriate for use with a variety of wound dressings. While it is envisioned that every appurtenance will not be appropriate for use with every wound dressing (for example due to size, shape or material compatibility), a given appurtenance is expected to be suitable for use with a range of potential wound dressings. For example, a given appurtenance of a specific size, shape and fabrication, including type of transmission unit, sensors, and projection(s), should be suitable for use with a variety of wound dressings of conforming sizes, shapes and types. Generally, any specific appurtenance embodiment is not expected to only conform to use with a unique wound dressing of a specific size, shape and type. Instead, it is expected that a specific appurtenance embodiment will be suitable for use with a range of wound dressings.

Similarly, it is expected that a specific appurtenance embodiment will be suitable for use with a range of wound and wound dressing monitoring requirements.

In the attached drawings, an appurtenance 120 is generally illustrated as affixed to an outer surface of a wound dressing 115, for example an outer surface distal to a surface of the body part 110 adjacent to the wound 100. However, in some embodiments, an appurtenance 120 can be configured to attach to one or more surfaces of a wound dressing 115 adjacent to a surface of the body part 110 adjacent to the wound 100. For example, in embodiments wherein an appurtenance 120 is configured to be attached to a wound dressing 115 of a substantially rectangular, ovoid, or raised conformation, an appurtenance 120 can be configured to be attached to a side surface of the wound dressing 115. For example, in embodiments wherein an appurtenance 120 is configured to be attached to a wound dressing 115 with an unusually strong or thick outer cover layer, the appurtenance 120 can be configured to attach to an underside of the wound dressing 115. In some embodiments, an appurtenance is configured to attach to a surface of a wound dressing 115 in contact with the surface of the body part 110.

For example, the appurtenances described herein can be configured to be affixed to a dry gauze dressing, which can or can not include an outer cover layer. For example, the appurtenances described herein can be configured to be attached to a dry silicone or other solid foam dressing, which can or can not include an outer cover layer. For example, the appurtenances described herein can be configured to be affixed to a wound dressing used to close a small or thin wound or surgical incision, such as a butterfly dressing (e.g.

SteriStrip™ adhesive strips, available from Nexcare™, part of 3M Corporation). For example, appurtenances such as those described herein can be configured to be affixed to a dressing configured to maintain moisture or other materials adjacent to the wound surface. For example, appurtenances such as those described herein can be configured to be used with hydrogel wound dressings, for example Aquaflo™ Hydrogel Wound Dressing by Kendall Corporation, or Elasto-Gel™ Hydrogel Occlusive Dressing by Southwest Technologies. For example, appurtenances such as those described herein can be affixed to wound dressings including hydrocolloids, for example DuoDERM CGF Sterile

Hydrocolloid Dressing manufactured by DuoDERM Corporation. For example, appurtenances such as those described herein can be configured to be used with wound dressings containing one or more medicinal agents, such as antibiotics. For example, appurtenances such as those described herein can be used with wound dressings impregnated with PHMB (Polyhexamethylene Biguanide), such as Telfa™ A.M.D.

antimicrobial wound dressings, manufactured by Kendall Corporation. For example, appurtenances such as those described herein can be configured to be used with wound dressings including ionic silver, such as Maxorb™ Extra Ag wound dressings

manufactured by Medline Corporation. Appurtenances such as those described herein can be configured to be affixed to wound dressings over wounds wherein the tissue of the wound is being directly monitored using other devices, for example as described in US Patent No. 6,963,772 to Bloom et al, titled "User-retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference.

Appurtenances such as those described herein can be configured to be affixed to wound dressings over wounds wherein the patient is being directly monitored using other devices, for example as described in US Patent No. 7,030,764 to Smith and Cooper, titled

"Apparatus and Method for Reducing the Risk of Decubitus Ulcers;" US Patent No.

7,297,1 12 to Zhou et al, titled "Embedded Bio-Sensor System;" US Patent Nos.

7,372,780, 8,014,234 and 7,813,226 to Braunberger, titled "Timing System and Device and Method for Making the Same;" US Patent No. 7,666, 151 to Sullivan et al, titled "Devices and Methods for Passive Patient Monitoring;" US Patent No. 7,703,334 to Cochran, titled "Bandage Type Sensor Arrangement and Carrier Assembly Therefore, and Method of Manufacture;" and International Patent Publication No. WO 2005/009328 to Nikolic, titled "ABT- Anti-Bedsore Timer," which are each incorporated herein by reference. Appurtenances such as those described herein can also be used in conjunction with a system to monitor assets within a health care facility, for example as described in US Patent Application No. 2007/0247316 to Wildman et al, titled "Article Locating and Tracking Apparatus and Method," which is incorporated herein by reference.

Wound dressings 115 such as those described herein are generally used for a relatively short period of time, on the order of hours or days, and then removed for disposal. Similarly, a wound dressing with an affixed appurtenance combination unit 125 should be configured for use over the course of hours or days and then removed and disposed of using standard methods. A wound dressing with an affixed appurtenance is single use and disposable after use. For example, a caregiver can require a new wound dressing every 24 hours (1 day) for an acute wound. Any wound dressing utilized in this type of situation would, consequently, be of a size and shape to remain affixed to the wound region over the course of at least a 24 hour period and then removed for disposal. An appurtenance to a wound dressing intended for use over the course of a 24 hour time period, similarly should be of a size, shape, material fabrication, and capabilities to function while affixed to the wound dressing over the 24 hour period that the dressing is in use. As an additional example, a caregiver can decide that for another type of wound, such as a chronic wound, the wound dressing needs to be removed and replaced once every 3 days, or every 4 days, or every 5 days, or every 6 days, or every 7 days.

Correspondingly, an appurtenance affixed to a wound dressing intended for use over the course of at least 3 to 7 days should be of a size, shape, material fabrication, and capabilities to function while affixed to the wound dressing over at least the 3 to 7 day period that the dressing is in use. In embodiments wherein an appurtenance is intended for reuse, such as reuse on a second or subsequent wound dressing used over a wound, the appurtenance should be of a size, shape, material fabrication and capabilities to function during the entire intended use, including the time period of removal from a first wound dressing and application to a second wound dressing.

Figures 2A and 2B depict further aspects of some embodiments of appurtenances to wound dressings. Figures 2 A and 2B depict cross-section views of an appurtenance 120 to a wound dressing 115. As illustrated in Figure 2 A, the appurtenance 120 includes a substantially planar section and a projection 200. The substantially planar section includes a surface 230 configured to substantially conform with an outer surface of the wound dressing 115. In some embodiments, the surface 230 of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include adhesive of a type expected to irreversibly adhere to the surface of the wound dressing 115. In some embodiments, the surface 230 of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include adhesive of a type expected to adhere to the surface of the wound dressing 115 for a period of time, and to be removable. In some embodiments, the surface 230 of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include barbs, hooks, pins, prongs or other extensions configured to adhere or fix onto the outer surface of the wound dressing 115 (see, e.g. Figs. 11A and 1 IB). For example, an appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include barbs, hooks, pins, prongs or other extensions that irreversibly adhere to the outer surface of the wound dressing 115, such as by imbedding into the outer surface. For example, an appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include barbs, hooks, pins, prongs or other extensions that reversibly adhere to the outer surface of the wound dressing 115, such as by reversibly interacting with extensions projecting from the outer surface.

The appurtenance 120 depicted in Figures 2 A and 2B includes a projection 200. As shown in Figures 2A and 2B, the projection extends from a surface 230 of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115. The single projection depicted in Figures 2 A and 2B projects at an angle from the plane formed by the substantially planar section of the appurtenance 120 conforming to the surface of the wound dressing 115. This angle is depicted in Figure 2 A as Θ. In Figures 2A and 2B, for example, the angle shown as Θ is approximately 135 degrees. However, as will be more evident from further description below (see, e.g. in relation to Figs 10A, 10B, 11 A and 1 IB), in some embodiments an appurtenance 120 can include a plurality of projections 200. Depending on the embodiment, the projections 200 can also be at a variety of angles relative to the section of the appurtenance 120 conforming to the surface of the wound dressing 115. For example, in some embodiments, one or more projections can be at angles less than approximately 135 degrees, between approximately 135 degrees and approximately 90 degrees, or substantially at approximately 90 degree angles relative to a planar section of the appurtenance 120. In some embodiments, an appurtenance 120 includes a substantially planar region including a transmission unit, wherein the substantially planar region is configured to conform with an outer surface of the wound dressing 1 15, and one or more projections 200 projecting substantially perpendicular to the surface 230 configured to conform with an outer surface of the wound dressing 1 15.

Depending on the embodiment, the projections 200 can project in a direction substantially away from the surface of the appurtenance configured to conform with an outer surface of the wound dressing 1 15 (e.g. as in Figs. 2A and 2B), or angle in a direction substantially perpendicular to the surface 230 configured to conform with an outer surface of the wound dressing 1 15 of the appurtenance (e.g. as shown in Figs. 9A and 9B). Some embodiments include at least one projection 200 which is curvilinear. Some embodiments include at least one projection 200 which is a composite shape. In embodiments including one or more projections that are not substantially straight, an angle (e.g. Θ as illustrated in Figure 2A) of the projection 200 can be determined by the angle formed at the base of the projection immediately adjacent to the surface of the appurtenance configured to conform with an outer surface of the wound dressing 1 15.

The projection 200 can be a substantially hollow tubular structure. Although not illustrated in Figures 2A and 2B in this view, a substantially hollow tubular structure of the projection 200 includes an opening on the distal end of the projection 200. While the projection 200 depicted in Figures 2A and 2B can be a substantially tubular structure, in some embodiments projections can be of different shapes and conformations. For example, a projection 200 can be solid, tubular, conical, cylindrical, tapered, curved, angular or other shape or combination of shapes as appropriate to the specific

embodiment. Embodiments including a plurality of projections can include projections of different sizes and shapes. A projection 120 can be substantially straight and form a substantially linear internal channel (e.g. as depicted in Figs 2A, 2B, 8A and 8B), or it can be curved and form a substantially curvilinear internal channel (e.g. as depicted in Figs 9A and 9B). The drawings illustrated herein are not to scale. The drawings illustrated herein represent relationships and shapes of the items described. Although not expressly illustrated herein, a projection 200 can be relatively large relative to the total size of the appurtenance. For example, the volume of a projection or a group of projections attached to an appurtenance can be 51%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% of the volume of the portion of the appurtenance configured to conform with an outer surface of a wound dressing (e.g. the substantially planar region as illustrated in Figs. 2A and 2B). Similarly, a projection 200 can be relatively small relative to the total size of the appurtenance. For example, the volume of a projection or a group of projections attached to an appurtenance can be 49%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, or 5% of the volume of the portion of the appurtenance configured to conform with an outer surface of a wound dressing (e.g. the substantially planar region as illustrated in Figs. 2A and 2B). In some embodiments, a projection 200 is located at an edge region of the substantially planar region of the appurtenance 120, and in some embodiments a projection 200 is located substantially centrally to the planar surface 230 of the appurtenance 120 configured to conform with an outer surface of the wound dressing 1 15. In some embodiments, a substantially planar appurtenance 120 includes at least one projection 200 wherein the entire appurtenance 120 is of a size and shape to be secured against an external surface of a wound dressing 1 15 with force, for example from a human thumb or finger.

In some embodiments, an appurtenance 120 can be fabricated with one or more regions configured for the attachment of different modules. In some embodiments, an appurtenance 120 includes modules that are configured for removal and replacement. During fabrication, a basic appurtenance structure can be utilized and different specific modules added as desired in a particular embodiment. For example, an appurtenance 120 can be fabricated with at least one region configured to attach a projection. For example a region configured to attach a projection can include a region with a surface conforming to an outer surface of the projection. For example a region configured to attach a projection can include a conduit configured to align with the hollow interior of the projection. The region of the appurtenance 120 configured to attach a projection can be configured for attachment of different projection types, depending on the embodiment. For example, the region of the appurtenance 120 configured to attach a projection can be configured for attachment of projections of different lengths or different materials as desired in the construction of a particular embodiment. In some embodiments, an appurtenance 120 can have multiple regions configured for attachment of multiple projections of different types. In some embodiments, an appurtenance 120 can have one or more removable antenna modules. For example, an appurtenance 120 can have one or more removable power source modules, such as batteries or solar cells. In some embodiments, a module can include a spacer element, or a component configured to assist in physically positioning one or more other modules. An appurtenance 120 can be fabricated from a variety of materials, as appropriate to an embodiment. An appurtenance 120 can be fabricated, for example, substantially from a plastic material. For example, a structural portion, such as a shell or base can be fabricated from a plastic material. For example, one or more projections can be fabricated from a plastic material. An appurtenance 120 can be fabricated, for example, from one or more acrylics, polyesters, silicones, polyurethanes and halogenated plastics. An appurtenance 120 can include one or more projections 200 fabricated, for example, from one or more plastic materials. An appurtenance 120 can include one or more projections 200 fabricated, for example, from one or more acrylics, polyesters, silicones,

polyurethanes and halogenated plastics. An appurtenance 120 can be fabricated from one or more bio-compatible materials, for example bio-compatible plastics, resins, epoxies and metals. An appurtenance 120 can be fabricated from one or more composite materials, such as plastic with an overlay of epoxy or plastic with an overlay of one or more metals. An appurtenance 120 including a transmission unit can include, for example, one or more metal components, for example as circuitry or as one or more antennas. An appurtenance 120 including a transmission unit can include, for example, stainless steel, copper or zinc alloy. An appurtenance 120 can be fabricated from one or more ceramic materials, such as within a transmission unit. Generally, it is envisioned that materials with low weight will be suitable for a variety of appurtenance embodiments, so as to reduce weight and associated physical stress on a wound dressing. Similarly, it is envisioned that materials with sufficient strength and toughness to be fabricated into small and thin components will be desirable for fabrication of appurtenance embodiments. As the appurtenances are to be permanently affixed to the wound dressings and disposed of with the wound dressings, materials that do not require special handling or disposal are preferable in most embodiments.

In some embodiments, the appurtenance 120 includes a substrate, (e.g. 250) that is configured to attach to the wound dressing 115. For example, the substrate can be configured as a support for other features of the appurtenance 120. In some embodiments, the substrate includes a substantially planar structure wherein the area of surface 230 is less than the area of the wound dressing 115 (see, e.g. Figs. 12-17). In some

embodiments, the substrate is configured to irreversibly attach directly to an external surface of the wound dressing 115. In some embodiments, the substrate includes an adhesive on a surface conforming to an external surface of the wound dressing 115 (e.g. surface 230 in Fig. 2A). For example, the surface conforming to an external surface of the wound dressing 115 can include a glue, epoxy, sealant, mucilage, paste or other binder material. In some embodiments, the surface of the substrate conforming to an external surface of the wound dressing 115 can include an adhesive covered by a removable protective sheet configured for detachment and exposure of the adhesive when the appurtenance 120 is attached to the wound dressing 115. In some embodiments, the surface 230 of the substrate of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include barbs, hooks, pins, prongs or other extensions configured to adhere or fix into the outer surface of the wound dressing 115 (see, e.g. Figs. 11A and 1 IB). In some embodiments, the surface 230 of the substrate of the appurtenance 120 configured to conform with an outer surface of the wound dressing 115 can include a mixture or combination of any of the above.

In some embodiments, the substrate includes a flexible material. For example, the substrate can include a pliable plastic, a woven fabric material, soft mesh or other flexible material. In some embodiments, the substrate includes a rigid material. For example, the substrate can include at least one rigid plastic material in a location configured to provide support for a portion of the appurtenance. For example, the substrate can include at least one rigid plastic material at a location configured to attach a projection, the rigid plastic configured to provide physical support for the attached projection. In some embodiments, the substrate includes at least one bio-compatible material. For example, the substrate can include one or more bio-compatible plastic materials, one or more bio-compatible fabric materials, or one or more bio-compatible metals.

Figure 2 A depicts a cross section view of an appurtenance 120 adjacent to a wound dressing 115. As shown in Figure 2A, the wound dressing 115 includes a dressing layer 220 and an outer layer 210. Not all wound dressings 115 should be expected to include multiple layers, and it is to be expected that some wound dressings 115 substantially include only a wound dressing material and not additional layers, structures or coverings. However, as illustrated in Figures 2A and 2B, in some embodiments wound dressings 115 include a plurality of layers. For example, a wound dressing 115 can include one or more outer layers 210 configured to protect and isolate the wound dressing layer(s) from microbes, external dirt and debris, dryness, wetness or other external factors. An outer layer can be fabricated from materials such as firm plastics or mesh materials. An outer layer can include a surface larger than the surface of the wound dressing layer, and can include adhesives on that surface configured to adhere the entire wound dressing to a body surface. A wound dressing 115 can include one or more layers of wound dressing 220 materials, such as gauze, films, foams, or sponges. A wound dressing 115 can include one or more layers of hydrogels, colloid gels, and medicinal agents impregnated within one or more layers of the wound dressing 220 or on a surface of the wound dressing 220 configured to face a wound.

A surface 230 of an appurtenance 120 can be configured to conform to the surface of the outer layer 210 of a wound dressing 115. For example, the surface can be of a size and shape that substantially conforms with the surface of the wound dressing 115. A surface 230 of an appurtenance 120 can include barbs, hooks, pins, prongs or other extensions configured to reversibly or irreversibly stick into the outer surface of the wound dressing 115 (see, e.g. Figs. 11A and 1 IB). A surface 230 of an appurtenance 120 can include one or more adhesives of a type to attach the appurtenance 120 to the wound dressing 115.

Figure 2B illustrates the appurtenance 120 and the wound dressing 115 of Figure

2 A after the appurtenance 120 is affixed to the wound dressing 125. As illustrated in Figure 2B, a projection 200 of an appurtenance 120 can be configured to pierce through the outer layer 210 and into a wound dressing layer 220. A projection 200 of an appurtenance 120 can be of a size and shape to project from the outer surface of the wound dressing 115 to within layers of the wound dressing 115. A projection 200 can be of a size and shape to extend into an interior region of the wound dressing 115. A projection 200 can be of a size and shape to project within an interior region of the wound dressing 115. As shown in Figure 2B, a projection 200 can be of a size and shape to project underneath one or more superficial structures of the wound dressing 115 (such as an outer layer 210) when the wound dressing 115 is in use. A projection 100 can be of a size and shape to project through a width of the wound dressing 1 15 when the appurtenance 120 is attached to the wound dressing 125 (see, e.g. Fig. 8B). Also as illustrated in Figure 2B, a projection 200 extending within the layers of the wound dressing 125 can be positioned so that fluids, (depicted as dotted arrows,) can enter a hollow within the projection 200 through capillary action.

Figure 2B also illustrates that in some embodiments a cover 240 is attached to the surface of the appurtenance 120 as well as to the surface of the wound dressing, such as to an outer layer of the wound dressing 210. An appurtenance 120 can include a substantially planar cover, the cover including an adhesive on a surface conforming to a surface of a wound dressing, the substantially planar cover configured to cover a location where the projection extends into the wound dressing. A cover 240 can be fabricated, for example, from a flexible plastic or mesh material. A cover 240 can be fabricated, for example, from an inflexible plastic or mesh material and configured in a size and shape to conform with the surfaces of the appurtenance 120 as well as to the surface of the wound dressing 1 15. A cover 240 can include adhesive on a surface facing the appurtenance and the wound dressing, the adhesive configured to attach the cover to the appurtenance and to the wound dressing. A cover 240 can be configured to stabilize the position of the appurtenance 120 relative to the wound dressing 1 15 when the appurtenance is affixed to the wound dressing 125 (e.g. as in Fig. 2B). A cover 240 can be configured to secure the appurtenance 120 relative to the wound dressing 1 15 when the appurtenance is affixed to the wound dressing 125 (e.g. as in Fig. 2B). A cover 240 can be configured to seal the juncture between the appurtenance 120 and the wound dressing 1 15, for example from dirt, debris, wetness or microbes that can enter the interior of the wound dressing if the juncture is not sealed. A cover 240 can be configured to seal an potential gaps between the projection 200 of the appurtenance 120 and the wound dressing 1 15, for example to seal any potential gaps from dirt, debris, external wetness or microbes that can enter the interior of the wound dressing if the gap is not sealed.

In some embodiments, an appurtenance 120 to a wound dressing 1 15 is

substantially sterilized prior to use. For example, the appurtenance 120 can be treated with one or more chemical disinfectants or UV surface radiation for a period of time sufficient to substantially sterilize the appurtenance 120 prior to use. For example, the appurtenance 120 can be treated with one or more antimicrobial gasses, for example ethylene oxide (ETO), prior to use. For example, the appurtenance 120 can be treated with a chemical sterilizing agent, such as hydrogen peroxide in liquid or vapor form, prior to use. For example, the appurtenance 120 can be treated with steam as an anti-infective prior to use. In some embodiments, an appurtenance 120 to a wound dressing 1 15 includes a sterile wrapper. For example, an appurtenance 120 to a wound dressing 1 15 can be stored and/or transported within a sterile wrapper, such as a firm paper wrapper or a plastic film. A sterile wrapper configured for storage and/or transport of an appurtenance can be treated to minimize contamination, for example coated with one or more antimicrobial agents. Figure 3 illustrates additional aspects of some embodiments of appurtenances to wound dressings. In some situations, a medical caregiver can choose a wound dressing that is not a single unit, but a group of distinct units that together in situ on a body part form a complete, composite wound dressing. For example, a caregiver can choose a composite wound dressing made up from a group of butterfly dressings {e.g. SteriStrip™). As illustrated in Figure 3, a composite wound dressing can include a plurality of wound dressings 115 as well as at least one wound dressing 125 with an affixed appurtenance 120. When the composite wound dressing is placed in position on a body part 110, such as a leg, the wound dressing 125 with an affixed appurtenance 120 can be included with the grouping of wound dressings 115.

Figure 4 illustrates additional aspects of some embodiments of appurtenances to wound dressings similar to that depicted in Figure 3. In some situations, a caregiver can choose a wound dressing that is not a single unit, but a group of distinct units that together in situ on a body part form a complete, composite wound dressing. For example, a caregiver can choose a composite wound dressing made up from a group of butterfly dressings {e.g. SteriStrip™ adhesive strips). In some embodiments, a caregiver can choose a compression bandaging system as part of a wound dressing. For example, a caregiver can choose a multi-layer compression bandaging system such as the Profore™ System or the Proguide™ System, both manufactured by Smith & Nephew. In some embodiments, a caregiver can choose a negative pressure wound therapy system, such as the Renasys™ system or the Pico™ system, both manufactured by Smith & Nephew, , or the V.A.C.™ system manufactured by Kinetic Concepts, Inc. (KCI). As illustrated in Figure 4, an appurtenance 120 can be positioned on a body part 110, such as a leg, in a region adjacent to a wound 100. A series of wound dressings 115 can be positioned around and over at least a portion of the appurtenance 120 and affixed to the appurtenance 120 to form a composite wound dressing with an affixed appurtenance unit 125. For example, the appurtenance 120 can be interleaved with the individual units of wound dressings 115 and affixed to one or more of the wound dressings 115 to form a composite wound dressing with an affixed appurtenance unit 125. An appurtenance 120 extending within the layers of the wound dressing 125 can be positioned so that fluids can enter an opening in the appurtenance 120 through capillary action.

Figure 5 A and 5B illustrate aspects of some embodiments of an appurtenance 120 to a wound dressing 115 in a cross-sectional view. In some embodiments, an appurtenance 120 includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing 115. Figure 5 A depicts an appurtenance 120 of a size and shape to substantially penetrate an outer cover 210 and into a dressing region 220 of a wound dressing 115. The appurtenance 120 depicted in Figures 5 A and 5B is a cross section view of a substantially conical shape with an opening at the lower region of the cone (downward in Figures 5A and 5B). The main structure of the appurtenance is depicted as 250. As illustrated in Figure 5A and Figure 5B, some embodiments include a cover 240. A cover 240 can be of a size and shape to seal the surface of the appurtenance 120 exposed at the surface of the wound dressing. Figure 5B depicts the appurtenance 120 affixed to the wound dressing 125. The appurtenance 120 depicted in Figure 5B projects through the outer layer 210 of the wound dressing and into the interior wound dressing layer 220. Also as illustrated in Figure 5B, an appurtenance 120 extending within the layers of the wound dressing 125 can be positioned so that fluids, depicted as dotted arrows, can enter an opening in the appurtenance 120 through capillary action.

Figure 6 illustrates aspects of an embodiment of an appurtenance 120, such as that depicted in Figures 5A and 5B. The appurtenance 120 depicted in a cross-sectional view in Figure 6 includes one or more sensors 660, a processor 640 operably attached to the one or more sensors 660, at least one transmitter unit 620 operably attached to the processor 640, and an enclosure 600 of a height and width to fit substantially within an interior region of a wound dressing (see, e.g. Figure 5B). The enclosure 600 depicted in Figure 6 is a cross sectional view of a substantially cone shaped enclosure 600. As shown in Figures 5A, 5B and 6, in some embodiments the enclosure is a substantially cylindrical structure, wherein the largest width of the substantially cylindrical structure is less than the smallest width of the wound dressing. In some embodiments, the enclosure 600 includes a substantially conical or a substantially conical frustum shaped structure. In some embodiments, the enclosure 600 includes a cross-sectional view square area that is substantially equal to or less than one tenth of a square area of a largest surface of the wound dressing. As shown in Figure 6, the enclosure 600 includes one or more flanges 610 at the upper edge of the substantially conical structure of the enclosure 600. The flanges 610 are positioned to locate the enclosure 600 relative to an outer surface of a wound dressing, and can be positioned to provide a surface for attachment of a cover (see, e.g. Fig. 5B). A flange 610 can include a flange region configured to cover part of an outer surface of the wound dressing when the appurtenance 120 is positioned for use with the wound dressing. One or more flanges 610 can be located on the enclosure 600 in a manner to functionally inhibit the movement of the enclosure 600 into the interior of the wound dressing layer. The one or more flanges 610 can be located on the enclosure 600 in a manner to expand a portion of the circumference of the enclosure 600 and prevent the appurtenance 120 from moving into the wound dressing beyond that expanded

circumference. The enclosure 600 also includes one or more barbs 680 positioned to hold the appurtenance 120 in place relative to the affixed wound dressing and to prevent the appurtenance 120 from slipping relative to the wound dressing. Some embodiments include an enclosure 600 with one or more walls, the walls forming a flange 610 on an edge of the enclosure 600, the flange 610 positioned to attach a fastener between a surface of the wound dressing and the enclosure 600. Some embodiments include one or more walls, the walls forming one or more flanges 610 on the edge of the enclosure 600, the one or more flanges 610 including one or more projections from a surface of the one or more flanges 610, the one or more projections positioned to pierce an outer surface of the wound dressing. For example, one or more flanges 610 can include one or more barbs, points or projections positioned to pierce an outer surface of a wound dressing and assist in maintaining the position of the appurtenance relative to the wound dressing.

Some embodiments include a fastener configured to form a seal between an edge of an enclosure 610 and a surface of a wound dressing. For example, an edge of an enclosure 610 can include an adhesive configured to seal the edge of the enclosure 610 to a surface of the wound dressing. For example, as illustrated in Figure 7, the fastener can include a substantially planar cover 240 with an upper surface and a lower surface, the lower surface conforming to both the edge of the enclosure 610 and to the surface of the wound dressing, and adhesive on at least a portion of the substantially planar cover 240.

Some embodiments include a piercing region operably attached to an edge of the enclosure 600 distal to an edge of the enclosure 600 adjacent to an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. For example, the enclosure 600 can include a tip, point, edge or surface projection configured to pierce a wound dressing surface when the appurtenance is affixed to the wound dressing.

As shown in Figure 6, in some embodiments the one or more sensors 660 are positioned substantially within the enclosure 600. As illustrated in a cross-sectional view in Figure 6, in some embodiments the enclosure 600 is configured to substantially enclose the one or more sensors 660. In some embodiments, the enclosure 600 includes one or more walls forming the enclosure 600, and one or more openings 670 within the one or more walls, the one or more openings 670 forming a conduit between a region exterior to the enclosure 600 and a region interior to the enclosure 600. For example, one or more openings 670 can form a conduit for analytes to pass from the interior of the wound dressing into the interior of the enclosure and for the analytes to come in contact with one or more sensors 660. The enclosure 600 can include an opening 670 at the end configured to be positioned within the wound dressing, and the one or more sensors 660 can be positioned adjacent to the opening 670. The one or more sensors 660 can be positioned adjacent to or within the opening 670 in a manner to allow the one or more sensors 660 to detect analytes within the wound dressing, such as through fluid flow (depicted as dotted arrows) from the interior of the wound dressing to a region adjacent to a sensor 660.

Although a single opening 670 within the enclosure 600 is depicted in Figure 6, in some embodiments there can be a plurality of openings in the enclosure, for example arrayed as a series of holes or a mesh- like structure. Some embodiments include a plurality of openings 670, wherein each opening 670 includes an associated sensor 660, such associated sensors 660 can be the same or different type of sensor 660.

As depicted in Figure 6, in some embodiments the processor 640 operably connected to the one or more sensors 660 is positioned substantially within the enclosure 600. Figure 6 depicts a single sensor 660 positioned substantially within the enclosure 600. In some embodiments, there can be a plurality of sensors 660, which can be of the same or different types. The one or more sensors 660 can include at least one sensor responsive to changes in capacitance. A connector 650, such as a wire connector, can operably connect the one or more sensors 660 to the processor 640. As illustrated in Figure 6, in some embodiments the at least one transmitter unit 620 operably attached to the processor 640 is positioned substantially within the enclosure 600. A connector 630, such as a wire connector, can operably attach the processor 640 to the transmitter unit 620. Some embodiments include a processor 640 and a transmitter unit 620 that are powered through received signals (i.e. passive RFID). Some embodiments include a power source, such as a battery 690. A power source such as battery 690 can be integrated with the transmission unit 620, as depicted in Figure 6. A power source such as battery 690 can be integrated with the processor 640. In some embodiments, a power source such as a battery 690 can be connected to the transmitter unit 620 and/or the processor 640, such as with a wire connector.

A variety of sensors can be utilized in different embodiments of the appurtenances, depending on factors such as the intended use of the appurtenance, size, weight, cost, bio- compatibility, safety and ease of disposal. "Sensors," as used herein, can be of a variety of types depending on the embodiment. One or more sensors can include at least one sensor responsive to changes in capacitance, or a measure of the ability of a configuration of materials to store electric charge. A general review of biosensors that detect changes in the dielectric properties of an electrode surface can be found in Berggren et al.,

"Capacitive Biosensors," Electroanalysis vol. 13, no. 3, 173-180, (2001), which is incorporated herein by reference. For example, one or more sensors can include a micromechanical biosensor with a fixed- fixed beam attached to an interdigitated capacitor {see, for example, Lim et al., "A Micromechanical Biosensor with Interdigitated Capacitor Readout," Proceedings of the 2011 IEEE/ICME International Conference on Complex Medical Engineering, May 22-25, Harbin, China, which is incorporated herein by reference). Sensors can also include nanowire nanosensors, for example as described in Cui et al., "Nanowire Nanosensors for Highly Sensitive and Selective Detection of Biological and Chemical Species," Science, vol. 293, 1289-1292 (2001), which is incorporated herein by reference. Sensors can include those utilizing antibodies secured to a graphene substrate. See Tehrani et al., "Detection of Monoclonal Antibodies using

Chemically Modified Graphite Substances," IEEE Sensors 2010 Conference Proceedings, 428-431, (2010), which is incorporated herein by reference. In some embodiments, sensors include aptamer-modified graphene field-effect transistors, see Ohno et al, "Graphene Field-Effect Transistors for Label-Free Biological Sensors," IEEE Sensors 2010 Conference Proceedings, 903-906, (2010), which is incorporated herein by reference. A sensor in an appurtenance can interact with a sensor present in a wound dressing, for example as described in US Patent No. 6,283,938 to McConnell, titled "Medicating Bandage and Controllable Permeable Membrane," which is incorporated herein by reference. A sensor can include a field effect transistor (FET), such as described in US Patent No. 7,507,675 to Zuilhof et al, titled "Device Manufacturing Method and Device," which is incorporated herein by reference. A sensor can include a nano- cantilever device, such as described in US Patent No. 7,612,424 to Espinosa and Ke, titled "Nano electromechanical Bistable Cantilever Device," which is incorporated herein by reference.

Sensors such as those described herein can be configured to sense fluids. Sensors such as those described herein can be configured to sense one or more components of a fluid. Sensors such as those described herein can be configured to sense one or more analytes within a fluid. As used herein, fluid includes both gasses and liquids individually or as mixtures. Sensors described herein can detect fluids, whether in gaseous state or liquid state. If the fluid is a liquid, it can be drawn into an appurtenance through capillary action. If the fluid is a gas, it can be drawn into the appurtenance through gravity (i.e. where the appurtenance is oriented on the top of a wound dressing over a wound). In some embodiments, the appurtenance includes a micropump positioned to move fluids through a projection and into the appurtenance in a position adjacent to a sensor. Each sensor is in fluid communication with the portion of the appurtenance relative to the insertion point into the wound dressing, or the projection 200. In some embodiments, the appurtenance includes a sealed chamber that is under vacuum and connected to the projection. When the seal is broken, it sucks up the fluid into the tube in response to the low (or negative) air pressure in the tube.

As illustrated in Figure 6, in some embodiments a processor 640 is operably attached to the one or more sensors 660. For example, the processor can be connected with a wire connector 650, configured to allow the sensor to send information to the processor. The processor 640 is configured to receive information from the sensor. The processor 640 can include one or more processing cores, and can include any of a number of types of processors commonly in use. The processor 640 can include volatile or nonvolatile memory. The appurtenance 120 can include a volatile or non- volatile memory unit operably attached to the processor 640. The processor 640 can hold in memory a unique identifier for the specific appurtenance 120. For example, the processor 640 can include an identifying number specific to that appurtenance 120.

The appurtenance 120 can include an energy storage unit. For example, an appurtenance 120 can include an energy storage unit, such as a battery, operably attached to the processor 640. In some embodiments, the appurtenance 120 does not store energy. The appurtenance 120 can include an energy harvesting unit, such as a unit configured to obtain energy from electromagnetic waves. See, for example, US Patent No. 7,479,886 to Burr titled "Antenna Capacitance for Energy Storage" and Sample et al., "Photovoltaic Enhanced UHF RFID Tag Antennas for Dual Purpose Energy Harvesting," 2011 IEEE International Conference on RFID, 146- 153 (2011), which are each incorporated herein by reference. In some embodiments, the appurtenance 120 includes an indicator operably attached to the processor 640, the indicator positioned on a side of the appurtenance adjacent to an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. For example, the indicator can include a least one of: a visual indicator, a vibratory indicator, or an auditory indicator. See, for example, US Patent Application No. 2009/0167495 to Smith, titled "Radio Frequency Identification Tags Adapted for Localization and State Indication," which is incorporated herein by reference.

As shown in Figure 6, in some embodiments at least one transmitter unit 620 is operably attached to the processor 640. In some embodiments, the at least one transmitter unit 620 and the processor 640 are operably connected with a wire connection 630.

A "transmitter unit," as used herein, can be one or more of a variety of units that are configured to send and/or receive signals, such as signals carried as electromagnetic waves. In embodiments where the appurtenance includes a substrate, the transmission unit can be attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal. A transmitter unit generally includes at least one antenna and associated circuitry. A transmitter unit can include a transmitter and a receiver. A transmitter unit can include volatile or non-volatile memory. A transmitter unit can include a processor. A transmitter unit can be operably connected to an energy source, such as a battery. In some embodiments of an

appurtenance, it is desirable to include a self-compensating antenna, such as described in US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates having Differing Dielectric Constant Values," which is incorporated herein by reference. A transmitter unit can be operably connected to a processor, as illustrated in Figure 6. A transmitter unit can be operably connected to a sensor. A transmitter unit can be configured to transmit a signal in response to an interrogation signal. A transmitter unit can include an energy harvesting unit, such as a unit configured to obtain energy from electromagnetic waves. A transmitter unit can include a transponder utilizing

electromagnetic waves, for example as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference. A transmitter unit can include an oscillator and encoder configured to generate a programmable pulse position-modulated signal in the radio frequency range. See, for example, US Patent No. 4,384,288 to Walton, titled "Portable Radio Frequency Emitting Identifier," which is incorporated herein by reference. A transmitter unit can include a radio frequency identification device (RFID). A transmitter unit can be configured to be a transmitter of signals in the UHF range. A transmitter unit including an RFID device can be configured to transmit signals in the UHF standard range utilized in a global region, as illustrated in the "Worldwide RFID UHF Map" by

Intelleflex Corporation (©2009), which is incorporated herein by reference. A transmitter unit can include a radio frequency identification device (RFID), which can be a passive RFID device, a semi-passive RFID device, or an active RFID device, depending on the embodiment. See, for example, Chawla and Ha, "An Overview of Passive RFID," IEEE Applications and Practice, 11-17 (September 2007), which is incorporated herein by reference. A transmitter unit can include a battery-assisted passive RFID device, such as sold by Alien Technology®, Morgan Hill, CA, such as described in the brochure from Alien Technology® titled "Battery Assisted Passive Tags" and incorporated herein by reference. A transmitter unit can include an optical transmitter unit. A transmitter unit can be configured to transmit at approximately 13.56 megahertz (MHz), or within the ISO 14443 standard parameters. See Patauner et al., "High Speed RFID/NFC at the Frequency of 13.56 MHz," presented at the First International EURASIP Workshop on RFID

Technology, pages 1-4, 24-25 September 2007, Vienna Austria, which is incorporated herein by reference. A transmitter unit can include at least two antennas. A transmitter unit can include a self-compensating antenna system. An antenna can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference. A transmitter unit can include a hybrid backscatter system configured to function in an RFID, IEEE 802.1 lx standard and Bluetooth system. See, for example, US Patent No. 7,215,976 to Brideglall, titled "RFID Device, System and Method of Operation Including a Hybrid backscatter-based RFID Protocol Compatible with RFID, Bluetooth and/or IEEE 802.1 lx Infrastructure," which is incorporated herein by reference. A transmitter unit can be configured to transmit at approximately 131 kilohertz (KHz), for example as part of a RuBee™ (IEEE standard 1902.1) system (sold, for example, by Visible Assets™, Inc.). See for example: the description of RuBee™ systems from the Visible Assets™ webpage; Stevens et al, "RuBee (IEEE 1902.1) - The Physics Behind, Real-Time, High Security Wireless Asset Visibility Networks in Harsh Environments," a white paper from Visible Assets™; and in US Patent Application No. 2007/0171076 to Stevens and Waterhouse, titled "Low-frequency Radio Tag Encapsulating System," each of which are incorporated herein by reference. A transmitter unit can include a near field communication (NFC) device. A transmitter unit can include a Wireless Identification and Sensing Platform (WISP) device, manufactured by Intel Corporation, such as described in the "WISP: Wireless Identification and Sensing Platform" webpage (downloaded on October 28, 2011) incorporated herein by reference. A transmitter unit can be operably coupled to a sensor, such as a sensor that detects changes in capacitance (see, e.g. Sample et al, "A Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which is incorporated herein by reference). A transmitter unit can be operably coupled to a sensor, such as described in: Ruhanen et al, "Sensor-enabled RFID Tag and Handbook," from Building Radio Frequency Identification for the Global Environment (2008); Sample et al, "Design of an RFID-Based Battery-Free

Programmable Sensing Platform," IEEE Transactions on Instrumentation and

Measurement, vol. 57, no. 11, 2608-2615 (2008); Yeager et al, "Wirelessly-Charged UHF Tags for Sensor Data Collection," 2008 IEEE International Conference on RFID, April 16-17, 2008, pages 320- 327; US Patent Nos. 5,904,671 and 6,348,640 to Navot and Botton, each titled "Tampon Wetness Detection System;" US Patent No. 7,446,660 to Posamentier titled "Passive Environmental RFID Transceiver;" and US Patent No.

5,704,352 to Tremblay and Buckles, titled "Implantable Passive Bio-Sensor," which are each incorporated herein by reference. A transmission unit can be operably coupled to a data storage unit, for example as described in US Patent No. 7,825,776 to Smith and Haehnel, titled "Device Configuration with RFID," and US Patent Application No.

2009/0243813 to Smith at al, titled "Wireless Programming of Non-Volatile Memory with Near-Field UHF Coupling," which are each incorporated herein by reference.

In some embodiments, the transmitter unit can include an acoustic transmitter. For example, a transmitter unit can include a piezoelectric speaker. A variety of suitable piezoelectric speakers are available, including from Murata Manufacturing Co., Ltd., with North American corporate headquarters in Smyrna, GA (see, e.g. the Murata catalog titled "Piezoelectric Sounds Components" labeled P37E and dated January 28, 2010, which is incorporated herein by reference). Some embodiments can include acoustic transmitter units such as those manufactured by Advanced Telemetry Systems (headquartered in Isanti, MN) for the Pacific Northwest National Laboratory (see, e.g. JSATS Acoustic Transmitter information sheet from the Pacific Northwest National Laboratory, updated March 2010, which is incorporated herein by reference). In some embodiments, an appurtenance can include a piezoelectric speaker configured as part of an acoustic transmitter and also to act as a signaling device (e.g. to generate a beeping noise in response to a signal from the processor).

In some embodiments, the transmitter unit can include an ultrasonic transmitter. In some embodiments, the transmitter unit can include an ultrasonic transducer. Multiple examples of ultrasonic transmitters and transducers are commercially available, often marketed under the term "ultrasonic sensors" as it is used in the industry (see, e.g. the Murata catalog titled "Ultrasonic Sensor" labeled S15E and dated October 31, 2008, which is incorporated herein by reference). The transmitter unit can be configured as part of an ultrasonic ranging system. See: Wang, "A Design Method of Ultrasonic Ranging System with High Accuracy," Journal of Computational Information Systems, 7: 7 pages 2444-2451 (2011), which is incorporated herein by reference. The transmitter unit can be configured to communicate with an ultrasonic communication system. See: Chen and Wu, "Ultrasonic System with Infrared Communication Technology," Journal of Computers, vol. 6, no. 11, pages 2468-2475 (2011), which is incorporated herein by reference.

In some embodiments, the transmitter unit can include an optical transmitter. For example, an optical transmitter unit can include one or more white light emitting diodes (LEDs). For example, an optical transmitter unit can include an infrared laser. In some embodiments, optical transmitter units can be desirable to minimize interference from nearby electrical equipment, such as medical equipment. See: Kavehrad, "Sustainable Energy-Efficient Wireless Applications Using Light," IEEE Communications Magazine, vol. 48, no. 12, pages 66-73, (2010); and Fadlullah and Kavehrad, "Indoor High- Bandwidth Optical Wireless Links for Sensor Networks" Journal of Lightwave

Technology, vol. 28, no. 21, pages 3086-3094 (2010), which are incorporated herein by reference.

Figure 7 illustrates some aspects of an embodiment of an appurtenance 120. The appurtenance has been irreversibly affixed to a wound dressing to form a combination unit 125. Although the appurtenance 120 of Figure 7 is an embodiment distinct from the embodiment illustrated in Figure 6, the embodiment illustrated in Figure 6 is configured similarly in that the enclosure 600 fits substantially within the main thickness of the wound dressing interior region 220. Figure 7 depicts an appurtenance 120 including an enclosure 600 and a sensor unit 660 substantially surrounded by the enclosure 600. In some embodiments, the enclosure 600 is fabricated from one or more flexible materials, for example a flexible plastic material. Figure 7 illustrates an appurtenance to a wound dressing affixed to a wound dressing 125. Figure 7 shows that the appurtenance includes: a sensing unit 660 including one or more sensors, the sensors positioned substantially within an enclosure of a height and width to fit substantially within an interior region of a wound dressing; a transmission unit 620 including a processor and at least one transmitter unit operably attached to the processor; and a connector 700 between the sensing unit 660 and the transmission unit 620, the connector 700 configured to convey signals between the one or more sensors and the transmission unit 620. For example, the connector 700 can include a wire. The sensor unit 660 is positioned adjacent to an opening 670 in the enclosure 600, the opening 670 positioned on the enclosure 600 at a position to allow analytes to flow (as depicted by hatched arrows) from an interior region of the wound dressing 220 into a position in contact with the sensor unit 660. In some embodiments, the sensor unit 660 can be configured to be responsive to changes in circuitry capacitance. As shown in Figure 7, the sensor unit 660 is operably attached to a transmission unit 620 via one or more connectors 700 including wires. The transmission unit 620 can include, for example, one or more antennas, a non-volatile memory, and related circuitry. The transmission unit 620 can include, for example, an antenna and a receiver operably attached to the antenna. The transmission unit 620 can include, for example, non-volatile memory. The transmission unit 620 can include, for example, a substrate including at least one surface configured to conform to an exterior surface of a body. For example, the transmission unit 620 can, in whole or part, be attached to an exterior surface of the body adjacent to the wound dressing. The transmission unit 620 can, in whole or part, be attached to an exterior surface of the body in situations, for example, where the main wound dressing is too small to accommodate the square area of the transmission unit 620, or where other space parameters make that option desirable. In an embodiment of an appurtenance 120, such as illustrated in Figure 7, wherein the transmission unit 620 including at least one antenna is positioned on top of the wound dressing, it can be desirable to include a self-compensating antenna system, such as described in US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates having Differing Dielectric Constant Values," which is incorporated herein by reference. A cover 240 is positioned at the upper surface of the appurtenance 120, the cover 240 positioned to secure the appurtenance 120 relative to the surface of the wound dressing 220. The cover 240 can be configured to seal the junction between the edge of the enclosure 600 and the edge of the wound dressing. In some embodiments, the appurtenance can include an indicator operably attached to the transmission unit 620. For example the appurtenance can include an indicator which is at least one of: a visual indicator, a haptic indicator, or an auditory indicator.

Figures 8 A and 8B illustrate additional aspects of an appurtenance 120 to a wound dressing 115. As illustrated in Figure 8 A, an appurtenance 120 can include a projection 200. The appurtenance 120 can include a surface 230 conforming to an outer surface of a wound dressing 115. The wound dressing 115 can include an outer layer 210 and a wound dressing layer 220. As shown in Figure 8B, when the appurtenance 120 is irreversibly affixed to the wound dressing to form an appurtenance- wound dressing combination unit 125, the projection 200 includes a region 800 that projects through the layers of the wound dressing 210, 220 and beyond the surface of the wound dressing that is configured to face the wound. As shown in Figures 8A and 8B, in some embodiments a projection 200 is of a size and shape to project through a width of the wound dressing when the appurtenance 120 is attached to the wound dressing. In embodiments where the wound dressing is intended to overlay an additional bandage or dressing, the additional projection region 800 can be configured to project into the additional bandage or dressing. For example, in some situations, a medical caregiver can select a treatment for a wound that includes a layer of gauze, potentially impregnated with a medicinal agent, at the surface of the wound and then a wound dressing overlay over the gauze layer. A region 800 of a projection 200 from an appurtenance 120 can project into such a gauze layer.

Also as illustrated in Figure 8B, in some embodiments the appurtenance wound dressing unit 125 includes at least one cover 240. The at least one cover 240 can include at least one substantially planar cover 240, the cover 240 including an adhesive on a surface conforming to a surface of the wound dressing, the substantially planar cover 240 configured to cover at least a part of the projection 200. For example, the cover 240 can seal the junction region between the appurtenance 120 and the wound dressing 115, for example from external dirt, debris, wetness and microbes. Figures 9 A and 9B illustrate aspects of an appurtenance 120 configured for irreversible attachment to a wound dressing 115. A shown in Figure 9A, an appurtenance 120 can include a projection 200. The projection 200 can be configured as a tapered conical shape. The projection 200 can be configured in a curved shape. A curved, hook- like shape for a projection 200, as illustrated in Figures 9A and 9B, can be desirable for ease of attachment to the wound dressing 115. A single motion, as depicted in the hatched arrow, can be sufficient for a user to position and affix an appurtenance 120 with a hooklike projection 200 to a wound dressing 115. The appurtenance 120 can include a surface 230 conforming to an outer surface of a wound dressing 115. The wound dressing 115 can include an outer layer 210 and a wound dressing layer 220. When the appurtenance 120 is affixed to the wound dressing 115 to form a wound dressing- appurtenance combination unit 125, as shown in Figure 9B, the curved projection 200 can be stable within the layers 210, 220 of the wound dressing. The appurtenance wound dressing unit 125 can also include at least one cover 240. The at least one cover can seal the junction between the appurtenance and the wound dressing, and can also stabilize the appurtenance relative to the wound dressing.

In some embodiments, an appurtenance 120 includes a plurality of projections 200. As shown in Figures 10A and 10B, an appurtenance 120 can include more than one projection 200. The projections 200 can be spaced at regular or irregular intervals over a surface of the appurtenance 120. The projections 200 can all be of substantially the same size and shape, as shown in Figures 10A and 10B, or they can be of different sizes and shapes to project at different levels and amounts into a wound dressing 115. The projections 200 of an appurtenance 120 can be selected relative to the intended use of the appurtenance 120, including an associated wound dressing 115, the intended length of time of use, and monitoring sensitivity of the appurtenance 120. Projections 200 at different levels and amounts into a wound dressing 115 can be oriented, for example, to form conduits for fluid flow between different layers of a wound dressing and sensor(s) of the appurtenance 120. Projections 200 of different levels and amounts into a wound dressing 115 can be useful, for example, to fully monitor a wound dressing 115 with multiple layers. Figure 10A illustrates that a wound dressing 115 can include an outer layer 210 and an inner layer 220. As shown in Figure 10B, in embodiments wherein an appurtenance 120 includes a plurality of projections 200 of a similar size and shape, the projections would be expected to end at a similar relative depth or width of the wound dressing 115 when the appurtenance is affixed to the wound dressing as a unit 125. In an embodiment wherein an appurtenance includes a plurality of projections of different sizes and shapes (not illustrated in Figure 10B), the projections would reach to different levels or depths of a wound dressing. Projections 200 of different levels and amounts into a wound dressing 115 can be useful, for example, to fully monitor a wound dressing 115 with multiple functional regions or layers, such as regions or layers with different absorbance properties. Projections 200 of different levels and amounts into a wound dressing 115 can be useful, for example, to efficiently monitor a wound dressing 115 of sufficient thickness that fluid flow throughout the entire wound dressing 115 requires an excess amount of time. Also as shown in Figure 10B, in some embodiments an appurtenance wound dressing unit 125 can also include at least one cover 240.

The projections 200 can be functionally the same, or they can be different.

Projections 200 at different levels and amounts into a wound dressing 115 can be oriented, for example, to form conduits for fluid flow between different regions of a wound dressing 115 and/or a wound bed region and sensor(s) of the appurtenance 120. Projections 200 can include the same type of sensors, or be connected to the same type of sensors, or they can include different types of sensors, or be connected to different types of sensors. For example, in some embodiments sensors detecting pH changes in a wound dressing can be more desirable in a central location of the appurtenance 120 and sensors detecting wetness can be more desirable at an edge region of the appurtenance 120. In this example, pH changes can indicate potential infection in the central wound region, while edge wetness can indicate that the wound dressing is saturated and should be replaced. Sensors for pH suitable for some embodiments are known. See, for example, the "flexible, iridium oxide pH sensor for wound dressing material" project from the University of Texas at Arlington, the information sheet for which, with UTA reference number 08-21, is herein incorporated by reference.

Figures 11 A and 1 IB show additional features that can be present in an

appurtenance 120 to a wound dressing 115. As shown in Figure 11A, in some

embodiments an appurtenance 120 to a wound dressing 115 can include a plurality of projections 200. One or more of the projections 200 can include a barb-like feature 680, wherein the barb-like feature 680 is configured to bend during insertion of the projection 200 into one or more layers 210, 220 of a wound dressing 115 but then prevent the movement of the projection 200 away from the wound dressing 115. For example, as illustrated in Figures 11 A and 1 IB, in some embodiments one or more projections 200 include at least one extension that protrudes outwards from the side of the projection 200 at an angle larger than 90 degrees from the direction of motion of the projection 200 into the wound dressing 115. The at least one extension from the projection 200, therefore, acts as a barb to prevent the appurtenance 120 moving away from the wound dressing 115 (as illustrated in Figure 1 IB). An appurtenance 120 can also include one or more barbed attachments 1100 configured to irreversibly attach the appurtenance 120 to the wound dressing 115. As shown in Figure 1 IB, the one or more barbed attachments 1100 can be configured to traverse multiple layers 210, 220 of the wound dressing 115 and, therefore, stabilize the attachment of the appurtenance 120 to the wound dressing 115 in the wound dressing- appurtenance combination unit 125.

Figure 12 illustrates aspects of an appurtenance affixed to a wound dressing unit 125. The view illustrated in Figure 12 is a substantially top-down view, as seen from the top of an appurtenance affixed to a wound dressing unit 125 looking down on to the unit. The side of the wound dressing- appurtenance combination unit 125 illustrated in Figure 12 is the side that would be away from a wound during use. The side of the wound dressing- appurtenance combination unit 125 illustrated in Figure 12 is the opposing face to the surface of the unit configured for use adjacent to a body part. As shown in Figure 12, a wound dressing can include a wound covering region 1200 and an edge region 1210. The wound covering region 1200 can include one or more layers of a wound dressing, such as gauze, foam, hydrocolloids, and other types of wound dressings singly or in combination. The edge region 1210 can include, for example, a structural region configured to provide shape and support to the wound covering region 1200. The edge region 1210 can include, for example, an adhesive configured to attach the edge region 1210 to a surface of a body part in an area adjacent to a wound. The edge region 1210 can include, for example, a cover configured to seal the edge region 1210 and the adjacent body part surface from substances moving between the edge region 1210 and the adjacent body part surface. For example, the edge region 1210 can include a cover configured to prevent wetness, debris, dirt or microbial agents from travelling between the edge region 1210 and the body surface.

As shown in Figure 12, an appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a substrate 1290. The substrate 1290 can include, for example, a flexible plastic, which can be configured in a thin film or as a mesh of no more than a few millimeters (mm) in thickness. For example, the substrate 1290 can be no more than 3 mm, or no more than 5 mm, thick depending on the embodiment. The substrate 1290 can include, for example, a flexible paper material. The substrate 1290 can include, for example, a composite material. The substrate 1290 can include, for example, one or more materials with properties such as durability, strength, cost, weight, bio-compatibility and disposability that are suitable for a given embodiment. The substrate 1290 is configured to irreversibly attach to the wound covering region 1200 of the wound dressing. For example, the substrate 1290 can include an adhesive material on the face configured to conform to the surface of the wound dressing 1200. For example, the substrate 1290 can include one or more barbs, hooks or other projections (see, e.g. Figures 11 A and 1 IB) on the face configured to conform to the surface of the wound dressing 1200.

Also as illustrated in Figure 12, the appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a transmission unit 1280 attached to a surface of the substrate. The transmission unit 1280 includes circuitry 1270 and at least one antenna 1220. Although the transmission unit 1280 is illustrated as visible in Figure 12, in some embodiments all or part of the transmission unit 1280 will be covered and not be visible. The transmission unit 1280 is configured to transmit a signal. As illustrated in Figure 12, an antenna 1220 can be a substantially planar antenna, such as commonly used in radio frequency identification (RFID) or near field communication

(NFC) units. Prior to use, the antenna 1220 can be detuned with a removable surface layer of a conductive material. This can be desirable to reduce excess RFID signals, for example from appurtenances 120 in storage prior to attachment to a wound dressing. See US Patent No. 7,724,136 to Posamentier, titled "Revealable RFID Devices," which is incorporated herein by reference. The circuitry 1270 of the transmission unit 1280 can include a variety of components, as desired in a particular embodiment. The circuitry 1270 of the transmission unit 1280 can include a processor 1230. The circuitry 1270 can include non- volatile memory 1240. The circuitry 1270 can include a transmitter 1250. The circuitry 1270 can include one or more additional modules 1260. For example, the circuitry 1270 can include an energy source, such as a battery. For example, the circuitry 1270 can include a receiver. For example, the circuitry 1270 can include a transceiver. For example, the circuitry 1270 can include an additional antenna. For example, the circuitry 1270 can include volatile memory. The circuitry 1270 can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference.

In some embodiments, the transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate and a surface of the wound dressing. In some embodiments, the transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on a surface of the appurtenance. In some

embodiments, the transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate and a surface of the wound dressing. See, for example, US Patent Nos. 6,693,513 and 6,037,879 to Tuttle, titled "Wireless Identification Device, RFID Device with Push-On/Push-Off Switch, and Method of Manufacturing Wireless Identification Device," and US Patent No. 6,863,220 to Selker, titled "Manually Operated Switch for Enabling and Disabling an RFID Card," as well as Sample et al., "A Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which are each incorporated herein by reference.

Figure 12 illustrates that the appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a projection 200.

Although the projection 200 is displayed for the purposes of illustration, when an appurtenance 120 is affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 in normal use, the projection 200 would extend into an interior region of the wound dressing {see, e.g. Figs. 2B, 8B, 9B, 10B and 1 IB), and, therefore, not be visible from a superficial view. As illustrated in Figure 12, in some embodiments a projection 200 includes a physical conduit configured to permit fluid to flow from the interior region of the wound dressing 1200 to a location in contact with the transmission unit 1280. For example, in some embodiments a projection 200 includes a physical conduit configured to allow a flow of the fluid from the interior region of the wound dressing 1200 to a location in contact with the antenna 1220 of the transmission unit 1280. The projection 200 can include a substantially hollow tubular structure. The projection 200 includes an opening 670 at the end of the projection 200 distal to the end of the projection 200 adjacent to the substrate 1290. The projection 200 can be of a size and shape to project from the outer surface of the wound dressing to within layers of the wound dressing. The projection 200 can be of a size and shape to project underneath one or more superficial structures of the wound dressing when the wound dressing is in use. The projection 200 can be of a size and shape to project through a width of the wound dressing when the appurtenance is attached to the wound dressing. See, e.g. Figs. 2B, 8B, 9B, 10B and 11B.

In some embodiments, the projection 200 is fabricated from a plastic material. For example, the projection 200 can be fabricated from a pliable plastic material. For example, the projection 200 can be fabricated from a bio-compatible plastic material. For example, the projection 200 can be fabricated from a plastic material that can be sterilized prior to use of the appurtenance 120.

Figure 13 illustrates further aspects of an appurtenance 120 such as that shown in Figure 12. Figure 13 illustrates that the appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a projection 200. Although the projection 200 is shown in Figure 13 for the purposes of illustration, in actual use the projection 200 would project into one or more layers of the wound covering region 1200 of the wound dressing. Figure 13 also illustrates that the wound covering region 1200 contains a fluid 1300. The fluid 1300 can include, for example, blood, serum, pus, wound exudates, excess saline, or other fluids that can be present in the interior of the wound dressing. For example, the fluid 1300 can include blood, such as when an acute wound is bleeding excessively, as can occur when a suture has broken open. For example, the fluid may include gas, such as emitted from infected tissue (e.g. N0₂). For example, the fluid 1300 can include wound exudates, such as those that are characteristic of infected wounds (see for example, Cutting and Harding, "Criteria for Identifying Wound

Infection," Journal of Wound Care, vol. 3, no. 4, 198-201 (1994), which is incorporated herein by reference).

Figure 13 also illustrates that the fluid 1300 has moved into the projection 200 through the opening 670. The fluid can flow through the projection 200 through a variety of forces depending on the embodiment, for example through capillary action, under a physical pressure differential, or diffusion. When the migrated fluid 1310 comes into contact with the transmission unit 1280, the migrated fluid 1310 modulates the

transmission unit 1280. For example, when the migrated fluid 1310 comes into contact with the antenna 1220 of the transmission unit 1280, the fluid 1310 can modulate the antenna 1220 through alterations of the frequency to which the antenna 1220 responds. The migrated fluid 1310 can result in the loss of antenna 1220 function. For example, when the migrated fluid 1310 comes into contact with the transmission unit 1280, the fluid 1310 modulates activity of the circuitry unit 1270. The migrated fluid 1310 can result in the loss of circuitry unit 1270 function. The migrated fluid 1310 can result in the loss of circuitry unit 1270 function, for example through alterations of the electrical paths of the circuitry within the circuitry unit 1270. The migrated fluid 1310 can result in the mitigation of ability of the transmission unit 1280 to transmit a signal. The migrated fluid 1310 can result in the loss of ability of the transmission unit 1280 to transmit a signal. This loss can be detected by an associated signal reader and/or system (see, e.g. Figs. 18, 19, 20 and 21).

In some embodiments, the appurtenance 120 includes a second antenna (not illustrated in Fig. 13, but see Figs. 16 and 17). In a situation where the activity of a first antenna is mitigated by contact with fluid (e.g. as fluid 1310 illustrated in Figure 13), the second antenna can still retain its original activity and function. For example, an appurtenance with a first antenna and a second antenna can transmit a characteristic signal, such as an identifying signal, from each antenna in the absence of fluid within the appurtenance. In a situation where the first antenna transmits a modulated signal, or no longer transmits signals, due to contact of the antenna to fluid that has flowed from the interior of the wound dressing through the projection to come into contact with the first antenna, the second antenna will still be operational. Therefore, an associated signal reader and/or system (see, e.g. Figs. 18, 19, 20 and 21) can detect a loss of signal from the first antenna and a maintained signal from the second antenna of an appurtenance. A signal reader and/or system can be programmed to initiate a warning signal to a user when such conditions are detected.

As illustrated in Figures 12 and 13, in some embodiments an appurtenance 120 to a wound dressing 1200, 1210 includes: a substrate 1290; a transmission unit 1280 that is a passive RFID unit attached to the substrate 1290; and a substantially hollow projection 200 operably attached to the substrate 1290, the projection 200 including a first end and a second end, the first end of a size and shape to extend within a wound dressing, the second end extending into the passive RFID unit.

Figure 14 illustrates an appurtenance 120 affixed to a wound dressing 1200, 1210 to form a wound dressing- appurtenance combination unit 125. The appurtenance 120 includes a substrate 1290 and a transmission unit 1280 attached to a surface of the substrate 1290. The transmission unit 1280 includes an antenna 1220 and circuitry 1270. The circuitry 1270 of the transmission unit 1280 can include a processor 1230. The circuitry 1270 can include volatile or non- volatile memory 1240. The circuitry 1270 can include a transmitter 1250. The circuitry 1270 can include one or more additional modules 1260. For example, the circuitry 1270 can include an energy source, such as a battery. For example, the circuitry 1270 can include a receiver. For example, the circuitry 1270 can include a transceiver. For example, the circuitry 1270 can include an additional antenna.

The appurtenance 120 includes a projection 200. Although the projection 200 is displayed for the purposes of illustration, when an appurtenance 120 is affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 in normal use, the projection 200 would extend into an interior region of the wound dressing (see, e.g. Figs. 2B, 8B, 9B, 10B and 1 IB), and, therefore, not be visible from a superficial view. The projection 200 includes one or more sensors 1410 and at least one substantially hollow enclosure substantially encircling the one or more sensors 1410, the at least one substantially hollow enclosure including one or more openings 670 within the enclosure distal to the attachment to the substrate. As shown in Figure 14, a sensor 1410 is within the substantially hollow enclosure of the projection 200, in a region adjacent to the opening 670 in the projection 200. The one or more sensors 1410 can be entirely or partially internal to the projection. A sensor 1410 can be configured to be responsive to a change in capacitance, and be operably connected to the transmission unit 1280. Figure 14 also illustrates that there is a connector 1400 between the transmission unit 1280 and the one or more sensors 1410. The connector 1400 can be a wire.

As illustrated in Figure 15, some embodiments include a device, including: a wound dressing 1200, 1210; a transmission unit 1280 irreversibly attached to the wound dressing 1200, 1210, the transmission unit 1280 including circuitry 1270 and at least one antenna 1220; a selectively actuatable switch 1500 operably connected to the transmission unit 1280; and a projection 200 operably attached to the switch 1500, the projection 200 extending within an interior region of the wound dressing 1200. Although the projection 200 is visible for purposes of illustration, in actual use a projection 200 attached to an appurtenance 120 affixed as to a wound dressing 1200, 1210 would project within the wound dressing 1200. As illustrated in Figure 15, the selectively actuatable switch 1500 is operably connected to the transmission unit 1280 with a wire connection 1530. As depicted in Figure 15, the projection 200 is operably attached to the switch 1500 through a wire connection 1510 between the switch 1500 and a sensor 1410 substantially within the projection 200. Figure 15 also illustrates that some embodiments include a wound dressing unit 125 includes: a wound dressing 1200, 1210; a substrate 1290 attached to an external surface of the wound dressing 1200, 1210; a transmission unit 1280 attached to a surface of the substrate 1290, the transmission unit 1280 including circuitry 1270 and at least one antenna 1220, the transmission unit 1280 configured to transmit a signal; a selectively actuatable switch 1500 operably connected to the transmission unit 1280; and a projection 200 operably attached to the switch 1500, the projection 200 extending through the external surface of the wound dressing 1200, 1210. Although Figure 15 is a top-down view, it is intended that the projection 200 is angled away from the surface plane of the wound dressing 1200, 1210 (e.g. as illustrated in Figs. 2A, 2B, 8A and 8B). As shown in Figure 15, the projection 200 can include a sensor 1410 operably connected to a selectively actuatable switch 1500 through a wire connection 1520. The sensor 1410 can be configured to actuate the switch in response to a stimulus. The sensor 1410 can be configured to cause a change in the state of the switch in response to a stimulus, such as the presence of an analyte.

A "selectively actuatable switch," as used herein, refers to a switch of sufficient structure to allow or disallow a transmission unit 1280 to transmit a signal in response to a sensor 1410. A selectively actuatable switch includes a switch that can be turned between settings (i.e. "on" and "off) in response to a stimulus. A selectively actuatable switch can, for example, be coupled to a transmission unit 1280 that includes an RFID device. See, for example, US Patent No. 7,411,505 titled "Switch Status and RFID Tag," which is incorporated herein by reference. A selectively actuatable switch can be a binary switch, or a switch with substantially two settings (i.e. "on" and "off). A selectively actuatable switch can be configured to be irreversible, or to irreversibly go from one state to a second state. A selectively actuatable switch can be configured to be responsive to a change in capacitance.

Figure 16 illustrates aspects of an appurtenance 120 to a wound dressing 1200,

1210. The appurtenance 120 is irreversibly attached to a wound covering 1200 portion of a wound dressing. The appurtenance 120 includes a substrate 1290 and a projection 200 attached to the substrate 1290. As shown in Figure 16, there is a transmission unit 1280 attached to the substrate 1290. The transmission unit 1280 includes a first antenna 1600, a second antenna 1610 and circuitry 1270 operably connected to both the first antenna 1600 and the second antenna 1610. The circuitry 1270 is operably connected to the first antenna 1600 with a wire connection 1680. The circuitry 1270 is operably connected to the second antenna 1610 with a wire connection 1690. The circuitry 1270 of the transmission unit 1280 can include a variety of components, as desired in a particular embodiment. The circuitry 1270 of the transmission unit 1280 can include a processor 1630. The circuitry 1270 can include non- volatile memory 1640. The circuitry 1270 can include a transmitter 1650. The circuitry 1270 can include one or more additional modules 1660. For example, the circuitry 1270 can include an energy source, such as a battery. For example, the circuitry 1270 can include a receiver. For example, the circuitry 1270 can include a transceiver. For example, the circuitry 1270 can include volatile memory. For example, the circuitry 1270 can include an additional antenna. The circuitry 1270 can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self- Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference.

The embodiment illustrated in Figure 16 includes a projection 200 attached on one end to the substrate 1290, and the other end including an opening 670. The projection includes a sensor 1410 within the substantially hollow projection 200. In an actual appurtenance- wound dressing combination unit 125, the projection 200 would extend into the wound dressing 1200, however for the purposes of illustration the projection 200 is made visible in Figure 16. The sensor 1410 is operably attached to a selectively actuatable switch 1500 with a wire 1520. The selectively actuatable switch 1500 is operably attached to the first antenna 1610 with a wire 1510.

Figure 17 shows aspects of an appurtenance 120 to a wound dressing 1200, 1210. The appurtenance 120 is irreversibly attached to a wound covering 1200 portion of a wound dressing. The appurtenance 120 includes a substrate 1290 and a projection 200 attached to the substrate 1290. As shown in Figure 17, there is a transmission unit 1280 attached to the substrate 1290. The transmission unit 1280 includes a first antenna 1700, a second antenna 1710 and circuitry 1270 operably connected to both the first antenna 1700 and the second antenna 1710. The circuitry 1270 is operably connected to the first antenna 1700 with a wire connection 1780. The circuitry 1270 is operably connected to the second antenna 1710 with a wire connection 1790. The circuitry 1270 of the transmission unit 1280 can include a variety of components, as desired in a particular embodiment. The circuitry 1270 of the transmission unit 1280 can include a processor 1730. The circuitry 1270 can include non- volatile memory 1740. The circuitry 1270 can include a transmitter 1750. The circuitry 1270 can include one or more additional modules 1760. For example, the circuitry 1270 can include an energy source, such as a battery. For example, the circuitry 1270 can include a receiver. For example, the circuitry 1270 can include a transceiver. For example, the circuitry 1270 can include an additional antenna. The circuitry 1270 can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to

Forester, titled "Self-Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference.

The embodiment shown in Figure 17 includes a projection 200 attached on one end to the substrate 1290, and the other end including an opening 670. The projection includes a sensor 1410 within the substantially hollow projection 200. In an actual appurtenance- wound dressing unit 125, the projection 200 would extend into the wound dressing 1200, however for the purposes of illustration the projection 200 is made visible in Figure 17. The sensor 1410 is operably attached to a selectively actuatable switch 1500 with a wire connection 1520. The selectively actuatable switch 1500 is operably attached to the circuitry with a wire connection 1510.

Figure 18 illustrates aspects of a system including a wound dressing with an affixed appurtenance combination unit 125. As shown in Figure 18, a wound dressing with an affixed appurtenance combination unit 125 is placed over a wound on a body part 110 of a patient. For example, the body part 110 can have been subject to a surgery, and therefore to have an acute wound. For example, the body part 110 can include an ulcer, and therefore have a chronic wound. The wound dressing with an affixed appurtenance combination unit 125 receives signals 1840 from a local unit 1810 and transmits signals 1840 to the local unit 1810. For example, the wound dressing with an affixed

appurtenance combination unit 125 can include a passive RFID configured to transmit signals 1840 after receiving signals 1840 from a proximal RFID reader device in the local unit 1810. The wound dressing with an affixed appurtenance combination unit 125 can be configured, in some embodiments, to transmit signals 1340 in response to an electrochemical reaction generating a current within a fluid-activated voltaic cell of the appurtenance.

A local unit 1810 can include a handheld device. For example, the local unit 1810 can include a distinct handheld device. For example, the local unit 1810 can be included as part of a larger handheld unit, for example a tablet, a laptop, a cell phone, a personal communication device, or similar types of devices. A local unit 1810 can be configured to be attached to a location, such as the end of a hospital bed, a medical stand, a bedside table, a wheelchair, or similar device. A local unit 1810 can be configured to be integrated into a piece of mobile equipment, such as the end of a hospital bed, a medical stand, a wheelchair, or similar device. For example, a local unit can be integrated with a medical cart, as described in US Patent No. 7,667,606 to Packert et al., titled "RF Enabled Surgical Cart and Use of Same in Operating Room Environment," which is incorporated herein by reference. A local unit 1810 can be configured to be integrated into a furnishing. For example, a local unit 1810 can be integrated into a hospital bed, a bedside hospital monitor, a bedside table, a medical chair, a medical table, or similar furnishing. A local unit 1810 can include a display unit 1820. In some embodiments, there can be a secondary device configured to relay signals from a wound dressing with an affixed appurtenance combination unit 125 to the local unit 1810, for example as described in US Patent No. 7,986,235 to Posamentier titled "RFID Receive- Only System," which is incorporated herein by reference. For example, a secondary device configured to relay signals from a wound dressing with an affixed appurtenance combination unit 125 to the local unit 1810 can be configured to increase the signal strength to a local unit 1810 positioned a distance away from the wound dressing with an affixed appurtenance combination unit 125. For example, a secondary device configured to relay signals from a wound dressing with an affixed appurtenance combination unit 125 to the local unit 1810 can be configured to relay signals from a plurality of wound dressings with affixed appurtenance units 125 to a single local unit 1810. A local unit 1810 can include an input device 1830, for example a keyboard. Although the local unit 1810 illustrated in Figure 18 includes a keyboard as an input device 1830, in some embodiments the input device 1830 can include other types of input devices, for example a touchscreen, stylus, keypad, or voice recognition system. A user 1800, such as a medical caregiver, operates the local unit 1810. A user 1800 can include a medical caregiver, such as a nurse or doctor, or a patient or other individual monitoring the wound dressing. Although user 1800 is

shown/described herein as a single illustrated figure, those skilled in the art will appreciate that user 1800 can be representative of a human user, a robotic user (e.g., computational entity), and/or substantially any combination thereof (e.g., a user can be assisted by one or more robotic agents) unless context dictates otherwise. Those skilled in the art will appreciate that, in general, the same can be said of "sender" and/or other entity-oriented terms as such terms are used herein unless context dictates otherwise. A user 1800 can utilize a local unit 1810 through a user interface, for example one or more buttons, a keyboard, a touchscreen, a voice recognition device, a stylus, or other means.

A local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenances 125 automatically. For example, local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenances 125 at least one of: every 10 minutes; every 20 minutes; every 30 minutes; every hour; every 2 hours; or every 3 hours. A local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenances 125 on a schedule selected by the user 1800. For example, local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenances 125 on at least one of: an hourly schedule; a schedule of every 30 minutes for 4 hours, followed by hourly signals; a schedule of every 10 minutes for 6 hours, followed by signals every 30 minutes; or a schedule provided by the user through the user interface (e.g. the keyboard 1830). A local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenance combination units 125 on a preset schedule which is selected by the user 1800. For example, local unit 1810 can be configured to send signals to one or more wound dressings with attached appurtenance combination units 125 on at least one of: a schedule preset to monitor a wound after surgery; a schedule preset to monitor a chronic wound; an hourly schedule; a schedule of every 2 hours; a schedule of hourly during the day and every 2 hours at night; or other preset schedules.

A local unit 1810 can be configured to monitor for signals to one or more wound dressings with attached appurtenances 125 automatically. The signals 1840 sent from the wound dressing with attached appurtenance unit 125 to the local unit 1810 can be radio frequency signals in a particular wavelength, or range of wavelengths. For example, the signals can be in the UHF range, such as a UHF sub-range commonly used in a particular geographic region. See, for example the "Worldwide RFID UHF Map" by Intelleflex Corporation (©2009), which is incorporated herein by reference. For example, the signals can be in a range specified by an industry standard. For example, the signals can be in the approximately 13.56 megahertz (MHz) range, or within the ISO 14443 standard parameters. For example, the signals can be in the IEEE 802.1 lx standard or the

Bluetooth standard range. See, for example, US Patent No. 7,215,976 to Brideglall, titled "RFID Device, System and Method of Operation Including a Hybrid backscatter-based RFID Protocol Compatible with RFID, Bluetooth and/or IEEE 802.1 lx Infrastructure," which is incorporated herein by reference. For example, the signals can be in the approximately 131 kilohertz (KHz) range, for example as part of a RuBee™ (IEEE standard 1902.1) system (i.e. equipment sold by Visible Assets™, Inc.). See for example: the description of RuBee™ systems from the Visible Assets™ webpage; Stevens et al, "RuBee (IEEE 1902.1) - The Physics Behind, Real-Time, High Security Wireless Asset Visibility Networks in Harsh Environments," a white paper from Visible Assets™; and in US Patent Application No. 2007/0171076 to Stevens and Waterhouse, titled "Low- frequency Radio Tag Encapsulating System," each of which are incorporated herein by reference.

Similarly, the signals 1840 sent from the wound dressing with attached

appurtenance unit 125 to the local unit 1810 can be one of the types described above in relation to signals 1840 sent from the local unit 1810. In some embodiments, the wound dressing with attached appurtenance unit 125 includes a backscatter or reflective transmission device, and so the signals 1840 sent from the wound dressing with attached appurtenance unit 125 to the local unit 1810 can be backscatter or reflective signals. For example, as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and

Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference.

In some embodiments, the wound dressing with attached appurtenance unit 125 includes a backscatter or reflective transmission device, and so the signals 1840 sent from the wound dressing with attached appurtenance unit 125 to the local unit 1310 can include backscatter or reflective signals. For example, as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference.

The signals 1840 transmitted from the local unit 1810 or transmitted from the wound dressing with attached appurtenance combination unit 125 can be sent in a fixed direction from the signal source. The wound dressing with attached appurtenance combination unit 125 and the local unit 1810 can each include markings or other visible aspects directing a user how as to orient the wound dressing with attached appurtenance combination unit 125 and the local unit 1810 relative to each other for signal

directionality.

In many embodiments, it is envisioned that the signal strength of a signal 1840 transmitted from either the local unit 1810 or transmitted from the wound dressing with attached appurtenance combination unit 125 will be such that the signal 1840 will not travel a significant distance. The local unit 1810 and the wound dressing with attached appurtenance combination unit 125 can, therefore, need to be placed in reasonably close proximity for signals 1840 to travel between the devices. For example, the signal 1840 transmitted from either the local unit 1810 or transmitted from the wound dressing with attached appurtenance combination unit 125 can be such that the receiver of such signals should be within the same room. For example, the signal 1840 transmitted from either the local unit 1810 or transmitted from the wound dressing with attached appurtenance combination unit 125 can be such that the receiver of such signals should be within 10 feet. For example, the signal 1840 transmitted from either the local unit 1810 or transmitted from the wound dressing with attached appurtenance combination unit 125 can be such that the receiver of such signals should be within 3 feet.

Figure 19 illustrates aspects of a system including a wound dressing with an affixed appurtenance combination unit 125. As illustrated in Figure 19, a wound dressing with an affixed appurtenance combination unit 125 is placed over a wound on a body part 110 of a patient. The wound dressing with an affixed appurtenance combination unit 125 sends and receives signals 1840 from a local unit 1810. The local unit 1810 can be utilized by a user 1800.

Figure 19 illustrates aspects of the local unit 1810. The local unit 1810 includes a housing, with connected user interface and input components {e.g. a display and keyboard). The local unit 1810 can include a processor 1800. The local unit 1810 can include memory 1910. The memory 1910 can include, for example, non- volatile memory. The memory 1910 can include, for example, volatile memory. The local unit 1810 can include at least one antenna 1920. The local unit 1810 can include circuitry 1930, operably connected to the other components of the local unit 1810. The local unit 1810 can include one or more transmitters 1940. The local unit 1810 can include one or more receivers 1950. The local unit 1810 can include one or more power sources 1960, such as a battery, a solar cell, or a plug-in socket. The local unit 1810 can include logic 1970. The local unit 1810 can include other components 1980, 1990 as appropriate to a specific embodiment. The local unit 1810 can include, for example, an application specific intelligent microsensor as described in US Patent No. 6,889, 165 to Lind et al, titled "Application Specific Intelligent Microsensors," which is incorporated herein by reference. The local unit 1810 can include, for example, a distinct identification signal. The local unit 1810 can include, for example, a visible indicator, such as a light. The local unit 1810 can include, for example, an identification code specific to that local unit 1810.

Figure 20 shows aspects of a system including a wound dressing with an affixed appurtenance combination unit 125. As shown in Figure 20, a wound dressing with an affixed appurtenance combination unit 125 is placed over a wound on a body part 1 10 of a patient. The wound dressing with an affixed appurtenance combination unit 125 sends and receives signals 1840 from a local unit 1810. The local unit 1810 can be utilized by a user 1800.

Also as shown in Figure 20, the local unit 1810 can send and receive signals 2010 from a central assembly 2005. The local unit 1810 can send and receive signals 2010 with a wireless connection, as shown in Figure 20, or can send and receive signals 2010 through a wire connection. A central assembly 2005 includes at least one user interface device (e.g. a keyboard, touchscreen, display, etc.) which can be utilized by a system user 2000. A system user 2000 can include a medical caregiver, such as a nurse or doctor, or a patient caregiver, or other individual monitoring the wound dressing. Although system user 2000 is shown/described herein as a single illustrated figure, those skilled in the art will appreciate that system user 2000 can be representative of a human user, a robotic user (e.g., computational entity), and/or substantially any combination thereof (e.g., a user can be assisted by one or more robotic agents) unless context dictates otherwise. Those skilled in the art will appreciate that, in general, the same can be said of "sender" and/or other entity-oriented terms as such terms are used herein unless context dictates otherwise. Figure 20 illustrates aspects of some embodiments of a central assembly 2005. A central assembly can be located primarily or mainly in one or a limited number of machines, for example one or more computer servers. A central assembly 2005 can interface with, or include, a 2G-RFID-Based E-Healthcare system. See, for example, Chen et al, "A 2G-RFID-Based E-Healthcare System," IEEE Wireless Communications, February 2010, pages 37-43, which is incorporated herein by reference. A central assembly 2005 can interface with, or include, a digital management system, for example as discussed in: Fisher, "Indoor Positioning and Digital Management: Emerging

Surveillance Regimes in Hospitals" in T. Monahan (Ed), Surveillance and Security: Technological Politics and Power in Everyday Life (pp. 77-88), New York: Routledge (2006); and Fisher and Monahan, "Tracking the Social Dimensions of RFID Systems in Hospitals," International Journal of Medical Informatics 77 (2008) 176-183, which are each incorporated herein by reference. A central assembly 2005 can interface with, or include, a drug tracking system, as described, for example, in "RFID Systems for Pharmaceutical Distributors to Meet the New FDA Regulations on Drugs," white paper from Abhisam Software, 2006, which is incorporated herein by reference. The central assembly 2005 can include, for example, at least one transmitter 2020. The central assembly 2005 can include, for example, at least one receiver 2025. The central assembly 2005 can include, for example, at least one antenna 2030. The central assembly 2005 can include, for example, memory, which can include non- volatile memory or volatile memory. The central assembly 2005 can include, for example, circuitry 2040. The circuitry 2040 can be operably connected to other components of the central assembly 2005. The central assembly 2005 can include, for example, a power source 2045. A power source 2045 can include, for example, at least one battery, a plug-in connection, a wireless power source, or a solar cell. The central assembly 2005 can include, for example, a processor 2050. The central assembly 2005 can include, for example, logic 2055. The central assembly 2005 can include, for example, additional components 2060, 2065.

Figure 21 illustrates aspects of a system including a wound dressing with an affixed appurtenance combination unit 125. As illustrated in Figure 21, a wound dressing with an affixed appurtenance combination unit 125 is placed over a wound on a body part 110 of a patient. The wound dressing with an affixed appurtenance combination unit 125 sends and receives signals 1840 from a local unit 1810. The local unit 1810 sends and receives signals 2180 from a central assembly 2005. The central assembly 2005 illustrated in Figure 21 is in a "cloud" format, with a significant portion of its components distributed on a computer network, or a network of computing devices. The central assembly 2005 is configured to communicate with one or more interface devices 2105, for example an individual computer.

Depending on the embodiment, a cloud-based central assembly 2005 can include a plurality of components as illustrated in Figure 21. For example, a central assembly 2005 can include logic 21 10. For example, a central assembly 2005 can include circuitry 2120. The circuitry 2120 can be operably connected to other components of the central assembly 2005. For example, a central assembly 2005 can include memory 2130. For example, a central assembly 2005 can include one or more power sources 2140. For example, a central assembly 2005 can include at least one processor 2150. For example, a central assembly 2005 can include other components 2160.

Also as illustrated in Figure 21 , a central assembly 2005 can communicate with a remote device 2190 through signals 2070. Signals 2070 can be sent and received by an aspect of the central assembly 2005. Signals 2070 can be sent and received by the remote device 2190. Although the signals 2070 illustrated in Figure 21 are wireless signals, in some embodiments the central assembly 2005 and a remote device 2190 can communicate through a wired connection. The remote device 2190 can be, for example, a pager, cell phone, laptop, PDA, tablet, smart phone or other device. The remote device 2195 can be operated by a remote system user 2095. Some embodiments include a plurality of remote devices 2190, which can be operated by a plurality of remote system users 2195.

Some embodiments include a device for attaching an appurtenance to a wound dressing. Although in some embodiments, the appurtenance can be configured to be attached to a wound dressing without an additional device (e.g. with the pressure of a human finger or hand alone), in some embodiments a specific device for attaching an appurtenance to a wound dressing can be useful to ensure that the appurtenance is securely affixed to the wound dressing and/or to ensure positioning of the appurtenance relative to the wound dressing. A specific device for attaching an appurtenance to a wound dressing can be useful to minimize contamination of a clean or substantially sterile appurtenance. The device for attaching an appurtenance to a wound dressing can include: a base plate; a handle attached to the base plate; a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing; a handle attached to the holder region; and a pivot between the handle attached to the base plate and the handle attached to the holder region. For example, the device for attaching an appurtenance to a wound dressing can include a substantially planar base plate configured to position under the wound dressing during attachment. For example, a device for attaching an appurtenance to a wound dressing can be a pincer-like device, with two relative rotating arms that bring the appurtenance within the holder region down on the wound dressing on the base plate during attachment of the appurtenance to a wound dressing.

In some embodiments, the base plate of the device for attaching an appurtenance to a wound dressing includes: a substantially planar surface of a size and shape substantially corresponding to a substantially planar surface of the appurtenance; and a concavity within the substantially planar surface of the base plate, the concavity substantially corresponding to the height and cross-section of the appurtenance. This type of base plate can be particularly useful, for example, in embodiments wherein the appurtenance is of a size and shape that is of a size and shape difficult to grip with a normally-sized human hand. For example, an appurtenance can be too small for easy handling with a normally-sized adult human hand.

In some embodiments, the handle attached to the base plate of the device for attaching an appurtenance to a wound dressing includes: a handle of a size and shape configured for use by an adult human hand. In some embodiments, the handle attached to the base plate of the device for attaching an appurtenance to a wound dressing includes: a substantially linear handle attached at a less than 45 degree angle relative to the base plate. For example, the handle can be substantially linear but the attachment to the base plate at an end of the handle can be positioned at an angle less than a 45 degree angle relative to the substantial planes of the handle and the base plate.

In some embodiments, the holder region includes: a flange of a size and shape to retain a region of an appurtenance to a wound dressing adjacent to a surface of a wound dressing during attachment. For example, the flange region can be configured to improve stability of the appurtenance during attachment. In some embodiments, the holder region includes: a clamp of a size and shape corresponding to region of an appurtenance to a wound dressing. For example, the clamp can be positioned to orient the appurtenance during attachment.

In some embodiments, the handle attached to the holder region includes: a handle of a size and shape configured for use by an adult human hand. In some embodiments, the handle attached to the holder region includes: a substantially linear handle attached at a less than 45 degree angle relative to the holder region.

In some embodiments, the handle attached to the base plate and the handle attached to the holder region are of a substantially similar size and shape. For example, both of the handles can be of a size and shape configured for use by an adult human hand.

In some embodiments, the pivot between the handle attached to the base plate and the handle attached to the holder region includes: a rod traversing a cross-section of each of the handle attached to the base plate and the handle attached to the holder region when the respective handles are positioned adjacent to each other. For example, the rod can be positioned to orient and attach the handles relative to each other.

Some embodiments include a method of attaching an appurtenance to a wound dressing. Methods of attaching an appurtenance to a wound dressing can include the steps of: placing an appurtenance for a wound dressing in contact with an outer surface of the wound dressing; and providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing. In some embodiments, the placing an appurtenance for a wound dressing in contact with an outer surface of the wound dressing includes: removing an external cover of the wound dressing; and placing the appurtenance in contact with a superficial surface of the wound dressing.

In some embodiments, the providing pressure on the appurtenance includes providing manual pressure. In some embodiments, the providing pressure on the appurtenance includes providing pressure in a direction substantially perpendicular to the outer surface of the wound dressing. In some embodiments, the providing pressure on the appurtenance includes providing pressure in a direction substantially at an angle to the outer surface of the wound dressing.

Methods of attaching an appurtenance to a wound dressing can include the step of removing an external cover of the wound dressing from the outer surface of the wound dressing prior to placing the appurtenance in contact with the outer surface of the wound dressing. Methods of attaching an appurtenance to a wound dressing can include the step of sealing a region including an edge of the appurtenance and the area of the wound dressing adjacent to the edge of the appurtenance with a cover. Methods of attaching an appurtenance to a wound dressing can include the step of sealing a region including an edge of the appurtenance and the area of the wound dressing adjacent to the edge of the appurtenance by forcing one or more projections on the edge of the appurtenance into the outer surface of the wound dressing.

Figure 22 depicts aspects of a wound dressing 115 and some potential positions of an appurtenance 120A, 120B relative to the wound dressing 115. As shown in Figure 4, a wound dressing 115 can include an outer layer 210, a dressing layer 220 and a wound contact layer 2200. For example, the outer layer 210 can include a plastic film or mesh configured to protect the external surface of the wound dressing 115. The outer layer 210 can include at least one exterior surface 2210 positioned away from the wound 100 when the wound dressing 115 is in use. For example, the dressing layer 220 can include one or more layers of gauze or absorbent material. For example, the dressing layer 220 can include a hydrogel. For example, the dressing layer 220 can include one or more layers of foam dressing. For example, the wound contact layer 2200 can include a plastic mesh film configured to reduce chafing or adherence of the wound dressing 115 to the wound 100. For example, the wound contact layer 2200 can include a surface 2220 configured to substantially conform with an outer surface of the wound 100. For example, the wound contact layer 2200 can include a surface 2220 configured as a non-planar surface to substantially conform with an outer surface of the wound 100. For example, the wound contact layer 2200 can include a surface 2220 including a flexible material expected to substantially conform with an outer surface of the wound 100, such as a soft foam or gel material. As shown in Figure 22, some embodiments of the appurtenances 120A, 120B described herein are configured to be positioned within the layers of a wound dressing 115. As shown in Figure 22, an appurtenance 120 A can be positioned between an outer layer 210 and a dressing layer 220 of a wound dressing 115. Also as shown in Figure 22, an appurtenance 120 A can be positioned between a dressing layer 220 and a wound contact layer 2200 of a wound dressing 115. During use, the wound dressing 115 is condensed so that all of the layers 210, 220, 2200 are positioned adjacent to each other and also to any appurtenance 120 A, 120 B placed between the layers 210, 220, 2200. The wound dressing 115 with attached appurtenance 120 A, 120 B is then reversibly affixed to the surface of a body part 110 and covering a wound 100.

Figure 23 illustrates aspects of an appurtenance 120 affixed to a wound dressing unit 125. The view illustrated in Figure 23 is a substantially top-down view, as seen from the top of an appurtenance affixed to a wound dressing unit 125 looking down on to the unit. The side of the wound dressing- appurtenance combination unit 125 illustrated in Figure 23 is the side that would be away from a wound during use (e.g. surface 410 as shown in Figure 22). The side of the wound dressing- appurtenance combination unit 125 illustrated in Figure 23 is the distal face to the surface of the unit configured for use adjacent to a body part. As shown in Figure 23, a wound dressing can include a wound covering region 2300 and an edge region 2310. The wound covering region 2300 can include one or more layers of a wound dressing, such as gauze, foam, hydrocolloids, and other types of wound dressings singly or in combination. The edge region 2310 can include, for example, a structural region configured to provide shape and support to the wound covering region 2300. The edge region 2310 can include, for example, an adhesive configured to attach the edge region 2310 to a surface of a body part in an area adjacent to a wound. The edge region 2310 can include, for example, a cover configured to seal the edge region 2310 and the adjacent body part surface from substances moving between the edge region 2310 and the adjacent body part surface. For example, the edge region 2310 can include a cover configured to prevent wetness, debris, dirt or microbial agents from travelling between the edge region 2310 and the body surface.

Figure 23 illustrates an appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125. The appurtenance 120 includes a substrate 2385 configured to attach to the wound dressing 2300, 2310. The appurtenance 120 includes a fluid-activated voltaic cell 2360 attached to the substrate 2385. The appurtenance 120 includes a transmission unit 2380 attached to a surface of the substrate 2385, the transmission unit 2380 including circuitry 2330 and an antenna 2320. The transmission unit 2380 is configured to transmit a signal in response to current generated by the fluid-activated voltaic cell 2360. The fluid-activated voltaic cell 2360 is electrically connected to the transmission unit 2380 with a wire connector 2395. The appurtenance 120 includes a projection 200 operably attached to the fluid-activated voltaic cell 2360. The projection 200 is of a size and shape to extend into an interior region of the wound dressing 2300, 2310 (not depicted in Figure 23 for purposes of illustration of the structure of the appurtenance 120, but see Figure 2B). The projection 200 is configured to sample a fluid within an interior region of the wound dressing 2300, 2310. For example, the projection 200 includes an opening 2390 at the end of the projection 200 distal to the end of the projection 200 adjacent to the substrate 2385, the opening 2390 configured to allow fluid flow from an interior region of the wound dressing 2300, 2310 into the interior region 2375 of the fluid-activated voltaic cell 2360. As shown in Figure 23, an appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a substrate 2385. The substrate 2385 can include, for example, a flexible plastic, which can be configured in a thin film or as a mesh of no more than a few millimeters (mm) in thickness. For example, the substrate 2385 can be no more than 3 mm, or no more than 5 mm, thick depending on the embodiment. The substrate 2385 can include, for example, a flexible paper material. The substrate 2385 can include, for example, a composite material. The substrate 2385 can include, for example, one or more materials with properties such as durability, strength, cost, weight, bio-compatibility and disposability that are suitable for a given embodiment. As illustrated in Figure 23, the substrate 2385 is configured to irreversibly attach to the wound covering region 2300 of the wound dressing. For example, the substrate 285 can include an adhesive material on a face configured to conform to a surface of the wound dressing 2300. For example, the substrate 2385 can include one or more barbs, hooks or other projections on the face configured to conform to the surface of the wound dressing 2300.

Figure 23 depicts a fluid-activated voltaic cell 2360 attached to the substrate 2385. As described herein, a "fluid-activated voltaic cell" is an electrochemical cell that is configured to derive electrical energy from a spontaneous oxidation-reduction (redox) reaction that takes place within the cell when fluid is present within the cell. A fluid- activated voltaic cell includes at least two electrodes joined by an electrical connector.

The electrodes are located within an interior region of the fluid-activated voltaic cell. The electrodes are positioned with a space or a gap between the electrodes. When fluid from a wound dressing is present in the space, one electrode will be reduced and the other will be oxidized by contact with the fluid, which serves as an electrolyte. As shown in Figure 23, the fluid-activated voltaic cell 2360 includes a first electrode 2355 and a second electrode 2365 separated by space in an interior region 2375. A first electrode 2355 and a second electrode 2365 are fabricated from materials with different electrochemical properties, particularly different oxidation- reduction potentials. The materials fabricating the electrodes can be selected for their oxidation- reduction potentials in the presence of fluid. The materials fabricating two or more electrodes can be selected for their oxidation- reduction potentials in combination. For example, a first electrode can be fabricated from copper and a second electrode can be fabricated from lead. For example, a first electrode can be fabricated from zinc and a second electrode can be fabricated from copper. For example, a first electrode can be fabricated from copper and a second electrode can be fabricated from iron. For example, a first electrode can be fabricated from zinc and a second electrode can be fabricated from lead. For example, a first electrode can be fabricated from zinc and a second electrode can be fabricated from nickel. It has been estimated that electrochemical cells including different combinations of electrodes can produce voltages of approximately 0.5 V to approximately 1.7 V. See: Goodisman, "Observations on Lemon Cells," Journal of Chemical Education, vol. 78, no. 4, 516-518 (2001); Lee et al, "Water Activated Disposable and Long Shelf Life Microbatteries," 16th IEEE Micro Electro Mechanical Systems Conference, Kyoto, 19-23 January 2003; and Sammoura et al, "Water Activated Disposable and Long Shelf Life Microbatteries," Sensors and Actuators A 111 :79-86 (2004), which are each incorporated by reference herein. As shown in Figure 23, the interior region 2375 of the fluid-activated voltaic cell 2360 is positioned between the first electrode 2355 and the second electrode 2365 and configured to include a space within the interior region 2375 that can be occupied by fluid flow from the wound dressing. An electrical connector 2305, such as a wire, joins to the first electrode 2355 and the second electrode 2365. In some embodiments, the fluid- activated voltaic cell 2360 can include an anode and a cathode. The first electrode 2355 and the second electrode 2365 are positioned with the interior region 2375 between them and configured so that fluid from the wound dressing can flow into the interior region 2375.

Some embodiments include at least one enhancement unit 2370 positioned adjacent to one or both of the first and second electrodes 2355, 2365 within the fluid- activated voltaic cell 2360. An "enhancement unit" includes at least one chemical enhancer of the spontaneous redox reaction that takes place within the cell when fluid is present within the cell. The chemical enhancer promotes an electrochemical reaction within the fluid-activated voltaic cell 2360. The chemical enhancer of the voltaic cell is configured to be released when it contacts the fluid from the wound dressing, such as wound-related liquids, including blood and pus. In some embodiments, the enhancement unit includes at least one dry acid unit configured to release acid when contacted by a liquid. For example, the enhancement unit can include a dry or crystalline form of an acid, such as citric acid or ascorbic acid.

Some embodiments include at least one desiccant unit within the fluid-activated voltaic cell 2360. A "desiccant unit" includes one or more desiccant agents packaged as appropriate for the agent and embodiment. For example, at least one desiccant unit can be configured to reduce humidity within the interior region 2375 of the fluid-activated voltaic cell 2360. In some embodiments, at least one desiccant unit can be configured to form a region of low humidity within the interior region 2375 of the fluid-activated voltaic cell 2360. In some embodiments, at least one desiccant unit can be configured to encourage fluid flow into a region of low humidity within the interior region 2375 of the fluid- activated voltaic cell 2360 from a region of higher humidity, such as the interior of a moist wound dressing. In some embodiments, at least one desiccant unit can be configured to maintain a region of low humidity within the interior region 2375 of the fluid-activated voltaic cell 2360 during transport or storage of the appurtenance. For example, the at least one desiccant unit can be configured to maintain relatively low humidity within at least one enhancement unit 2370 positioned adjacent to one or both of the first and second electrodes 2355, 2365 within the fluid-activated voltaic cell 2360 prior to use of the appurtenance. A desiccant unit can be configured to produce a humidity gradient between a relatively humid interior of a moist wound dressing and a relatively dry interior region 2375 of the fluid-activated voltaic cell 2360. Such a humidity gradient can encourage fluid flow into the fluid-activated voltaic cell 2360 when sufficient fluid is present within the attached wound dressing.

Some embodiments include at least one humectant unit within the fluid-activated voltaic cell 2360. A "humectant unit" includes one or more desiccant agents packaged as appropriate for the agent and embodiment. In some embodiments, at least one humectant unit can be configured to encourage fluid flow into a region of low humidity within the interior region 2375 of the fluid-activated voltaic cell 2360 from a region of higher humidity, such as the interior of a moist wound dressing. A humectant unit can be configured to produce a humidity gradient between the interior of a moist wound dressing and the interior region 2375 of the fluid-activated voltaic cell 2360. Such a humidity gradient can encourage fluid flow into the fluid-activated voltaic cell 2360 when sufficient fluid is present within the attached wound dressing.

Also as illustrated in Figure 23, the appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a transmission unit 2380 attached to a surface of the substrate. The transmission unit 2380 includes circuitry 2330 and at least one antenna 2320. Although the transmission unit 2380 is illustrated as visible in Figure 23, in some embodiments all or part of the transmission unit 2380 will be covered and not be visible. For example, the transmission unit 2380 may be under a cover (e.g. 240 as illustrated in Figures 2A, 2B, 5A and 5B).

The transmission unit 2380 is configured to transmit a signal in response to power generated by the fluid-activated voltaic cell 2360. The transmission unit 2380 is configured to transmit a signal utilizing the power generated by the fluid-activated voltaic cell 2360. The transmission unit 2380 can be configured to respond to activation of the fluid-activated voltaic cell 2360. The transmission unit 2380 can be configured to transmit a signal in response to a current generated by the fluid-activated voltaic cell 2360. The transmission unit 2380 can be configured to transmit a signal in response to a voltage generated by the fluid-activated voltaic cell 2360. The transmission unit 2380 can be configured to transmit a signal in response to a voltage and a current generated by the fluid-activated voltaic cell 2360. Electrical power, including current and voltage, generated by the redox reaction in the fluid-activated voltaic cell 2360 powers signal transmission from the transmission unit 2380. One or more connectors 2395, such as wire, electrically connects the transmission unit 2380 and the fluid-activated voltaic cell 2360.

In some embodiments, a converter can be operably connected between the transmission unit 2380 and the fluid-activated voltaic cell 2360, connected with the one or more connectors 2395. In some embodiments, a current to voltage boost converter can be included along the connector 2395 between the transmission unit 2380 and the fluid- activated voltaic cell 2360. In some embodiments, a current to voltage step-up converter can be included along the connector 2395 between the transmission unit 2380 and the fluid-activated voltaic cell 2360. A converter can be operably attached to the fluid- activated voltaic cell 2360 and to the transmission unit 2380 with one or more connectors 2395.

As illustrated in Figure 23, an antenna 2320 can be a substantially planar antenna, such as commonly used in radio frequency identification (RFID) or near field

communication (NFC) units. The transmission unit 2380 can include a RFID unit. The transmission unit 2380 can include a NFC unit. The transmission unit 2380 can include a unique identifier, such as a RFID identifier, to specify a specific transmission unit 2380. Prior to use, the antenna 2320 can be detuned with a removable surface layer of a conductive material. This can be desirable to reduce excess RFID signals, for example from appurtenances 120 in storage prior to attachment to a wound dressing. See US Patent No. 7,724,136 to Posamentier, titled "Revealable RFID Devices," which is incorporated herein by reference. The circuitry 2330 of the transmission unit 2380 can include a variety of components, as desired in a particular embodiment. The circuitry 2330 of the transmission unit 2380 can include a processor 2335. The circuitry 2330 can include nonvolatile memory 2350. The circuitry 2330 can include a transmitter 2340. The circuitry 2330 can include one or more additional modules 2345. For example, the circuitry 2330 can include a receiver. For example, the circuitry 2330 can include a transceiver. For example, the circuitry 2330 can include an additional antenna. For example, the circuitry 2330 can include volatile memory. For example, the circuitry 2330 can include nonvolatile memory. The circuitry 2330 can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No.

7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates Having

Differing Dielectric Constant Values," which is incorporated herein by reference.

A transmission unit 2380 can be configured to transmit a signal in response to an interrogation signal. A transmission unit 2380 can include an energy harvesting unit, such as a unit configured to obtain energy from electromagnetic waves. A transmission unit 2380 can include a transponder utilizing electromagnetic waves, for example as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook:

Fundamentals and Applications in Contactless Smart Cards and Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference. A transmission unit 2380 can include an oscillator and encoder configured to generate a programmable pulse position-modulated signal in the radio frequency range. See, for example, US Patent No. 4,384,288 to Walton, titled "Portable Radio Frequency Emitting Identifier," which is incorporated herein by reference. A transmission unit 2380 can include a radio frequency identification device (RFID). A transmission unit 2380 can be configured to be a transmitter of signals in the UHF range. A transmission unit 2380 including an RFID device can be configured to transmit signals in the UHF standard range utilized in a global region, as illustrated in the "Worldwide RFID UHF Map" by

transmission unit 580 can include a radio frequency identification device (RFID). See, for example, Chawla and Ha, "An Overview of Passive RFID," IEEE Applications and Practice, 11-17 (September 2007), which is incorporated herein by reference. A transmission unit 2380 can include a battery-assisted passive RFID device, such as sold by Alien Technology®, Morgan Hill, CA, such as described in the brochure from Alien Technology® titled "Battery Assisted Passive Tags" and incorporated herein by reference. A transmission unit 2380 can include an optical transmitter unit. A transmitter unit can be configured to transmit at approximately 13.56 megahertz (MHz), or within the ISO 14443 standard parameters. See Patauner et al, "High Speed RFID/NFC at the Frequency of 13.56 MHz," presented at the First International EURASIP Workshop on RFID

Technology, pages 1-4, 24-25 September 2007, Vienna Austria, which is incorporated herein by reference. A transmission unit 2380 can include at least two antennas. A transmission unit 2380 can include a self-compensating antenna system. An antenna can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self-Compensating

Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference. A transmission unit 2380 can include a hybrid backscatter system configured to function in an RFID, IEEE 802.1 lx standard and Bluetooth system. See, for example, US Patent No. 7,215,976 to Brideglall, titled "RFID Device, System and Method of Operation Including a Hybrid backscatter-based RFID

Protocol Compatible with RFID, Bluetooth and/or IEEE 802.1 lx Infrastructure," which is incorporated herein by reference. A transmission unit 2380 can be configured to transmit at approximately 131 kilohertz (KHz), for example as part of a RuBee™ (IEEE standard 1902.1) system (sold, for example, by Visible Assets™, Inc.). See for example: the description of RuBee™ systems from the Visible Assets™ webpage; Stevens et al,

"RuBee (IEEE 1902.1) - The Physics Behind, Real-Time, High Security Wireless Asset Visibility Networks in Harsh Environments," a white paper from Visible Assets™; and in US Patent Application No. 2007/0171076 to Stevens and Waterhouse, titled "Low- frequency Radio Tag Encapsulating System," each of which are incorporated herein by reference. A transmission unit 2380 can include a near field communication (NFC) device. A transmission unit 2380 can include a Wireless Identification and Sensing Platform (WISP) device, manufactured by Intel Corporation, such as described in the "WISP: Wireless Identification and Sensing Platform" webpage (downloaded on October 28, 2011) incorporated herein by reference. A transmission unit 2380 can be operably coupled to a sensor, such as a sensor that detects changes in capacitance {see, e.g. Sample et al., "A Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which is incorporated herein by reference). In some embodiments, the transmission unit 2380 can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate 2385 and a surface of the wound dressing (e.g. surface 2210 as illustrated in Figure 22). In some embodiments, the transmission unit 2380 can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on a surface of the appurtenance 120. See, for example, US Patent Nos. 6,693,513 and

6,037,879 to Turtle, titled "Wireless Identification Device, RFID Device with Push- On/Push-Off Switch, and Method of Manufacturing Wireless Identification Device," and US Patent No. 6,863,220 to Selker, titled "Manually Operated Switch for Enabling and Disabling an RFID Card," as well as Sample et al., "A Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which are each incorporated herein by reference. A transmission unit 2380 can be operably coupled to a data storage unit, for example as described in US Patent No.

7,825,776 to Smith and Haehnel, titled "Device Configuration with RFID," and US Patent Application No. 2009/0243813 to Smith et al, titled "Wireless Programming of Non- Volatile Memory with Near-Field UHF Coupling," which are each incorporated herein by reference.

In some embodiments, the transmission unit 2380 can include an acoustic transmitter. For example, a transmission unit 2380 can include a piezoelectric speaker. A variety of suitable piezoelectric speakers are available, including from Murata

Manufacturing Co., Ltd., with North American corporate headquarters in Smyrna, GA (see, e.g. the Murata catalog titled "Piezoelectric Sounds Components" labeled P37E and dated January 28, 2010, which is incorporated herein by reference). Some embodiments can include acoustic transmitter units such as those manufactured by Advanced Telemetry Systems (headquartered in Isanti, MN) for the Pacific Northwest National Laboratory (see, e.g. JSATS Acoustic Transmitter information sheet from the Pacific Northwest National Laboratory, updated March 2010, which is incorporated herein by reference). In some embodiments, an appurtenance can include a piezoelectric speaker configured as part of an acoustic transmitter and also to act as a signaling device (e.g. to generate a beeping noise in response to a signal from the processor).

In some embodiments, the transmission unit 2380 can include an ultrasonic transmitter. In some embodiments, the transmission unit 2380 can include an ultrasonic transducer. Multiple examples of ultrasonic transmitters and transducers are commercially available, often marketed under the term "ultrasonic sensors" as it is used in the industry (see, e.g. the Murata catalog titled "Ultrasonic Sensor" labeled S15E and dated October 31 , 2008, which is incorporated herein by reference). The transmitter unit can be configured as part of an ultrasonic ranging system. See: Wang, "A Design Method of Ultrasonic Ranging System with High Accuracy," Journal of Computational Information Systems, 7: 7 pages 2444-2451 (2011), which is incorporated herein by reference. The transmission unit 2380 can be configured to communicate with an ultrasonic

communication system. See: Chen and Wu, "Ultrasonic System with Infrared

Communication Technology," Journal of Computers, vol. 6, no. 11, pages 2468-2475 (2011), which is incorporated herein by reference.

In some embodiments, the transmission unit 2380 can include an optical transmitter. For example, an optical transmitter unit can include one or more light emitting diodes (LEDs). For example, an optical transmitter unit can include an infrared laser. In some embodiments, optical transmitter units can be desirable to minimize interference from nearby electrical equipment, such as medical equipment. See:

Kavehrad, "Sustainable Energy-Efficient Wireless Applications Using Light," IEEE Communications Magazine, vol. 48, no. 12, pages 66-73, (2010); and Fadlullah and Kavehrad, "Indoor High-Bandwidth Optical Wireless Links for Sensor Networks" Journal of Lightwave Technology, vol. 28, no. 21, pages 3086-3094 (2010), which are incorporated herein by reference.

Some embodiments can include one or more additional transmission units distinct from the transmission unit 2380 attached to the fluid-activated voltaic cell 2360. An additional transmission unit can be configured to utilize received signals as an energy source. For example, an additional transmission unit can include a passive RFID unit. An additional transmission unit can include an attached power source, such as a battery. For example, an additional transmission unit can include, for example, an active RFID unit and an attached thin-film battery. An additional transmission unit including an RFID unit can be included, for example, as part of an inventory control device included with the appurtenance. An additional transmission unit including an RFID unit can be included, for example, as part of a patient identification system, such as implemented in a hospital or care facility. An additional transmission unit can be, for example, an optical energy emitter, such as an LED or other light emitting device. An additional transmission unit can be, for example, an auditory emitter, such as a piezoelectric speaker or other sound emitter. An additional transmission unit can be, for example, a vibration emitter, such as a piezoelectric device.

Figure 23 illustrates that the appurtenance 120 affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 includes a projection 200.

Although the projection 200 is displayed for the purposes of illustration, when an appurtenance 120 is affixed to a wound dressing to form a wound dressing- appurtenance combination unit 125 in normal use, the projection 200 would extend into an interior region of the wound dressing (see, e.g. Fig. 2B), and, therefore, not be visible from a superficial view. The projection 200 is configured to allow fluid flow from an interior region of the wound dressing into an interior region of the appurtenance 120. As illustrated in Figure 23, in some embodiments the projection 200 can include a

substantially hollow tubular structure. The projection 200 can be a substantially hollow tubular structure with an opening 2390 at the end distal to the appurtenance. The projection 200 can be of a size and shape to project underneath one or more superficial structures of the wound dressing when the wound dressing is in use. The projection 200 can be of a size and shape to project through a width of the wound dressing when the appurtenance is attached to the wound dressing. In some embodiments, the projection 200 is fabricated from a plastic material. For example, the projection 200 can be fabricated from a pliable plastic material. For example, the projection 200 can be fabricated from a bio-compatible plastic material. For example, the projection 200 can be fabricated from a plastic material that can be sterilized prior to use of the appurtenance 120. The projection 200 illustrated in Figure 23 includes an opening 2390 at the end of the projection 200 distal to the end of the projection 200 adjacent to the substrate 2385. The projection 200 can be of a size and shape to project from the outer surface of the wound dressing to within layers of the wound dressing. Figure 23 depicts a fluid-activated voltaic cell 2360 attached to the projection 200. The fluid-activated voltaic cell 2360 includes an internal region 2375. The projection 200 is configured to allow fluid flow from the interior of the wound dressing 2300 through the opening 2390 of the projection 200 into the internal region 2375 of the fluid-activated voltaic cell 2360. The projection 200 illustrated in Figure 23 includes a substantially hollow tube with a first aperture 2390 at a location adjacent to the interior region of the wound dressing and a second aperture at a location adjacent to the surface of the fluid-activated voltaic cell 2360. In some embodiments, there are a plurality of projections 200.

The wound dressing- appurtenance combination unit 125 is configured so that fluid from an interior region of a wound dressing can flow into the projection 200 through the opening 2390. Such fluid flow can occur, for example, when the wound dressing includes excessive levels of wound fluid (e.g. blood, pus) that moves into the projection 200 through the opening 2390 from capillary action or in response to a pressure difference between the interior of the wound dressing and the interior of the projection and the internal region 2375 of the fluid-activated voltaic cell 2360. The fluid-activated voltaic cell 2360 can include a chamber attached to a conduit, wherein the chamber is configured to receive the fluid from the external region. The fluid within the interior region 2375 of the fluid-activated voltaic cell 2360 serves as an electrolyte and activates the redox reaction of the electrodes 2355, 2365. The resulting current powers the transmission unit 2380 and initiates the sending of a signal from the transmission unit 2380. No electrical power from the redox reaction of the electrodes 2355, 2365 need be stored by the system, such as in the circuitry 2330. The current from the redox reaction of the electrodes 2355, 2365 directly powers the transmission unit 2380 at the same time as the redox reaction is occurring. It is expected that the current from the redox reaction of the electrodes 2355, 2365 will last for a brief time, on the order of minutes, and the signal transmitted from the transmission unit 2380 will similarly occur for a brief time. Therefore, the wound dressing- appurtenance combination unit 125 will generate a real-time signal that a wound dressing has excessive internal fluid, and therefore that it should be checked by a caregiver. In some embodiments, the signal from the wound dressing- appurtenance combination unit 125 is received by an external device that contains memory, and therefore can maintain a persistent indicator that the wound dressing requires attention. See, e.g. Figs. 30 and 31 and associated text.

Some embodiments include a sensor. A sensor can be operably attached, for example, to a projection 200. A sensor can be operably attached, for example, to a transmission unit 2380. A transmitter unit 2380 can be operably coupled to a sensor, such as a sensor that detects changes in capacitance (see, e.g. Sample et al, "A Capacitive

Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which is incorporated herein by reference). A transmitter unit 2380 can be operably coupled to a sensor, such as described in: Ruhanen et al, "Sensor-enabled RFID Tag and Handbook," from Building Radio Frequency Identification for the Global Environment (2008); Sample et al, "Design of an RFID-Based Battery-Free

Programmable Sensing Platform," IEEE Transactions on Instrumentation and

5,704,352 to Tremblay and Buckles, titled "Implantable Passive Bio-Sensor," which are each incorporated herein by reference. A sensor can be operably attached, for example, to a substrate 2385. A sensor can be operably attached, for example, to a fluid-activated voltaic cell 2360. "Sensors," as used herein, can be of a variety of types depending on the embodiment. One or more sensors can include at least one sensor responsive to changes in capacitance, or a measure of the ability of a configuration of materials to store electric charge. A general review of biosensors that detect changes in the dielectric properties of an electrode surface can be found in Berggren et al, "Capacitive Biosensors,"

Electroanalysis vol. 13, no. 3, 173-180, (2001), which is incorporated herein by reference. For example, one or more sensors can include a micromechanical biosensor with a fixed- fixed beam attached to an interdigitated capacitor (see, for example, Lim et al., "A

Micromechanical Biosensor with Interdigitated Capacitor Readout," Proceedings of the 2011 IEEE VICME International Conference on Complex Medical Engineering, May 22- 25, Harbin, China, which is incorporated herein by reference). Sensors can also include nanowire nanosensors, for example as described in Cui et al., "Nanowire Nanosensors for Highly Sensitive and Selective Detection of Biological and Chemical Species," Science, vol. 293, 1289-1292 (2001), which is incorporated herein by reference. Sensors can include those utilizing antibodies secured to a graphene substrate. See Tehrani et al, "Detection of Monoclonal Antibodies using Chemically Modified Graphite Substances," IEEE Sensors 2010 Conference Proceedings, 428-431, (2010), which is incorporated herein by reference. In some embodiments, sensors include aptamer-modified graphene field-effect transistors, see Ohno et al, "Graphene Field-Effect Transistors for Label-Free Biological Sensors," IEEE Sensors 2010 Conference Proceedings, 903-906, (2010), which is incorporated herein by reference. A sensor in an appurtenance can interact with a sensor present in a wound dressing, for example as described in US Patent No. 6,283,938 to McConnell, titled "Medicating Bandage and Controllable Permeable Membrane," which is incorporated herein by reference. A sensor can include a field effect transistor (FET), such as described in US Patent No. 7,507,675 to Zuilhof et al, titled "Device Manufacturing Method and Device," which is incorporated herein by reference. A sensor can include a nano-cantilever device, such as described in US Patent No. 7,612,424 to Espinosa and Ke, titled "Nanoelectromechanical Bistable Cantilever Device," which is incorporated herein by reference. A sensor can be configured to provide information regarding the wound dressing and associated fluid, such as temperature, presence of specific analytes in the fluid, or relative wetness of the dressing as a whole. A variety of sensors can be utilized in different embodiments of the appurtenances, depending on factors such as the intended use of the appurtenance, size, weight, cost, bio-compatibility, safety and ease of disposal.

Figure 24 depicts a wound dressing- appurtenance combination unit 125. The wound dressing- appurtenance combination unit 125 of Figure 24 is shown in a "top- down," external view, similar to that of Figure 23. As illustrated in Figure 24, the wound dressing- appurtenance combination unit 125 includes a wound dressing with a wound covering region 2300 and an edge region 2310. The appurtenance 120 includes a substrate 2385. The appurtenance 120 includes a transmission unit 2380. The transmission unit 2380 includes an antenna 2320 and circuitry 2330. A connector 2395 is configured to provide an electrical connection between the transmission unit 2380 and a fluid- activated voltaic cell 2360. The connector 2395 is configured to provide electrical current to the transmission unit 2380 from the fluid-activated voltaic cell 2360. The fluid-activated voltaic cell 2360 includes a first electrode 2355 and a second electrode 2365 joined with an electrical connector 2305, such as a wire. The electrical connector 2305 is joined to the connector 2395 to provide an electrical connection between the transmission unit 2380 and the fluid-activated voltaic cell 2360. The fluid-activated voltaic cell 2360 includes an internal region 2375 between the first electrode 2355 and a second electrode 2365, the internal region 2375 configured to accept fluid flow through the projection 200. The fluid- activated voltaic cell 2360 includes two enhancement units 2370 positioned adjacent to each of the first electrode 2355 and a second electrode 2365.

The projection 200 shown in Figure 24 includes a plurality of apertures 2390 A, B, C located along the length of the projection 200. Each of the apertures 2390 A, B, C will be positioned adjacent to a distinct region of the interior of the wound dressing when the projection 200 is inserted within the wound dressing (not shown in Figure 24 for purposes of illustration). Each of the apertures 2390 A, B, C is connected to a conduit 2400 A, B, C within the projection 200. Each conduit 2400 A, B, C includes a first end attached to an aperture 2390 A, B, C and a second end attached to the fluid activated voltaic cell 2360. Each of the conduits 2400 A, B, C is configured to direct fluid from the interior region of the wound dressing into the interior region 575 of the fluid-activated voltaic cell 2360. As shown in Figure 24, each of the conduits 2400 A, B, C projects into the interior region 575 of the fluid-activated voltaic cell 2360. In some embodiments, the projection 200 is partially positioned within the fluid-activated voltaic cell 2360 and the projection 200 includes an aperture within the fluid-activated voltaic cell 2360. Also as illustrated in Figure 24, in some embodiments the projection 200 includes a region 610 configured to facilitate insertion of the projection 200 into the wound dressing 2300. For example, the projection 200 can include a region 2410 configured as a tapered point on the distal end of the projection 200.

Some embodiments include a passive RFID unit including an identifier. In some embodiments, the passive RFID unit can be integrated into the transmission unit 2380. In some embodiments, the passive RFID unit can be a distinct unit of the appurtenance 120. The passive RFID can be configured, for example, as an positioning control unit to confirm the presence of the appurtenance 120 in a specific location, such as in association with a specific patient or wound dressing.

Figure 25 illustrates aspects of an embodiment of an appurtenance 120, such as that depicted in Figures 5 A and 5B. The appurtenance 120 depicted in a cross-sectional view in Figure 25 includes an enclosure 2500 of a height and width to fit substantially within an interior region of a wound dressing (see, e.g. Figure 5B). The appurtenance 120 depicted in a cross-sectional view in Figure 25 includes an enclosure 2500 of a height and width to fit substantially within an interior region of a wound dressing, the enclosure 2500 including at least one aperture 2510 A, B configured to allow fluid to flow from the interior region of the wound dressing into the enclosure 2500 (see dotted arrows). The appurtenance 120 depicted in Figure 25 also includes a fluid- activated voltaic cell 2360 attached to one or more of the at least one aperture 2510 A, B. The appurtenance 120 shown in Figure 25 includes a transmission unit 2380 attached to an internal surface of the enclosure 2500, the transmission unit 2380 including circuitry 2330 and at least one antenna 2330, the transmission unit 2380 configured to transmit a signal in response to the fluid-activated voltaic cell 2360. A wire connector 2395 connects the transmission unit 2380 to the fluid-activated voltaic cell 2360, the wire connector 2395 configured to conduct current from the fluid-activated voltaic cell 2360 to the transmission unit 2380. Some embodiments can include a passive RFID unit, including an identifier. The appurtenance 120 illustrated in Figure 25 includes an enclosure 2500 with substantially vertical walls tapering to an aperture 2510 A at a position corresponding to an interior region of a wound dressing when the appurtenance 120 is in use. A fluid-activated voltaic cell 2360 is positioned within the enclosure 2500 adjacent to the aperture 2510 A. The fluid-activated voltaic cell 2360 includes an opening 2320 A adjacent to the aperture 2510 A of the enclosure 2500. As shown in Figure 25, in some embodiments an enclosure 2500 includes a plurality of apertures 2510 A, 2510 B. Figure 25 illustrates a second aperture 2510 B in the wall of the enclosure 2500, the second aperture 2510 B connected to a conduit 2330. The conduit 2330 is connected to an opening 2320 B in the fluid-activated voltaic cell 2360 at an end of the conduit 2330 distal to the second aperture 2510 B.

Some embodiments include a microcapillary film within at least one aperture 2510

A, 2510 B, the microcapillary film configured to direct fluid from an interior region of the wound dressing into the interior of the enclosure 2500. See, for example, US Patent No. 6,420,622 to Johnston, "Medical Article Having Fluid Control Film," which is incorporated by reference herein. Some embodiments include a porous film or mesh within at least one aperture 2510 A, 2510 B, configured to allow fluid flow from an interior region of the wound dressing into the interior of the enclosure 2500 and to minimize other matter entering the appurtenance (e.g. structural portion of the wound dressing or wound debris).

The enclosure 2500 depicted in Figure 25 is a vertical, cross sectional view of a substantially cone shaped enclosure 2500. As shown in Figures 5A, 5B and 25, in some embodiments the enclosure 2500 is a substantially cylindrical structure, wherein the largest width of the substantially cylindrical structure is less than the smallest width of the wound dressing. In some embodiments, the enclosure 2500 is a substantially pyramidal structure, wherein the largest width of the substantially pyramidal structure is less than the smallest width of the wound dressing. In some embodiments, the enclosure 2500 includes a substantially conical or a substantially conical frustum shaped structure. In some embodiments, the enclosure 2500 includes a cross-sectional view square area (i.e.

substantially at right angles to the view illustrated in Figure 25) that is substantially equal to or less than one tenth of a square area of a largest surface of the wound dressing. As shown in Figure 25, the enclosure 2500 includes one or more flanges 2530 at the upper edge of the substantially conical structure of the enclosure 2500. The flanges 2530 are positioned to locate the enclosure 2500 relative to an outer surface of a wound dressing, and can be positioned to provide a surface for attachment of a cover 240 (see, e.g. Fig. 5B). A flange 2530 can include a flange region configured to cover part of an outer surface of the wound dressing when the appurtenance 120 is positioned for use with the wound dressing. One or more flanges 2530 can be located on the enclosure 2500 in a manner to functionally inhibit the movement of the enclosure 2500 into the interior of the wound dressing layer. The one or more flanges 2530 can be located on the enclosure 2500 in a manner to expand a portion of the circumference of the enclosure 2500 and prevent the appurtenance 120 from moving into the wound dressing beyond that expanded circumference. The enclosure 2500 can include one or more barbs positioned to hold the appurtenance 120 in place relative to the affixed wound dressing and to prevent the appurtenance 120 from slipping relative to the wound dressing. In some embodiments, the enclosure 2500 includes one or more walls, the walls forming a flange 2530 on an edge of the enclosure 2500, the flange 2530 positioned to attach a fastener between a surface of the wound dressing and the enclosure 2500. In some embodiments, the enclosure 2500 includes one or more walls, the walls forming a flange 2530 on an edge of the enclosure 2500, the flange 2530 including one or more projections from a surface of the flange 2530, the one or more projections positioned to pierce an outer surface of a wound dressing. For example, one or more flanges 2530 can include one or more barbs, points or projections positioned to pierce an outer surface of a wound dressing and assist in maintaining the position of the appurtenance relative to the wound dressing. In some embodiments, an enclosure 2500 can be formed as a substantially hollow tube.

Depending on the embodiment, the enclosure 2500 of the appurtenance 120 can be fabricated from a variety of materials. For example, the enclosure 2500 of the

appurtenance 120 can be fabricated from at least one plastic material. For example, the enclosure 2500 of the appurtenance 120 can be fabricated from bio-compatible materials. In some embodiments, the enclosure 2500 of the appurtenance 120 can be covered or coated to increase functionality. For example, the enclosure 2500 of the appurtenance 120 can be covered with bio-compatible materials on an external surface of the enclosure 2500. For example, the enclosure 2500 of the appurtenance 120 can be covered with a textured material to reduce potential slippage of the enclosure 2500 within a wound dressing (see Figure 5B).

Some embodiments include a fastener configured to form a seal between an edge of an enclosure 2500 and a surface of a wound dressing. For example, an edge of an enclosure 2500 can include an adhesive configured to seal the edge of the enclosure 2500 to a surface of the wound dressing. For example, as illustrated in Figure 25, the fastener can include a substantially planar cover 240 with an upper surface and a lower surface, the lower surface conforming to both the edge of the enclosure 2500 and to the surface of the wound dressing, and adhesive on at least a portion of the substantially planar cover 240. Some embodiments include a piercing region operably attached to an edge of the enclosure 2500 distal to an edge of the enclosure 2500 adjacent to an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. For example, the enclosure 2500 can include a tip, point, edge or surface projection configured to pierce a wound dressing surface when the appurtenance is affixed to the wound dressing.

Figure 25 also includes a fluid- activated voltaic cell 2360 attached to both of the apertures 2510 A, 2510 B in the enclosure 2500. The fluid- activated voltaic cell 2360 includes two electrodes 2355, 2365, electrically connected with a wire connection 2305. The first electrode 2355 and the second electrode 2365 are positioned with an interior region 2375 of the fluid- activated voltaic cell 2360 between them. In some embodiments, the fluid- activated voltaic cell 2360 includes at least one anode and at least one cathode. In some embodiments, the fluid- activated voltaic cell 2360 includes at least one enhancement unit 2370, the enhancement unit 2370 configured to release at least one chemical enhancer of an electrochemical reaction within the fluid-activated voltaic cell 2360 in response to contact with a fluid. In some embodiments, the at least one enhancement unit 2370 includes at least one dry acid unit configured to release acid when contacted by a liquid. The interior region 2375 of the fluid- activated voltaic cell 2360 is configured to receive fluid flow through the aperture 2510 A, B (illustrated as dotted arrows in Figure 25). In some embodiments, the fluid- activated voltaic cell 2360 includes a chamber configured to receive the fluid. As illustrated in Figure 25, the apertures 2510 A, 2510 B can be oriented adjacent to different regions of the wound dressing when the appurtenance 120 is in place, and therefore to sample any potential wound liquids present in the different regions of the wound dressing. In some embodiments with enclosures such as illustrated in Figure 25, there can be a second fluid-activated voltaic cell 2360 attached to at least one second aperture 2510 B, the at least one second aperture 2510 B configured to allow fluid to flow from a second interior region of the wound dressing into an interior of the second fluid-activated voltaic cell 2360. See also Figure 26. Some embodiments can include a sensor attached to at least one aperture 2510 A, 2510 B of the enclosure 2500, and a connection between the sensor and the transmission unit 2380. For example, the sensor can be operably coupled to the electrochemical circuit formed by the fluid-activated voltaic cell 2360 and the transmission unit 2380, so that the sensor is activated by current from the fluid-activated voltaic cell 2360. For example, there may be a wire connection between the sensor and the transmission unit 2380.

Figure 26 illustrates an appurtenance 120 attached to a wound dressing 2300, 2310 and forming an appurtenance affixed to a wound dressing combination unit, 125. The view of Figure 26 is similar to those of Figures 23 and 24. The appurtenance 120 shown in Figure 26 includes a substrate 2385. The appurtenance 120 includes two projections 200 A, 200 B. The projections 200 A, 200 B are positioned at different faces of the appurtenance 120. The projections 200 A, 200 B are of different lengths and project at different angles (e.g. the angle shown as Θ in Figures 2 A and 2 B) from the plane of the substrate 2385 of the appurtenance 120. Each of the individual projections 200 A, 200 B includes an opening 2390 A, 2390 B. Each of the openings 2390 A, 2390 B is positioned to be adjacent to a different region of the interior of the wound dressing 2310. The individual projections 200 A, 200 B can, therefore, be considered to be sampling different regions of the interior of the wound dressing 2310 when the appurtenance affixed to a wound dressing combination unit, 125 is in use.

Some embodiments include a microcapiUary film within at least one opening 2390

A, 2390 B, the microcapiUary film configured to direct fluid from an interior region of the wound dressing into the interior of the projection 200. See, for example, US Patent No. 6,420,622 to Johnston, "Medical Article Having Fluid Control Film," which is

incorporated by reference herein. Some embodiments include a porous film or mesh within at least one opening 2390 A, 2390 B, configured to allow fluid flow from an interior region of the wound dressing into the interior of the projection 200 and to minimize other matter entering the appurtenance (e.g. structural portion of the wound dressing or wound debris). Each of the projections 200 A, 200 B illustrated in Figure 26 is operably attached to a fluid-activated voltaic cell 2360 A, 2360 B. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes a first electrode 2355 and a second electrode 2365 connected with a wire connection 2305. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes an interior region 2375 between the first electrode 2355 and the second electrode 2365. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes an enhancement unit 2370 adjacent to each of the electrodes 2355, 2365. A wire connector 2395 couples the fluid-activated voltaic cells 2360 A, 2360 B to a single transmission unit 2380. The transmission unit includes circuitry 2330 and an antenna 2320.

In the embodiment illustrated in Figure 26, a fluid, such as blood or pus, present in the region of the wound dressing adjacent to either of the respective projection 200 A, 200 B openings 2390 A, 2390 B would flow into the projection 200 A, 200 B through the respective opening 2390 A, 2390 B. The presence of liquid in the interior region 2375 between the first electrode 2355 and the second electrode 2365 acts as an electrolyte for the electrochemical reaction of the respective fluid-activated voltaic cell 2360 A, 2360 B. Current generated by the electrochemical reaction would move through the wire connector 2395 and into the transmission unit 2380, activating the transmission unit 2380.

Therefore, in the conformation illustrated in Figure 26, excess liquid from the wound dressing in either the region of the wound dressing adjacent to either of the respective projection 200 A, 200 B openings 2390 A, 2390 B would initiate the electrochemical reaction of the respective fluid-activated voltaic cell 2360 A, 2360 B, resulting in a signal being generated by the transmission unit 2380.

Figure 27 illustrates an appurtenance 120 to a wound dressing. The appurtenance 120 includes a substrate 2385 and two projections, 200 A, 200 B, projecting from different sides of the substrate 2385. As in Figure 26, the embodiment illustrated in Figure 27 includes projections, 200 A, 200 B of different lengths and angles (e.g. the angle shown as Θ in Figures 2 A and 2 B) from the plane of the substrate 2385 of the appurtenance 120. Therefore, the embodiment shown in Figure 27 would sample fluid potentially present in different regions of a wound dressing. The different regions of a wound dressing can be vertically or horizontally in different planes of the wound dressing, or both. Each of the projections 200 A, 200 B is connected to its respective fluid-activated voltaic cell 2360 A, 2360 B. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes a first electrode 2355 and a second electrode 2365 connected with a wire connection 2305. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes an interior region 2375 between the first electrode 2355 and the second electrode 2365. Each of the fluid-activated voltaic cells 2360 A, 2360 B includes an enhancement unit 2370 adjacent to each of the electrodes 2355, 2365. A wire connector 2395 couples each of the fluid-activated voltaic cells 2360 A, 2360 B to a distinct transmission unit 2380 A, 2380 B. Each of the respective transmission units 2380 A, 2380 B includes circuitry 2330 and an antenna 2320. Each of the respective transmission units 2380 A, 2380 B is configured to transmit a signal in response to a current generated by a redox reaction in the attached fluid- activated voltaic cell 2360 A, 2360 B.

In the embodiment illustrated in Figure 27, a fluid, such as blood or pus, present in the region of the wound dressing adjacent to either of the respective projection 200 A, 200 B openings 2390 A, 2390 B would flow into the projection 200 A, 200 B through the respective opening 2390 A, 2390 B. The presence of liquid in the interior region 2375 between the first electrode 2355 and the second electrode 2365 acts as an electrolyte for the electrochemical reaction of the respective fluid-activated voltaic cell 2360 A, 2360 B. Current generated by the electrochemical reaction would move through the wire connector 2395 and into the associated transmission unit 2380 A, 2380 B, activating the specific transmission unit 2380 A, 2380 B. Therefore, in the conformation illustrated in Figure 27, excess liquid from the wound dressing in either the region of the wound dressing adjacent to either of the respective projection 200 A, 200 B openings 2390 A, 2390 B would initiate the electrochemical reaction of the respective fluid-activated voltaic cell 2360 A, 2360 B, resulting in a signal being generated by the specific transmission unit 2380 A, 2380 B. In a system wherein a signal transmitted from a specific transmission unit 2380 A, 2380 B could be distinguished from other potential signals, the region of the wound dressing from which the fluid was obtained can also be associated with the specific signal. Such information can be useful, for example, to specify the relative depth or width of the wound dressing where the fluid was present. Such information can be useful, for example, to specify if the fluid is widespread in the wound dressing (i.e. present in multiple locations).

Figure 28 depicts an appurtenance 120 to a wound dressing. The appurtenance 120 includes a substrate 2385. As illustrated in Figure 28, the appurtenance 120 includes a plurality of conduits 2800 A, B, C, D, E, F configured to direct fluid from a plurality of regions of a wound dressing adjacent to the appurtenance 120. Although the appurtenance 120 is illustrated in Figure 28 as substantially planar, in some embodiments the appurtenance can include other three dimensional structures, such as cones, ellipses, cylinders, or a combination of shapes. An appurtenance 120 can include one or more surfaces configured to mate with one or more surfaces of a wound dressing (not illustrated in Figure 28). Each of the plurality of conduits 2800 A, B, C, D, E, F is positioned to allow fluid from an adjacent region of a wound dressing to flow through the conduit 2800

A, B, C, D, E, F into the attached fluid-activated voltaic cell 2360 A, B, C, D, E, F. A conduit 2800 A, B, C, D, E, F can include features configured to encourage the flow of fluid from an adjacent region of a wound dressing to flow through the conduit 2800 A, B,

C, D, E, F. For example, a conduit 2800 A, B, C, D, E, F can include a plurality of microchannels configured to direct fluid flow from the exterior of the appurtenance 120 into the fluid-activated voltaic cell 2360 A, B, C, D, E, F. See, for example, US Patent No. 6,420,622 to Johnston, "Medical Article Having Fluid Control Film," which is incorporated by reference herein. For example, one or more of the conduits 2800 A, B, C,

D, E, F can include a projection extending into the region surrounding the appurtenance, the projection configured to direct fluid flow from the exterior of the appurtenance 120 into the fluid-activated voltaic cell 2360 A, B, C, D, E, F. No projections are illustrated in Figure 28, however examples are, inter alia, in Figs. 2A, 2B, 23, 24, 26, 27 and 30. Each of the fluid-activated voltaic cells 2360 A, B, C, D, E, F has an attached transmission unit 2380 A, B, C, D, E, F. Each of the transmission units 2380 A, B, C, D, E, F is configured to transmit a signal in response to current generated by the attached fluid-activated voltaic cell 2360 A, B, C, D, E, F. In some embodiments, each of the transmission units 2380 A,

B, C, D, E, F transmits a distinct signal, i.e. a signal including a unique identifier of that transmission unit 2380 A, B, C, D, E, F. The respective location(s) in the wound dressing with fluid flowing into the conduits 2800 A, B, C, D, E, F can, therefore, be derived from the distinct signal from generated by each of the transmission units 2380 A, B, C, D, E, F.

Figure 29 depicts an appurtenance 120 to a wound dressing. The appurtenance 120 includes a substrate 2385. As illustrated in Figure 29, the appurtenance 120 includes a plurality of conduits 2900 A, B, C, D, E, F configured to direct fluid from a plurality of regions of a wound dressing adjacent to the appurtenance 120. Although the appurtenance 120 is illustrated in Figure 29 as substantially planar, in some embodiments the appurtenance can include other three dimensional structures, which can include a combination of curvilinear structures. An appurtenance 120 can include one or more surfaces configured to mate with one or more surfaces of a wound dressing (not illustrated in Figure 29). Each of the plurality of conduits 2900 A, B, C, D, E, F is positioned to allow fluid from an adjacent region of a wound dressing to flow through the conduit 2900 A, B, C, D, E, F into the attached fluid-activated voltaic cell 2360 A, B, C, D, E, F. A conduit 2900 A, B, C, D, E, F can include features configured to encourage fluid from an adjacent region of a wound dressing to flow through the conduit 2900 A, B, C, D, E, F. For example, a conduit 2900 A, B, C, D, E, F can include a plurality of microchannels configured to direct fluid flow from the exterior of the appurtenance 120 into the fluid- activated voltaic cell 2360 A, B, C, D, E, F. See, for example, US Patent No. 6,420,622 to Johnston, "Medical Article Having Fluid Control Film," which is incorporated by reference herein. For example, one or more of the conduits 2900 A, B, C, D, E, F can include a projection extending into the region surrounding the appurtenance, the projection configured to direct fluid flow from the exterior of the appurtenance 120 into the fluid- activated voltaic cell 2360 A, B, C, D, E, F. No projections are illustrated in Figure 29, however examples are, inter alia, shown in Figs. 2A, 2B, 23, 24, 26, 27 and 30.

As illustrated in Figure 29, each of the fluid-activated voltaic cells 2360 A, B, C,

D, E, F is attached to a transmission unit 2380 with a wire connector 595 A, B, C, D, E, F. The transmission unit 2380 includes an antenna 2320 and circuitry 2330. The

transmission unit 2380 is configured to send a signal in response to a current transmitted through one or more of the associated wire connectors 2395 A, B, C, D, E, F from one or more of the fluid-activated voltaic cells 2360 A, B, C, D, E, F. The transmission unit 2380 of the appurtenance 120 illustrated in Figure 29 is configured to send a series of signals in response to current generated by the fluid-activated voltaic cells 2360 A, B, C, D, E, F in series. For example, the transmission unit 2380 may be activated at a first time in response to a current generated by fluid-activated voltaic cell 2360 A and carried by the wire connector 2395 A from the fluid-activated voltaic cell 2360 A to the transmission unit 2380. For example, the transmission unit 2380 may be activated at a second time in response to a current generated by fluid-activated voltaic cell 2360 B and carried by the wire connector 2395 B from the fluid-activated voltaic cell 2360 B to the transmission unit 2380. For example, the transmission unit 580 may be activated at a third time in response to a current generated by fluid-activated voltaic cell 2360 C and carried by the wire connector 2395 C from the fluid-activated voltaic cell 2360 C to the transmission unit 2380. The transmission unit 580 at further times can be activated by, for example, in response to current generated by fluid-activated voltaic cells 2360 D, E and F. Figure 30 illustrates an appurtenance 120 attached to a wound dressing 1 15 to form a wound dressing with an affixed appurtenance combination unit 125. The wound dressing with an affixed appurtenance combination unit 125 shown in Figure 30 is illustrated in cross-section, similar to the views of Figure 2 A and 2B. The wound dressing with an affixed appurtenance combination unit 125 includes a wound dressing portion including an outer layer 210 and a wound dressing layer 220. A cover 240 further adheres to the outer surface of the outer layer 210 and to an outer surface of the appurtenance 120.

The appurtenance 120 includes a plurality of projections 200 A, B, C, D and E. Each projection 200 A, B, C, D and E is configured to allow fluid flow from an adjacent region of the wound dressing interior, as illustrated by the dotted arrows. As shown in

Figure 30, the projections 200 A, B, C, D and E are spaced apart, so that they extend from different positions on the appurtenance 120. In addition, the projections 200 A, B, C, D and E are of different lengths. The projections 200 A, B, C, D and E also extend from the surface of the appurtenance at different angles, θι, θ₂, θ₃, θ₄, θ₅. The combination of projections 200 A, B, C, D and E spaced apart on the appurtenance 120, of different lengths and extending at different angles, θι, θ₂, θ₃, θ₄, θ₅ results in an appurtenance 120 that is configured to sample fluid from a significant portion of the interior of the appurtenance 120. The configuration of projections 200 A, B, C, D and E spaced apart on the appurtenance 120, of different lengths and extending at different angles, θι, θ₂, θ₃, θ₄, θ₅ results in an appurtenance 120 that can sample fluid present in different regions and layers of the wound dressing layer 220. The plurality of projections 200 A, B, C, D and E can each be attached to an individual fluid-activated voltaic cell which are in turn connected to individual transmission units (e.g. as illustrated in Figure 28). The plurality of projections 200 A, B, C, D and E can each be attached to an individual fluid-activated voltaic cell which are all connected to one transmission unit (e.g. as illustrated in Figure 29). The plurality of projections 200 A, B, C, D and E can each be attached to a single fluid-activated voltaic cell connected to a corresponding transmission unit (see Figure 25). There can be combinations of projections attaching to the same or different fluid-activated voltaic cells, which can in turn be attached to one or more transmission units. A plurality of projections 200 A, B, C, D and E included on a single appurtenance can be of varying shapes, sizes, and widths. A plurality of projections 200 A, B, C, D and E included on a single appurtenance can be configured to allow fluid flow through the projections at different rates, for example with conduits of different internal dimensions. A configuration of projections including projections of varying lengths, varying positional spacing, and extending at different angles can be configured to sample different regions of a wound dressing. Various configurations can be utilized for particular medical monitoring requirements. For example, one or more projections can be configured to extend into a region of the wound dressing adjacent to a periwound region to monitor fluid in that region of the dressing. A caregiver may wish to maintain low moisture content in the region of the wound dressing adjacent to the periwound region, for example to minimize maceration and associated tissue damage. In such a situation, an appurtenance with multiple projections of a size and shape to extend into the region of the specific wound dressing adjacent to the periwound region for a particular patient can be selected. If fluid becomes abundant in the region of the wound dressing adjacent to the periwound region, the fluid will flow through the projection and act as an electrolyte in an attached fluid-activated voltaic cell. The resulting current will activate a transmission unit attached to the attached fluid-activated voltaic cell, resulting in a signal transmission and subsequent notification of a caregiver that the wound dressing should be manually checked. For example, an appurtenance with a plurality of projections of different discrete lengths can be utilized to sample fluid potentially present at different horizontal levels of a wound dressing. A caregiver may wish to be notified sequentially of the level of fluid present in a particular deep dressing, for example if a wound bleeds through the entire depth of the dressing over time. An appurtenance with a plurality of projections of different discrete lengths can be utilized to monitor fluid potentially present in the different layers, and to utilize current generated from a plurality of fluid-activated voltaic cells to power one or more transmission units over time. Information from the resulting series of signals (e.g. time of receipt, time between signals, elapsed time from wound dressing application) can be stored in memory at a remote unit for processing and notification of a caregiver. For more general monitoring of fluid presence in a wound dressing, an appurtenance with a plurality of projections spaced apart on the appurtenance, the projections of different lengths and extending at different angles (e.g. as illustrated in Figure 30) can be employed to monitor a majority of the interior region of the wound dressing.

Figure 31 illustrates aspects of a local unit 1810. As shown in Figure 31 , a local unit 1810 includes a display unit 1820 and a input device 1830. A user 1820 operates the local unit 1810. The local unit 1810 includes circuitry for accepting a signal from an appurtenance attached to a wound dressing 3100. The local unit 1810 includes circuitry for processing a signal from an appurtenance attached to a wound dressing 3110.

In some embodiments, an appurtenance to a wound dressing includes an appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow fluid flow from an interior region of a wound dressing into the appurtenance; a fluid- activated voltaic cell including an internal chamber, the internal chamber attached to the conduit; and a radio frequency identification (RFID) unit attached to the fluid- activated voltaic cell and configured to operate in response to current generated by the fluid- activated voltaic cell. The internal chamber can be configured to receive the fluid flowing through the conduit. The conduit can include a plurality of microchannels configured to direct fiuid flow into the fluid- activated voltaic cell. See, for example, US Patent No. 6,420,622 to Johnston, "Medical Article Having Fluid Control Film," which is incorporated by reference herein. The RFID unit can include a unique identifier for that unit. The RFID unit can include an antenna, and circuitry configured to initiate signal transmission from the antenna. The RFID unit can include a processor. Some embodiments also include a second conduit positioned to allow fluid flow from a second interior region of a wound dressing into the appurtenance; and a second fluid- activated voltaic cell including an internal chamber, the internal chamber attached to the second conduit, wherein the second fluid- activated voltaic cell is configured to direct current to the RFID unit. Some embodiments also include a sensor attached to the conduit; and a connector between the sensor and the RFID unit.

A method of monitoring a wound includes the steps of: conveying fiuid from an interior region of a wound dressing to an appurtenance of the wound dressing; placing the fluid adjacent to a first electrode and a second electrode of a fluid- activated voltaic cell integral to the appurtenance; and utilizing current received from the fluid-activated voltaic cell directly to send a wireless signal beyond the appurtenance. For example, a transmission unit connected to the fluid- activated voltaic cell integral to the appurtenance can send a wireless signal beyond the appurtenance in response to the current generated by the fluid- activated voltaic cell.

With reference now to Figure 32A, illustrated is a body part 3210 that is a human leg. The body part 3210 includes a wound region, denoted by the dotted circle. The wound region includes a cavity wound 3200, denoted by the X marking in Figure 32A. A "cavity wound," as used herein, denotes a wound that penetrates into body tissue and is of a size and shape to create a cavity or space in the tissue with an open region at the normal tissue surface. A cavity wound includes a loss of continuity of the skin with associated tissue loss. A cavity wound involves the dermal skin layer, and can, in some circumstances, extend into sub-dermal layers of skin to expose underlying tissues, such as tendon, muscle and bone. For example, a cavity wound can include an edge region at the skin level of an individual and penetrate into the adjacent skin and tissue layers, with the wound forming a cavity adjacent to the normal skin level. A cavity wound can be created by traumatic injury, such as a puncture of the skin and tissue. For example, a cavity wound can be created by an open reduction of fracture. A cavity wound can be formed from a severe burn, such as a third degree burn. A cavity wound can be formed by surgical intervention, for example to remove a tumor or other tissue mass, such as an area of infected tissue. A cavity wound can be partially formed or enlarged by debridement of a wound by surgical or chemical means. A cavity wound can be formed by tissue atrophy or necrosis at a site of low blood flow in the tissue. For example, a cavity wound can develop from a pressure ulcer, decubitus ulcer or bedsore that increases in severity due to a lack of blood flow to a region due to physical pressure on the circulatory system in the tissue and shear stress on the tissue structure. For example, a cavity wound can develop from a diabetic ulcer, a venous ulcer, or an arterial ulcer. For example, a cavity wound can develop from a stage 2-4 pressure ulcer. For example, a cavity wound can develop from necrotizing fasciitis. A cavity wound can arise from a wound closing by secondary or tertiary intention. A cavity wound can be a "chronic wound," or a persistent wound that resists healing over a normal time frame. A cavity wound can form from a non-healing surgical wound. A cavity wound can heal normally, such as with granulation of the wound bed over a clinically-expected time frame.

The temperature adjacent to the wound bed of a cavity wound depends on the physiological conditions of the cavity wound, including wound location, position and depth, regional blood flow, inflammation, and immune system response. In some patients, for example, the temperature within the cavity of a cavity wound can be in a range between 35 degrees Centigrade and 40 degrees Centigrade. Temperatures below 35 degrees Centigrade and above 40 degrees Centigrade can indicate a medical situation relative to the cavity wound. For example, a temperature of approximately 30 degrees Centigrade within a cavity wound can indicate insufficient blood flow to the adjacent tissue, or excessive necrotic tissue within the cavity wound. For example, a temperature above approximately 40 degrees Centigrade can indicate a localized immune response, and therefore, an infection within the cavity wound region. A change in temperature over time within a cavity wound can indicate the deterioration or improvement of the medical situation of the cavity wound.

Physical pressure on a wound surface of a cavity wound can have negative effects on a cavity wound, including physical shear of the wound surface and compression of blood vessels in the periwound region. The specific physical pressure that can be acceptable for a patient in a cavity wound depends on a number of factors, including wound size, location, patient health and secondary factors, such as additional wounds or medical conditions. As an example, the minimal physical pressures required to close a capillary range from 12 to 32 mm Hg. See: Clay, "Preventing Pressure Ulcers in your Facility: Karen S. Clay, R , BSN, CWCN, Presents a Primer on How to Protect Frail Residents— and Avoid Costly Reprimands," HCPro, Inc., (2004) (downloaded on

December 6, 2012); and Bluestein and Javaheri, "Pressure Ulcers: Prevention, Evaluation, and Management," American Family Physician 78(10): 1186-1196 (2008), which are each incorporated herein by reference. Generally, medical intervention for cavity wounds includes physical pressures of less force than would be expected to close an adjacent capillary. For example, in some situations a medical intervention, such as a wound dressing, would be preferred by a caregiver that is predicted to press with a force of less than 32 mm Hg at the wound surface during use with the cavity wound, in order to maximize blood flow in the region and to promote healing of the cavity wound. For example, in some situations a medical intervention, such as a wound dressing, would be preferred by a caregiver that is predicted to press with a force of less than 20 mm Hg at the wound surface during use with the cavity wound, particularly in medical situations wherein the wound surface is considered to be sensitive or fragile {e.g. directly after surgery or injury). For example, in some situations a medical intervention, such as a wound dressing, would be preferred by a caregiver that is predicted to press with a force of less than 12 mm Hg at the wound surface during use with the cavity wound, for example with wounds that are considered to be particularly high risk due to ongoing lack of healing, or the patient's overall medical status.

A cavity wound has a "periwound" region, which refers to the tissue in a region adjacent to the cavity wound. For example, the periwound region refers to the tissue area directly adjacent to the cavity wound. Tissue in the periwound region can be affected by the cavity wound, for example through inflammation, swelling, infection, low oxygen perfusion, or wound-associated trauma (e.g. bruising). In some situations, the periwound region includes wound exudate, or wound fluid arising from the cavity wound.

Cavity wounds such as described herein are usually clinically resolved by secondary intention or tertiary intention. Clinical protocols for the healing of cavity wounds can include leaving the cavity space open or uncompressed, with the addition of a wound dressing that fully or partially fills the cavity space, minimizes potential exposure of the wound surface to external debris, and reduces potential dryness at the wound surface. A cavity wound dressing can also be configured to absorb excess exudate from the wound region. Primary and secondary dressings on cavity wounds are designed to be put in place for a limited time period, such as hours or days, and then replaced. For example, depending on the clinical situation, a cavity wound primary and secondary dressing can be intended for replacement every 6 hours, every 12 hours, every 24 hours, daily, every 2 days, every 3 days, every 4 days, every 5 days, every 6 days, or every week. As an example, some cavity wounds are filled with saline-soaked gauze bandages as a primary dressing, and then covered with an adhesive cover over the wound region as a secondary dressing. The saline-soaked gauze bandages are then removed and replaced on a regular schedule, such as every day, every 2 days, or every 3 days, every 4 days, every 5 days, every 6 days, or every week. In some situations, cavity wound dressings include alginate dressings, such as Sorbsan® and Kaltostat® wound dressings. In some situations, cavity wound dressings include foam-based dressings, such as Cavi-Care®, Allevyn® Plus Cavity and PolyMem® Wic® wound dressings. Cavity wound dressings can also include gel or alginate based dressings for topical application to the wound surface.

Cavity wound dressings such as those described herein are generally used for a relatively short period of time, on the order of hours or days. Solid wound dressings can be removed and disposed of after use. An appurtenance configured for use with a cavity wound dressing, such as those described herein, is configured for use over the course of hours or days and then removed and disposed of using standard methods. A cavity wound dressing and an associated appurtenance are generally single use and disposable after use. For example, a caregiver can require a new cavity wound dressing every 24 hours (1 day) for an acute wound. Any cavity wound primary and secondary dressing utilized in this type of situation would, consequently, be of a size and shape to remain within the wound cavity and affixed to the periwound region over the course of at least a 24 hour period and then removed for disposal. An appurtenance to a cavity wound dressing intended for use over the course of a 24 hour time period should similarly be of a size, shape, material fabrication, and capabilities to function while affixed to or used in conjunction with the cavity wound dressing over the 24 hour period that the dressing is in use. As an additional example, a caregiver can decide that for another type of cavity wound, such as a chronic wound, the cavity wound dressing needs to be removed and replaced, once every 3 days, or every 4 days, or every 5 days, or every 6 days, or every 7 days. Correspondingly, an appurtenance affixed to or used in conjunction with a cavity wound dressing intended for use over the course of at least 3 to 7 days should be of a size, shape, material fabrication, flexibility, mass and capabilities to function while associated with the cavity wound dressing over at least the 3 to 7 day period that the dressing is in use. In embodiments wherein an appurtenance is intended for reuse, such as reuse with a second or subsequent cavity wound dressing used over a wound, the appurtenance should be of a size, shape, material fabrication, flexibility, mass and capabilities to function during the entire intended use, including the time period of removal from a first cavity wound dressing and application with a second cavity wound dressing. An appurtenance is durable for the intended time and conditions of use. An appurtenance is fabricated to retain its structural integrity and not chip, split, peel or fragment while in use within the cavity wound.

A caregiver can utilize some embodiments of the appurtenances and related systems described herein in relation with multiple types of cavity wound dressings. As used herein, a caregiver includes at least one of a patient, a personal caregiver, a healthcare provider, and medical personnel. Appurtenances can be fabricated in shapes and sizes to conform to a variety of standard cavity wound dressing sizes, shapes and types. Appurtenances can be fabricated with, for example, transmission units, antennas and sensors appropriate for use with a variety of cavity wound dressings. Appurtenances can be fabricated with, for example, transmission units, antennas and sensors appropriate for different medical situations and monitoring requirements. While it is envisioned that every appurtenance will not be appropriate for use with every cavity wound dressing (for example due to size, shape or material compatibility), a given appurtenance is expected to be suitable for use with a range of potential cavity wound dressings. For example, a given appurtenance of a specific size, shape and fabrication, including type of senor unit(s), should be suitable for use with a variety of cavity wound dressings of conforming sizes, shapes and types. Generally, any specific appurtenance embodiment is not expected to only conform to use with a unique cavity wound dressing of a specific size, shape and type. Instead, it is expected that a specific appurtenance embodiment will be suitable for use with a range of cavity wound dressings. Similarly, it is expected that a specific appurtenance embodiment will be suitable for use with a range of cavity wound and cavity wound dressing monitoring requirements.

In reference now to Figure 32B, illustrated is a cross-section view through a wound region including a cavity wound 3200. The cavity wound 3200 is within the body part 3210, such as illustrated with an external view in Figure 32A. The cavity wound 3200 shown in Figure 32B is depicted as a substantially oval cavity for purposes of illustration, however actual cavity wound sizes and shapes will vary. The cavity wound 3200 includes a cavity 3220 or space in the tissue of the body part 3210. The cavity wound 3200 also includes a wound surface 3230 which encompasses the tissue surface of the wound 3200 facing the cavity 3220. The wound 3200 can be a partial or full thickness wound.

Depending on the depth and location of a cavity wound 3200 on a body part 3210, a cavity 3220 can extend into multiple layers of tissue, and potentially through different types of tissue. For example, a cavity 3220 of a pressure ulcer wound can extend through epithelial layers, a muscular layer, and to a bone surface. For example, a stage four pressure ulcer can extend to the bone. Correspondingly, a wound surface 3230 includes tissues representative of the respective layers that the cavity 3220 extends through. A cavity wound 3200 healing by secondary intention is likely to granulate from the wound surface 3230 inward, such as from the deepest cavity level to the surface level, with a

corresponding decrease in size of the cavity 3220 over time. A cavity wound 3200 has a surface region 3240 of the periwound region. For example, the surface region 3240 of the periwound region can include the external skin level adjacent to the cavity wound 3200. During treatment, a wound dressing cover can be adhered to the surface region 3240 of the periwound region of the cavity wound 3200.

Figure 33A depicts an appurtenance 3330 to a cavity wound dressing. The appurtenance 3330 to a cavity wound dressing shown in Figure 33 A is a substantially planar, disk-like structure. The appurtenance 3330 is separate and distinct from a cavity wound dressing, but intended for functional use with a primary, and in some

embodiments, a secondary wound dressing for a cavity wound. The appurtenance 3330 embodiment illustrated in Figure 33 A is intended for use in combination with a cavity wound dressing, and not intended for use without a wound dressing. In some

embodiments, an appurtenance 3330 can be attached to a dressing for a cavity wound. For example, the appurtenance 3330 can be attached to a dressing for a cavity wound with a chemical attachment, such as a pressure-sensitive adhesive, a contact adhesive, or a quick- drying adhesive. For example, the appurtenance 3330 can be attached to a dressing for a cavity wound with a mechanical attachment. For example, a mechanical attachment can include attachments shaped like prongs, barbs, bristles, spikes, or spurs on a cavity-facing surface of the appurtenance 3330. In some embodiments, an appurtenance 3330 can be stabilized relative to a dressing for a cavity wound. For example, an appurtenance can be tethered or affixed to a cavity wound dressing in a manner sufficient to stabilize the appurtenance 3330-wound dressing combination. In some embodiments, an appurtenance 3330 can be configured for use in conjunction with, but not attached to, a cavity wound primary or secondary dressing. An appurtenance 3330, like a cavity wound primary dressing, can be of different sizes and shapes corresponding to use in different size and shape cavity wounds .

The appurtenance 3330 illustrated in Figure 33 A includes a substantially planar, disk- like substrate 3300. A substrate 3300 such as illustrated in Figure 33 A includes a wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound. Correspondingly, a substrate 3300 such as illustrated in Figure 33 A includes a cavity-facing surface, the cavity- facing surface configured to be oriented toward the internal cavity region of a cavity wound. In some embodiments, a substrate 3300 includes at least one cavity-facing surface of the substrate configured to be oriented facing the cavity region of the cavity wound, wherein the cavity-facing surface is positioned opposing the at least one wound-facing surface. For purposes of illustration in Figure 33 A, a single side of the planar surface is shown. In embodiments such as illustrated in Figure 33A, an appurtenance 3330 is a substantially planar, flexible structure. For example, in some embodiments, an appurtenance 3330 includes a substrate 3300 that is a substantially pliable and fluid-permeable structure. For example, an appurtenance 3330 can include a substrate 3300 that is a thin planar structure including a series of apertures 3360 through the depth of the plane. As depicted in Figure 33A and 33 B, in some embodiments a series of apertures 3360 can be positioned at specific locations relative to the surface of the plane. In some embodiments, a series of apertures can be integral to the structure of the substrate 3300. In some embodiments, an appurtenance 3330 can include a substrate 3300 that is a mesh structure. For example, a substrate 3300 of an appurtenance 3330 can include a gauze mesh structure, a woven fabric structure, a foam mesh structure or a plastic mesh structure. A substrate 3300 of an appurtenance 3330 can be fabricated from a number of flexible, pliable materials of sufficient strength to stably affix a series of sensor units 3320. For example, in some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 can be fabricated from gauze or similar bandage materials, silicone, latex, foam, flexible plastic or woven materials. For example, in some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 can be fabricated from woven or non-woven material, film, foam, or alginate composite. In some embodiments, a substrate 3300 of an appurtenance 3330 is fabricated from a composite material, or a combination of materials. A substrate 3300 can be fabricated from a bio-compatible material, so as to minimize inflammation and other secondary effects of the appurtenance 3330. The substrate 3300 is fabricated from materials that are durable under the conditions within a cavity wound 3200. For example, the substrate 3300 should be durable under physiological temperatures and pressures of a cavity wound 3200. For example, the substrate 3300 should be durable in the presence of wound exudate. In some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 includes a substantially flexible, fluid-permeable planar structure of no more than 5 millimeters (mm) in thickness. In some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 includes a substantially flexible, fluid- permeable planar structure of no more than 10 mm in thickness. In some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 100 includes a substantially flexible, fluid-permeable planar structure of no more than 15 mm in thickness. In some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 includes a substantially flexible, fluid-permeable planar structure of no more than 20 mm in thickness. In some embodiments, a substrate 3300 of an appurtenance 3330 to a cavity wound 3200 includes a substantially flexible, fluid-permeable planar structure of no more than 25 mm in thickness.

In some embodiments, the appurtenance includes a porous substrate that is configured to be utilized in association with a cavity wound primary dressing. The substrate is configured as a support for a plurality of sensor units. In some embodiments, the substrate is configured to irreversibly attach directly to an external surface of the wound dressing. In some embodiments, the substrate includes an adhesive on a surface conforming to an external surface of the wound dressing. For example, the surface conforming to an external surface of the wound dressing can include a glue, epoxy, sealant, mucilage, paste or other binder material. For example, the surface conforming to an external surface of the wound dressing can include a series of projections of a size, shape and orientation to affix the surface conforming to an external surface of the wound dressing and the external surface of the wound dressing to each other. In some

embodiments, the surface of the substrate conforming to an external surface of the wound dressing can include an adhesive covered by a removable protective sheet, the sheet configured for detachment and exposure of the adhesive when the appurtenance is attached to the wound dressing. In some embodiments, the surface of the substrate of the appurtenance configured to conform with a surface of the wound dressing can include barbs, hooks, pins, prongs or other extensions configured to adhere or fix into the outer surface of the wound dressing. In some embodiments, a surface of the substrate of the appurtenance configured to conform with an outer surface of a wound dressing can include a mixture or combination of any of the above.

In some embodiments, the substrate includes a flexible material. For example, the substrate can include a pliable plastic, a woven fabric material, foam, soft mesh or other flexible material. In some embodiments, the substrate includes a rigid material. For example, the substrate can include at least one rigid plastic material in a location configured to provide support for a portion of the appurtenance, such an edge region of the appurtenance. For example, the substrate can include at least one rigid plastic material at a location configured to attach a primary or secondary dressing, the rigid plastic configured to provide physical support for the attached dressing. In some embodiments, the substrate includes at least one bio-compatible material. For example, the substrate can include one or more bio-compatible plastic materials, one or more bio-compatible foam materials, one or more bio-compatible fabric materials, or one or more bio-compatible metals.

In some embodiments, an appurtenance 3330 to a cavity wound dressing is substantially sterilized prior to use. For example, the appurtenance 3330 can be treated with one or more chemical disinfectants or UV surface radiation for a period of time sufficient to substantially sterilize the appurtenance 3330 prior to use. For example, the appurtenance 3330 can be treated with one or more antimicrobial gasses, for example ethylene oxide (ETO), prior to use. For example, the appurtenance 3330 can be treated with a chemical sterilizing agent, such as hydrogen peroxide in liquid or vapor form, prior to use. For example, the appurtenance 3330 can be treated with steam as an anti-infective prior to use. In some embodiments, an appurtenance 3330 to a cavity wound dressing includes a sterile wrapper. For example, an appurtenance 3330 to a cavity wound dressing can be stored and/or transported within a sterile wrapper, such as a firm paper wrapper or a plastic film. A sterile wrapper configured for storage and/or transport of an appurtenance 3330 can be treated to minimize contamination, for example coated with one or more antimicrobial agents. In some embodiments, the appurtenance 3330 is substantially sterilized in combination with a wound dressing.

Also as illustrated in Figure 33 A, the appurtenance 3330 includes an attached orientation indicator 3310. In some embodiments, an orientation indicator 3310 can be included to provide positional information regarding the appurtenance 3330. For example, a positional indicator 3310 can be placed at a particular side of the cavity wound 3200 during use. An orientation indicator 3310 can include, for example, a visual graphic. An orientation indicator 3310 can include, for example, a visible electric light, such as an LED, powered by an attached battery. An orientation indicator 3310 can include, for example, a visible chemiluminescent or thermoluminescent indicator. An orientation indicator 3310 can include, for example, an electronically -readable tag or marker for electronic recordation of the appurtenance orientation in the cavity wound. An orientation indicator 3310 can include, for example, an RFID. The appurtenance can also include an electronic identifier, for example a RFID with a specific identifier. An orientation indicator 3310 can, for example, be visible and positioned adjacent to an edge region of an appurtenance 3330 for visible orientation during use or placement of the appurtenance 3330. An orientation indicator 3310 can, for example, be positioned in a central region of an appurtenance 3330 and configured to be detectable non- visually, such as by ultrasound or X-ray scans.

As shown in Figure 33 A, an appurtenance 3330 includes a plurality of sensor units 3320 attached to the substrate 3300, the plurality of sensor units 3320 oriented and positioned on the substrate 3300 relative to the wound surface of the cavity wound. The plurality of sensor units 3320 are configured to detect and report specific conditions at the wound-facing surface of the appurtenance. The term "sensor unit," as used herein, refers to a discrete unit of the appurtenance 3330 that is configured to detect and indicate a condition within the wound cavity. In some embodiments, a sensor unit includes an enclosure, a detector, and an indicator. A sensor unit can be chemically -based. A sensor unit can be mechanically -based. A sensor unit can be electrically-based. A sensor unit can include circuitry. For example, a sensor unit can include a detector of a physical condition, such as physical pressure, temperature, or presence of a specific analyte in a wound cavity. For example, a sensor unit can include a detector of excess moisture. Some embodiments include sensor units configured to detect multiple physical conditions.

Some embodiments include a sensor unit configured to detect both physical pressure and temperature over time. A sensor unit includes an indicator for the presence of the physical condition. For example, a sensor unit including a physical pressure detector can include a color indicator, wherein a stronger or more intense color in a particular visual region indicates that the sensor unit has been subject to physical pressure. For example, a sensor unit including a temperature detector can include a color indicator, wherein a stronger or more intense color in a particular visual region indicates that the sensor unit has been subject to an elevated temperature range. For example, a sensor unit including an analyte detector can include a color indicator, wherein a stronger or more intense color in a particular visual region indicates that the sensor unit has detected the presence of the analyte. See, for example: US Patent Application Publication No. 2007/0269851, "Colorimetric Substrates, Colorimetric Sensors, and Methods of Use," to Sanders et al; and US Patent Application Publication No. 2009/0299161, "Marker of Wound Infection," to Cullen et al, which are each incorporated by reference herein. For example, a sensor unit can include a barrier layer that is broken down in response to proteins present in the wound fluid, releasing a color indicator, such as a dye. See US Patent Application Publication No. 2008/0166397, "Pain-Sensitive Therapeutic Wound Dressing," to Trotter and Culten, which is incorporated herein by reference. Some embodiments include a plurality of sensor units. In embodiments including at least two sensor units, the sensor units can include the same or different indicators.

In some embodiments, the indicator is not a visible indicator. For example, an indicator can include a physical change in at least one material, which can be detected with an external device. For example, an indicator can include chemically reactive materials configured to be released in the presence of an analyte, wherein the released material is detectable with an external device. For example, an indicator can include a material configured to release florescent material in the presence of an analyte. In some embodiments, the physical change in a material in the indicator is a change in conductance or frequency characteristics in the presence of an electromagnetic signal. For example, the indicator can include a RFID antenna with a frequency characteristic that is altered in the presence of a fluid, such as blood.

A variety of sensor units including different detectors can be utilized in different embodiments of the appurtenances, depending on factors such as the intended use of the appurtenance, size, weight, cost, bio-compatibility, safety and ease of disposal. Detectors can be of a variety of types depending on the embodiment. A sensor unit can include at least one detector responsive to changes in capacitance, or a measure of the ability of a configuration of materials to store electric charge. A general review of biosensors that detect changes in the dielectric properties of an electrode surface can be found in Berggren et al, "Capacitive Biosensors," Electroanalysis vol. 13, no. 3, 173-180, (2001), which is incorporated herein by reference. For example, one or more detectors can include a micromechanical biosensor with a fixed- fixed beam attached to an interdigitated capacitor {see, for example, Lim et al., "A Micromechanical Biosensor with Interdigitated Capacitor Readout," Proceedings of the 2011 IEEE/ICME International Conference on Complex Medical Engineering, May 22-25, Harbin, China, which is incorporated herein by reference). Sensor units can also include detectors utilizing nanowire nanosensors, for example as described in Cui et al, "Nanowire Nanosensors for Highly Sensitive and Selective Detection of Biological and Chemical Species," Science, vol. 293, 1289-1292 (2001), which is incorporated herein by reference. Sensor units can include detectors utilizing antibodies secured to a graphene substrate. See Tehrani et al., "Detection of

Monoclonal Antibodies using Chemically Modified Graphite Substances," IEEE Sensors 2010 Conference Proceedings, 428-431, (2010), which is incorporated herein by reference. In some embodiments, sensors include aptamer-modified graphene field-effect transistors, see Ohno et al., "Graphene Field-Effect Transistors for Label-Free Biological Sensors," IEEE Sensors 2010 Conference Proceedings, 903-906, (2010), which is incorporated herein by reference. A sensor unit in an appurtenance can interact with a sensor present in a wound dressing, for example as described in US Patent No. 6,283,938 to McConnell, titled "Medicating Bandage and Controllable Permeable Membrane," which is incorporated herein by reference. A sensor unit can include a field effect transistor (FET), such as described in US Patent No. 7,507,675 to Zuilhof et al, titled "Device Manufacturing Method and Device," which is incorporated herein by reference. A sensor unit can include a nano-cantilever device, such as described in US Patent No. 7,612,424 to Espinosa and Ke, titled "Nanoelectromechanical Bistable Cantilever Device," which is incorporated herein by reference. An appurtenance can include sensor units including test electrodes configured as an array. See US Patent No. 7,945,302 "Wound Mapping System," to McAdams, which is incorporated by reference.

Sensor units such as those described herein can be configured to detect fluids. Some embodiments include a sensor unit configured to detect an excess level of fluid at the sensor unit. Sensor units such as those described herein can be configured to detect one or more components of a fluid. Sensor units such as those described herein can be configured to detect one or more analytes within a fluid. As used herein, fluid includes both gasses and liquids individually or as mixtures. In some embodiments, sensor units described herein can detect fluids, whether in gaseous state or liquid state. If the fluid is a liquid, it can be drawn into an appurtenance, such as to a position adjacent to a sensor unit, through capillary action. If the fluid is a gas, it can be drawn into the appurtenance through gravity (i.e. where the appurtenance is oriented on the top of a wound surface within a cavity wound). In some embodiments, the appurtenance includes a micropump positioned to move fluids into an appurtenance substrate to a position adjacent to a sensor unit. In some embodiments, the sensor unit includes a sealed chamber that is under vacuum and connected to an aperture in the enclosure of the sensor unit. When the seal on the chamber is broken, fluid moves into the sensor unit in response to the low (or negative) air pressure in the tube. Some embodiments include an internal hydrophobic region positioned over an aperture in the sensor unit, wherein both a sufficient quantity and pressure of fluid adjacent to the sensor unit are required to overcome the hydrophobicity so that the fluid moves through the aperture and into the sensor unit for detection.

The appurtenance can include an energy storage unit. For example, an

appurtenance can include an energy storage unit, such as a battery, operably attached to a processor and one or more sensor units. In some embodiments, the appurtenance does not store energy. The appurtenance can include an energy harvesting unit, such as a unit configured to obtain energy from electromagnetic waves. See, for example, US Patent No. 7,479,886 to Burr titled "Antenna Capacitance for Energy Storage" and Sample et al., "Photovoltaic Enhanced UHF RFID Tag Antennas for Dual Purpose Energy Harvesting," 2011 IEEE International Conference on RFID, 146- 153 (2011), which are each incorporated herein by reference. In some embodiments, a plurality of sensor units each include at least one energy harvesting unit, for example RFID units. In some

embodiments, the appurtenance includes an indicator operably attached to a processor, the indicator positioned on an edge of the appurtenance adjacent to an outer surface of the wound when the appurtenance is positioned for use with the wound dressing. For example, the indicator can include a least one of: a visual indicator, a vibratory indicator, or an auditory indicator. See, for example, US Patent Application No. 2009/0167495 to Smith, titled "Radio Frequency Identification Tags Adapted for Localization and State Indication," which is incorporated herein by reference.

In some embodiments, an appurtenance to a cavity wound dressing includes a transmitter unit. In some embodiments, an appurtenance includes a transmitter unit within at least one sensor unit. For example, in some embodiments, a sensor unit includes a transmitter unit, including an antenna. In some embodiments, a transmitter unit is part of an indicator within the sensor unit. In some embodiments, an appurtenance includes a transmitter unit operably connected to one or more sensor units. For example, an appurtenance to a cavity wound dressing can include a single transmitter unit connected with a wire to one or more sensor units. In some embodiments, a sensor unit is configured for a transmitter unit to operate as an indicator when a condition within a wound cavity is detected. For example, a sensor unit can include a RFID antenna attached to a temperature sensor including a bimetallic element that flexes at varying temperatures between 32 degrees Centigrade and 45 degrees Centigrade. The flex position of the bimetallic element is positioned adjacent to the RFID antenna, so that greater flex decreases the contact of the bimetallic element with the RFID antenna. In conditions wherein the bimetallic element of the temperature sensor is significantly flexed (e.g. approximately 45 degrees

Centigrade), the bimetallic element has less contact with the RFID antenna relative to conditions wherein the bimetallic element of the temperature sensor is not significantly flexed (e.g. approximately 32 degrees Centigrade). The change in contact between the bimetallic element and the RFID antenna changes the response of the antenna, thereby varying the response of the transmitter unit depending on the temperature.

A "transmitter unit," as used herein, can be one or more of a variety of units that are configured to send and/or receive signals, such as signals carried as electromagnetic waves. In embodiments where the appurtenance includes a substrate, the transmission unit can be attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal. A transmitter unit generally includes at least one antenna and associated circuitry. A transmitter unit can include a transmitter and a receiver. Alternatively, the receiver can be a separate unit, with its own antenna and associated circuitry. A transmitter unit can include volatile or non-volatile memory. A transmitter unit can include a processor. A transmitter unit can be operably connected to an energy source, such as a battery. In some embodiments of an appurtenance, it is desirable to include a self-compensating antenna, such as described in US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates having Differing Dielectric Constant Values," which is incorporated herein by reference. A transmitter unit can be operably connected to a processor. A transmitter unit can be operably connected to a sensor unit. A transmitter unit can be configured to transmit a signal in response to a received interrogation signal. A transmitter unit can include an energy harvesting unit, such as a unit configured to obtain energy from electromagnetic waves. A transmitter unit can include a transponder utilizing electromagnetic waves, for example as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and

Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference. A transmitter unit can include an oscillator and encoder configured to generate a programmable pulse position-modulated signal in the radio frequency range. See, for example, US Patent No. 4,384,288 to Walton, titled "Portable Radio Frequency Emitting Identifier," which is incorporated herein by reference. A transmitter unit can include a radio frequency identification device (RFID). A transmitter unit can be configured to be a transmitter of signals in the UHF range. A transmitter unit including an RFID device can be configured to transmit signals in the UHF standard range utilized in a global region, as illustrated in the "Worldwide RFID UHF Map" by Intelleflex

Corporation (©2009), which is incorporated herein by reference. A transmitter unit can include a radio frequency identification device (RFID), which can be a passive RFID device, a semi-passive RFID device, or an active RFID device, depending on the embodiment. See, for example, Chawla and Ha, "An Overview of Passive RFID," IEEE Applications and Practice, 11-17 (September 2007), which is incorporated herein by reference. A transmitter unit can include a battery-assisted passive RFID device, such as sold by Alien Technology®, Morgan Hill, CA, such as described in the brochure from Alien Technology® titled "Battery Assisted Passive Tags" and incorporated herein by reference. A transmitter unit can include an optical transmitter unit. A transmitter unit can be configured to transmit at approximately 13.56 megahertz (MHz), or within the ISO 14443 standard parameters. See Patauner et al., "High Speed RFID/NFC at the Frequency of 13.56 MHz," presented at the First International EURASIP Workshop on RFID

Technology, pages 1-4, 24-25 September 2007, Vienna Austria, which is incorporated herein by reference. A transmitter unit can include at least two antennas. A transmitter unit can include a self-compensating antenna system. An antenna can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference. A transmitter unit can include a hybrid backscatter system configured to function in an RFID, IEEE 802.1 lx standard and Bluetooth system. See, for example, US Patent No. 7,215 ,976 to Brideglall, titled "RFID Device, System and Method of Operation Including a Hybrid backscatter-based RFID Protocol Compatible with RFID, Bluetooth and/or IEEE 802.1 lx Infrastructure," which is incorporated herein by reference. A transmitter unit can be configured to transmit at approximately 131 kilohertz (KHz), for example as part of a RuBee™ (IEEE standard 1902.1) system (sold, for example, by Visible Assets™, Inc.). See for example: the description of RuBee™ systems from the Visible Assets™ webpage; Stevens et al, "RuBee (IEEE 1902.1) - The Physics Behind, Real-Time, High Security Wireless Asset Visibility Networks in Harsh Environments," a white paper from Visible Assets™; and in US Patent Application No. 2007/0171076 to Stevens and Waterhouse, titled "Low-frequency Radio Tag Encapsulating System," each of which are incorporated herein by reference. A transmitter unit can include a near field communication (NFC) device. A transmitter unit can include a Wireless Identification and Sensing Platform (WISP) device, manufactured by Intel Corporation, such as described in the "WISP: Wireless Identification and Sensing Platform" webpage (downloaded on October 28, 2011) incorporated herein by reference. A transmitter unit can be operably coupled to a sensor, such as a sensor that detects changes in capacitance {see, e.g. Sample et al, "A

Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which is incorporated herein by reference). A transmitter unit can be operably coupled to a sensor, such as described in: Ruhanen et al, "Sensor-enabled RFID Tag and Handbook," from Building Radio Frequency Identification for the Global Environment (2008); Sample et al, "Design of an RFID-Based Battery-Free

Programmable Sensing Platform," IEEE Transactions on Instrumentation and

In some embodiments, the transmitter unit can include an optical transmitter. For example, an optical transmitter unit can include one or more white light emitting diodes (LEDs). For example, an optical transmitter unit can include an infrared laser. For example, an optical transmitter unit can include a visible laser. In some embodiments, optical transmitter units can be desirable to minimize interference from nearby electrical equipment, such as medical equipment. See: Kavehrad, "Sustainable Energy-Efficient Wireless Applications Using Light," IEEE Communications Magazine, vol. 48, no. 12, pages 66-73, (2010); and Fadlullah and Kavehrad, "Indoor High-Bandwidth Optical

Wireless Links for Sensor Networks" Journal of Lightwave Technology, vol. 28, no. 21, pages 3086-3094 (2010), which are incorporated herein by reference.

A sensor unit can include an indicator that is configured to actuate a switch in response to a stimulus from a detector. The sensor unit can be configured to cause a change in the state of the switch in response to a stimulus, such as the presence of an analyte. A "selectively actuatable switch," as used herein, refers to a switch of sufficient structure to allow or disallow a transmission unit to transmit a signal in response to a sensor unit. A selectively actuatable switch includes a switch that can be turned between settings {i.e. "on" and "off) in response to a stimulus. A selectively actuatable switch can, for example, be coupled to a transmission unit that includes an RFID device. See, for example, US Patent No. 7,411,505 titled "Switch Status and RFID Tag," which is incorporated herein by reference. A selectively actuatable switch can be a binary switch, or a switch with substantially two settings {i.e. "on" and "off). A selectively actuatable switch can be configured to be irreversible, or to irreversibly go from one state to a second state. A selectively actuatable switch can be configured to be responsive to a change in capacitance.

Some embodiments include sensor units with detectors that are configured to be responsive to a change in the pH of fluid arising from the wound surface, or wound exudate. For example, pH changes can indicate potential infection in the cavity wound, or in a region of the cavity wound. For example, pH changes in wound exudate can indicate that a section of the wound cavity has an increased level of necrotic tissue, and a caregiver may wish to consider debridement. Detectors of pH can be, for example, iridium oxide based pH detectors. See, for example: the "flexible, iridium oxide pH sensor for wound dressing material" project from the University of Texas at Arlington, (information sheet identified as UTA reference number 08-21); and US Patent Application Publication No. 2011/0140703 to Chiao et al., which are each herein incorporated by reference.

Some embodiments include sensor units with detectors that recognize analytes that are specific proteins. Some embodiments include sensor units with detectors that recognize specific analytes present in wound exudate. For example, in some embodiments detectors recognize bacterial proteins indicative of chronic, or long-term, non-healing cavity wounds. See Dowd et al, "Survey of Bacterial Diversity in Chronic Wounds Using Pyrosequencing, DGGE, and Full Ribosome Shotgun Sequencing," BMC Microbiology 8:43 (2008), which is incorporated by reference. These bacterial proteins can be present on the wound surface, or in the wound exudate from a cavity wound. Some embodiments include detectors of ATP levels in fluid originating from the surface of a cavity wound. See International Publication No. WO 00/08203, "Method of Monitoring Bacterial Contamination in a Wound," to Walker, which is incorporated by reference herein. Some embodiments include detectors of oxygen in fluid within the cavity wound and indicators including luminescent markers. See Grist et al, "Optical Oxygen Sensors for Applications in Microfluidic Cell Culture," Sensors 10:9286-9316 (2010), which is incorporated by reference. Low oxygen levels in a cavity wound can indicate to a caregiver, for example: a lack of vascular function in the periwound tissue; a bacterial infection; or excess necrotic tissue. In some embodiments, sensor units include detectors with an antibody that detects Cortisol, and an indicator including a visualization of antibody binding. See US Patent No. 5,912,114, "Wound Diagnosis by Quantitating Cortisol in Wound Fluids," to Hutchinson et al, which is incorporated by reference. In some embodiments, sensor units include detectors that respond to markers of inflammation, such as described in US Patent No. 7,794,925, "Diagnosis of Clinical Infection of a Wound" to Cullen, and International Publication No. WO 03/040406, "Wound Monitoring," to Cullen, which are each incorporated by reference. In some embodiments, sensor units include detectors that respond to markers of infection including high molecular weight phospholipase A₂. See US Patent Application Publication No. 2007/0231380, "Diagnosis and Prognosis of Wound Infection by Measurement of Phospholipase A2 in Wound Fluid," to Shah et al, which is incorporated by reference. In some embodiments, the absence of a protein in wound fluid or exudate can be clinically relevant information. See US Patent Application Publications Nos. 2010/0166694 and 2012/0010099, each "Diagnostic Markers of Wound Infection," to Stephens et al, which are each incorporated by reference.

Figure 33 A depicts an appurtenance 3330 including a substrate with a plurality of affixed sensor units 3320A, 3320B, and 3320C. The plurality of sensors 3320A, 3320 B and 3320C are collectively referred to as 'sensor units 3320' with reference to the Figures herein. Such plurality of sensor units 3320 can include sensors of the same or distinct types. In the embodiment illustrated, the appurtenance 3330 includes a plurality of affixed sensor units of three distinct types 3320A, 3320B, 3320C. The sensor units of different types are configured to indicate the presence of different conditions or analytes within a cavity 120 of a cavity wound 100. For purposes of illustration, the sensor units 3320A, 3320B, 3320C are depicted in Figure 33A as different shapes, although in actual embodiments there need not be any overt or visual difference between sensor units of different types. Although the embodiment illustrated includes sensor units of three distinct types, 3320A, 3320B, 3320C, some embodiments include a single sensor type, two sensor types, or more than three sensor types. As shown in Figure 33 A, an appurtenance 3330 including a substrate with a plurality of affixed sensor units can include a plurality of sensor units of at least three distinct types 3320A, 3320B, 3320C oriented as a pattern relative to the wound surface. In some embodiments, a plurality of sensor units of at least two distinct types are oriented as a pattern relative to the wound surface. For example, at least one sensor unit, e.g., 3320A including a detector of physical pressure can be affixed to the substrate 3300 at a location corresponding to a region of the wound surface adjacent to a bone. A position of a cavity wound 3200 surface adjacent to a bone can be particularly prone to further injury due to physical pressure, and monitoring of physical pressure at such a location with the appurtenance 3330 may be desirable in some medical situations. An appurtenance 3330 including a substrate with a plurality of affixed sensor units can include a plurality of sensor units including at least one sensor unit 3320B configured to detect both physical pressure and temperature over time.

An appurtenance 3330 including a substrate with a plurality of affixed sensor units can include a plurality of sensor units 3320 which in the aggregate have been selected and positioned on the appurtenance substrate with a size, shape, mass and arrangement to minimize physical pressure at the wound surface from the appurtenance. For example, substrate with a plurality of affixed sensor units can include a plurality of sensor units of a size, shape, mass and arrangement so that the appurtenance is predicted to press with a force of less than 32 mm Hg at the wound surface during use with the cavity wound. For example, substrate with a plurality of affixed sensor units can include a plurality of sensor units of a size, shape, mass and arrangement so that the appurtenance is predicted to press with a force of less than 20 mm Hg at the wound surface during use with the cavity wound. For example, substrate with a plurality of affixed sensor units can include a plurality of sensor units of a size, shape, mass and arrangement so that the appurtenance is predicted to press with a force of less than 12 mm Hg at the wound surface during use with the cavity wound. In some embodiments, a smaller and thinner type of sensor unit is positioned on the substrate adjacent to the center of the appurtenance, assuming that the center of the appurtenance will be positioned adjacent to the center of the wound, a particularly sensitive region, during use of the appurtenance. In some embodiments, a relatively larger and thicker type of sensor unit is positioned adjacent to the edge of the appurtenance, assuming that the edge will be positioned outside of the wound itself during use of the appurtenance. The plurality of affixed sensor units can be fabricated of substantially thin and lightweight materials. For example, affixed sensor units can be fabricated to be less than 5 mm in thickness, less than 10 mm in thickness, less than 15 mm in thickness, less than 20 mm in thickness, or less than 25 mm in thickness. The plurality of affixed sensor units can be fabricated with a flexible, lightweight cover to minimize physical pressure from the sensor units within the cavity wound 100 during use. For example, one or more sensor units affixed to the substrate 3300 can include a foam cover. For example, one or more sensor units affixed to the substrate 3300 can include a flexible plastic cover around an edge region of the sensor units.

In some embodiments, a substrate 3300 includes a plurality of unidirectional fluid flow structures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound-facing surface to one or more of the plurality of sensor units 3320 attached to the substrate 3300. See, for example, US Patent No. 6,420,622 to Johnston et al., "Medical Article Having Fluid Control Film," which is incorporated herein by reference. For example, the substrate 200 can include a plurality of channels or grooves in the surface configured to allow fluid flow from the wound-facing surface to one or more of the plurality of sensor units 3320 attached to the substrate 3300.

An appurtenance can be fabricated from a variety of materials, as appropriate to an embodiment. An appurtenance can be fabricated, for example, substantially from a plastic material. For example, a structural portion, such as a substrate, can be fabricated from a plastic material. An appurtenance can be fabricated, for example, from one or more acrylics, polyesters, silicones, polyurethanes and halogenated plastics. An appurtenance can be fabricated from one or more bio-compatible materials, for example bio-compatible plastics, foams, resins, epoxies and metals. An appurtenance can be fabricated from one or more composite materials, such as plastic with an overlay of epoxy or plastic with an overlay of one or more metals. An appurtenance including a transmission unit can include, for example, one or more metal components, for example as circuitry or as one or more antennas. An appurtenance including a transmission unit can include, for example, stainless steel, copper or zinc alloy. An appurtenance can be fabricated from one or more ceramic materials, such as within a transmission unit. Generally, it is envisioned that materials with low mass will be suitable for a variety of appurtenance embodiments, so as to reduce weight and associated physical stress on a wound dressing. Similarly, it is envisioned that materials with sufficient strength and toughness to be fabricated into small and thin components will be desirable for fabrication of appurtenance embodiments. As the appurtenances are configured for use with wound dressings and disposed of with the wound dressings, materials that do not require special handling or disposal are preferable in most embodiments.

Appurtenances such as those described herein can be configured to be used in conjunction with cavity wound dressings wherein the patient is being directly monitored using other devices, for example as described in US Patent No. 7,030,764 to Smith and Cooper, titled "Apparatus and Method for Reducing the Risk of Decubitus Ulcers;" US Patent No. 7,297,112 to Zhou et al, titled "Embedded Bio-Sensor System;" US Patent Nos. 7,372,780, 8,014,234 and 7,813,226 to Braunberger, titled "Timing System and Device and Method for Making the Same;" US Patent No. 7,666,151 to Sullivan et al, titled "Devices and Methods for Passive Patient Monitoring;" US Patent No. 7,703,334 to Cochran, titled "Bandage Type Sensor Arrangement and Carrier Assembly Therefore, and Method of Manufacture;" and International Patent Publication No. WO 2005/009328 to Nikolic, titled "ABT- Anti-Bedsore Timer," which are each incorporated herein by reference. Appurtenances such as those described herein can also be used in conjunction with a system to monitor assets within a health care facility, for example as described in US Patent Application No. 2007/0247316 to Wildman et al, titled "Article Locating and Tracking Apparatus and Method," which is incorporated herein by reference. Figure 33B illustrates an appurtenance 3330 to a cavity wound dressing in use. Figure 33B shows a cross-section view of a substantially planar, flexible appurtenance substrate 3300, such as shown in an external view in Figure 33A, in situ within a cavity wound 3200. As shown in Figure 33B, the cavity wound 3200 creates a cavity 3220 within a body part 3210, such as a leg {e.g. as illustrated in Figure 32A). The cavity wound 3200 has a wound surface 3230 and a surface region 140 of the periwound region. The substrate 3300 has a thin, flexible structure that substantially conforms to the wound surface 3230 of the cavity wound 3200. The substrate 3300 illustrated in Figure 33B has a surface size larger than the wound surface 3230 of the cavity wound 3200, and therefore part of the substrate 3300 covers the surface region 3240 of the periwound region. The substrate 3300 includes a wound-facing surface 3350 configured to face the wound surface 3230. For example, the wound-facing surface 3350 can be configured to be substantially smooth in order to minimize the potential for regions of localized pressure at the wound surface 3230 when the appurtenance is in use. For example, the wound-facing surface 3350 can include one or more apertures 3260 in the wound-facing surface 3350, the apertures 3260 configured to allow fluid flow from the wound surface 3230 to one or more attached sensor units 3220. The substrate 3300 includes a cavity-facing surface 3340. The cavity-facing surface 3340 can include, for example, one or more attachment sites for the attachment of a primary wound dressing. The cavity-facing surface 3340 can include, for example, one or more attached sensor units 3320. The cavity-facing surface 3340 can include, for example, one or more orientation indicators 3310 for placement of the appurtenance within the cavity 3220 and orientation of the appurtenance after removal from the cavity 3220.

Some embodiments include an appurtenance to a cavity wound dressing, wherein the appurtenance includes: a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when immersed in fluid or under physiological physical pressure and temperature within a cavity wound; and the plurality of sensor units in the aggregate of a size and mass to allow for medical use with the porous dressing material at the cavity wound.

For example, the plurality of sensor units can include at least two types of sensor units {e.g. sensor units with detectors configured to detect two or more distinct analytes, or sensor units configured to detect both specific analytes and specific conditions within the cavity). Some embodiments include a plurality of sensor units including at least one sensor unit configured to detect physical pressure and at least one sensor unit configured to detect temperature. For example, a first sensor unit can detect physical pressure, and a second sensor unit can detect temperature. The first sensor unit and the second sensor unit can be positioned adjacent to each other relative to the surface of the appurtenance. Some embodiments include a plurality of sensor units including at least one sensor unit configured to detect physical pressure and at least one sensor unit configured to detect temperature, as well as at least one sensor unit configured to detect elapsed time. For example, a first sensor unit can detect physical pressure and a second sensor unit can detect temperature and a third sensor unit can record an elapsed time value. For example, a first sensor unit can detect physical pressure and a second sensor unit can detect temperature and a third sensor unit can detect an elapsed time value, while an external device receiving the record from the first, second and third sensors can calculate the pressure and temperature over time from the data obtained from the first, second and third sensors. For example, the external device receiving the record from the first, second and third sensors can indicate a composite score of temperature and pressure over elapsed time based on data received from the first, second and third sensors. For example, a sensor unit can detect physical pressure and indicate if the detected values have exceeded a pre-set threshold value. For example, a sensor unit can detect temperature and indicate if the detected values have exceeded a pre-set threshold value. For example, a sensor unit can detect elapsed time and indicate if the elapsed time value has exceeded a pre-set threshold value.

Some embodiments include a plurality of sensor units including at least one sensor unit configured to detect an analyte in wound exudate. For example, a sensor unit can include a detector configured to detect an analyte such as a blood protein, a bacterial protein, a viral protein, or a biomarker. Some embodiments include a plurality of sensor units of a size, shape, mass and arrangement in the aggregate to minimize physical pressure at the wound surface during medical use with a porous dressing material. For example, the mass of the sensor units in the aggregate can be less than a predetermined maximum mass. For example, a sensor unit can include soft and flexible outer coatings. For example, a sensor unit can be configured with substantially low aspects for the embodiment. The sensor units can be arranged on different sizes and shapes of appurtenance substrates to minimize physical pressure on the wound surface during use. Some embodiments include a plurality of sensor units including at least one antenna operably attached to at least one sensor unit. Some embodiments include a plurality of sensor units including at least one chemical or biological-based sensor unit, as described herein. Some embodiments include a plurality of sensor units including at least one positional indicator. Some embodiments include a plurality of sensor units including at least one temperature sensor unit. Some embodiments include a plurality of sensor units including at least one pressure sensor unit. Some embodiments include a plurality of sensor units including at least one fluid-activated sensor unit. Some embodiments include a plurality of sensor units including at least one sensor unit including an optically resolvable detection indicator. Some embodiments include a plurality of sensor units including at least one sensor unit including a detection indicator operably attached to a RFID antenna. Some embodiments include a plurality of sensor units including a plurality of sensor unit types, wherein all of the plurality of sensor unit types are functional under expected environmental conditions, such as temperature, moisture, and physical pressure, within a cavity of the cavity wound. In some embodiments, one or more sensor unit is operably connected to a transmission unit. In some embodiments, one or more sensor unit is externally-readable. For example, a sensor unit can be externally-readable by an external device. For example, a sensor unit can include a detector configured to transmit a specific wavelength of light in the presence of an analyte and in response to UV excitation by an external source. An external device can be utilized to scan a previously used appurtenance with UV and then to detect the transmitted specific wavelength from the sensor unit.

In some embodiments, an appurtenance includes at least one orientation indicator including an attachment region configured to affix to a porous wound dressing material. For example, the orientation indicator can include a detachable cover over an adhesive backing on one surface, and a visible pattern on another surface. In some embodiments, an appurtenance includes a porous wound dressing material suitable for attachment of the plurality of sensor units, the porous wound dressing material being flexible. For example, a porous wound dressing material can be fabricated from porous medical-grade silicone. For example, a porous wound dressing material can be fabricated from a foam material.

Figure 34 shows an appurtenance 3330 to a cavity wound dressing 3400 in use. The view shown in Figure 34 is a cross-section view of a cavity wound 3200 forming a cavity 3220 in a body part 3210, similar to the view shown in Figure 33B. The interior of the cavity 3220 of the cavity wound 3200 has a wound surface 3230. Figure 34 illustrates an appurtenance with a substrate 3300 that is a flexible, porous sheet structure with a wound-facing surface 3350 positioned adjacent to the wound surface 3230. The appurtenance with a substrate 3300 includes a cavity-facing surface 3340 positioned adjacent to the interior region of the cavity 3220. The wound 3200 also includes a wound dressing 3400 positioned within the cavity 3220 and adjacent to the cavity-facing surface 3340 of the substrate 3300 of the appurtenance. The wound dressing 3400 can include, for example, gauze dampened with sterile saline, positioned to reduce dryness at the wound surface 3230 and to retain the cavity 3220 as an open, uncompressed structure. In a configuration such as shown in Figure 34, saline or other fluid from the wound dressing 3400 can pass through the porous substrate 3300 of the appurtenance in order to retain a moist environment at the wound surface 3230. Wound exudate, including blood and other fluids, can also pass to the wound-facing surface 3350 of the porous substrate 3300 of the appurtenance, and to the sensor units embedded within the substrate 3300.

Figure 35 A illustrates aspects of an appurtenance 3330. The appurtenance 3330 shown in Figure 35 A is a structure configured to approximate the interior size and shape of a cavity in a cavity wound. The appurtenance 3330 shown in Figure 35 A includes a three dimensional structure with at least one wound-facing surface, the at least one wound- facing surface of a size and shape to reversibly mate with the wound surface of the cavity wound. The appurtenance 3330 is fabricated with a substantially pliable and fluid- permeable structure 3510, 3500, 3520. The appurtenance depicted in Figure 35 A includes a substrate with one or more walls 3500 configured to approximate the size and shape of a cavity in a cavity wound. The substrate also includes a distal region 3520 connected to the walls 3500. The substrate is substantially pliable and porous, while retaining enough rigidity to maintain the approximate three-dimensional structure of the substrate within the cavity. The substrate is sufficiently flexible to bend or conform as needed during normal movement of an individual while it is in use, while not creating a pressure greater than 32 mm Hg against the wound surface.

The appurtenance 3330 shown in Figure 35 A includes an edge region 3510, the edge region including a surface 3550 positioned to be adjacent with the surface region of the periwound region when the appurtenance 3330 is in use. The edge region 3510 also includes a surface 3560 positioned to be distal to the surface region of the periwound region when the appurtenance 3330 is in use. The surface 3560 of the edge region 3510 can, for example, be visible to a caregiver when the appurtenance 3330 is in use. In the embodiment shown in Figure 35 A, the surface 3560 of the edge region 3510 includes an attached orientation indicator 3310. The orientation indicator 3310 can include, for example, a visible marking that can assist a caregiver with orienting the appurtenance within a cavity wound during wound care. The surface 3560 of the edge region 3510 shown in Figure 35A also includes a temperature sensor unit 3540. The temperature sensor unit 3540 can be configured to detect the temperature at or proximate to a surface region of the periwound region when the appurtenance 3330 is in use. See US Patent No. 6,963,772, and US Patent Application Publication No. 2006/0047218 "User-Retainable Temperature and Impedance Monitoring Methods and Devices," each to Bloom, which are each incorporated by reference. The temperature sensor unit 3540 can be configured to detect and record the temperature at or proximate to a surface region of the periwound region over time, for example for use in comparison with a temperature record from a sensor unit attached to the substrate 3500, 3520 positioned within a wound cavity.

Figure 35B illustrates a view of the appurtenance of Figure 35 A in situ within a cavity wound 3200. The appurtenance is positioned within the cavity 3220 of the cavity wound 3200 so that the surface 3550 of the edge region 3510 is adjacent to the surface region 3240 of the periwound region. The walls 3500 of the appurtenance are oriented substantially parallel to the sides of the wound cavity 3220. The distal region 3520 of the appurtenance is oriented adjacent to the distal region of the wound cavity 3220. The wound-facing surface 3350 of the appurtenance is oriented adjacent to the wound surface 3230. In the embodiment illustrated in Figure 35B, there is a space or gap between the wound-facing surface 3350 of the appurtenance and the wound surface 3230. In some embodiments, a therapeutic agent can be utilized to fill the gap between the wound-facing surface 3350 of the appurtenance and the wound surface 3230. The gap can be filled, for example, with a medicament, such as an alginate-based compound. The gap can be filled, for example, with an antibacterial agent in a gel or foam base. In some embodiments, the wound-facing surface 3350 of the appurtenance is configured to reversibly mate with the wound surface 3230 with a minimal gap. The appurtenance illustrated in Figure 35B includes a substrate 3500, 3510, 3520 fabricated from a thin material so that the cavity- facing surface 3340 of the substrate faces an internal cavity 3220.

Figure 36 illustrates a cross-section view, showing aspects of an appurtenance, such as shown in Figures 35A and 35B, in use in situ with a wound dressing 3400 and a secondary wound dressing 3600 on a cavity wound 3200. The appurtenance is positioned within the cavity 3220 of the cavity wound 3200 in a similar fashion to the view shown in Figure 35B. The cavity-facing surface 240 of the substrate creates an internal region of the substrate 3500, 3510, 3520 within the cavity 3220. The internal region of the appurtenance holds a wound dressing 3400. The wound dressing 3400 is a substantially planar structure, which has been compressed into the cavity 3220 space of the wound 3200. For example, the wound dressing 3400 can include a saline-saturated gauze material folded to pack into the cavity 3220. The porous substrate 3500, 3520 allows fluid from the wound dressing 3400 to flow to the wound surface 3230 as well as fluid from the wound surface 3230 to flow to the wound dressing 3400. A secondary dressing 3600 is positioned over the appurtenance and the wound dressing 3400. For example, the secondary dressing 3600 can include a thin plastic film with adhesive on the surface facing the wound 3200. The adhesive can secure the secondary dressing 3600 to the surface region 3240 of the periwound region as well as to the edge region 3510 of the

appurtenance, thereby retaining the appurtenance, the wound dressing 3400 and the secondary dressing 3600 in place during use.

Figure 37 illustrates an appurtenance 3700 to a wound dressing for a cavity wound. The appurtenance 3700 illustrated is a substantially planar, elongated structure including a substrate 3710 with an array of attached sensor units 3320. The sensor units 3320 depicted are of three types 3320A, 3320B, 3320C, which are configured to detect at least three types of analytes and/or conditions within a wound cavity. Although three types of sensor units 3320A, 3320B, 3320C are depicted in Figure 37, some embodiments include a single type of sensor unit 3320, two types of sensor units 3320, or more than three types of sensor units 3320. The sensor units 3320A, 3320B, 3320C depicted in Figure 37 are shown as different shapes (triangle, star, and circle respectively), for purposes of illustration, however sensor units 3320A, 3320B, 3320C configured to detect different analytes can have the same external appearance. The appurtenance 3700 illustrated in Figure 37 has the sensor units 3320 attached to the substrate in an array, which is oriented as linear rows of each type of sensor unit 3320A, 3320B, 3320C along the length of the appurtenance 3700. A substrate 3710 in an embodiment such as that illustrated is fabricated from a flexible, porous material that is stable and durable in physiological conditions within a wound cavity, such as temperature and pressure. A substrate 3710 in an embodiment such as that illustrated is stable and durable in the presence of cavity wound fluid and exudate. The substrate is porous to fluids within the wound cavity, for example, sterile saline or similar medicaments used with a primary dressing, or blood or other wound-based fluids and exudate. For example, a substrate 3710 can be fabricated from a plastic mesh, gauze, or foam material. For example, a substrate 3710 can be fabricated from medical-grade woven mesh, gauze or fabric. The substrate 3710 can include layers of different materials. In some embodiments, the sensor units 3320 are embedded within the substrate 3710, such as between layers of the substrate 3710 structure. The sensor units 3320 attached to the substrate 3710 are oriented and positioned to detect analytes and conditions in a wound cavity in the region adjacent to the appurtenance 3700. The appurtenance 3700 is configured for use within a wound cavity, and is, therefore, soft, pliable, durable and operational under physiological temperatures, conditions, and physical pressures. The appurtenance 3700 is configured for use within a wound cavity, and is, therefore, of a mass and configuration to not place physical pressure or shear force on a wound surface within a cavity wound during use. For example, the total mass of the appurtenance 3700, including the substrate 3710 and the sensor units

3320, should be minimized in a given embodiment to reduce the total physical pressure on the wound surface. For example, each of the individual sensor units 3320 should be configured with minimal mass and aspect to not create localized pressure or physical shear force against a region of the wound surface. The appurtenance 3700 is configured to be used when dry, damp or wet. For example, the appurtenance may be damp during use when the wound dressing is an alginate material coating at least one surface of the substrate 3710. For example, the appurtenance may be damp during use when the wound dressing is a saline-soaked gauze material affixed to the substrate 3710. For example, the appurtenance may be dry during use and then become wet with wound exudate over time during use in the cavity wound.

In some embodiments, an appurtenance substrate can be fabricated with one or more regions configured for the attachment of different modules. In some embodiments, an appurtenance includes modules that are configured for removal and replacement.

During fabrication, a basic appurtenance substrate structure can be utilized and different specific modules added as desired in a particular embodiment. For example, an appurtenance substrate can be fabricated with at least one region configured to attach a sensor unit. For example, a region configured to attach a sensor unit can include a region with a surface conforming to an outer surface of the sensor unit. For example, a region configured to attach a sensor unit can include a conduit configured to align with a hollow interior region of the sensor unit. For example, a region configured to attach a sensor unit can include a conduit configured to align with a detection region of a sensor unit. The region of the appurtenance substrate configured to attach a sensor unit can be configured for attachment of different types of sensor units, depending on the embodiment. For example, the region of the appurtenance substrate configured to attach a sensor unit can be configured for attachment of sensor units of different dimensions or different materials as desired in the construction of a particular embodiment. In some embodiments, an appurtenance substrate can have multiple regions configured for attachment of multiple sensor units of different types. In some embodiments, an appurtenance substrate can have one or more removable antenna modules. For example, an appurtenance substrate can have one or more removable power source modules, such as batteries. In some embodiments, a module can include a spacer element, or a component configured to assist in physically positioning one or more other modules.

Figure 38 illustrates an appurtenance 3700, such as illustrated in Figure 37, in situ within a cavity wound 3200 in cross-section. The appurtenance 3700 in Figure 38 is a substantially planar, elongated structure packed within a cavity wound 3200. The appurtenance 3700 in Figure 38 includes a plurality of sensor units, which are distributed with the appurtenance 3700 within the cavity wound 3200. For purposes of illustration, the appurtenance 3700 is shown independently of a wound dressing. An appurtenance 3700 can be utilized, for example, with a wound dressing that is an alginate medicinal material coating the wound- facing surface 3350 of the appurtenance 3700. An

appurtenance 3700 can be placed, for example, in association with a wound dressing that is a medical gauze or bandage-like material that can be placed between the wound-facing surface 3350 of the appurtenance 3700 and the wound surface 3230. An appurtenance 3700 can be placed, for example, in association with a wound dressing that is a medical gauze or bandage-like material positioned adjacent to the cavity-facing surface 3340 of the appurtenance 3700. A wound dressing can be wet, for example saturated with water or saline solution. In the embodiment illustrated in Figure 38, the appurtenance 3700 is packed and entirely placed within the cavity 3220 of the wound 3200, i.e. there is no edge region of the appurtenance 3700 positioned adjacent to the surface 3240 of the periwound region. However, in some embodiments, an appurtenance 3700 includes an edge region that is positioned adjacent to the surface 3240 of the periwound region.

- I l l - Figure 38 illustrates that the cavity wound 3200 includes a section 3800 of the wound surface 3230 that provides or is subject to conditions that are distinct from the remainder of the wound surface 3230. For example, the section 3800 of the wound surface 3230 can include a bacterial infection, with the associated elevation in bacterial proteins provided in the section 3800. For example, if the section 3800 of the wound surface 3230 includes a bacterial infection, analytes that are markers of bacterial infection, such as bacterial proteins and immune response proteins, would be present at an elevated level in that section 3800. Some of these analytes would move to the adjacent section 3810 of the appurtenance 3700, such as through fluid flow through the porous substrate of the appurtenance 3700. Sensor units within the corresponding adjacent section 3810 of the appurtenance 3700 will detect the analytes flowing through the region. For example, the section 3800 of the wound surface 3230 can include a region that has been subject to increased physical pressure, for example through the actions of the patient, and therefore may include high levels of wound debris and a relatively low oxygen saturation. The corresponding adjacent section 3810 of the appurtenance 3700 would, therefore, be subject to similar local conditions. Sensor units on the adjacent section 3810 of the appurtenance 3700 will detect the local conditions. For example, if the section 3800 of the wound surface 3230 includes a region that is subject to physical pressure beyond a minimal level (e.g. 5 mm Hg or 10 mm Hg), the corresponding adjacent section 3810 of the

appurtenance 3700 will also be subject to the increased physical pressure. Sensor units within the corresponding adjacent section 3810 of the appurtenance 3700 will detect the increased physical pressure. In some embodiments, information regarding a detection can be transmitted from an associated transmitter. In some embodiments, the detection will cause a change in the sensor unit, such as an optically-detectable color change.

Figure 39 depicts an appurtenance 3700, such as shown in Figure 37. The appurtenance 3700 depicted in Figure 39 is an appurtenance 3700 that was packed and placed within a wound cavity, such as illustrated in Figure38, for a medically relevant period of time (e.g. 1 day, 2 days, 3 days, or 4 days), but has since been removed and placed on a substantially flat surface. The appurtenance 3700 in Figure 39 is a

substantially planar, elongated structure including a substrate 3710 with an array of attached sensor units 3320. At least some of the sensor units 3320 attached to the appurtenance 3700 shown in the embodiment depicted in Figure 39 include detectors with indicators that form visible color changes in the presence of a specific analyte. A section 3800 of the appurtenance 3700 includes sensor units 3320 that have detected the presence of one or more specific analytes, and the corresponding indicators of the sensor units have been activated. Figure 39 illustrates this with the sensor units 3320 in the section 3800 illustrated as colored markings. The three types of sensor units 3320A, 3320B and 3320C located in the section 3800 all indicate that they have detected the presence of their respective analytes. In some embodiments, the detectors in different types of sensor units can detect related analytes, such as proteins characteristic of a chronic wound, or an infection. In addition or alternatively, a sensor unit 3320 can include a detector of excessive wound exudate, or biomarkers indicating the presence of excessive levels of wound exudate. In addition or alternatively, a sensor unit 3320 can include a detector of excessive physical pressure with an indicator that forms visible color changes in the presence of excess pressure. For example, a sensor unit 3320 can include a detector of excessive physical pressure with a compartment of colored dye configured to rupture in the presence of excess pressure, creating a visible marking on the appurtenance 3700 at that location. The regionalized indicators of the appurtenance 3700 provide local information to a caregiver about the localized conditions of a wound region within a cavity wound (see, e.g. Figure38). Such a location within a cavity wound may not be easily visible or observable during wound care, and can assist medical caregivers to understand local wound conditions with the potential for altering the wound care plan if necessary.

In some embodiments, an appurtenance 3700 can be removed from a cavity wound and visually inspected for changes, such as the color changes illustrated in Figure 39. In some embodiments, an appurtenance 3700 is removed from a cavity wound and examined for changes in one or more sensor units with a detection device. For example, in some embodiments a sensor unit can include a detector that reflects a particular wavelength of light differently when an analyte from a cavity wound is detected. A detection device can include a transmitter of the appropriate light wavelength as well as a receiver to detect the reflection from the appurtenance. For example, in some embodiments a sensor unit can include a color indicator of a detection, and a detection device can emit light of a wavelength to detect the reflected color of the indicator. See, for example: US Patent Application Publication No. 2007/0269851, "Colorimetric Substrates, Colorimetric

Sensors, and Methods of Use," to Sanders et al; and US Patent Application Publication No. 2009/0299161, "Marker of Wound Infection," to Cullen et al, which are each incorporated by reference herein. For example, in some embodiments a sensor unit can include a passive RFID device, and a detection device can include an RFID transmitter and receiver.

Figure 40 depicts a region of an appurtenance 3700 to a wound dressing in cross- section. The appurtenance 3700 depicted includes two substrate layers 4000 A, 4000B. In some embodiments, a substrate of an appurtenance includes a plurality of layers. The substrate layers 4000A, 4000B are fabricated from fluid-permeable, substantially flexible materials that are durable under physiological conditions within a cavity wound over the time period of expected use of the appurtenance 3700. The combination of layers, 4000A, 4000B, create a substantially fluid-permeable appurtenance 3700. The substrate material is also bio-compatible with the cavity wound. The substrate material should not, for example, lead to an allergic reaction or severe inflammatory response under expected use conditions. The substrate material can, for example, be fabricated from non-allergenic or low toxicity materials, including hypoallergenic foam, nylon, or cotton. In some embodiments, the substrate layers 4000 A, 4000B within an appurtenance 3700 are fabricated from the same materials. In some embodiments, the substrate layers 4000A, 4000B within an appurtenance 3700 are fabricated from different materials. As shown in Figure 40, the two substrate layers 4000A, 4000B are affixed to each other at a surface of each of the substrate layers 4000A, 4000B. A series of sensor units 3320 are affixed within the substrate layers 4000 A, 4000B. For example, the substrate layers 4000 A, 4000B can be affixed to each other and to the sensor units 3320 with adhesive. For example, the substrate layers 4000A, 4000B can be affixed to each other and to the sensor units 3320 with fasteners. The sensor units 3320 can be of two or more types, and positioned within the appurtenance 3700 to form an array or pattern relative to the structure of the appurtenance 3700. For example, Figure 40 represents that the sensor units 3320 can include two types of sensor units 3320A, 3320B that are arranged as a sequential, repeating pattern within an array of sensor units 3320 (i.e. 3320A, 3320B, 3320A, 3320B ...). One or more layers 4000A, 4000B of the substrate of the appurtenance 3700 can include embedded structures configured to direct fluid to a surface of a sensor unit 3320. For example, a layer 4000 can include channels or grooves positioned to direct fluid flow between a region adjacent to the appurtenance 3700 and a surface of a sensor unit 3320. For example, a layer 4000 can include a plurality of unidirectional fluid flow structures positioned to direct fluid flow from a surface 3340, 3350 of the appurtenance 3700 to a surface of a sensor unit 3320. See, for example, US Patent No. 6,420,622 to Johnston et al., "Medical Article Having Fluid Control Film," which is incorporated herein by reference. The appurtenance 3700 includes a cavity wound-facing surface 3350 and a cavity-facing surface 3340. The cavity wound-facing surface 3350 can be configured for attachment of a primary wound dressing. The cavity-facing surface 3340 can be configured for attachment to a primary wound dressing. For example, a surface 3340, 3350 can include fastening units to secure a wound dressing relative to the appurtenance 3700 surface 3340, 3350.

Figure 41 illustrates aspects of a sensor unit 3320. The sensor unit 3320 is shown in a top-down viewpoint, or a similar viewpoint as in Figures 33 A, 37 and 39. A sensor unit 3320 is configured to be attached to an appurtenance to a cavity wound dressing. The sensor unit 3320 should, therefore, be of a size, mass and durability to be functional during use of the appurtenance. A sensor unit 3320 should be of a size, shape and mass to not place undue strain or physical stress on a wound surface of a cavity wound during use. The sensor unit 3320 includes an enclosure 4100. An enclosure 4100 can be fabricated from a material suitable to the embodiment, for example a soft plastic material. An enclosure 4100 can be fabricated from a biocompatible material, such as a medical grade silicone material. In some embodiments, the sensor unit 3320 is configured to be flexible, and the enclosure 4100 correspondingly fabricated from a flexible material. In some embodiments, the enclosure includes one or more deformable regions. In some embodiments, the enclosure includes one or more transparent regions. In some embodiments, the enclosure includes one or more translucent regions.

The sensor unit 3320 shown in Figure 41 includes a detector 4110 of physical pressure. The detector 4110 includes a deformable cover enclosing an interior space including a marker fluid 4115. The deformable cover is of a size, shape and flexibility to deform in the presence of physical pressure on the external surface of the detector 4110. Depending on the embodiment, the deformable cover in association with the enclosure 4100 of the sensor unit 3320 can be configured to deform in response to varying levels of physical pressure against the surface of the enclosure 4100 and the detector 4110. For example, the deformable cover of the detector 4110 can be configured to be compressed in response to physical pressure from the exterior of the sensor unit 3320 at a pressure level that is considered to be medically undesirable to a cavity wound. In some embodiments, the deformable cover of the detector 4110 is configured to compress at an external pressure of approximately 32 mm Hg. In some embodiments, the deformable cover of the detector 4110 is configured to compress at an external pressure of approximately 20 mm Hg. In some embodiments, the deformable cover of the detector 4110 is configured to compress at an external pressure of approximately 10 mm Hg. In some embodiments, the deformable cover of the detector 4110 is configured to compress at an external pressure of approximately 40 mm Hg.

The sensor unit 3320 includes a conduit 4120 connecting the interior of the detector 4110 and the interior of the indicator 4130. A marker fluid retention element 4125 is positioned within the conduit 4125 to retain the marker fluid 4115 within the detector 4110 when the deformable cover is not compressed. The marker fluid retention element 4125 is configured to allow marker fluid 4115 to move through the conduit 4120 in response to physical pressure from the deformable cover transmitted to the marker fluid 4115. The marker fluid 4115 can then enter the interior region of the indicator 4130.

Additionally or alternatively, other types of sensors of physical pressure, such as piezoelectric-based pressure sensors or capacitance-based pressure sensors, can be included in one or more sensor units. Some embodiments also include a sensor unit that includes an accelerometer.

Figure 42 illustrates aspects of a sensor unit 3320 such as shown in Figure 41. In the view shown in Figure 42, the deformable cover of the detector 4110 has been subject to physical pressure (depicted by the large arrow) and the cover has compressed, transmitting physical pressure to the marker fluid 4115. The physical pressure on the marker fluid 4115 has caused the marker fluid 41 15 to move through the conduit 4120 and into an interior region of the indicator 4115. The marker fluid retention element 4125 has permitted the flow of the marker fluid 4115 through the conduit 4120 in response to the physical pressure. For example, the marker fluid retention element 4125 can be configured to bend or flex away from the flow of marker fluid 4115, such as a flexible butterfly valve. For example, the marker fluid retention element 4125 can include a thin film configured to rupture in response to sufficient physical pressure from the marker fluid 4115. In some embodiments, the conduit 4120 includes a unidirectional flow structure. See, for example, US Patent No. 6,420,622 to Johnston et al., "Medical Article Having Fluid Control Film," which is incorporated herein by reference.

As shown in Figure 42, the marker fluid 4115 has moved through the conduit 4120 and into the interior region of the indicator 4130. The indicator 4130 is fabricated from a material that allows for observation of the marker fluid 4115 within the interior region of the indicator 4130. For example, if the marker fluid 4115 is a colored liquid, the indicator 4130 can be fabricated from a transparent or translucent plastic material. For example, if the marker fluid 4115 is a magnetic fluid, the indicator 4130 can be fabricated from a nonmagnetic material. For example, if the marker fluid 4115 is florescent, the indicator 4130 can be fabricated from a material that is transparent or translucent at the wavelength of the fluorescence. Correspondingly, a region of the enclosure 4100 adjacent to the indicator 4130 can be fabricated from a material that allows for observation of the marker fluid 4115 within the interior region of the enclosure and the indicator 4130. The indicator color can then be visualized by an outside observer. See, e.g. Figure 39.

Figure 43 illustrates aspects of a sensor unit 3320. The view illustrated in Figure

43 is a substantially top-down view, as seen from the top of a sensor unit 3320 looking down on to the unit. As shown in Figure 43, sensor unit 3320 includes a structural support 4300. The sensor unit 3320 illustrated includes a structural support 4300 configured to provide shape and support to the sensor unit 3320. The structural support 4300 can include, for example, a flexible plastic, which can be configured in a thin film or as a mesh of no more than a few millimeters (mm) in thickness. For example, the structural support 4300 can be no more than 3 mm, or no more than 5 mm, thick depending on the embodiment. The structural support 4300 can include, for example, a flexible paper material. The structural support 4300 can include, for example, a composite material. The structural support 4300 can include, for example, one or more materials with properties such as durability, strength, cost, weight, bio-compatibility and disposability that are suitable for a given embodiment. The structural support 4300 is configured to irreversibly attach to an appurtenance. In some embodiments, a sensor unit 3320 is modular and the structural support 4300 is configured to attach to a substrate of an appurtenance, such as with adhesive or barbed fasteners. For example, the structural support 4300 can include an adhesive material on the face configured to conform to the surface of the appurtenance. For example, the structural support 4300 can include one or more barbs, hooks or other projections on the face configured to conform to the surface of the appurtenance. The structural support 4300 can include, for example, a cover configured to seal the structural support 4300 to a substrate of an appurtenance. For example, the structural support 4300 can include a cover configured to prevent wetness, debris, dirt or microbial agents from travelling between the structural support 4300 and a substrate of an appurtenance. The sensor unit 3320 illustrated in Figure 43 includes a detector 4310 positioned within a conduit 4305. The conduit 4305 is configured to draw fluid, such as wound exudate, from the wound- facing side of the appurtenance, and therefore to draw analytes present in the wound fluid and/or wound exudate into the sensor unit 3320 in proximity to the detector 4310. The detector 4310 is configured to send a signal via wire connector 4315 to the indictor 4130 that includes a transmission unit 4380.

Also as illustrated in Figure 43, the sensor unit 3320 includes an indicator 4130 that includes a transmission unit 4380 attached to a surface of the structural support 4300. The transmission unit 4380 includes circuitry 4370 and at least one antenna 4320.

Although the transmission unit 4380 is illustrated as visible in Figure 43, in some embodiments all or part of the transmission unit 4380 will be covered and not be visible. The transmission unit 4380 is configured to transmit a signal. In some embodiments, the transmission unit 4380 is configured to transmit a signal in response to a received signal (e.g. as a passive RFID). In some embodiments, the transmission unit 4380 is configured to transmit a signal without having received a signal. For example, the transmission unit can be operably connected to a power source, such as a battery. As illustrated in Figure 43, an antenna 4320 can be a substantially planar antenna, such as commonly used in radio frequency identification (RFID) or near field communication (NFC) units. Prior to use, the antenna 4320 can be detuned with a removable surface layer of a conductive material. This can be desirable to reduce excess RFID signals, for example from appurtenances in storage prior to use. See US Patent No. 7,724,136 to Posamentier, titled "Revealable RFID Devices," which is incorporated herein by reference. The circuitry 4370 of the transmission unit 4380 can include a variety of components, as desired in a particular embodiment. The circuitry 4370 of the transmission unit 4380 can include a processor 4330. The circuitry 4370 can include non-volatile memory 4340. The circuitry 4370 can include a transmitter 4350. The circuitry 4370 can include one or more additional modules 1260. For example, the circuitry 4370 can include an energy source, such as a battery. For example, the circuitry 4370 can include a receiver. For example, the circuitry 4370 can include a transceiver. For example, the circuitry 4370 can include an additional antenna. For example, the circuitry 4370 can include volatile memory. The circuitry 4370 can include dielectric material configured to electrically interact with one or more antennas. See, for example, US Patent No. 7,055,754 to Forester, titled "Self- Compensating Antennas for Substrates Having Differing Dielectric Constant Values," which is incorporated herein by reference.

In some embodiments, an indicator that includes a transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate and a surface of the appurtenance. In some embodiments, the indicator that includes a transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on a surface of the appurtenance. In some embodiments, the indicator that includes a transmission unit can include a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate and a surface of the wound dressing. See, for example, US Patent Nos. 6,693,513 and 6,037,879 to Tuttle, titled "Wireless Identification Device, RFID Device with Push- On/Push-Off Switch, and Method of Manufacturing Wireless Identification Device," and US Patent No. 6,863,3320 to Selker, titled "Manually Operated Switch for Enabling and Disabling an RFID Card," as well as Sample et al., "A Capacitive Touch Interface for Passive RFID Tags," 2009 IEEE International Conference on RFID, 103-109 (2009), which are each incorporated herein by reference.

Figure 44 illustrates aspects of an appurtenance 4400 configured for use in a cavity wound. The appurtenance 4400 includes an edge region 3510, the edge region including a surface 3550 positioned to be adjacent with the surface region of the periwound region when the appurtenance 3330 is in use. The edge region 3510 also includes a surface 3560 positioned to be distal to the surface region of the periwound region when the

appurtenance 3330 is in use. The surface 3560 of the edge region 3510 of the

appurtenance 4400 includes an attached orientation indicator 3310. The surface 3560 of the edge region 3510 also includes a temperature sensor unit 3540. The temperature sensor unit 3540 is configured to detect the temperature of a surface region of the periwound region when the appurtenance 3330 is in use. See US Patent No. 6,963,772, and US Patent Application Publication No. 2006/0047218, each titled "User-Retainable Temperature and Impedance Monitoring Methods and Devices," each to Bloom, which are each incorporated by reference. The temperature sensor unit 3540 can be configured to detect the temperature of a surface region of the periwound region. Detected temperature information can, for example, be recorded, such as in an associated memory device, over time. Detected temperature information can, for example, be transmitted by an associated transmission unit. For example, the temperature sensor unit 3540 record can be configured for use in comparison with a temperature record from a sensor unit attached to the substrate positioned within a wound cavity.

The appurtenance 4400 shown in Figure 44 includes a substrate including a structural side wall 4440 and a structural lower wall 4420, the structural side wall 4440 and the structural lower wall 4420 configured to conform in shape with an interior of a cavity of a cavity wound. The structural side wall 4440 and the structural lower wall 4420 illustrated in Figure 44 are in a substantially cylindrical shape, to conform with a substantially cylindrical cavity wound. The structural side wall 4440 and the structural lower wall 4420 form an interior space 4430 of the appurtenance 4400. Other

configurations are possible to conform with the shapes of cavity wounds of non- cylindrical shapes. For example, an appurtenance can be configured as a circular, oblong, or irregular shape. In the embodiment illustrated in Figure 44, the appurtenance is fabricated from a flexible but substantially firm material, configured to substantially retain its size and shape during use in a cavity wound. The structural side wall 4440 and the structural lower wall 4420 include a plurality of apertures 4410 penetrating from the wound-facing surface 3350 of the appurtenance 4400 to the cavity- facing surface 3340. Although five apertures 4410 are illustrated, in some embodiments there will be fewer than five or greater than five apertures 4410. In some embodiments, the apertures are positioned on regions of the appurtenance 4400 corresponding to regions of the cavity wound surface where enhanced monitoring is desirable. For example, a region of a cavity wound surface adjacent to a bone may require closer monitoring than other regions of the cavity wound surface, and an appurtenance can include apertures in the region

corresponding to the cavity wound surface adjacent to the bone. For example, a region of a cavity wound surface adjacent to a region that has been bleeding may require closer monitoring than other regions of the cavity wound surface, and an appurtenance can include apertures in the region corresponding to the cavity wound surface at the recently bleeding, and therefore fragile, region of the cavity wound surface.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures; and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures.

In some embodiments, a substrate to an appurtenance includes a structure including the wound-facing surface of a size and shape to approximate the surface of the cavity wound with a gap between the wound-facing surface of the substrate and a cavity wound surface. In some embodiments, a substrate to an appurtenance includes a three dimensional structure with at least one wound-facing surface, the at least one wound- facing surface of a size and shape to reversibly mate with the wound surface of the cavity wound. In some embodiments, a substrate to an appurtenance includes a non-porous, flexible structure. For example, the substrate can be fabricated from a non-porous medical grade silicone. In some embodiments, a substrate to an appurtenance includes a porous, flexible structure. For example, the substrate can be fabricated from a medical grade silicone including a plurality of pores through the substrate. In some embodiments, a substrate to an appurtenance includes an interior region within the substrate, the interior region including one or more of the plurality of sensor units. In some embodiments, a substrate to an appurtenance includes a plurality of unidirectional fluid flow structures attached to the apertures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound- facing surface to one or more of the plurality of sensor units attached to the substrate.

In some embodiments, the plurality of sensor units attached to the substrate include a plurality of sensor units of at least two distinct types oriented as a pattern relative to the wound-facing surface. For example, the plurality of sensor units can be oriented in a "checkerboard" pattern, or an alternating array. In some embodiments, the plurality of sensor units attached to the substrate include a plurality of sensor units including at least one sensor unit configured to detect physical pressure or temperature over time. For example, the at least one sensor unit configured to detect physical pressure or temperature over time can be configured to detect physical pressure or temperature over minimum threshold values. For example, the at least one sensor unit configured to detect physical pressure or temperature over time can be configured to indicate a composite value for detected physical pressure or temperature.

In some embodiments, the plurality of sensor units attached to the substrate include at least one antenna operably attached to at least one sensor unit. In some embodiments, the plurality of sensor units attached to the substrate include at least one chemical-based sensor unit. In some embodiments, the plurality of sensor units attached to the substrate include at least one positional indicator. In some embodiments, the plurality of sensor units attached to the substrate include at least one fluid-activated sensor unit. In some embodiments, the plurality of sensor units attached to the substrate include at least one sensor unit including an optically resolvable detection indicator. For example, a sensor unit can include an indicator that changes color after detection of a condition, such as the presence of an analyte. In some embodiments, the plurality of sensor units attached to the substrate include at least one sensor unit including a detection indicator with an RFID antenna.

In some embodiments, an appurtenance includes: an edge region of the

appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one orientation indicator attached to the edge region. In some embodiments, an appurtenance includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one temperature sensor unit attached to the edge region. For example, a temperature sensor unit can be configured to detect the surface temperature of the periwound region. In some embodiments, an appurtenance is functional when wet. For example, an appurtenance can be configured for use within a substantially damp wound cavity. For example, an appurtenance can be configured for use with a saline-soaked gauze primary dressing. For example, an appurtenance can be configured for use with a primary dressing including a hydrogel. In some embodiments, an appurtenance includes: a wound dressing, the wound dressing configured to be positioned within the wound cavity between the appurtenance and the wound surface; and a second wound dressing, the second wound dressing configured to cover a wound region and stabilize the appurtenance and the wound dressing during use, the second wound dressing configured to be removable from the wound region after use. In some embodiments, an appurtenance includes: a detachable cover configured to reversibly mate with the at least one wound- facing surface of the substrate.

Figure 45 illustrates aspects of an appurtenance 4400 such as the one illustrated in Figure 44, depicted in vertical cross-section. The structural side wall 4440 and the structural lower wall 4420 are shown in vertical section to illustrate the interior space 4430 of the appurtenance 4400. A plurality of apertures 4410 are positioned on the structural side wall 4440, the apertures 4410 positioned to allow fluid flow from the wound-facing surface of the appurtenance to the cavity-facing surface 3340. Each of the apertures 4410 has a corresponding sensor unit 4500 associated with the aperture 4410, each of the sensor units 4500 affixed to the cavity-facing surface 3340. In the embodiment illustrated, the apertures 4410 are positioned and sized to allow fluid flow directly from the wound surface region to the sensor units 4500 attached to the cavity-facing surface 3340 of the appurtenance 4400. The sensor units 4500 can include, for example, a detector positioned within a conduit. See, e.g. Figure 43. This embodiment can, for example, be used with a primary dressing within the interior space 4430 of the appurtenance 4400. Medicament, such as saline solution or alginate, can move across the porous structure of the structural side wall 4440 and the structural lower wall 4420 of the appurtenance 4400. Analytes from the wound surface will be detected regionally by each of the sensor units 4500 respectively affixed to the cavity-facing surface 3340 in specific locations. This regional information can be useful to a caregiver, such as medical personnel, for monitoring therapy response by the cavity wound.

Figure 46 illustrates a cross-section view of an embodiment of an appurtenance

4400 in situ within a cavity wound 3200. The embodiment illustrated in Figure 46 is similar to that shown in Figures 44 and 45, shown in Figure 46 in situ within a cavity wound 3200. Figure 46 depicts that a wound dressing 3400 is positioned within the cavity wound 3200, adjacent to the wound surface 3230. The appurtenance 1300 is positioned adjacent to the wound dressing 3400 within the cavity wound 3200. In the illustrated embodiment, the appurtenance 4400 includes a plurality of apertures 4410. Each of the apertures 4410 has a corresponding sensor unit 4500 associated with the aperture 4410, each of the sensor units 4500 affixed to the cavity-facing surface 3340 of the appurtenance 4400. In the embodiment illustrated, each of the sensor units 4500 is positioned to detect and indicate the conditions, such as the presence of analytes, in the wound fluid and wound dressing fluid from the adjacent region of the wound dressing 3400 and wound surface 3230.

Figure 47A illustrates aspects of a cavity wound 3200 on a body part 3210. As represented generally in Figure 47A, in some medical situations a cavity wound 3200 forms on the weight-bearing region of a body part 3210, such as a heel. A cavity wound 3200 on the weight-bearing region of a body part 3210 can be further exacerbated by additional pressure, represented by force 4700, against the cavity wound 3200. For example, the force 4700 can impede blood flow through the adjacent blood vessels, including through closure of capillaries. Medical caregivers often suggest reduced pressure for such wounds, but are unable to monitor the pressure received by the cavity wound over time during treatment with a conventional primary dressing. Some patients, such as those suffering from diabetic neuropathy, are unable to feel the pressure on the wound and, therefore, unwittingly damage the wound through routine activities that result in prolonged physical pressure at the cavity wound 3200 site.

Figure 47B shows a cross-section view of an embodiment of an appurtenance 4400 in situ in a cavity wound 3200. The appurtenance 4400 includes an edge region 3510 positioned adjacent to the periwound surface 3240 in situ. The cavity wound 3200 includes a wound dressing 300 positioned within the cavity wound 3200 adjacent to the wound surface 3230. The appurtenance 4400 includes a plurality of sensor units 4500 configured to detect analytes, the sensor units 4500 attached to the interior surface 240 of the appurtenance 4400. Each of the sensor units 4500 is positioned adjacent to an aperture 4410 in the appurtenance 4400, the each of the apertures 4410 of a size, shape and position to allow fluid to flow through the appurtenance 4400 structure. In the embodiment illustrated, the appurtenance 4400 is fabricated from a substantially flexible material, the material capable of transmitting physical pressure from the body part 3210 through the wound surface 3230 to the appurtenance 4400. Attached to the appurtenance 4400 are a plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200. The plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can include, for example, one or more detectors of physical pressure. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at capillary-closing levels, which can inhibit blood flow in the body part 3210 and decrease physiological wound healing. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at a level greater than 20 mm Hg. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at a level greater than 15 mm Hg. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at a level greater than 30 mm Hg. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at a level greater than 35 mm Hg. For example, the plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure at a level greater than 40 mm Hg. The plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure over multiple time points and indicate a time-dependent pressure result. The plurality of sensor units 4710 configured to detect physical pressure within the cavity wound 3200 can be configured to detect physical pressure over time and indicate the composite, average, or total pressure. In some embodiments, each of the plurality of sensor units 4500, 4710 indicate their own distinctive detection events. In some embodiments, each of the plurality of sensor units 4500, 4710 are connected to a common reporter unit that records and reports on the detection, or lack thereof, for each of the sensor units 4500, 4710.

In some embodiments, the appurtenance includes: a sensor unit including one or more detectors; an indicator including a transmission unit with a processor and at least one transmitter unit operably attached to the processor; and a connector between the sensor unit and the transmission unit, the connector configured to convey signals between the one or more detectors and the transmission unit. For example, the connector can include a wire. In some embodiments, the sensor unit is positioned adjacent to an opening in the appurtenance, the opening at a position to allow analytes to flow from the wound surface into a position in contact with the sensor unit.

In some embodiments, the sensor unit can be configured to be responsive to changes in circuitry capacitance. For example, in some embodiments the sensor unit is operably attached to a transmission unit via one or more connectors including wires. The transmission unit can include, for example, one or more antennas, a non-volatile memory, and related circuitry. The transmission unit can include, for example, an antenna and a receiver operably attached to the antenna. The transmission unit can include, for example, non-volatile memory. The transmission unit can include, for example, a substrate including at least one surface configured to conform to a surface of an appurtenance. For example, the transmission unit can, in whole or part, be attached to a cavity-facing surface of an appurtenance. The transmission unit can, in whole or part, be attached to an exterior surface of the edge region of the appurtenance. For example, in some situations the appurtenance is too small to accommodate the square area of the transmission unit, or where other space parameters make that option desirable. In some embodiments of an appurtenance, the transmission unit including at least one antenna is positioned adjacent to the periwound region, it can be desirable to include a self-compensating antenna system, such as described in US Patent No. 7,055,754 to Forester, titled "Self-Compensating Antennas for Substrates having Differing Dielectric Constant Values," which is incorporated herein by reference. In some embodiments, the appurtenance can include an indicator operably attached to the transmission unit. For example the appurtenance can include an indicator which is at least one of: a visual indicator, a haptic indicator, or an auditory indicator.

Figure 48 illustrates aspects of a system including a cavity wound 3200 with an appurtenance 3320 associated with a wound dressing. As shown in Figure 48, a wound dressing with an associated appurtenance is placed over and within a cavity wound 3200 on a body part 3210 of a patient. For example, the body part 3210 may have been subject to a surgery, and therefore to have an acute wound closing by primary intention. For example, the body part 3210 can include an ulcer, and therefore have a chronic wound closing by secondary or tertiary intention. The appurtenance 3320 associated with the wound dressing receives signals 4840 sent from a local unit 4810 and transmits signals 4850 to the local unit 4810. For example, the appurtenance 3320 associated with the wound dressing can include a passive RFID configured to transmit signals 4850 after receiving signals 4840 from a proximal RFID reader device in the local unit 4810. The appurtenance 3320 includes at least one transmission unit connected to a sensor unit. The local unit 4810 includes a receiver for the at least one transmission unit, at least one processor operably attached to the receiver, and at least one communication unit operably attached to the processor.

A local unit 4810 can include a handheld device. For example, the local unit 4810 can include a distinct handheld device. For example, the local unit 4810 can be included as part of a larger handheld unit, for example a tablet, a laptop, a cell phone, a personal communication device, or similar types of devices. A local unit 4810 can be integrated with an institutional furnishing, such as a hospital bed, a medical stand, a bedside table or a surgical cart. A local unit 4810 can be of a size, a shape and a configuration for portable handheld use. A local unit 4810 can be configured to be attached to a mobile unit, such as the end of a hospital bed, a medical stand, a bedside table, a wheelchair, or similar device. For example, a local unit can be integrated with a medical cart, as described in US Patent No. 7,667,606 to Packert et al., titled "RF Enabled Surgical Cart and Use of Same in Operating Room Environment," which is incorporated herein by reference. A local unit 4810 can be configured to be integrated into a furnishing. For example, a local unit 4810 can be integrated into a hospital bed, a bedside hospital monitor, a bedside table, a medical chair, a medical table, or similar furnishing. A local unit 4810 can be a wearable device, such as in association with a wristband, a waistband, or a strap. A local unit 4810 can be integrated with a wearable device used in conjunction with the appurtenance 3320 and a wound dressing, such as a local unit integrated with a cover or wrapping placed over the cavity wound 3200. A local unit 4810 can be a wearable device integrated into a wearable object, for example a vest or an armband. A local unit 4810 can be configured for integration into a wearable object for use by a patient, for example a vest worn by a patient with a cavity wound 3200.

A local unit 4810 can include a display unit 4820. In some embodiments, there can be a secondary device configured to relay signals to the local unit 4810, for example as described in US Patent No. 7,986,235 to Posamentier titled "RFID Receive- Only

System," which is incorporated herein by reference. A local unit 4810 can include a communication unit configured to send signals to a central assembly. The communication unit of a local unit 4810 can include at least one of: a visual display, a sound generator, a vibrating unit, and one or more light displays. A local unit 4810 can include at least one user interface, such as a screen, monitor, touchscreen or voice recognition element. A local unit 4810 can include an auditory signal generator. A local unit 4810 can include an input device 4830, for example a keyboard. Although the local unit 4810 illustrated in Figure 48 includes a keyboard as an input device 4830, in some embodiments the input device 4830 can include other types of input devices, for example a touchscreen, stylus, keypad, or voice recognition system. A local unit 4810 can include a power source. For example, a local unit 4810 can include a solar cell, a battery or connect to a building power supply through a wire connection. A user 4800 operates the local unit 4810.

A user 4800 can include a medical caregiver, such as a nurse or doctor, or a patient, patient family member or other individual monitoring the wound dressing.

Although user 4800 is shown/described herein as a single illustrated figure, the user 4800 can be representative of a human user, a robotic user (e.g., computational entity), and/or substantially any combination thereof (e.g., a user can be assisted by one or more robotic agents) unless context dictates otherwise. In general, the same can be said of "sender" and/or other entity -oriented terms as such terms are used herein unless context dictates otherwise. A user 4800 may utilize a local unit 4810 through a user interface, for example one or more buttons, a keyboard, a touchscreen, a voice recognition device, a stylus, or other means.

A local unit 4810 can include a communication device including at least one transmitter. A local unit 4810 can include a radio-frequency identification (RFID) receiver. A local unit 4810 can include a near field communication (NFC) device. A local unit 4810 can be configured to send and receive signals from a plurality of appurtenances. For example, a local unit 4810 can be configured to send and receive signals from multiple appurtenances affixed to wound dressings on a single individual. For example, a local unit 4810 can be configured to send and receive signals from multiple appurtenances affixed to wound dressings on multiple individuals in a defined area, such as a single room or region of a room. A local unit 4810 can be configured to send signals to one or more

appurtenances 3320 associated with cavity wound dressings automatically. For example, local unit 4810 can be configured to send signals to one or more appurtenances 3320 associated with cavity wound dressings at least one of: every 30 minutes; every hour; every 2 hours; or every 3 hours. A local unit 4810 can be configured to send signals to one or more appurtenances 3320 associated with cavity wound dressings on a schedule selected by the user 4800. For example, local unit 4810 can be configured to send signals to one or more appurtenances 3320 associated with cavity wound dressings on at least one of: an hourly schedule; a schedule of every 30 minutes for 4 hours, followed by hourly signals; or a schedule provided by the user through the user interface (e.g. the keyboard 4830). A local unit 4810 can be configured to send signals to one or more appurtenances 3320 associated with cavity wound dressings on a preset schedule which is selected by the user 4800. For example, local unit 4810 can be configured to send signals to one or more appurtenances 3320 associated with cavity wound dressings on at least one of: a schedule preset to monitor a wound after surgery; a schedule preset to monitor a chronic wound; an hourly schedule; a schedule of every 2 hours; a schedule of hourly during the day and every 2 hours at night; or other preset schedules.

The signals 4840 sent from the local unit 4810 to the appurtenances 3320 associated with cavity wound dressings can be radio frequency signals in a particular wavelength, or range of wavelengths. For example, the signals can be in the UHF range, such as a UHF sub-range commonly used in a particular geographic region. See, for example the "Worldwide RFID UHF Map" by Intellef ex Corporation (©2009), which is incorporated herein by reference. For example, the signals can be in a range of 902-928 MHz. For example, the signals can be in a range specified by an industry standard. For example, the signals can be in the approximately 13.56 megahertz (MHz) range, or within the ISO 14443 standard parameters. For example, the signals can be in the IEEE 802.1 lx standard or the Bluetooth standard range. See, for example, US Patent No. 7,215,976 to Brideglall, titled "RFID Device, System and Method of Operation Including a Hybrid Backscatter-based RFID Protocol Compatible with RFID, Bluetooth and/or IEEE 802.1 lx Infrastructure," which is incorporated herein by reference. For example, the signals can be in the approximately 131 kilohertz (KHz) range, for example as part of a RuBee™ (IEEE standard 1902.1) system (equipment sold, for example, by Visible Assets™, Inc). See for example: the description of RuBee™ systems from the Visible Assets™ webpage; Stevens et al, "RuBee (IEEE 1902.1) - The Physics Behind, Real-Time, High Security Wireless Asset Visibility Networks in Harsh Environments," a white paper from Visible Assets™; and in US Patent Application No. 2007/0171076 to Stevens and Waterhouse, titled "Low- frequency Radio Tag Encapsulating System," each of which are incorporated herein by reference.

Similarly, the signals 4850 sent from the appurtenance 3320 associated with a cavity wound dressing to the local unit 4810 can be one of the types described above in relation to signals 4840 sent from the local unit 4810. In some embodiments, the appurtenance 3320 associated with a cavity wound dressing includes a backscatter or reflective transmission device, and so the signals 4850 sent from the appurtenance 3320 associated with the cavity wound dressing to the local unit 4810 can be backscatter or reflective signals. For example, as described in "Fundamental Operating Principles," in Chapter 3 of the RFID Handbook: Fundamentals and Applications in Contactless Smart Cards and Identification, Klaus Finkenzeller, John Wiley & Sons, (2003), which is incorporated herein by reference herein.

The signals 4840 transmitted from the local unit 4810 or the signals 4850 transmitted from the appurtenance 3320 associated with a cavity wound dressing can be sent in a fixed direction from the signal source. The appurtenance 3320 and the local unit 4810 may each include markings or other visible aspects directing a user how as to orient the appurtenance 3320 and the local unit 4810 relative to each other for signal

directionality. For example, an appurtenance 3320 can include a positional identifier on an edge region. For example, an appurtenance 3320 can include an orientation marker on an edge region.

In many embodiments, it is envisioned that the signal strength of a signal 4840 transmitted from the local unit 4810 or a signal 4850 transmitted from an appurtenance 3320 will be such that the signal 4840, 4850 will not travel a significant distance. The local unit 4810 and the appurtenance 3320 may, therefore, need to be placed in reasonably close proximity for signals 4840, 4850 to travel between the devices. For example, the signal 4840, 4850 transmitted from either the local unit 4810 or transmitted from the appurtenance 3320 can be such that the receiver of such signals should be within the same room. For example, the signal 4840, 4850 transmitted from either the local unit 4810 or transmitted from the appurtenance 3320 can be such that the receiver of such signals should be within 10 feet. For example, the signal 4840, 4850 transmitted from either the local unit 4810 or transmitted from the appurtenance 3320 can be such that the receiver of such signals should be within 3 feet.

Figure 49 illustrates aspects of a system including an appurtenance 3330 used to monitor a cavity wound 3200. As illustrated in Figure 49, an appurtenance 3330 is positioned relative to a cavity wound 3200 on a body part 3210 of a patient. The appurtenance 3330 sends and receives signals 4840, 1750 from a local unit 4810. The local unit 4810 can be utilized by a user 4800.

Figure 49 illustrates aspects of the local unit 4810. The local unit 4810 includes a housing, with connected user interface and input components (e.g. a display and keyboard). The local unit 4810 can include a processor 4900. The local unit 4810 can include memory 4910. The memory 4910 can include, for example, volatile and/or nonvolatile memory. The local unit 4810 can include at least one antenna 4920. The local unit 4810 can include circuitry 4930, operably connected to the other components of the local unit 4810. The local unit 4810 can include one or more transmitters 4940. The local unit 4810 can include one or more receivers 4950. The local unit 4810 can include one or more power sources 4960, such as a battery, a solar cell, or a plug-in socket. The local unit 4810 can include logic 4970. The local unit 4810 can include other components 4980, 4990 as appropriate to a specific embodiment. The local unit 4810 can include, for example, an application specific intelligent microsensor as described in US Patent No. 6,889,165 to Lind et al, titled "Application Specific Intelligent Microsensors," which is incorporated herein by reference herein. The local unit 4810 can include, for example, a distinct identification signal. The local unit 4810 can include, for example, a visible indicator, such as a light. The local unit 4810 can include, for example, an identification code specific to that local unit 4810.

Figure 50 shows aspects of a system including an appurtenance 3330 to a cavity wound 3200 dressing. As shown in Figure 50, an appurtenance 3330 is positioned relative to a cavity wound on a body part 3210 of a patient. The appurtenance 3330 associated with the wound 3200 sends and receives signals 4840, 4850 from a local unit 4810. The local unit 4810 can be utilized by a user 4800.

Also as shown in Figure 50, the local unit 4810 can send and receive signals 5005, 5010 from a central assembly 5005. The local unit 4810 can send and receive signals 5005, 5010 with a wireless connection, as shown in Figure 50, or can send and receive signals 5005, 5010 through a wire connection. A central assembly 5005 includes at least one user interface device (e.g. a keyboard, touchscreen, display, etc.) which can be utilized by a system user 5000. A system user 5000 can include a medical caregiver, such as a nurse or doctor, or a patient caregiver, or a patient him- or herself, or other individual monitoring the wound dressing. Although system user 5000 is shown/described herein as a single illustrated figure, the system user 5000 can be representative of a human user, a robotic user (e.g., computational entity), and/or substantially any combination thereof (e.g., a user can be assisted by one or more robotic agents) unless context dictates otherwise. In general, the same can be said of "sender" and/or other entity-oriented terms as such terms are used herein unless context dictates otherwise.

Figure 50 illustrates aspects of some embodiments of a central assembly 5005. A central assembly can be located primarily or mainly in one or a limited number of machines, for example one or more computer servers. A central assembly 5005 can interface with, or include, a 2G-RFID-Based E-Healthcare system. See, for example,

Chen et al, "A 2G-RFID-Based E-Healthcare System," IEEE Wireless Communications, February 2010, pages 37-43, which is incorporated herein by reference. A central assembly 5005 can interface with, or include, a digital management system, for example as discussed in: Fisher, "Indoor Positioning and Digital Management: Emerging

Surveillance Regimes in Hospitals" in T. Monahan (Ed), Surveillance and Security:

Technological Politics and Power in Everyday Life (pp. 77-88), New York: Routledge (2006); and Fisher and Monahan, "Tracking the Social Dimensions of RFID Systems in Hospitals," International Journal of Medical Informatics 77 (2008) 176-183, which are each incorporated herein by reference. A central assembly 5005 can interface with, or include, a drug tracking system, as described, for example, in "RFID Systems for

Pharmaceutical Distributors to Meet the New FDA Regulations on Drugs," white paper from Abhisam Software, 2006, which is incorporated herein by reference. The central assembly 5005 can include, for example, at least one transmitter 5020. The central assembly 5005 can include, for example, at least one receiver 5025. The central assembly 5005 can include, for example, at least one antenna 5030. The central assembly 5005 can include, for example, memory, which can include non- volatile memory or volatile memory. The central assembly 5005 can include, for example, circuitry 5040. The circuitry 5040 can be operably connected to other components of the central assembly 5005. The central assembly 5005 can include, for example, a power source 5045. A power source 5045 can include, for example, at least one battery, a plug-in connection, a wireless power source, or a solar cell. The central assembly 5005 can include, for example, a processor 5050. The central assembly 5005 can include, for example, logic 5055. The central assembly 5005 can include, for example, additional components 5060, 5065.

Figure 51 illustrates aspects of a system including an appurtenance 3330 used in association with a cavity wound 3200 dressing. As illustrated in Figure 51, an

appurtenance 3330 is used in association with a cavity wound 3200 dressing on a body part 3210 of a patient. The appurtenance 3330 used in association with a cavity wound 3200 dressing sends and receives signals 4840, 4850 from a local unit 4810. The local unit 4810 sends and receives signals 5180, 2085 from a central assembly 5105. The central assembly 5105 illustrated in Figure 51 is in a "cloud" format, with a significant portion of its components distributed on a computer network, or a network of computing devices. The central assembly 5105 is configured to communicate with one or more interface devices, for example an individual computer. In some embodiments, the central assembly 5105 is configured to communicate directly with an appurtenance 3330.

Depending on the embodiment, a cloud-based central assembly 5105 can include a plurality of components as illustrated in Figure 51. For example, a central assembly 5105 can include logic 5110. For example, a central assembly 5105 can include circuitry 5120. The circuitry 5120 can be operably connected to other components of the central assembly 5105. For example, a central assembly 5105 can include memory 5130. For example, a central assembly 5105 can include one or more power sources 5140. For example, a central assembly 5105 can include at least one processor 5150. For example, a central assembly 5105 can include other components 5160.

Also as illustrated in Figure 51, a central assembly 5105 can communicate with a remote device 5190 through signals 5170, 5175. Signals 5170 can be sent and signals 5175 can be received by an aspect of the central assembly 5105. Signals 5175 can be sent and signals 5170 can be received by the remote device 5190. Although the signals 5170, 5175 illustrated in Figure 51 are wireless signals, in some embodiments the central assembly 5105 and a remote device 5190 can communicate through a wired connection. The remote device 5190 can be, for example, a pager, cell phone, laptop, PDA, tablet, smart phone or other device. The remote device 5190 can be, for example, incorporated into a wearable item. The remote device 5190 can be operated by a remote system user 5195. Some embodiments include a plurality of remote devices 5190, which can be operated by a plurality of remote system users 5195. The remote system users 5195 can include, for example, a care provider, medical personnel, a healthcare provider, and/or the patient.

In some embodiments, an appurtenance for monitoring a cavity wound comprises: a substrate configured to associate with a cavity wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry; a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch. For example, the substrate can be fabricated as a substantially planar, flexible structure. For example, the substrate can be fabricated as a three-dimensional structure configured to be placed within the cavity of a cavity wound in association with a primary dressing. For example, the substrate can be configured to irreversibly attach to a primary cavity wound dressing.

Some appurtenances to a cavity wound include a transmission unit. In some embodiments, the transmission unit can include a transmitter unit and a receiver. In some embodiments, the transmission unit is configured to transmit a signal in response to an interrogation signal. A transmission unit can include a radio frequency identification (RFID) device. A transmission unit can include a passive radio frequency identification (RFID) device. A transmission unit can include an active radio frequency identification (RFID) device. A transmission unit can include a Near Field Communication (NFC) device. A transmission unit can include non-volatile memory. A transmission unit can include volatile memory. A transmission unit can include a processor. A transmission unit can include a battery.

Some embodiments include an appurtenance including a selectively-actuatable switch. For example, the selectively actuatable switch can include a connector between the transmission unit and the one or more sensor units. For example, the selectively actuatable switch can include a physical conduit configured to allow a liquid to flow through the appurtenance to a location in contact with the at least one antenna of the transmission unit. For example, the selectively actuatable switch can include a wire connecting the transmission unit and the one or more sensor units. In some embodiments, the selectively actuatable switch is configured as a binary switch. In some embodiments, the selectively actuatable switch is configured to be irreversible. In some embodiments, the selectively actuatable switch is configured to be responsive to a change in capacitance.

Some embodiments include one or more sensor units affixed to a substrate and operably connected to a selectively actuatable switch. In some embodiments, the one or more sensor units include a plurality of sensor units of at least two distinct types oriented as a pattern relative to the wound-facing surface. For example, the sensor units can be oriented in a repeating array. For example, the sensor units can be oriented relative to the expected structure of the wound surface that will be adjacent to the wound-facing surface during use of the appurtenance. In some embodiments, the one or more sensor units include at least one sensor unit configured to detect physical pressure or temperature over time. For example, at least one sensor unit can be configured to detect physical pressure or temperature above preset minimum values. For example, at least one sensor unit can be configured to detect physical pressure or temperature and indicate a combined value for the two detected parameters. In some embodiments, the one or more sensor units include at least one antenna operably attached to at least one sensor unit. In some embodiments, the one or more sensor units include at least one chemical-based sensor unit. See, for example: US Patent No. 7,951,605 to Pitner et al, "Multianalyte Sensor;" US Patent Application No. 2011/0082356 to Yang et al., "Analyte Sensor Apparatuses Having Interference Rejection Membranes and Methods for Making and Using Them;" US Patent Application No. 2010/0331634 to Muller et al, "Hydrogel Implant for Sensing

Metabolites in Body Tissue;" and US Patent No. 7,964,390 to Rozakis, "Sensor System;" which are each incorporated by reference herein. For example, a chemical-based sensor unit can include a chemical-based detector. For example, a chemical-based sensor unit can include a chemical-based indicator, such as a chemical-based indicator including a color changing chemical. In some embodiments, the one or more sensor units include at least one positional indicator. For example, a positional indicator can indicate the relative distance of the sensor unit from an edge region of the appurtenance. For example, a positional indicator can indicate the position of the appurtenance relative to its expected depth in the cavity of the cavity wound during use. In some embodiments, the one or more sensor units include at least one fluid-activated sensor unit. For example, a sensor unit can be activated in the presence of fluid flow through an aperture in the appurtenance into an interior region of the sensor unit. In some embodiments, the one or more sensor units include at least one sensor unit including an optically resolvable detection indicator. For example, a sensor unit can include a visible detection indicator, such as a visible color change or an LED that can be illuminated as an indicator. For example, a sensor unit can include an optically resolvable detection indicator that can be resolved with an external optical device, such as an external device with a light source in the ultraviolet (UV) range, or a light source for light of a specific wavelength (e.g. a wavelength matched to the excitation energy characteristics of a chemical present in the sensor unit that has its properties altered by the presence of an analyte. In some embodiments, the one or more sensor units include at least one sensor unit including an indicator with an RFID antenna. For example, a sensor unit can be configured to send an RFID signal in response to the detection of an analyte. For example, a sensor unit can be configured to respond to a RFID signal in a specific manner after the detection of an analyte.

Some embodiments include an appurtenance including: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one orientation indicator attached to the edge region. For example, an orientation indicator can be an external marking visible to a caregiver. For example, an orientation indicator can be a nonvisible marking that is detectable by an external device, such as in the presence of a specific wavelength of light. In some embodiments, an orientation indicator includes both a visible and a nonvisible marking. An orientation indicator that includes a nonvisible marking can be used, for example, to orient the appurtenance after use when the appurtenance is being scanned by an external device to capture information from the indicators in the sensor units attached to the appurtenance. Some embodiments include an appurtenance including: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one temperature sensor unit attached to the edge region. For example, a temperature sensor attached to an edge region of an appurtenance can be configured to detect ambient temperature around the cavity wound. For example, a temperature sensor attached to an edge region of an appurtenance can be configured to detect the surface temperature of the patient in the periwound region.

Some embodiments include: a wound dressing, the wound dressing configured to be used in association with the appurtenance; and a second wound dressing, the second wound dressing configured to cover a wound region and stabilize the appurtenance and the wound dressing during use, the second wound dressing configured to be removable from the wound region after use. For example, an appurtenance can be distributed as a kit, packaged with a primary and a secondary dressing configured for use together with the appurtenance. In some embodiments, the appurtenance is functional when wet, for example in the presence of a saline-dampened wound dressing. In some embodiments, the appurtenance is functional when wet, for example for use in a physiologically damp wound cavity. Some embodiments include a detachable cover configured to reversibly mate with at least one wound-facing surface of the substrate. For example, a detachable cover can include a thin plastic film configured to reversibly affix to at least one wound- facing surface of the substrate of the appurtenance, and to be removed prior to use of the appurtenance. In some embodiments, the appurtenance is substantially sterilized prior to use. For example, the appurtenance can be substantially sterilized prior to inclusion in a cavity wound dressing medical kit. For example, the appurtenance can be substantially sterilized along with other components of a cavity wound dressing medical kit.

In some embodiments, the appurtenance includes a selectively actuatable switch operably connected to a transmission unit. Some embodiments also include an indicator operably attached to the selectively actuatable switch. For example, an indicator can include an LED attached to an edge region of the appurtenance. Some embodiments include a battery. Some embodiments include a processor and a transceiver. In some embodiments, the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on at least one sensor unit. In some embodiments, the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on the wound-facing surface of the appurtenance. For example, the pressure sensitive activation region can be configured to activate the transmission unit in the presence of physical pressure above 30 mm Hg in the region adjacent to the wound surface. For example, the pressure sensitive activation region can be configured to activate the transmission unit in the presence of physical pressure above 40 mm Hg in the region adjacent to the wound surface. For example, the pressure sensitive activation region can be configured to activate the transmission unit in the presence of physical pressure above 50 mm Hg in the region adjacent to the wound surface.

Some embodiments of an appurtenance to a cavity wound dressing include: a substrate configured to fit substantially within a cavity wound in association with a primary wound dressing; and a plurality of sensor units attached to the substrate, each of the sensor units including a detector and an indicator, wherein the indicator includes a passive radio frequency identification (RFID) unit. For example, an indicator including a passive radio frequency identification (RFID) unit can be configured to alter the response of the passive RFID to an interrogation signal in response to the associated detector.

Some embodiments include a system for monitoring a cavity wound medical dressing, including: an appurtenance to a cavity wound dressing, the appurtenance including a substrate and a plurality of sensor units, wherein each of the sensor units include an indicator configured to respond to a specific external signal; and an external device configured to transmit the specific external signal and detect the response of the indicator included with each of the plurality of sensor units. For example, an

appurtenance can include a plurality of attached sensor units that include detectors that recognize a specific analyte by binding to that analyte. The sensor units also include indicators that respond to the analyte binding by the detector with a structural change in a chemical component of the indicator chemistry, wherein the structural changes result in an altered response to a signal transmitted by an external device. The indicators can include, for example, one or more RFID antennas and the external device include a radio frequency signal transmitter and receiver. The indicators can include, for example, a chemical compound configured to reflect some wavelengths of light differently in different conformations, and the external device include an emitter of the specific light wavelengths and a receiver for the reflections.

In some embodiments, an appurtenance is configured to provide an automatic notification of detection of a condition in a cavity wound. For example, a sensor unit attached to a battery and a LED light on the edge of the appurtenance can be configured to initiate the light turning on in response to a detected analyte. For example, a sensor unit attached to a battery and an active RFID unit can be configured to transmit a RFID signal in response to a condition, such as physical pressure above a preset maximum threshold in the wound cavity. In some embodiments, an automatic notification of detection of a condition in a cavity wound is a notification that is apparent by an observer externally to the wound dressing, without the use of additional devices. For example, an appurtenance can include a plurality of sensor units with detectors configured to respond to physical pressure above a preset threshold level, and indicators that include audible alarms in response to the detection. A caregiver and/or a cavity wound patient can hear the audible alarm in real-time, giving these individuals the opportunity to quickly intervene and reduce the physical pressure at the cavity wound site. An appurtenance can be removable with a wound dressing change and the attached sensor units subsequently interrogated, such as with a RFID transmitter and receiver device. In some embodiments, an appurtenance can be left in situ in a cavity wound during interrogation by an external device, such as a RFID transmitter and receiver.

The state of the art has progressed to the point where there is little distinction left between hardware, software, and/or firmware implementations of aspects of systems; the use of hardware, software, and/or firmware is generally (but not always, in that in certain contexts the choice between hardware and software can become significant) a design choice representing cost vs. efficiency tradeoffs. There are various vehicles by which processes and/or systems and/or other technologies described herein can be effected {e.g., hardware, software, and/or firmware), and that the preferred vehicle will vary with the context in which the processes and/or systems and/or other technologies are deployed. For example, if an implementer determines that speed and accuracy are paramount, the implementer can opt for a mainly hardware and/or firmware vehicle; alternatively, if flexibility is paramount, the implementer can opt for a mainly software implementation; or, yet again alternatively, the implementer can opt for some combination of hardware, software, and/or firmware. Hence, there are several possible vehicles by which the processes and/or devices and/or other technologies described herein can be effected, none of which is inherently superior to the other in that any vehicle to be utilized is a choice dependent upon the context in which the vehicle will be deployed and the specific concerns {e.g., speed, flexibility, or predictability) of the implementer, any of which can vary. Optical aspects of implementations will typically employ optically-oriented hardware, software, and or firmware.

In some implementations described herein, logic and similar implementations can include software or other control structures. Electronic circuitry, for example, can have one or more paths of electrical current constructed and arranged to implement various functions as described herein. In some implementations, one or more media can be configured to bear a device-detectable implementation when such media hold or transmit a device detectable instructions operable to perform as described herein. In some variants, for example, implementations can include an update or modification of existing software or firmware, or of gate arrays or programmable hardware, such as by performing a reception of or a transmission of one or more instructions in relation to one or more operations described herein. Alternatively or additionally, in some variants, an

implementation can include special-purpose hardware, software, firmware components, and/or general-purpose components executing or otherwise invoking special-purpose components. Specifications or other implementations can be transmitted by one or more instances of tangible transmission media as described herein, optionally by packet transmission or otherwise by passing through distributed media at various times.

Alternatively or additionally, implementations can include executing a special- purpose instruction sequence or invoking circuitry for enabling, triggering, coordinating, requesting, or otherwise causing one or more occurrences of virtually any functional operations described herein. In some variants, operational or other logical descriptions herein can be expressed as source code and compiled or otherwise invoked as an executable instruction sequence. In some contexts, for example, implementations can be provided, in whole or in part, by source code, such as C++, or other code sequences. In other implementations, source or other code implementation, using commercially available and/or techniques in the art, can be compiled/ /implemented/translated/converted into a high-level descriptor language (e.g., initially implementing described technologies in C or C++ programming language and thereafter converting the programming language implementation into a logic-synthesizable language implementation, a hardware description language implementation, a hardware design simulation implementation, and/or other such similar mode(s) of expression). For example, some or all of a logical expression (e.g., computer programming language implementation) can be manifested as a Verilog-type hardware description (e.g., via Hardware Description Language (HDL) and/or Very High Speed Integrated Circuit Hardware Descriptor Language (VHDL)) or other circuitry model which can then be used to create a physical implementation having hardware (e.g., an Application Specific Integrated Circuit). Those skilled in the art will recognize how to obtain, configure, and optimize suitable transmission or computational elements, material supplies, actuators, or other structures in light of these teachings.

The foregoing detailed description has set forth various embodiments of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples. Insofar as such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In one embodiment, several portions of the subject matter described herein can be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), digital signal processors (DSPs), or other integrated formats. However, some aspects of the embodiments disclosed herein, in whole or in part, can be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g. , as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and or firmware would be well within the skill of one of skill in the art in light of this disclosure. In addition, the mechanisms of the subject matter described herein are capable of being distributed as a program product in a variety of forms, and that an illustrative embodiment of the subject matter described herein applies regardless of the particular type of signal bearing medium used to actually carry out the distribution.

Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a hard disk drive, a Compact Disc (CD), a Digital Video Disk (DVD), a digital tape, a computer memory, etc.; and a transmission type medium such as a digital and/or an analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communications link, a wireless communication link (e.g., transmitter, receiver, transmission logic, reception logic, etc.), etc.).

In a general sense, the various embodiments described herein can be implemented, individually and/or collectively, by various types of electro-mechanical systems having a wide range of electrical components such as hardware, software, firmware, and/or virtually any combination thereof; and a wide range of components that can impart mechanical force or motion such as rigid bodies, spring or torsional bodies, hydraulics, electro-magnetically actuated devices, and/or virtually any combination thereof.

Consequently, as used herein "electro-mechanical system" includes, but is not limited to, electrical circuitry operably coupled with a transducer (e.g. , an actuator, a motor, a piezoelectric crystal, a Micro Electro Mechanical System (MEMS), etc.), electrical circuitry having at least one discrete electrical circuit, electrical circuitry having at least one integrated circuit, electrical circuitry having at least one application specific integrated circuit, electrical circuitry forming a general purpose computing device configured by a computer program (e.g., a general purpose computer configured by a computer program which at least partially carries out processes and/or devices described herein, or a microprocessor configured by a computer program which at least partially carries out processes and/or devices described herein), electrical circuitry forming a memory device (e.g., forms of memory (e.g., random access, flash, read only, etc.)), electrical circuitry forming a communications device (e.g., a modem, communications switch, optical- electrical equipment, etc.), and/or any non-electrical analog thereto, such as optical or other analogs. Examples of electro-mechanical systems include but are not limited to a variety of consumer electronics systems, medical devices, as well as other systems such as motorized transport systems, factory automation systems, security systems, and/or communication/computing systems. Electro-mechanical as used herein is not necessarily limited to a system that has both electrical and mechanical actuation except as context can dictate otherwise.

In a general sense, the various aspects described herein can be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, and/or any combination thereof and can be viewed as being composed of various types of "electrical circuitry." Consequently, as used herein "electrical circuitry" includes, but is not limited to, electrical circuitry having at least one discrete electrical circuit, electrical circuitry having at least one integrated circuit, electrical circuitry having at least one application specific integrated circuit, electrical circuitry forming a general purpose computing device configured by a computer program (e.g., a general purpose computer configured by a computer program which at least partially carries out processes and/or devices described herein, or a microprocessor configured by a computer program which at least partially carries out processes and/or devices described herein), electrical circuitry forming a memory device (e.g., forms of memory (e.g., random access, flash, read only, etc.)), and/or electrical circuitry forming a communications device (e.g., a modem, communications switch, optical-electrical equipment, etc.). The subject matter described herein can be implemented in an analog or digital fashion or some combination thereof.

At least a portion of the devices and/or processes described herein can be integrated into an image processing system. A typical image processing system generally includes one or more of a system unit housing, a video display device, memory such as volatile or non- volatile memory, processors such as microprocessors or digital signal processors, computational entities such as operating systems, drivers, applications programs, one or more interaction devices (e.g., a touch pad, a touch screen, an antenna, etc.), control systems including feedback loops and control motors (e.g., feedback for sensing lens position and/or velocity; control motors for moving/distorting lenses to give desired focuses). An image processing system can be implemented utilizing suitable commercially available components, such as those typically found in digital still systems and/or digital motion systems.

At least a portion of the devices and/or processes described herein can be integrated into a data processing system. A data processing system generally includes one or more of a system unit housing, a video display device, memory such as volatile or non- volatile memory, processors such as microprocessors or digital signal processors, computational entities such as operating systems, drivers, graphical user interfaces, and applications programs, one or more interaction devices (e.g., a touch pad, a touch screen, an antenna, etc.), and/or control systems including feedback loops and control motors (e.g., feedback for sensing position and/or velocity; control motors for moving and/or adjusting components and/or quantities). A data processing system can be implemented utilizing suitable commercially available components, such as those typically found in data computing/communication and/or network computing/communication systems.

The herein described components (e.g., operations), devices, objects, and the discussion accompanying them are used as examples for the sake of conceptual clarity and that various configuration modifications are contemplated. Consequently, as used herein, the specific examples set forth and the accompanying discussion are intended to be representative of their more general classes. In general, use of any specific example is intended to be representative of its class, and the non-inclusion of specific components (e.g., operations), devices, and objects should not be taken limiting.

The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected," or "operably coupled," to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable," to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components, and/or wirelessly interactable, and/or wirelessly interacting components, and/or logically interacting, and/or logically interactable components.

With respect to the use of substantially any plural and/or singular terms herein, the plural can be translated to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations are not expressly set forth herein for sake of clarity.

In some instances, one or more components can be referred to herein as

"configured to," "configured by," "configurable to," "operable/operative to,"

"adapted/adaptable," "able to," "conformable/conformed to," etc. Those skilled in the art will recognize that such terms (e.g. "configured to") can generally encompass active-state components and/or inactive-state components and/or standby-state components, unless context requires otherwise.

While particular aspects of the present subject matter described herein have been shown and described, changes and modifications can be made without departing from the subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of the subject matter described herein. Terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). If a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims can contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to claims containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two

recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., " a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., " a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.).

Typically a disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms unless context dictates otherwise. For example, the phrase "A or B" will be typically understood to include the possibilities of "A" or "B" or "A and B." With respect to the appended claims, the recited operations therein can generally be performed in any order. Also, although various operational flows are presented in a sequence(s), it should be understood that the various operations can be performed in other orders than those which are illustrated, or can be performed concurrently. Examples of such alternate orderings can include overlapping, interleaved, interrupted, reordered, incremental, preparatory, supplemental, simultaneous, reverse, or other variant orderings, unless context dictates otherwise. Furthermore, terms like "responsive to," "related to," or other past-tense adjectives are generally not intended to exclude such variants, unless context dictates otherwise.

EXAMPLES

Example 1. An Appurtenance to a Wound Dressing Configured to Detect and Report Fluid in a Wound Dressing.

An appurtenance to a wound dressing is constructed from a flexible thin plastic substrate that is configured in a substantially planar shape. A passive RFID antenna is attached to a surface of the substrate with epoxy. Circuitry for the RFID is attached to the substrate with adhesive and connected to the antenna with conductive ink (e.g., polymer with flecks of silver) as needed to create an operational RFID. Also a port for a polyester tube with approximately 0.5 mm inside diameter is mounted in contact with the antenna with epoxy (see Fig. 12). The polyester tube projects away from the surface of the substrate for approximately 4 millimeters (mm). Encapsulating epoxy material is used to cover the RFID circuit, the conductive ink, conductive epoxy and exterior of the tube port. A space is maintained around the edge of the polyester tube adjacent to the antenna under the encapsulating epoxy material. The space is configured to allow fluid to flow from the tube into contact with the surface of the antenna. The space is approximately 1 mm high and of sufficient lateral dimensions to cover a region of the antenna (e.g. 2-3 mm across). Methods and circuitry to construct passive RFID tags are described (see e.g., U.S. Patent No. 7,479,886 issued to Burr, titled "Antenna Capacitance for Energy Storage" and Chawla, "An Overview of Passive RFID," IEEE Applications & Practice, 11-17,

(September 2007), which are each incorporated herein by reference).

The substrate of the appurtenance is attached to the outer surface of a wound dressing with adhesive. A styrene copolymer pressure-sensitive adhesive can be used. In addition, the distal end of the polyester tube is pressed into the layers of the wound dressing with finger-tip pressure (see Figure 2B). The wound dressing is of sufficient thickness so as to maintain the end of the polyester tube within the layers of the wound dressing, allowing for both the length of the tube itself and the angle it projects from the substrate. For example, if the tube is 4 mm long, the wound dressing can be 6 mm thick, or greater. For example, if the tube is 4 mm long, the wound dressing can be 4 mm thick if the tube is placed at a sufficient angle to maintain the distal end of the tube within the wound dressing. The wound dressing with the appurtenance is placed immediately over the wound and the RFID identity number, patient information, the time and date are entered into a central computer system after interrogating the RFID tag with a RFID reader in a local unit and accessing the patient's electronic medical record. If the patient is wearing an RFID identification device (such as a wristband with an embedded RFID), the patient information can be input into the system by scanning the identification device in association with scanning the appurtenance.

A RFID reader in a local unit proximal to the patient (e.g., on the edge patient's hospital bed or on a bedside table) is used to periodically interrogate the appurtenance on the wound dressing by transmitting a signal in the UHF range (e.g. 902-928 MHz). The local unit can be set to interrogate the appurtenance on a regular schedule, for example every 5 minutes, every 10 minutes, or every half hour. The local unit can also be set to interrogate the appurtenance on command by a user, such as a nurse, orderly, or other caregiver. The appurtenance receives the incident UHF waves and harvests energy to activate the RFID circuitry and transmit a backscatter signal to the RFID reader. The signal encodes the identity of the RFID device and the signal reflects the status of the antenna. If moisture present in the wound dressing reaches levels sufficient for fluid to flow from the wound dressing into the tube of the appurtenance and into contact with the RFID antenna of the appurtenance (e.g. as illustrated in Figure 13), contact with the fluid on the antenna will modulate function of the antenna. This modulation, which can be a complete loss of function or a reduction or alteration of the "dry" signal, provides a notice to the system that the wound dressing should be checked by a medical caregiver. Excess moisture to the level of fluid flow into the appurtenance can be caused, by example, from the patient bleeding at the wound site, or excess wound exudates.

The RFID reader in the local unit receives signals from the appurtenance RFID device and transmits signals to a central computer that convey: the patient identity, time, date, and moisture status of the wound dressing. The central computer can notify caregivers, for example through a message sent to the nursing station, if the antenna signal from the appurtenance is modulated in a subsequent query, or series of queries. The local unit can also indicate to a healthcare worker the need to change a wound dressing based on the elapsed time since the wound dressing was applied (i.e. when the appurtenance was first "read" into the system).

Example 2. An Appurtenance to a Wound Dressing Configured to Detect and Report Fluid Directly from the Wound or Wound Bed.

An appurtenance to a wound dressing is constructed substantially similarly as described in Example 1, above. However, the wound dressing is of sufficient thickness so as to allow the end of the polyester tube to protrude through the layers of the wound dressing, allowing for both the length of the tube itself and the angle it projects from the substrate. For example, if the tube is 6 mm long, the wound dressing can be 4 mm thick, depending on the angle of the tube projection through the wound dressing. For example, if the tube is 4 mm long, the wound dressing can be 4 mm thick if the tube is placed at a sufficient angle to allow the distal end of the tube to be at the surface of, or protrude from, the wound dressing. The polyester tube should not protrude from the wound dressing in a manner to create a new injury or puncture in the wound or body part. In contrast, if a wound contains a region that is a hollow or depression relative to the adjacent body part surface, the polyester tube can be positioned with its terminal region within this hollow or depression. The appurtenance and affixed wound dressing can then be monitored substantially similarly as described in Example 1, above. Example 3. An Appurtenance Inserted into a Wound Dressing to Monitor Wound

Healing and Infection is Constructed Using a Passive RFID Tag and Sensors Inside an Enclosure of a Height and Width to Fit Substantially Within the Wound Dressing.

An appurtenance for a wound dressing configured to monitor wound healing and infection is constructed with an enclosure structure (as illustrated in Figs. 5A, 5B, 6 and 7). The appurtenance to a wound dressing includes a programmable RFID sensor device. The device is constructed with a RFID device on a printed circuit board with external sensors. For example, the device can contain a dipole antenna of 22-gauge copper magnet wire, a rectifier to convert incoming UHF energy into DC, a capacitor to store the energy, and a programmable microcontroller to perform sensing and computation (see e.g., Sample et al., "Design of an RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). The RFID device can also include multiple sensors connected to the microcontroller to detect wound healing and infection. Each sensor is in fluid communication with the lower portion of the appurtenance relative to the insertion point into the wound dressing. The sensors are located substantially within the enclosure and adjacent to an opening in the enclosure {see, e.g. Fig. 6). For example, a moisture sensor comprised of two electrodes located adjacent to an opening in the enclosure can be used to monitor the amount of fluids {e.g., exudate and blood) inside the wound dressing emanating from the wound. The electrode-based moisture sensor correlates moisture levels and impedance in the sensor (see e.g., McColl et al, "Monitoring Moisture without Disturbing the Wound Dressing," Wounds UK 5: 94-99, 2009 which is incorporated herein by reference). Wound moisture levels are correlated with healing, and a rapid increase in moisture level can indicate a microbial infection is present (see e.g., U.S. Patent No. 6,963,772 to Bloom et al. titled "User-Retainable Temperature and Impedance Monitoring Methods and

Devices," which is incorporated herein by reference). The RFID device includes a second sensor configured to measure the temperature of the wound dressing, and by extension the adjacent wound region. For example, an external analog temperature sensor can be connected to the microcontroller of the device and extend into the wound dressing to monitor the temperature of the wound dressing and adjacent wound region. RFID devices with external temperature sensors accurate to approximately 2° C are described (see e.g., Sample et al., "Design of an RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). Methods to use temperature sensors to detect the presence of microbial infections are known. For example, a thermistor-based sensor is used to monitor the temperature of a wound and indicate the presence of an infection or normal wound healing (see e.g., U.S. Patent No. 6,963,772 to Bloom et al. titled "User-Retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference).

The appurtenance to a wound dressing is constructed in a "thumb tack" or "rivet" shaped design (as illustrated in Figs. 5A, 5B, 6 and 7). The device enclosure is approximately 1-2 cm in diameter at the top and includes a region approximately 5 mm long that extends into the wound dressing. The enclosure contains the thermistor-based temperature sensor which is exposed to the wound surface and the moisture sensor, both positioned adjacent to an opening in the enclosure. See Fig. 6. In addition, the appurtenance is constructed with a pressure-sensitive adhesive on the underside of the flange at the top and barbs on the projection to hold the attachment firmly in place after insertion in the bandage (see Fig. 6). Methods and materials to construct RFID tags and housings are described (see e.g., U.S. Patent No. 6,693,513 to Turtle, titled "Wireless Identification device, RFID Device with Push-On/Push Off Switch, and Method of Manufacturing Wireless Identification Device" and Sample et al., "Design of an RFID- Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608- 2615, 2008 which are each incorporated herein by reference).

The wound dressing appurtenance is used to monitor healing and infection of an individual's wound and to signal healthcare workers when the wound and the wound dressing need attention. The appurtenance is inserted manually in the wound dressing, and the combination unit is placed immediately over the wound to position the moisture and temperature sensors in the wound dressing proximal to the wound. The attachment receives UHF waves {e.g., approximately at 902-928 MHz) from a RFID reader in a local unit that is installed near the patient {e.g., within 10-15 meters for optimal signal from UHF waves), for example on the bed or on the wall of the hospital room. The RFID device receives UHF waves transmitted from the reader via the antenna, power harvesting circuitry, rectifying circuitry and a capacitor to empower the RFID device with direct (DC) current at approximately 1.8 volts. The power is used to drive the microcontroller which energizes the sensors, collects and computes data from the sensors and transmits a unique identification code and the collected sensor data to the RFID reader; the time and date of the signal transmission are also encoded and sent to the RFID reader. The local unit including the RFID reader includes circuitry and processors to transmit the data to a central computer where it is entered into an electronic medical record for the patient and also sent to a healthcare worker assigned to the patient or the room.

Patient information, the bandage attachment ID code and the program for signal transmission from the local unit are entered in the central computer system and verified when the bandage appurtenance is installed by an initial signal transmission from the local unit. For example, a bandage appurtenance with a designated ID number is assigned to a patient by entering the ID number into the patient's electronic medical record when the appurtenance is inserted in the patient's wound dressing. The healthcare worker can use a mobile computer, e.g., laptop computer, to enter the ID number, the type of wound, type of bandage and the interrogation schedule for the local unit. The patient information and the ID code are verified by an initial interrogation by the RFID reader within the local unit.

Example 4: A Bandage Appurtenance System is Used to Monitor Wound

Dressings on a Patient with Recurrent Bacterial Infections.

A patient with a history of methicillin resistant Staphylococcus aureus (MRSA) infections is treated for a leg wound with a wound dressing and an appurtenance system that monitors the wound dressing for signs of infection and sends a signal when the wound dressing may need attention from a caregiver. The appurtenance to the wound dressing system reports data on the status of the wound dressing locally (within 10 meters of the patient) to a local unit containing a RFID reader. The local unit then processes the incoming signal and transmits information over an intranet or the internet to a central computer assembly. The appurtenance to the wound dressing system includes: an appurtenance to the wound dressing, which is a RFID sensor device; a local unit including a RFID reader which interrogates the attachment with UHF waves and receives and transmits data; and a central computer assembly which stores the data and transmits an alert for health caregivers in response to the information transmitted by the local unit.

An appurtenance to the wound dressing is constructed including a RFID device that contains a microcontroller and multiple sensors (see Figs. 10A, 10B, 11A and 1 IB). Each of the sensors is substantially enclosed within a projection which extends into the wound dressing when the appurtenance is in use. The RFID device is constructed on a printed circuit board with external sensors. For example, the device can contain a dipole antenna of 22-gauge copper magnet wire, a rectifier to convert incoming UHF energy into DC, a capacitor to store the current, and a programmable microcontroller {e.g., a

MSP430™ microcontroller available from Texas Instruments, Dallas, TX) to perform sensing and computation (see e.g., Sample et al., "Design of an RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). The RFID device has ports on the microcontroller to connect multiple sensors to detect wound healing and infection. The appurtenance receives UHF waves {e.g., approximately at 902-928 MHz) from a local unit containing a RFID reader that is installed near the patient {e.g., within 10-15 meters for UHF waves). A long range RFID reader operating in the UHF band with an input/output interface for the internet or the local area network is available from GAO RFID Inc., Seattle, WA. The RFID device in the appurtenance receives UHF waves transmitted from the reader integrated into the local unit via the appurtenance antenna, power harvesting circuitry, rectifying circuitry and capacitor. The incoming UHF signal empowers the RFID device of the appurtenance with DC current at approximately 1.8 volts. The power is used to drive the microcontroller which energizes the sensors, collects and processes data from the sensors and makes a transmission. The appurtenance transmits a unique identification code with the collected sensor data to the RFID reader in the local unit; the time and date of the signal transmission are also encoded and sent to the RFID reader.

Sensors which detect moisture, temperature and Staphylococcus aureus proteins are placed inside hollow tubes which project from the bottom of the bandage appurtenance into the wound dressing (see Figs. 10A, 10B, 11A and 1 IB). Tubes approximately 2-4 mm long, and approximately 5 mm in diameter project from the appurtenance. These projections contain the sensors and determine their effective penetration into the wound dressing. For example, a moisture sensor comprised of two electrodes which extend into the wound dressing through a projection can be used to monitor the amount of fluids {e.g., exudate and blood) emanating from the wound. Electrode -based moisture sensors are used to correlate wound moisture levels and impedance in the sensor (see e.g., McColl et al, "Monitoring Moisture without Disturbing the Wound Dressing," Wounds UK 5: 94-99, 2009 which is incorporated herein by reference) while wound moisture levels are correlated with healing. For example, a rapid increase in moisture level can indicate a microbial infection is present (see e.g., U.S. Patent No. 6,963,772 to Bloom et al. titled "User-Retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference). A second projection tube contains a thermistor-based temperature sensor which projects to a region adjacent to the wound surface. For example, an external analog temperature sensor can be connected to the microcontroller of the device and extend into the wound dressing to monitor the temperature of the wound. The approximate distance between the wound surface and the interior of the wound dressing can be taken into account when estimating temperature of the actual wound. RFID devices with external temperature sensors accurate to approximately 2° C are described (see e.g., Sample et al., "Design of an RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). Methods to use temperature sensors to detect the presence of microbial infections are known. For example, a thermistor-based sensor is used to monitor the temperature of a wound and indicate the presence of an infection or normal wound healing (see e.g., U.S. Patent No. 6,963,772 to Bloom et al. titled "User-Retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference). An average temperature taken over time, or a graph showing temperature readings over time can be presented to a system user by the central assembly computing system.

To specifically detect S. aureus in the wound, a third sensor is connected to the microcontroller and inserted in a tube projecting into the wound dressing. A nano- cantilever device that signals electronically when it binds a S. aureus antigen is constructed using a carbon nanotube and a monoclonal antibody {see e.g., U.S. Patent No. 7,612,424 to Espinosa and Ke titled "Nanoelectromechanical Bistable Cantilever Device," which is incorporated herein by reference). The nano-cantilever is functionalized with a monoclonal antibody specific for poly-N-acetylglucosamine (PNAG), a S. aureus antigen (see Kelly-Quintos et al., "Characterization of the Opsonic and Protective Activity Against Staphylococcus aureus of Fully Human Monoclonal Antibodies Specific for the Bacterial Surface Polysaccharide Poly-N-Acetylglucosamine" Infection and Immunity 74: 2742- 2750 (2006) which is incorporated herein by reference). Signals from the nano-cantilever, moisture sensor and temperature sensor are received by the microcontroller and transmitted to the local unit via the integrated RFID reader.

The local unit transmits signals received from the appurtenance to the wound dressing to a central computer assembly that stores the data and alerts hospital caregivers if an infection is detected or the wound dressing needs attention. For example, if the patient's bandage appurtenance is interrogated by the RFID reader and the S. aureus sensor {i.e. nano-cantilever) signals that S. aureus antigen is detected in the wound dressing, the local unit including the RFID reader transmits the information to the central computer assembly that issues an alert {e.g., email) to the nurses and/or doctors attending to the patient. Moreover, the wound dressing data is stored in the patient's electronic health record. The local unit also has programs and circuitry to interrogate the bandage appurtenance according to a predetermined schedule and report back to the central computer assembly. The wound dressing appurtenance system interacts with healthcare personnel through the central computer assembly and records and stores information on the wound dressing, changes in the wound dressing, infections and wound healing. An individual user can query the system for information, and the system can be preset to report at a particular time (e.g. the start of the day, or the start of a medical work shift). Example 5: An Individual with 2ⁿ Degree Burns on their Leg is Treated with

Wound Dressings and a Wound Dressing Monitor System to Monitor the Moisture Level and Infection Status of the Burn Wounds.

An individual has suffered 2^nd degree burn wounds that cover approximately 200 cm² of the leg. Medical personnel have chosen an absorbent wound dressing which removes excess exudates but retains moisture in the wound. For example, an

antimicrobial wound dressing (e.g., Mepilex® Ag available from Molnlycke Health Care US, LLC, Norcross, GA) is applied as an inner layer over the wound and a gauze dressing is applied as an absorbent outer layer to hold the inner layer dressing in place. To monitor the wound dressing, three bandage appurtenances are inserted approximately every 5 cm over the length of the wound site to monitor different areas of the burn wound. Each wound dressing appurtenance has a unique RFID identifier, a microcontroller, a moisture sensor and bacterial sensors. The placement and identification information for each appurtenance and the patient is read into the system with a local unit including an RFID reader at the time the wound dressing is placed on the patient's leg wound.

Each disposable wound dressing appurtenance includes a RFID device and a sensor with a microcontroller to direct sensing in the wound dressing. The system also includes a local unit configured to interrogate the wound dressing appurtenances and to communicate information to a central computer assembly for the wound monitoring system. A UHF RFID sensor device with a microcontroller and external sensors (see e.g., Sample et al., "Design of an RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference) is constructed with a plastic housing and projections which extend from the surface of the appurtenance into the wound dressing (see Figs. 10A, 10B, 11A and 1 IB). A projection contains a moisture sensor. For example, a moisture sensor comprised of two electrodes which project into the wound dressing to reach the wound surface can be used to monitor the amount of fluids (e.g., exudate and blood) emanating from the wound. Electrode- based moisture sensors are used to correlate wound moisture levels and impedance in the sensor (see e.g., McColl et al, "Monitoring Moisture without Disturbing the Wound Dressing," Wounds UK 5: 94-99, 2009 which is incorporated herein by reference) and wound moisture levels are correlated with healing. For example, a rapid increase in moisture level can indicate a microbial infection is present (see e.g., U.S. Patent No.

6,963,772 to Bloom et al. titled "User-Retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference). Bacterial sensors to detect proteins specific to Staphylococcus aureus and Pseudomonas aeruginosa, pathogens which frequently infect burn wounds, are constructed within projections configured to extend into the wound dressing from the appurtenance surface. Information from these sensors is transmitted to the microcontroller. For example, a nano-cantilever device that signals electronically when it binds a S. aureus antigen is constructed using a carbon nanotube (see e.g., U.S. Patent No. 7,612,424 to Espinosa and Ke titled

"Nano electromechanical Bistable Cantilever Device," which is incorporated herein by reference). The nano-cantilever is functionalized with a monoclonal antibody specific for poly-N-acetylglucosamine (PNAG), a S. aureus antigen (see Kelly-Quintos et al, "Characterization of the Opsonic and Protective Activity Against Staphylococcus aureus of Fully Human Monoclonal Antibodies Specific for the Bacterial Surface Polysaccharide Poly-N-Acetylglucosamine" Infection and Immunity 74: 2742-2750 (2006) which is incorporated herein by reference). An equivalent nano-cantilever device to detect P. aeruginosa is constructed with a specific anti- . aeruginosa monoclonal antibody

(available from Abeam, San Francisco, CA). The bacterial sensors can project in different tubes or the same projection tube. When the sensors encounter bacterial antigens, a signal is transmitted to the microcontroller. A corresponding signal is then transmitted from the appurtenance to the local unit in response to a query signal from the local unit.

One part of the wound dressing becomes saturated with fluid exudates after 16 hours and the proximal moisture sensor in the appurtenance attached to that region of the wound dressing signals the local unit (programmed to interrogate the appurtenance every 4 hours) that the dressing is saturated. The local unit signals that a dressing needs attention with an LED light on the local unit and also sends a signal with information regarding the RFID identity, patient ID and moisture sensor data to a central computer assembly. The central computer assembly is configured to alert hospital personnel. The information is also automatically entered into the patient's electronic medical record by the central computer assembly. A nurse responds to the central computer assembly alert that has been sent to the nursing station. The nurse physically inspects the wound dressing identified by the alert information. The saturated portion of the wound dressing is removed and disposed of, with the appurtenance still attached. The wound dressing is replaced and a new dressing appurtenance with a new RFID number and the patient's ID is inserted in the new wound dressing.

Example 6: Wound Dressing Appurtenance Used to Monitor a Wound Dressing on an Individual with a Venous Leg Ulcer.

An individual with a chronic wound, a venous leg ulcer, is treated in the patient's home with a wound dressing and a wound dressing appurtenance system to monitor the wound dressing and indicate when the dressing needs attention. Information regarding a series of wound dressings over time is also automatically saved into the patient's medical record for reference by medical personnel. The appurtenance system includes: a wound dressing appurtenance with a RFID sensor; a local unit with a RFID reader and a central computer assembly associated with the patient's clinic or hospital.

The patient's leg ulcer is treated in the patient's home in accordance with instructions from a medical caregiver, such as a nurse, who chooses a wound dressing including absorbent padding and a short stretch bandage (available from Activa

Healthcare). The appurtenance is inserted into the dressing over the wound with a projection penetrating into the wound dressing. The appurtenance is fixed securely in place with adhesive on the flange of the device and by virtue of barbs on the outside of the appurtenance that affix it securely to the wound dressing.

The disposable appurtenance includes a programmable RFID sensor device. The appurtenance is constructed with a RFID tag on a printed circuit board with external sensors. For example, the appurtenance can contain a dipole antenna of 22-gauge copper magnet wire, a rectifier to convert incoming UHF energy into DC voltage, a capacitor to store the voltage, and a programmable microcontroller to perform sensing and

computation (see e.g., Sample et al., "Design of an RFID-Based Battery-Free

Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). A moisture sensor comprised of two electrodes which project into the wound dressing can be used to monitor the amount of fluids (e.g., exudate and blood) emanating from the wound into the dressing. The electrode-based moisture sensor correlates moisture levels and impedance in the sensor (see e.g., McColl et al, Wounds UK 5: 94-99, 2009 which is incorporated herein by reference). Wound moisture levels are correlated with healing, and a rapid increase in moisture level, can indicate a microbial infection is present (see e.g., U.S. Patent No. 6963772 issued to Bloom et al. on Nov. 8, 2005 which is incorporated herein by reference).

The nurse installs the appurtenance system in the patient's home to allow remote monitoring of the leg ulcer. After manually pushing the appurtenance into the wound dressing, a local unit is used to query the appurtenance for its unique identification code and then to monitor the appurtenance. A local unit including a mobile RFID reader is installed in the patient's home. For example, a long range RFID reader operating in the UHF band with an input/output interface for the internet is available from GAO RFID Inc. The local unit transmits UHF waves (e.g., approximately at 902-928 MHz) from the bedside, a chair, or a table (e.g., within 10-15 meters of the wound dressing with the affixed appurtenance). The local unit is programmed by the nurse using a laptop computer to enter the RFID number, patient identification, and schedule for appurtenance interrogation (e.g., every 2 hours). The nurse also establishes a link between the local unit and a central computer assembly affiliated with the hospital or clinic. For example, a link to the patient's internet service is established to transmit data from the local unit to the central computer assembly. Information from the local unit can also be configured to automatically be included in the patient's electronic health record by the central computer assembly.

If the moisture sensor of the appurtenance detects excess moisture in the wound dressing, an alert is signaled to the patient and the hospital's central computer. The local unit receives a signal of excess moisture (i.e., low impedance) from the moisture sensor in the appurtenance and an LED on the local unit alerts the patient or a family member that the wound dressing needs attention. Also the local unit transmits the signal of excess moisture to the central computer assembly where an alert (e.g., an e-mail) is created for the nurses on duty.

The nurse receiving the alert can contact the patient and/or the patient can phone the nurse when the LED on the local unit lights up. The nurse can recommend the patient change the dressing or visit the patient to change the dressing and inspect the wound directly. The nurse, the patient or another caregiver can change the dressing and insert a new appurtenance in the dressing over the wound site. The new dressing appurtenance is verified by interrogating the new appurtenance with the local unit and the information is sent to the central computer assembly.

Example 7: An Appurtenance to a Wound Dressing Configured with a Fluid Activated Voltaic Cell to Detect and Report Fluid in a Wound Dressing in Real Time.

An appurtenance to a wound dressing is constructed from a flexible thin plastic substrate that is configured in a substantially planar shape (see Fig. 23). The appurtenance contains a transmission unit that includes: a microprocessor, memory, a transmitter, and an RFID antenna. The components are attached to a surface of the substrate with epoxy; and circuitry for the RFID are attached to the substrate with adhesive and connected to the antenna with conductive ink (e.g., polymer with flecks of silver) to create an operational RFID. A fluid activated voltaic cell is attached to the substrate and connected to the RFID with a wire connection. An aperture for a polyester tube with approximately 0.5 mm inside diameter is mounted in contact with the fluid activated voltaic cell (see Fig. 23) and attached to a polyester tube that projects away from the surface of the substrate for approximately 4 millimeters (mm). Encapsulating epoxy material is used to cover the components, the RFID circuitry, the conductive ink, conductive epoxy, the fluid activated voltaic cell and exterior of the tube port. A space is maintained around the edge of the polyester tube adjacent to the fluid activated voltaic cell under the encapsulating epoxy material. The space is configured to allow fluid to flow from the tube into contact with the fluid activated voltaic cell. The space is approximately 1 mm high and of sufficient lateral dimensions to cover the electrodes of the fluid activated voltaic cell (approximately 12 mm X 12 mm).

Methods and circuitry to construct passive RFID tags are described (see e.g., U.S. Patent No. 7,479,886 issued to Burr, "Antenna Capacitance for Energy Storage" and Chawla, "An Overview of Passive RFID," IEEE Applications & Practice, 11-17,

(September 2007), which are each incorporated herein by reference). For example, the device can contain a dipole antenna of 22-gauge copper magnet wire, a rectifier to convert incoming UHF energy into DC, a capacitor to store the energy, and a programmable microcontroller (e.g., a MSP430™ microcontroller available from Texas Instruments, Dallas, TX) to perform sensing and computation (see e.g., Sample et al, "Design of an

RFID-Based Battery-Free Programmable Sensing Platform," IEEE Trans. Instr. Meas. 57: 2608-2615, 2008 which is incorporated herein by reference). The RFID device can harvest energy from incoming radio waves or be empowered by current generated by the fluid activated voltaic cell.

A fluid activated voltaic cell serves as a moisture sensor and generates electrical current to empower the RFID device. A fluid activated voltaic cell is micro-fabricated from a silicon wafer with metallic layers serving as electrodes and wound fluids (e.g., exudate and blood) providing electrolyte to activate the voltaic cell. For example, a fluid activated voltaic cell can be constructed with magnesium, Mg, as the anode and silver chloride, AgCl, as the cathode (see e.g., Sammoura et al, Sensors and Actuators A 111: 79-86, 2004 and Lee et al., "Water Activated Disposable and Long Shelf Life

Microbatteries," Proceedings of IEEE Micro Electro Mechanical Systems Conference, pp. 387-390, Kyoto, Japan, Jan. 2003 which are incorporated herein by reference). A fluid activated voltaic cell is fabricated from silicon wafers by depositing a layer of Mg on a top substrate and AgCl on a bottom substrate and creating a gap of approximately 50 μιη between the Mg and AgCl layers using spacers. A layer of chromium/gold is deposited under the AgCl layer to collect electrons from the voltaic cell. A voltaic cell

approximately 12 mm x 12 mm produces a maximum output voltage of approximately 1.65 Volts with a voltaic cell capacity of approximately 1.8 mWatt-hours when the cell is activated with a drop of water, approximately 40 μί, and discharged under a resistance of 1 kilohm. This corresponds to reaching a maximum voltage of 1.6 V within a minute of activation and maintaining this level for approximately 20 minutes followed by a gradual decline to 0.6 V over the next 40 minutes. The output voltage of the fluid activated cell may be increased by providing enhancers that promote the electromotive force of the cell. For example, an enhancer of desiccated acid can be included in the electrochemical cell to produce acidic fluid and increase the voltage produced by the cell when fluid enters the cell (see e.g., Goodisman, "Observation on Lemon Cells", J. Chem. Ed. 78: 516-518, 2001 which is incorporated herein by reference). The provision of solid citric acid as an enhancer which dissolves upon contact with wound fluids can lower the pH of the fluid within the cell to approximately 3.0 and increase the electromotive force of the cell by increasing the dissolution of Mg (see e.g., Goodisman, Ibid.).

The substrate of the appurtenance is attached to the outer surface of a wound dressing with adhesive. A styrene copolymer pressure-sensitive adhesive can be used. In addition, the distal end of the polyester tube is pressed into the layers of the wound dressing with finger-tip pressure. The wound dressing is of sufficient thickness so as to maintain the end of the polyester tube within the layers of the wound dressing, allowing for both the length of the tube itself and the angle it projects from the substrate. For example, if the tube is 4 mm long, the wound dressing can be 6 mm thick, or greater. For example, if the tube is 4 mm long, the wound dressing can be 4 mm thick if the tube is placed at a sufficient angle to maintain the distal end of the tube within the wound dressing. The wound dressing with the appurtenance is placed immediately over the wound and the RFID identity number, patient information, the time and date are entered into a central computer system after interrogating the RFID tag with a RFID reader in a local unit and accessing the patient's electronic medical record. If the patient is wearing an RFID identification device (such as a wristband with an embedded RFID unit) the patient information can be input into the system by scanning the identification device in association with scanning the appurtenance.

The fluid activated voltaic cell is in fluid communication with the lower portion of the appurtenance relative to the insertion point into the wound dressing. For example, the voltaic cell is located adjacent to an opening in the enclosure and is used to monitor the amount of fluids that emanate from the wound and flow through the projection tube by capillary action. Wound moisture levels are correlated with healing, and a rapid increase in moisture level can indicate a microbial infection is present (see e.g., U.S. Patent No. 6,963,772 to Bloom et al., "User-Retainable Temperature and Impedance Monitoring Methods and Devices," which is incorporated herein by reference). Wound fluid entering the aperture activates the fluid activated voltaic cell which can yield approximately 1.8 mW-hours power (see e.g., Sammoura et al, Ibid.) to empower the RFID device which can operate with approximately 600 μW of power (see e.g., Sample et al, Ibid.). The empowered RFID device transmits a UHF signal which is received by a local unit proximal to the patient.

A RFID reader in a local unit (for example, a cell phone) proximal to the patient (e.g., on the edge of the patient's hospital bed or on a bedside table) receives the UHF signal from the RFID device. The UHF signal encodes information such as the patient's identity, the patient's room number, the identification number and location of the appurtenance, and the day and time of the signal transmission. The local unit responds by transmitting signals at the bedside to alert the patient and to a central computer to notify healthcare personnel. For example the local unit can signal at the bedside by emitting an audible alarm, and transmit wirelessly to a central computer which can notify caregivers, for example, through a message sent to the nursing station. The local unit can also indicate to a healthcare worker the need to change a wound dressing based on the elapsed time since the wound dressing was applied (i.e. when the appurtenance was first "read" into the system). Moreover the local unit transmission to a central computer creates a record in the patient's electronic health record which includes all of the information transmitted by the local unit relating to that appurtenance and any other appurtenances utilized by the same patient over time.

Embodiments include those wherein an appurtenance to a wound dressing includes: a substrate configured to mechanically or chemically attach to a wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; and a projection operably attached to the transmission unit, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid associated with a wound.

Embodiments include those wherein the substrate includes a substantially planar structure with a largest surface having a smaller square area than a largest surface of the wound dressing. Embodiments include those wherein the substrate includes an adhesive on a surface conforming to an external surface of the wound dressing. Embodiments include those wherein the substrate includes a flexible material. Embodiments include those wherein the substrate is configured to irreversibly attach to an external surface of the wound dressing.

Embodiments include those wherein the transmission unit is configured to transmit the signal in response to an interrogation signal. Embodiments include those wherein the transmission unit includes: a transmitter unit; and a receiver. Embodiments include those wherein the transmission unit includes a radio frequency identification (RFID) device. Embodiments include those wherein the transmission unit includes a radio frequency identification (RFID) device that is a passive radio frequency identification (RFID) device. Embodiments include those wherein the transmission unit includes a radio frequency identification (RFID) device that is an active radio frequency identification (RFID) device. Embodiments include those wherein the transmission unit includes at least two antennas. Embodiments include those wherein the transmission unit includes a Near Field

Communication (NFC) device. Embodiments include those wherein the transmission unit includes a self-compensating antenna system. Embodiments include those wherein the transmission unit includes non- volatile memory. Embodiments include those wherein the transmission unit includes a processor. Embodiments include those wherein the transmission unit includes a battery. Embodiments include those wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region includes a switch configured to be activated by physical pressure between a surface of the substrate and a surface of the wound dressing. Embodiments include those wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region includes a switch configured to be activated by physical pressure on a surface of the appurtenance.

Embodiments include those wherein the projection includes a physical conduit configured for fluid flow from the interior region of the wound dressing to a location in contact with the transmission unit. Embodiments include those wherein the projection includes a physical conduit and the physical conduit is configured for fluid flow from the interior region of the wound dressing to a location in contact with the at least one antenna of the transmission unit. Embodiments include those wherein the projection includes a substantially hollow tubular structure. Embodiments include those wherein the projection is of a size and shape to project from the outer surface of the wound dressing to within layers of the wound dressing. Embodiments include those wherein the projection is of a size and shape to project underneath one or more superficial structures of the wound dressing when the wound dressing is in use. Embodiments include those wherein the projection is of a size and shape to project through a width of the wound dressing when the appurtenance is attached to the wound dressing. Embodiments include those wherein the projection is fabricated from a plastic material. Embodiments include those wherein the projection includes: one or more sensors; and at least one substantially hollow enclosure substantially encircling the one or more sensors, the at least one substantially hollow enclosure including one or more openings within the enclosure distal to an attachment to the substrate. Embodiments include those wherein the projection includes one or more sensors partially internal to the projection. Embodiments include those wherein the projection includes one or more sensors configured to actuate a switch in the transmission unit in response to a stimulus.

Embodiments include those wherein the appurtenance to a wound dressing includes a substantially planar cover, the cover including an adhesive on a surface conforming to a surface of the wound dressing, the substantially planar cover configured to cover at least a part of the projection. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors; and a connector between the transmission unit and the one or more sensors. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors; and a wire connecting the transmission unit and the one or more sensors. Embodiments include those wherein the appurtenance to a wound dressing includes a sensor configured to be responsive to a change in capacitance, the sensor operably connected to the transmission unit.

Embodiments include those wherein the appurtenance to a wound dressing includes an indicator operably attached to the transmission unit. Embodiments include those wherein the appurtenance to a wound dressing includes a battery. Embodiments include those wherein the appurtenance to a wound dressing includes a processor, and a transceiver. Embodiments include those wherein the appurtenance to a wound dressing includes a sterile wrapper. Embodiments include those wherein the appurtenance to a wound dressing has been substantially sterilized. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch operably connected to the transmission unit. Embodiments include those wherein the appurtenance to a wound dressing includes a binary switch operably connected to the transmission unit.

Some embodiments of an appurtenance to a wound dressing include: a substrate configured to attach to a wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry; a selectively actuatable switch operably connected to the transmission unit; a projection operably attached to the substrate, the projection of a size and shape to extend into an interior region of a wound dressing; and one or more sensors integral to the projection and operably connected to the selectively actuatable switch.

Embodiments include those wherein the appurtenance to a wound dressing includes a substrate, wherein the substrate is a substantially planar structure with a largest surface area having a smaller square area than a largest surface area of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a substrate, wherein the substrate includes an adhesive on a surface conforming to an external surface of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a substrate, wherein the substrate includes a flexible material. Embodiments include those wherein the appurtenance to a wound dressing includes a substrate, wherein the substrate includes at least one bio-compatible material.

Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a transmitter unit and a receiver. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, wherein the transmission unit is configured to transmit a signal including information identifying the appurtenance. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, wherein the transmission unit is configured to transmit a signal in response to an interrogation signal. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a radio frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a passive radio frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including an active radio frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a Near Field Communication (NFC) device. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including non- volatile memory.

Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a processor. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, including a battery.

Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on at least part of the projection. Embodiments include those wherein the appurtenance to a wound dressing includes a transmission unit, wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure between a surface of the substrate and a surface of the wound dressing.

Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, including a connector between the transmission unit and the one or more sensors. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, including a physical conduit configured to allow a liquid to flow from the interior region of the wound dressing to a location in contact with the at least one antenna of the transmission unit. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, including a wire connecting the transmission unit and the one or more sensors. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, wherein the selectively actuatable switch is configured as a binary switch. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, wherein the selectively actuatable switch is configured to be irreversible. Embodiments include those wherein the appurtenance to a wound dressing includes a selectively actuatable switch, wherein the selectively actuatable switch is configured to be responsive to a change in capacitance.

Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection includes a substantially hollow tubular structure. Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection is of a size and shape to project within the interior region of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection is of a size and shape to project within layers of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection is of a size and shape to project through a width of the wound dressing.

Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection is of a size and shape to project underneath one or more superficial structures of the wound dressing when the wound dressing is in use.

Embodiments include those wherein the appurtenance to a wound dressing includes a projection, wherein the projection is fabricated from a plastic material. Embodiments include those wherein the appurtenance to a wound dressing includes a projection, including at least one substantially hollow enclosure substantially encircling the one or more sensors, the at least one substantially hollow enclosure including one or more openings within the enclosure distal to an attachment to the substrate.

Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors integral to the projection, including one or more sensors partially internal to the projection. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors integral to the projection, including one or more sensors configured to actuate the selectively actuatable switch in response to a stimulus.

Embodiments include those wherein the appurtenance to a wound dressing includes a substantially planar cover, the cover including an adhesive on a surface conforming to a surface of the wound dressing, the substantially planar cover configured to cover a location where the projection extends into the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an indicator operably attached to the selectively actuatable switch. Embodiments include those wherein the appurtenance to a wound dressing includes a battery. Embodiments include those wherein the appurtenance to a wound dressing includes a processor, and a transceiver. Embodiments include those wherein the appurtenance to a wound dressing includes a sterile wrapper. Embodiments include those wherein the appurtenance to a wound dressing has been substantially sterilized.

In some embodiments, an appurtenance to a wound dressing includes: one or more sensors; a processor operably attached to the one or more sensors; at least one transmitter unit operably attached to the processor; and an enclosure of a height and width to fit substantially within an interior region of a wound dressing.

Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors, wherein the one or more sensors are positioned substantially within the enclosure. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors, wherein the one or more sensors and the processor are positioned substantially within the enclosure. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors, including at least one sensor responsive to changes in capacitance. Embodiments include those wherein the appurtenance to a wound dressing includes one or more sensors, wherein the processor is operably attached to the one or more sensors with one or more wire connections.

Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including a radio frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including an active radio frequency identification (RFID) device.

Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including a passive radio frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including an optical transmitter unit. Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including a transmitter unit of signals in the UHF range. Embodiments include those wherein the appurtenance to a wound dressing includes at least one transmitter unit operably attached to the processor, including a near field communication (NFC) device.

Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, wherein the enclosure is configured to substantially encircle the one or more sensors. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including a substantially cylindrical structure, wherein the largest width of the substantially cylindrical structure is less than the smallest width of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including a substantially pyramidal structure, wherein the largest width of the substantially pyramidal structure is less than the smallest width of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including a cross-section square area that is equal to or less than one tenth of a square area of a largest surface of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including one or more walls, the walls forming a fiange on an edge of the enclosure, the flange positioned to attach a fastener between a surface of the wound dressing and the enclosure. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including one or more walls, the walls forming a flange on an edge of the enclosure, the fiange including one or more projections from a surface of the flange, the one or more projections positioned to pierce an outer surface of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including one or more walls forming the enclosure; and one or more openings within the one or more walls, the openings forming a conduit between a region exterior to the enclosure and a region interior to the enclosure. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including at least one plastic material. Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including a substantially hollow tube. Embodiments include those wherein the appurtenance to a wound dressing includes a processor and at least one transmitter unit, including a radio-frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes a processor and at least one transmitter unit, including an active radio-frequency identification (RFID) device. Embodiments include those wherein the appurtenance to a wound dressing includes a processor and at least one transmitter unit, including a passive radio-frequency identification (RFID) device.

Embodiments include those wherein the appurtenance to a wound dressing includes an antenna, and a receiver operably attached to the antenna.

Embodiments include those wherein the appurtenance to a wound dressing includes a fastener configured to form a seal between an edge of the enclosure and a surface of the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a fastener, wherein the fastener includes a substantially planar cover with an upper surface and a lower surface, the lower surface conforming to both the edge of the enclosure and to the surface of the wound dressing, and adhesive on at least a portion of the lower surface of the substantially planar cover.

Embodiments include those wherein the appurtenance to a wound dressing includes an enclosure, including a flange region configured to cover part of an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a piercing region operably attached an edge of the enclosure distal to an edge of the enclosure adjacent to an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes a non-volatile memory unit operably attached to the processor. Embodiments include those wherein the appurtenance to a wound dressing includes a unique identifier for the appurtenance. Embodiments include those wherein the appurtenance to a wound dressing includes an energy storage unit.

Embodiments include those wherein the appurtenance to a wound dressing includes an indicator operably attached to the processor, the indicator positioned on a side of the appurtenance adjacent to an outer surface of the wound dressing when the appurtenance is positioned for use with the wound dressing. Embodiments include those wherein the appurtenance to a wound dressing includes an indicator operably attached to the processor, wherein the indicator is at least one of: a visual indicator, a vibratory indicator, or an auditory indicator.

In some embodiments, an appurtenance to a wound dressing includes: a sensor unit including one or more sensors, the sensors positioned substantially within an enclosure of a height and width to fit substantially within an interior region of a wound dressing; a transmission unit including a processor and at least one transmitter operably attached to the processor; and a connector between the sensor unit and the transmission unit, the connector configured to convey signals between the one or more sensors and the transmission unit.

In some embodiments, an appurtenance to a wound dressing includes a sensor unit, wherein the sensor unit is configured to be responsive to changes in circuitry capacitance. In some embodiments, an appurtenance to a wound dressing includes an enclosure, wherein the enclosure is fabricated from one or more flexible materials.

In some embodiments, an appurtenance to a wound dressing includes a

transmission unit, including: an antenna; and a receiver operably attached to the antenna. In some embodiments, an appurtenance to a wound dressing includes a transmission unit, including a substrate including at least one surface configured to conform to an exterior surface of a body. In some embodiments, an appurtenance to a wound dressing includes a transmission unit, including non-volatile memory.

In some embodiments, an appurtenance to a wound dressing includes a connector, including one or more wires. In some embodiments, an appurtenance to a wound dressing includes a connector, including a conduit configured to allow flow of liquid from the sensor unit into the transmission unit.

In some embodiments, an appurtenance to a wound dressing includes an indicator operably attached to the transmission unit. In some embodiments, an appurtenance to a wound dressing includes an indicator operably attached to the transmission unit, wherein the indicator is at least one of: a visual indicator, a vibratory indicator, or an auditory indicator.

Some embodiments include an appurtenance to a wound dressing, including: a substrate; a passive radio frequency identification (RFID) unit attached to the substrate; and a substantially hollow projection operably attached to the substrate, the projection including a first end and a second end, the first end of a size and shape to extend within a wound dressing, the second end extending into the passive radio frequency identification (RFID) unit.

Some embodiments include a device, including: a wound dressing; a transmission unit irreversibly attached to the wound dressing, the transmission unit including circuitry and at least one antenna; a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending within an interior region of the wound dressing.

Some embodiments include a wound dressing unit, including: a wound dressing; a substrate attached to an external surface of the wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending through the external surface of the wound dressing.

In some embodiments, a device for attaching an appurtenance to a wound dressing includes: a base plate; a handle attached to the base plate; a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing; a handle attached to the holder region; and a pivot between the handle attached to the base plate and the handle attached to the holder region.

In some embodiments, a device for attaching an appurtenance to a wound dressing includes a base plate, wherein the base plate includes: a substantially planar surface of a size and shape substantially corresponding to a substantially planar surface of the appurtenance; and a concavity within the substantially planar surface of the base plate, the concavity substantially corresponding to a height and a cross-section of the appurtenance. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a base plate and a handle attached to the base plate, wherein the handle attached to the base plate includes a handle of a size and shape configured for use by an adult human hand. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a base plate and a handle attached to the base plate, wherein the handle attached to the base plate includes a substantially linear handle attached at a less than 45 degree angle relative to the base plate.

In some embodiments, a device for attaching an appurtenance to a wound dressing includes a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing, wherein the holder region includes a flange of a size and shape to retain a region of the appurtenance to the wound dressing adjacent to a surface of the wound dressing during attachment. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing, wherein the holder region includes a clamp of a size and shape corresponding to a region of the appurtenance to the wound dressing. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing and a handle attached to the holder region, wherein the handle includes a handle of a size and shape configured for use by an adult human hand. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a holder region configured to hold an appurtenance to a wound dressing during attachment to a wound dressing and a handle attached to the holder region, wherein the handle includes a substantially linear handle attached at a less than 45 degree angle relative to the holder region. In some

embodiments, a device for attaching an appurtenance to a wound dressing includes a handle attached to the base plate and a handle attached to the holder region, wherein the handle attached to the base plate and the handle attached to the holder region are of a substantially similar size and shape. In some embodiments, a device for attaching an appurtenance to a wound dressing includes a pivot between the handle attached to the base plate and the handle attached to the holder region, including a rod traversing a cross- section of each of the handle attached to the base plate and the handle attached to the holder region when the respective handles are positioned adjacent to each other.

In some embodiments, a method of attaching an appurtenance to a wound dressing includes: placing an appurtenance to a wound dressing in contact with an outer surface of the wound dressing; and providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing.

In some embodiments, a method of attaching an appurtenance to a wound dressing includes placing an appurtenance to a wound dressing in contact with an outer surface of the wound dressing, wherein the placing an appurtenance for a wound dressing in contact with an outer surface of the wound dressing includes: removing an external cover of the wound dressing; and placing the appurtenance in contact with a superficial surface of the wound dressing. In some embodiments, a method of attaching an appurtenance to a wound dressing includes providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing, wherein the providing pressure on the appurtenance includes providing manual pressure. In some embodiments, a method of attaching an appurtenance to a wound dressing includes providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing, wherein the providing pressure on the appurtenance includes providing pressure in a direction substantially perpendicular to the outer surface of the wound dressing. In some embodiments, a method of attaching an appurtenance to a wound dressing includes providing pressure on the appurtenance sufficient to force a section of the appurtenance through the outer surface of the wound dressing and into an interior region of the wound dressing, wherein the providing pressure on the appurtenance includes providing pressure in a direction substantially at an angle to the outer surface of the wound dressing.

In some embodiments, a method of attaching an appurtenance to a wound dressing includes removing an external cover of the wound dressing from the outer surface of the wound dressing prior to placing the appurtenance in contact with the outer surface of the wound dressing. In some embodiments, a method of attaching an appurtenance to a wound dressing includes sealing a region including an edge of the appurtenance and an area of the wound dressing adjacent to the edge of the appurtenance with a cover. In some embodiments, a method of attaching an appurtenance to a wound dressing includes sealing a region including an edge of the appurtenance and an area of the wound dressing adjacent to the edge of the appurtenance by forcing one or more projections on the edge of the appurtenance into the outer surface of the wound dressing.

Some embodiments include an appurtenance to a wound dressing, including: a substrate configured to attach to a wound dressing; a fluid-activated voltaic cell attached to the substrate; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell; and a projection operably attached to the fluid-activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing. In some embodiments, the appurtenance includes: a second fluid-activated voltaic cell attached to the substrate and configured to activate the transmission unit; and a second projection operably attached to the second fluid-activated voltaic cell, the second projection configured to sample a second fluid within a second interior region of the wound dressing. In some embodiments, the appurtenance includes a sensor connected to the transmission unit.

In some embodiments, an appurtenance to a wound dressing includes a substrate configured to attach to a wound dressing, wherein the substrate is configured to chemically attach to the wound dressing. In some embodiments, an appurtenance to a wound dressing includes a substrate configured to attach to a wound dressing, wherein the substrate is configured to mechanically attach to the wound dressing. In some

embodiments, an appurtenance to a wound dressing includes a substrate configured to attach to a wound dressing, wherein the substrate is configured to integrate within the wound dressing. In some embodiments, an appurtenance to a wound dressing includes a substrate configured to attach to a wound dressing, wherein the substrate is configured to attach to an outer surface of the wound dressing.

In some embodiments, an appurtenance to a wound dressing includes a fluid- activated voltaic cell attached to a substrate, wherein the fluid-activated voltaic cell includes: at least one enhancement unit configured to release at least one chemical enhancer of an electrochemical reaction within the fiuid-activated voltaic cell in response to contact with the fluid. In some embodiments, an appurtenance to a wound dressing includes a fiuid-activated voltaic cell attached to a substrate, wherein the fiuid-activated voltaic cell includes at least one enhancement unit, wherein the at least one enhancement unit includes at least one dry acid unit configured to release an acid when contacted by a liquid.

In some embodiments, an appurtenance to a wound dressing includes a fluid- activated voltaic cell attached to a substrate, wherein the fluid-activated voltaic cell includes at least one desiccant unit within the fluid-activated voltaic cell. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to a substrate, wherein the fiuid-activated voltaic cell includes: at least one first electrode; and at least one second electrode. In some embodiments, an appurtenance to a wound dressing includes a fluid- activated voltaic cell attached to a substrate, wherein the fluid-activated voltaic cell includes at least one anode and at least one cathode. In some embodiments, an appurtenance to a wound dressing includes a fiuid-activated voltaic cell attached to a substrate, wherein the fluid-activated voltaic cell includes a chamber configured to receive the fluid.

In some embodiments, an appurtenance to a wound dressing includes a

transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid- activated voltaic cell, wherein the transmission unit includes a radio frequency identification (RFID) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, wherein the transmission unit includes a passive radio frequency identification (RFID) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the

transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, wherein the transmission unit includes an active radio frequency identification (RFID) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid- activated voltaic cell, wherein the transmission unit includes a near field communication (NFC) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, wherein the transmission unit includes a unique identifier. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, wherein the transmission unit includes non-volatile memory. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, wherein the transmission unit includes a processor. In some embodiments, an appurtenance to a wound dressing includes a projection operably attached to the fluid-activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing, wherein the projection includes: a plurality of apertures located along a length of the projection; and a plurality of conduits, each conduit including a first end attached to one of the plurality of apertures, and a second end attached to the fluid-activated voltaic cell, each conduit configured to direct the fluid from the interior region of the wound dressing into the fluid-activated voltaic cell. In some embodiments, an appurtenance to a wound dressing includes a projection operably attached to the fluid-activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing, wherein the projection is partially positioned within the fluid-activated voltaic cell, and wherein the projection includes an aperture within the fluid-activated voltaic cell.

In some embodiments, an appurtenance to a wound dressing includes a projection operably attached to the fluid-activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing, and a transmission unit attached to a surface of a substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell, including a wire connector between the fluid-activated voltaic cell and the transmission unit. In some embodiments, an appurtenance to a wound dressing includes a passive radio frequency identification (RFID) unit including an identifier.

Some embodiments include an appurtenance to a wound dressing, including: an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure; a fluid-activated voltaic cell attached to one or more of the at least one aperture; and a transmission unit attached to an internal surface of the enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid- activated voltaic cell. Some embodiments include a wire connector between the fluid- activated voltaic cell and the transmission unit. Some embodiments include a passive radio frequency identification (RFID) unit including an identifier. Some embodiments include a second fluid-activated voltaic cell attached to at least one second aperture, the at least one second aperture configured to allow a fluid to flow from a second interior region of the wound dressing into an interior of the second fluid-activated voltaic cell. Some embodiments include: a sensor attached to the at least one aperture of the enclosure; and a connection between the sensor and the transmission unit.

In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a substantially cylindrical structure, wherein a largest width of the substantially cylindrical structure is less than a smallest width of the wound dressing. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a substantially pyramidal structure, wherein a largest width of the substantially pyramidal structure is less than a smallest width of the wound dressing. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a cross-section square area that is equal to or less than approximately one tenth of a square area of a largest surface of the wound dressing. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes one or more walls, the walls forming a flange on an edge of the enclosure, the flange positioned to attach a fastener between a surface of the wound dressing and the enclosure. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes one or more walls, the walls forming a flange on an edge of the enclosure, the flange including one or more projections from a surface of the flange, the one or more projections positioned to pierce an outer surface of the wound dressing. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes at least one plastic material. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a substantially hollow tube. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a plurality of apertures.

In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a plurality of apertures, and at least one aperture of the enclosure includes a micro-capillary film configured to direct the fluid from the interior region of the wound dressing into an interior of the enclosure. In some embodiments, an appurtenance to a wound dressing includes an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure, wherein the enclosure includes a plurality of apertures, and at least one aperture of the enclosure includes a conduit configured to direct the fluid from the interior region of the wound dressing into an interior of the enclosure.

In some embodiments, an appurtenance to a wound dressing includes a fluid- activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid- activated voltaic cell includes at least one enhancement unit configured to release at least one chemical enhancer of an electrochemical reaction within the fluid-activated voltaic cell in response to contact with the fluid. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid-activated voltaic cell includes at least one enhancement unit, wherein the at least one enhancement unit includes: at least one dry acid unit configured to release acid when contacted by a liquid. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid-activated voltaic cell includes at least one desiccant unit within the fluid-activated voltaic cell. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid-activated voltaic cell includes at least one first electrode, and at least one second electrode. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid-activated voltaic cell includes at least one anode and at least one cathode. In some embodiments, an appurtenance to a wound dressing includes a fluid-activated voltaic cell attached to one or more aperture in the enclosure, wherein the fluid-activated voltaic cell includes a chamber configured to receive the fluid.

In some embodiments, an appurtenance to a wound dressing includes a

transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes a radio frequency identification (RFID) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes an active radio frequency identification (RFID) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes a passive radio frequency identification (RFID) unit. In some embodiments, an

appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes a near filed communication (NFC) unit. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes a unique identifier. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes non- volatile memory. In some embodiments, an appurtenance to a wound dressing includes a transmission unit attached to an internal surface of an enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to a fluid-activated voltaic cell, wherein the transmission unit includes a processor.

In some embodiments, an appurtenance to a wound dressing includes: an appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance; a fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit; and a radio frequency identification (RFID) unit attached to the fluid-activated voltaic cell and configured to operate in response to electrical power generated by the fluid-activated voltaic cell. In some embodiments, the appurtenance to a wound dressing includes: a wire connector between the fluid-activated voltaic cell and the radio frequency identification (RFID) unit. In some embodiments, the appurtenance to a wound dressing includes: a second conduit positioned to allow the fluid to flow from a second interior region of the wound dressing into the appurtenance; and a second fluid-activated voltaic cell including a second internal chamber, the second internal chamber attached to the second conduit, wherein the second fluid-activated voltaic cell is configured to direct current to the radio frequency identification (RFID) unit. In some embodiments, the appurtenance to a wound dressing includes: a sensor attached to the conduit; and a connector between the sensor and the radio frequency identification (RFID) unit.

Embodiments include those wherein the appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance, wherein the appurtenance is configured to attach to the interior region of the wound dressing.

Embodiments include those wherein the appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance, wherein the appurtenance is configured to integrate within the wound dressing. Embodiments include those wherein the appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance, wherein the appurtenance is configured to attach to an exterior surface of the wound dressing.

Embodiments include those wherein the conduit of the appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance, includes a plurality of microchannels configured to direct the fluid to flow into the fluid-activated voltaic cell. Embodiments include those wherein the conduit of the appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the

appurtenance, includes at least one projection, the projection including at least one aperture positioned distal to the appurtenance, the projection configured to allow the fluid to flow from the interior region of the wound dressing into the appurtenance.

Embodiments include those wherein the fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit, includes at least one enhancement unit configured to release at least one chemical enhancer of an

electrochemical reaction within the fluid-activated voltaic cell in response to contact with the fluid. In some embodiments, the at least one enhancement unit includes at least one dry acid unit configured to release an acid when contacted by a liquid. Embodiments include those wherein the fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit, includes at least one desiccant unit within the fluid-activated voltaic cell. Embodiments include those wherein the fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit, includes; at least one first electrode; and at least one second electrode. Embodiments include those wherein the fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit, includes at least one anode and at least one cathode. Embodiments include those wherein the fluid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit, includes a chamber attached to the conduit, the chamber configured to receive the fluid.

Embodiments include those wherein the radio frequency identification (RFID) unit attached to the fluid-activated voltaic cell and configured to operate in response to electrical power generated by the fluid-activated voltaic cell includes a unique identifier. Embodiments include those wherein the radio frequency identification (RFID) unit attached to the fluid-activated voltaic cell and configured to operate in response to electrical power generated by the fluid-activated voltaic cell includes an antenna, and circuitry configured to initiate a signal transmission from the antenna. Embodiments include those wherein the radio frequency identification (RFID) unit attached to the fluid- activated voltaic cell and configured to operate in response to electrical power generated by the fluid-activated voltaic cell includes a processor.

In some embodiments, a method of monitoring a wound includes: conveying fluid from an interior region of a wound dressing to an appurtenance of the wound dressing; placing the fluid adjacent to a first electrode and a second electrode of a fluid-activated voltaic cell integral to the appurtenance; and utilizing electrical power received from the fluid-activated voltaic cell directly to send a wireless signal beyond the appurtenance.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound; and a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a substantially planar, flexible structure. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a structure including the wound-facing surface of a size and shape to approximate the surface of the cavity wound, the structure no more than 15 mm in thickness relative to the at least one wound-facing surface. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a three dimensional structure with at least one wound-facing surface, the at least one wound- facing surface of a size and shape to reversibly mate with the wound surface of the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a substantially pliable and fluid-permeable structure. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a mesh structure. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a substantially flexible, fluid-permeable planar structure of no more than 5 mm in thickness. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes at least one cavity-facing surface of the substrate configured to be oriented facing the cavity region of the cavity wound, wherein the cavity-facing surface is positioned opposing the at least one wound-facing surface. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes a plurality of unidirectional fluid flow structures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound-facing surface to one or more of the plurality of sensor units attached to the substrate.

In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes a plurality of sensor units of at least two distinct types. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes a plurality of sensor units of at least two distinct types, and wherein the plurality of sensor units of at least two distinct types are oriented as a pattern relative to the wound surface. I In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one sensor unit configured to detect physical pressure, at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record an elapsed time value. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one sensor unit configured to detect one or more analytes of wound exudate. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes a plurality of sensor units of a size, shape, mass and arrangement so that the appurtenance is predicted to press with a force of less than 32 mm Hg at the wound surface during use with the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes a substrate including at least one wound-facing surface, the wound-facing surface configured to be oriented facing a wound surface of a cavity wound, wherein the substrate includes at least one antenna operably connected to at least one sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one chemical-based sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one fluid-activated sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one sensor unit configured to detect at least one analyte in wound exudate In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one sensor unit including an optically resolvable detection indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound, wherein the plurality of sensor units includes at least one sensor unit including a detection indicator operably connected to an RFID antenna.

In some embodiments, an appurtenance to a cavity wound dressing includes an appurtenance wherein the appurtenance is functional when in contact with an aqueous material. In some embodiments, an appurtenance to a cavity wound dressing includes at least one positional indicator. In some embodiments, an appurtenance to a cavity wound dressing includes at least one orientation indicator. In some embodiments, an

appurtenance to a cavity wound dressing includes an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound and at least one surface configured to be oriented facing a periwound region of the cavity wound; and at least one orientation indicator attached to the edge region. In some embodiments, an appurtenance to a cavity wound dressing includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound and at least one surface configured to be oriented facing a periwound region of the cavity wound; and at least one temperature sensor unit attached to the edge region. In some embodiments, an appurtenance to a cavity wound dressing includes: a wound dressing, the wound dressing configured to be positioned within the wound cavity, with the appurtenance between the wound dressing and the wound surface; and a second wound dressing, the second wound dressing configured to cover a wound region and stabilize the appurtenance and the wound dressing during use, the second wound dressing configured to be removable from the wound region after use. In some embodiments, an appurtenance to a cavity wound dressing includes: a detachable cover configured to reversibly mate with the substrate surface configured to be oriented facing a wound surface of a cavity wound.

In some embodiments, an appurtenance to a cavity wound dressing includes: a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fiuid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg; and the plurality of sensor units in the aggregate of a size and mass to allow for medical use with the porous dressing material at the cavity wound.

In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fiuid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: a plurality of sensor units including at least two distinct types of sensor units. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fiuid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units of at least two distinct types are oriented as a pattern relative to a surface of the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: a plurality of sensor units including at least one sensor unit configured to detect physical pressure, and at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record an elapsed time value. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: a plurality of sensor units including at least one sensor unit configured to detect one or more analytes from wound exudate. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: a plurality of sensor units of a size, shape, mass and arrangement predicted to create a force of less than 32 mm Hg at the wound surface during medical use with the porous dressing material. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one antenna operably attached to at least one sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one chemical-based sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one positional indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one temperature sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one pressure sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one fluid-activated sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one sensor unit including an optically resolvable detection indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a plurality of sensor units, wherein each sensor unit includes an attachment region configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees Centigrade, and under physical pressure up to 32 mm Hg, wherein the plurality of sensor units include: at least one sensor unit including a detection indicator operably connected to a RFID antenna.

In some embodiments, an appurtenance to a cavity wound dressing includes: at least one orientation indicator including an attachment region configured to affix to the porous wound dressing material. In some embodiments, an appurtenance to a cavity wound dressing includes: a porous wound dressing material suitable for attachment of the plurality of sensor units, the porous wound dressing material being flexible within a cavity wound.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures; and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures. In some embodiments, the appurtenance to a cavity wound dressing includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one orientation indicator attached to the edge region. In some embodiments, the appurtenance to a cavity wound dressing includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one temperature sensor unit attached to the edge region. In some embodiments, the appurtenance to a cavity wound dressing is functional when wet. In some embodiments, the appurtenance to a cavity wound dressing includes: a wound dressing, the wound dressing configured to be positioned within the wound cavity between the appurtenance and the wound surface; and a second wound dressing, the second wound dressing configured to cover a wound region and stabilize the appurtenance and the wound dressing during use, the second wound dressing configured to be removable from the wound region after use. In some embodiments, the appurtenance to a cavity wound dressing includes: a detachable cover configured to reversibly mate with the at least one wound-facing surface of the substrate.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes a structure including the wound- facing surface of a size and shape to approximate the surface of the cavity wound with a gap between the wound-facing surface of the substrate and a cavity wound surface. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes a three dimensional structure with at least one wound- facing surface, the at least one wound-facing surface of a size and shape to reversibly mate with the wound surface of the cavity wound. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes a non-porous, flexible structure. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound- facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes a porous, flexible structure. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes an interior region within the substrate, the interior region including one or more of the plurality of sensor units. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and wherein the substrate includes a plurality of unidirectional fluid flow structures attached to the apertures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound-facing surface to one or more of the plurality of sensor units attached to the substrate.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: a plurality of sensor units of at least two distinct types. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units of at least two distinct types are oriented as a pattern relative to the wound-facing surface. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: a plurality of sensor units including at least one sensor unit configured to detect physical pressure, at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record elapsed time. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: a plurality of sensor units including at least one sensor unit configured to detect at least one analyte in wound exudate. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one antenna operably connected to at least one sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one chemical-based sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one positional indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one fluid-activated sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one sensor unit including an optically resolvable detection indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate including at least one wound-facing surface, the wound- facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures, and a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures, wherein the plurality of sensor units include: at least one sensor unit including a detection indicator with an RFID antenna.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to associate with a cavity wound dressing; a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry; a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch. In some embodiments, the appurtenance to a cavity wound dressing includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one orientation indicator attached to the edge region. In some embodiments, the appurtenance to a cavity wound dressing includes: an edge region of the appurtenance, the edge region including at least one surface configured to be oriented away from the wound; and at least one temperature sensor unit attached to the edge region. In some embodiments, the appurtenance to a cavity wound dressing is functional when wet. In some embodiments, the appurtenance to a cavity wound dressing includes: a wound dressing, the wound dressing configured to be used in association with the appurtenance; and a wound covering, the wound covering configured to cover a wound region and stabilize the appurtenance and the wound dressing during use, the wound covering configured to be removable from the wound region after use. In some embodiments, the appurtenance to a cavity wound dressing includes: a detachable cover configured to reversibly mate with at least one wound-facing surface of the substrate. In some embodiments, the appurtenance to a cavity wound dressing includes: an indicator operably attached to the selectively actuatable switch. In some embodiments, the appurtenance to a cavity wound dressing includes: a battery. In some embodiments, the appurtenance to a cavity wound dressing includes: a processor; and a transceiver. In some embodiments, the appurtenance to a cavity wound dressing has been substantially sterilized. In some embodiments, the appurtenance to a cavity wound dressing includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on at least one sensor unit. In some embodiments, the appurtenance to a cavity wound dressing includes: a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on the wound-facing surface of the appurtenance.

In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to associate with a cavity wound dressing, wherein the substrate includes: a substantially planar, flexible structure. In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to associate with a cavity wound dressing, wherein the substrate includes: a structure configured to be placed within the cavity of a cavity wound in association with the cavity wound dressing. In some embodiments, an appurtenance to a cavity wound dressing includes: a substrate configured to associate with a cavity wound dressing, wherein the substrate is configured to irreversibly attach to the cavity wound dressing.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a transmitter unit; and a receiver. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit is configured to transmit a signal including information identifying the appurtenance. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit is configured to transmit a signal in response to an interrogation signal. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a radio frequency identification (RFID) device. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a passive radio frequency identification (RFID) device. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: an active radio frequency identification (RFID) device. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a Near Field Communication (NFC) device. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: non- volatile memory. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a processor. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, and a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry, wherein the transmission unit includes: a battery.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch includes: a connector between the transmission unit and the one or more sensor units. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch includes: a physical conduit configured to allow a liquid to flow through the appurtenance to a location in contact with the at least one antenna of the transmission unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch includes: a wire connecting the transmission unit and the one or more sensor units. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch is configured as a binary switch. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch is configured to be irreversible. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, and a selectively actuatable switch operably connected to the transmission unit, wherein the selectively actuatable switch is configured to be responsive to a change in capacitance.

In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: a plurality of sensor units of at least two distinct types oriented as a pattern relative to the wound-facing surface. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one sensor unit configured to detect physical pressure and temperature over time. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one sensor unit configured to detect at least one analyte in wound exudate. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one antenna operably attached to at least one sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one chemical-based sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one positional indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one fluid- activated sensor unit. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one sensor unit including an optically resolvable detection indicator. In some embodiments, an appurtenance to a cavity wound dressing includes a substrate configured to associate with a cavity wound dressing, a transmission unit attached to a surface of the substrate, a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch, wherein the one or more sensor units include: at least one sensor unit including an indicator with an RFID antenna.

In some embodiments, an appurtenance to a wound dressing includes: a substrate configured to fit substantially within a cavity wound in association with a wound dressing; and a plurality of sensor units attached to the substrate, each of the sensor units including a detector and an indicator, wherein the indicator includes a passive radio frequency identification (RFID) unit.

In some embodiments, a system for monitoring a cavity wound medical dressing includes: an appurtenance to a cavity wound dressing, the appurtenance including a substrate and a plurality of sensor units, wherein each of the sensor units include an indicator configured to respond to a specific external signal; and an external device configured to transmit the specific external signal and detect the response of the indicator included with each of the plurality of sensor units. All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in any Application Data Sheet, are incorporated herein by reference, to the extent not inconsistent herewith.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

What is claimed is:

Claims

1. An appurtenance to a wound dressing, comprising:

a substrate configured to mechanically or chemically attach to a wound dressing;

a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal; and

a projection operably attached to the transmission unit, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid associated with a wound.

2. The appurtenance to a wound dressing of claim 1, wherein the substrate comprises: a flexible material.

3. The appurtenance to a wound dressing of claim 1, wherein the transmission unit is configured to transmit the signal in response to an interrogation signal.

4. The appurtenance to a wound dressing of claim 1, wherein the transmission unit comprises:

a transmitter unit; and

a receiver.

5. The appurtenance to a wound dressing of claim 1, wherein the transmission unit comprises:

a radio frequency identification (RFID) device.

6. The appurtenance to a wound dressing of claim 1, wherein the transmission unit comprises:

at least two antennas.

7. The appurtenance to a wound dressing of claim 1, wherein the transmission unit comprises:

a Near Field Communication (NFC) device.

8. The appurtenance to a wound dressing of claim 1, wherein the transmission unit comprises:

a pressure sensitive activation region, wherein the pressure sensitive activation region includes a switch configured to be activated by physical pressure on a surface of the appurtenance.

9. The appurtenance to a wound dressing of claim 1, wherein the projection comprises:

a physical conduit configured for fluid flow from the interior region of the wound dressing to a location in contact with the transmission unit.

10. The appurtenance to a wound dressing of claim 1, wherein the projection

comprises:

a substantially hollow tubular structure.

11. The appurtenance to a wound dressing of claim 1 , wherein the projection

comprises:

one or more sensors; and

at least one substantially hollow enclosure substantially encircling the one or more

sensors, the at least one substantially hollow enclosure including one or more openings within the enclosure distal to an attachment to the substrate.

12. The appurtenance to a wound dressing of claim 1, wherein the projection

comprises:

one or more sensors configured to actuate a switch in the transmission unit in response to a stimulus.

13. The appurtenance to a wound dressing of claim 1, comprising:

one or more sensors; and

a connector between the transmission unit and the one or more sensors.

14. The appurtenance to a wound dressing of claim 1, comprising:

an indicator operably attached to the transmission unit.

15. An appurtenance to a wound dressing, comprising:

a substrate configured to attach to a wound dressing;

a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna operably attached to the circuitry;

a selectively actuatable switch operably connected to the transmission unit;

a projection operably attached to the substrate, the projection of a size and shape to extend into an interior region of a wound dressing; and

one or more sensors integral to the projection and operably connected to the selectively actuatable switch.

16. The appurtenance to a wound dressing of claim 15, wherein the transmission unit comprises: a radio frequency identification (RFID) device.

17. The appurtenance to a wound dressing of claim 15, wherein the transmission unit comprises:

a Near Field Communication (NFC) device.

18. The appurtenance to a wound dressing of claim 15, wherein the transmission unit comprises:

a processor.

19. The appurtenance to a wound dressing of claim 15, wherein the selectively

actuatable switch comprises:

a connector between the transmission unit and the one or more sensors.

20. The appurtenance to a wound dressing of claim 15, wherein the selectively

actuatable switch comprises:

a physical conduit configured to allow a liquid to flow from the interior region of the wound dressing to a location in contact with the at least one antenna of the transmission unit.

21. The appurtenance to a wound dressing claim 15, wherein the selectively actuatable switch is configured as a binary switch.

22. The appurtenance to a wound dressing of claim 15, wherein the selectively

actuatable switch is configured to be irreversible.

23. The appurtenance to a wound dressing of claim 15, wherein the selectively

actuatable switch is configured to be responsive to a change in capacitance.

24. The appurtenance to a wound dressing of claim 15, wherein the projection

comprises:

25. The appurtenance to a wound dressing of claim 15, wherein the one or more

sensors integral to the projection comprise:

one or more sensors configured to actuate the selectively actuatable switch in response to a stimulus.

26. The appurtenance to a wound dressing of claim 15, comprising:

an indicator operably attached to the selectively actuatable switch.

27. The appurtenance to a wound dressing of claim 15, comprising: a processor; and

a transceiver.

28. The appurtenance to a wound dressing of claim 15, wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on at least part of the projection.

29. An appurtenance to a wound dressing, comprising:

one or more sensors;

a processor operably attached to the one or more sensors;

at least one transmitter unit operably attached to the processor; and

an enclosure of a height and width to fit substantially within an interior region of a wound dressing.

30. The appurtenance to a wound dressing of claim 29, wherein the one or more

sensors comprise:

at least one sensor responsive to changes in capacitance.

31. The appurtenance to a wound dressing of claim 29, wherein the at least one

transmitter unit operably attached to the processor comprises:

a near field communication (NFC) device.

32. The appurtenance to a wound dressing of claim 29, wherein the enclosure

comprises:

one or more walls forming the enclosure; and

one or more openings within the one or more walls, the openings forming a conduit

between a region exterior to the enclosure and a region interior to the enclosure.

33. The appurtenance to a wound dressing of claim 29, wherein the processor and the at least one transmitter unit comprise:

a radio-frequency identification (RFID) device.

34. An appurtenance to a wound dressing, comprising:

a sensor unit including one or more sensors, the sensors positioned substantially within an enclosure of a height and width to fit substantially within an interior region of a wound dressing;

a transmission unit including a processor and at least one transmitter operably attached to the processor; and a connector between the sensor unit and the transmission unit, the connector configured to convey signals between the one or more sensors and the transmission unit.

35. An appurtenance to a wound dressing, comprising:

a substrate;

a passive radio frequency identification (RFID) unit attached to the substrate; and a substantially hollow projection operably attached to the substrate, the projection

including a first end and a second end, the first end of a size and shape to extend within a wound dressing, the second end extending into the passive radio frequency identification (RFID) unit.

36. A device, comprising:

a wound dressing;

a transmission unit irreversibly attached to the wound dressing, the transmission unit including circuitry and at least one antenna;

a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending within an interior region of the wound dressing.

37. A wound dressing unit, comprising:

a wound dressing;

a substrate attached to an external surface of the wound dressing;

a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal;

a selectively actuatable switch operably connected to the transmission unit; and a projection operably attached to the switch, the projection extending through the external surface of the wound dressing.

38. An appurtenance to a wound dressing, comprising:

a substrate configured to attach to a wound dressing;

a fluid-activated voltaic cell attached to the substrate;

a transmission unit attached to a surface of the substrate, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell; and a projection operably attached to the fluid-activated voltaic cell, the projection of a size and shape to extend into an interior region of the wound dressing and configured to sample a fluid within the interior region of the wound dressing.

39. The appurtenance of claim 38, wherein the fluid-activated voltaic cell comprises: at least one enhancement unit configured to release at least one chemical enhancer of an electrochemical reaction within the fluid-activated voltaic cell in response to contact with the fluid, wherein the at least one enhancement unit includes at least one dry acid unit configured to release an acid when contacted by a liquid.

40. The appurtenance of claim 38, wherein the fluid-activated voltaic cell comprises: a chamber configured to receive the fluid.

41. The appurtenance of claim 38, wherein the transmission unit comprises:

a radio frequency identification (RFID) unit.

42. The appurtenance of claim 38, wherein the transmission unit comprises:

a near field communication (NFC) unit.

43. The appurtenance of claim 38, wherein the transmission unit comprises:

a unique identifier.

44. The appurtenance of claim 38, wherein the transmission unit comprises:

a processor.

45. The appurtenance of claim 38, wherein the projection comprises:

at least one substantially hollow tube with a first aperture at a location adjacent to the interior region of the wound dressing and a second aperture at a location adjacent to a surface of the fluid- activated voltaic cell.

46. The appurtenance of claim 38, wherein the projection comprises:

a plurality of apertures located along a length of the projection; and

a plurality of conduits, each conduit including a first end attached to one of the plurality of apertures, and a second end attached to the fluid-activated voltaic cell, each conduit configured to direct the fluid from the interior region of the wound dressing into the fluid-activated voltaic cell.

47. The appurtenance of claim 38, wherein the projection is partially positioned within the fluid-activated voltaic cell, and wherein the projection includes an aperture within the fluid-activated voltaic cell.

48. The appurtenance of claim 38, comprising:

a wire connector between the fluid-activated voltaic cell and the transmission unit.

49. The appurtenance of claim 38, comprising:

a passive radio frequency identification (RFID) unit including an identifier.

50. The appurtenance of claim 38, comprising:

a second fluid-activated voltaic cell attached to the substrate and configured to activate the transmission unit; and

a second projection operably attached to the second fluid-activated voltaic cell, the second projection configured to sample a second fluid within a second interior region of the wound dressing.

51. The appurtenance of claim 38, comprising:

a sensor connected to the transmission unit.

52. An appurtenance to a wound dressing, comprising:

an enclosure of a height and width to fit substantially within an interior region of a wound dressing, the enclosure including at least one aperture configured to allow a fluid to flow from the interior region of the wound dressing into the enclosure;

a fluid-activated voltaic cell attached to one or more of the at least one aperture; and a transmission unit attached to an internal surface of the enclosure, the transmission unit including circuitry and at least one antenna, the transmission unit configured to transmit a signal in response to the fluid-activated voltaic cell.

53. The appurtenance of claim 52, wherein the enclosure comprises:

a substantially cylindrical structure, wherein a largest width of the substantially cylindrical structure is less than a smallest width of the wound dressing.

54. The appurtenance of claim 52, wherein the enclosure comprises:

a substantially pyramidal structure, wherein a largest width of the substantially pyramidal structure is less than a smallest width of the wound dressing.

55. The appurtenance of claim 52, wherein the enclosure comprises:

one or more walls, the walls forming a flange on an edge of the enclosure, the flange

positioned to attach a fastener between a surface of the wound dressing and the enclosure.

56. The appurtenance of claim 52, wherein the enclosure comprises:

a substantially hollow tube.

57. The appurtenance of claim 52, wherein the enclosure comprises:

a plurality of apertures.

58. The appurtenance of claim 52, wherein the at least one aperture of the enclosure comprises:

a micro-capillary film configured to direct the fluid from the interior region of the wound dressing into an interior of the enclosure.

59. The appurtenance of claim 52, wherein the at least one aperture of the enclosure comprises:

a conduit configured to direct the fluid from the interior region of the wound dressing into an interior of the enclosure.

60. The appurtenance of claim 52, wherein the fluid-activated voltaic cell comprises: at least one enhancement unit configured to release at least one chemical enhancer of an electrochemical reaction within the fluid-activated voltaic cell in response to contact with the fluid, wherein the at least one enhancement unit includes at least one dry acid unit configured to release acid when contacted by a liquid.

61. The appurtenance of claim 52, wherein the fluid-activated voltaic cell comprises: a chamber configured to receive the fluid.

62. The appurtenance of claim 52, wherein the transmission unit comprises:

a radio frequency identification (RFID) unit.

63. The appurtenance of claim 52, wherein the transmission unit comprises:

a near filed communication (NFC) unit.

64. The appurtenance of claim 52, wherein the transmission unit comprises:

a unique identifier.

65. The appurtenance of claim 52, wherein the transmission unit comprises:

a processor.

66. The appurtenance of claim 52, comprising:

67. The appurtenance of claim 52, comprising:

a passive radio frequency identification (RFID) unit including an identifier.

68. The appurtenance of claim 52, comprising:

a second fluid-activated voltaic cell attached to at least one second aperture, the at least one second aperture configured to allow a fluid to flow from a second interior region of the wound dressing into an interior of the second fluid-activated voltaic cell.

69. The appurtenance of claim 52, comprising: a sensor attached to the at least one aperture of the enclosure; and

a connection between the sensor and the transmission unit.

70. An appurtenance to a wound dressing, comprising:

an appurtenance configured to attach to a wound dressing, the appurtenance including a conduit configured to allow a fluid to flow from an interior region of the wound dressing into the appurtenance;

a fiuid-activated voltaic cell including an internal chamber, the internal chamber attached to the conduit; and

a radio frequency identification (RFID) unit attached to the fluid-activated voltaic cell and configured to operate in response to electrical power generated by the fluid- activated voltaic cell.

71. The appurtenance of claim 70, wherein the conduit comprises:

a plurality of microchannels configured to direct the fluid to flow into the fluid-activated voltaic cell.

72. The appurtenance of claim 70, wherein the conduit comprises:

at least one projection, the projection including at least one aperture positioned distal to the appurtenance, the projection configured to allow the fluid to flow from the interior region of the wound dressing into the appurtenance.

73. The appurtenance of claim 70, wherein the fluid-activated voltaic cell comprises: at least one enhancement unit configured to release at least one chemical enhancer of an electrochemical reaction within the fluid-activated voltaic cell in response to contact with the fluid, wherein the at least one enhancement unit includes at least one dry acid unit configured to release an acid when contacted by a liquid.

74. The appurtenance of claim 70, wherein the fluid-activated voltaic cell comprises: a chamber attached to the conduit, the chamber configured to receive the fluid.

75. The appurtenance of claim 70, wherein the radio frequency identification (RFID) unit comprises:

a unique identifier.

76. The appurtenance of claim 70, wherein the radio frequency identification (RFID) unit comprises:

an antenna; and

circuitry configured to initiate a signal transmission from the antenna.

77. The appurtenance of claim 70, wherein the radio frequency identification (RFID) unit comprises:

a processor.

78. The appurtenance of claim 70, comprising:

a second conduit positioned to allow the fluid to flow from a second interior region of the wound dressing into the appurtenance; and

a second fluid-activated voltaic cell including a second internal chamber, the second

internal chamber attached to the second conduit, wherein the second fluid-activated voltaic cell is configured to direct current to the radio frequency identification (RFID) unit.

79. The appurtenance of claim 70, comprising:

a sensor attached to the conduit; and

a connector between the sensor and the radio frequency identification (RFID) unit.

80. An appurtenance to a cavity wound dressing, comprising:

a substrate including at least one wound- facing surface, the wound-facing surface

configured to be oriented facing a wound surface of a cavity wound; and a plurality of sensor units attached to the substrate, the plurality of sensor units oriented and positioned on the substrate relative to the wound surface of the cavity wound.

81. The appurtenance to a cavity wound dressing of claim 80, wherein the substrate comprises:

a plurality of unidirectional fluid flow structures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound- facing surface to one or more of the plurality of sensor units attached to the substrate.

82. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise:

a plurality of sensor units of at least two distinct types.

83. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise:

at least one sensor unit configured to detect physical pressure, at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record an elapsed time value.

84. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise: at least one sensor unit configured to detect one or more analytes of wound exudate.

85. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise:

at least one antenna operably connected to at least one sensor unit.

86. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise:

at least one chemical-based sensor unit.

87. The appurtenance to a cavity wound dressing of claim 80, wherein the plurality of sensor units attached to the substrate comprise:

at least one sensor unit including an optically resolvable detection indicator.

88. The appurtenance to a cavity wound dressing of claim 80, comprising:

an edge region of the appurtenance, the edge region including at least one surface

configured to be oriented away from the wound and at least one surface configured to be oriented facing a periwound region of the cavity wound; and

at least one temperature sensor unit attached to the edge region.

89. An appurtenance to a cavity wound dressing, comprising:

a plurality of sensor units, wherein each sensor unit includes an attachment region

configured to affix to a porous wound dressing material and wherein each sensor unit is configured to be operational when in contact with fluid, is configured to be operational at temperatures between 35 degrees Centigrade and 40 degrees

Centigrade, and under physical pressure up to 32 mm Hg; and

the plurality of sensor units in the aggregate of a size and mass to allow for medical use with the porous dressing material at the cavity wound.

90. The appurtenance of claim 89, wherein the plurality of sensor units comprise: a plurality of sensor units including at least two distinct types of sensor units.

91. The appurtenance of claim 89, wherein the plurality of sensor units comprise: a plurality of sensor units including at least one sensor unit configured to detect physical pressure, and at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record an elapsed time value.

92. The appurtenance of claim 89, wherein the plurality of sensor units comprise: at least one antenna operably attached to at least one sensor unit.

93. The appurtenance of claim 89, wherein the plurality of sensor units comprise: at least one chemical-based sensor unit.

94. The appurtenance of claim 89, wherein the plurality of sensor units comprise: at least one temperature sensor unit.

95. The appurtenance of claim 89, wherein the plurality of sensor units comprise: at least one pressure sensor unit.

96. The appurtenance of claim 89, wherein the plurality of sensor units comprise: at least one sensor unit including an optically resolvable detection indicator.

97. An appurtenance to a cavity wound dressing, comprising:

a substrate including at least one wound-facing surface, the wound-facing surface of a size and shape for positioning within a cavity wound, wherein the substrate includes a plurality of apertures; and

a plurality of sensor units attached to the substrate, each of the plurality of sensor units oriented and positioned on the substrate relative to at least one of the plurality of apertures.

98. The appurtenance of claim 97, wherein the substrate comprises:

an interior region within the substrate, the interior region including one or more of the plurality of sensor units.

99. The appurtenance of claim 97, wherein the substrate comprises:

a plurality of unidirectional fluid flow structures attached to the apertures, wherein the unidirectional fluid flow structures are configured to allow fluid flow from the wound-facing surface to one or more of the plurality of sensor units attached to the substrate.

100. The appurtenance of claim 97, wherein the plurality of sensor units attached to the substrate comprises:

a plurality of sensor units of at least two distinct types.

101. The appurtenance of claim 97, wherein the plurality of sensor units attached to the substrate comprises:

a plurality of sensor units including at least one sensor unit configured to detect physical pressure, at least one sensor unit configured to detect temperature, and at least one sensor unit configured to record elapsed time.

102. The appurtenance of claim 97, wherein the plurality of sensor units attached to the substrate comprises:

at least one antenna operably connected to at least one sensor unit.

103. The appurtenance of claim 97, wherein the plurality of sensor units attached to the substrate comprises:

at least one chemical-based sensor unit.

104. The appurtenance of claim 97, wherein the plurality of sensor units attached to the substrate comprises:

at least one sensor unit including an optically resolvable detection indicator.

105. An appurtenance for monitoring a cavity wound, comprising:

a substrate configured to associate with a cavity wound dressing;

a selectively actuatable switch operably connected to the transmission unit; and one or more sensor units affixed to the substrate and operably connected to the selectively actuatable switch.

106. The appurtenance of claim 105, wherein the transmission unit comprises:

a radio frequency identification (RFID) device.

107. The appurtenance of claim 105, wherein the wherein the selectively actuatable switch comprises:

a physical conduit configured to allow a liquid to flow through the appurtenance to a location in contact with the at least one antenna of the transmission unit.

108. The appurtenance of claim 105, wherein the wherein the selectively actuatable switch is configured as a binary switch.

109. The appurtenance of claim 105, wherein the wherein the selectively actuatable switch is configured to be responsive to a change in capacitance.

110. The appurtenance of claim 105, wherein the wherein the one or more sensor units affixed to the substrate comprise:

at least one antenna operably attached to at least one sensor unit.

111. The appurtenance of claim 105, wherein the wherein the one or more sensor units affixed to the substrate comprise:

at least one sensor unit including an optically resolvable detection indicator.

112. The appurtenance of claim 105, wherein the transmission unit includes a pressure sensitive activation region, wherein the pressure sensitive activation region is configured to be activated by physical pressure on the wound-facing surface of the appurtenance.

113. An appurtenance to a cavity wound dressing, comprising:

a substrate configured to fit substantially within a cavity wound in association with a wound dressing; and

a plurality of sensor units attached to the substrate, each of the sensor units including a detector and an indicator, wherein the indicator includes a passive radio frequency identification (RFID) unit.

114. A system for monitoring a cavity wound medical dressing, comprising:

an appurtenance to a cavity wound dressing, the appurtenance including a substrate and a plurality of sensor units, wherein each of the sensor units include an indicator configured to respond to a specific external signal; and

an external device configured to transmit the specific external signal and detect the

response of the indicator included with each of the plurality of sensor units.