WO2022263938A1

WO2022263938A1 - Fistula ring

Info

Publication number: WO2022263938A1
Application number: PCT/IB2022/054469
Authority: WO
Inventors: Martin W. Steiner
Original assignee: Kci Manufacturing Unlimited Company
Priority date: 2021-06-15
Filing date: 2022-05-13
Publication date: 2022-12-22

Abstract

A fistula device for suctioning effluent emitted by a fistula includes an outer ring member, an inner ring member, and a first tubular member. The outer ring member includes an interior surface and an exterior surface positioned apart. The inner ring member is positioned within the outer ring member and includes an interior surface and an exterior surface positioned apart. The inner ring member defines a sealed inner volume in fluidic communication with a fistula. The inner ring member and the outer ring member are centered about a common axis. The first tubular member is in fluidic communication with the sealed inner volume and fluidly coupled with a first negative pressure source to draw a negative pressure within the sealed inner volume. The first tubular member is configured to transport effluent emitted by the fistula into the sealed inner volume out of the sealed inner volume.

Description

FISTULA RING

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of priority to U.S. Provisional Application No. 63/210,813, filed on June 15, 2021, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] The present disclosure relates generally to fistula devices. Fistulas can form between a patient’s bodily cavity or on an exterior surface over a patient’s bodily cavity. Fistulas may heal themselves over time but may produce effluent which can infect surrounding tissue. Removing the effluent and ensuring that the effluent does not contact or infect surrounding tissue can facilitate healing progress of the fistula.

SUMMARY

[0003] One implementation of the present disclosure is a fistula device for suctioning effluent emitted by a fistula, according to some embodiments. The device includes an outer ring member, an inner ring member, and a first tubular member. The outer ring member includes an interior surface and an exterior surface positioned a first wall thickness apart. The inner ring member is positioned within the outer ring member and includes an interior surface and an exterior surface positioned a second wall thickness apart. The inner ring member defines a sealed inner volume in fluidic communication with a fistula. The inner ring member and the outer ring member are centered about a common axis. The first tubular member is in fluidic communication with the sealed inner volume and fluidly coupled with a first negative pressure source to draw a negative pressure within the sealed inner volume. The first tubular member is configured to transport effluent emitted by the fistula into the sealed inner volume out of the sealed inner volume.

[0004] Another implementation of the present disclosure is a fistula dressing, according to some embodiments. The fistula dressing includes an inner ring member, an outer ring member, a first tubular member, and a second tubular member. The inner ring member is positioned within the outer ring member and defines a first inner volume that is fluidly coupled with a fistula. The first tubular member and the second tubular member extend through a side of the inner ring member and the outer ring member to the first inner volume. At least one of the first tubular member or the second tubular member are fluidly coupled with a first negative pressure source to draw effluent emitted by the fistula out of the first inner volume.

[0005] Another implementation of the present disclosure is a fistula device for suctioning effluent emitted from a fistula, according to some embodiments. The fistula device includes a ring member, a drape layer, a first tube, and a second tube. The ring member has a top side, a bottom side configured for placement on a patient about a fistula, and a sidewall. The drape layer extends over the top side of the ring and has a wing portion sealable to a patient outside the sidewall. The drape layer and sidewall define a closed inner volume when placed over the fistula. The first tube extends through the sidewall and has a first end communicating with the inner volume and a second end configured to engage a suction source. The second tube extends through the sidewall and has a first end communicating with the inner volume and a second end configured to selectively engage an irrigation fluid source and an air supply source.

[0006] Another implementation of the present disclosure is a method of treating a fistula, according to some embodiments. The method includes placing a ring member around a fistula. The ring member has a top side, a bottom side, and a sidewall. The ring member also includes a first tube and a second tube extending through the sidewall. The method also includes covering the ring member with a drape to define a closed inner volume over the fistula. The method also includes venting the closed inner volume to atmosphere through the second tube. The method also includes drawing suction on the inner volume through the first tube. The method also includes suctioning a fistula effluent from the inner volume through the first tube when fistula effluent reaches the first tube.

[0007] Those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices and/or processes described herein, as defined solely by the claims, will become apparent in the detailed description set forth herein and taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements, in which:

[0009] FIG. 1 is a perspective view of a fistula ring that can be used to suction effluent from a first inner volume including a first tubular member and a second tubular member, according to an exemplary embodiment;

[0010] FIG. 2 is a side sectional view of the fistula ring of FIG. 1, showing positioning of the first tubular member and the second tubular member;

[0011] FIG. 3 is a side sectional view of the fistula ring of FIG. 1, showing the first inner volume sealed with a drape, according to an exemplary embodiment;

[0012] FIG. 4 is a side sectional view of the fistula ring of FIG. 1, showing the first tubular member vented to atmospheric pressure and the second tubular member fluidly coupled with a negative pressure source when a fluid level of effluent within the first inner volume is at a first level, according to an exemplary embodiment;

[0013] FIG. 5 is a side sectional view of the fistula ring of FIG. 4, showing the first tubular member vented to atmospheric pressure and the second tubular member fluidly coupled with the negative pressure source when the fluid level of effluent within the first inner volume is at a second level, according to an exemplary embodiment; [0014] FIG. 6 is a side sectional view of the fistula ring of FIG. 1, showing a negative pressure source configured to draw a negative pressure at a second inner volume defined by an outer drape layer, according to an exemplary embodiment;

[0015] FIG. 7 is a side sectional view of the fistula ring of FIG. 1 showing the first tubular member fluidly coupled with an instillation source and the second tubular member fluidly coupled with the negative pressure source, according to an exemplary embodiment;

[0016] FIG. 8 is a flow diagram of a process for providing the fistula ring of FIGS. 1-7, according to an exemplary embodiment;

[0017] FIG. 9 is a flow diagram of process for using the fistula ring of FIGS. 1-7, according to an exemplary embodiment;

[0018] FIG. 10 is a block diagram of a wound therapy system including a therapy device coupled to a wound dressing via tubing which is usable with the fistula ring of FIGS. 1-7, according to an exemplary embodiment;

[0019] FIG. 11 is a block diagram illustrating the therapy device of FIG. 10 in greater detail when the therapy device operates to draw a vacuum within a negative pressure circuit, according to an exemplary embodiment;

[0020] FIG. 12A is a block diagram illustrating the therapy device of FIG. 10 in greater detail when the therapy device operates to vent the negative pressure circuit, according to an exemplary embodiment;

[0021] FIG. 12B is a block diagram illustrating the therapy device of FIG. 10 in greater detail when the therapy device uses an orifice to vent the negative pressure circuit, according to an exemplary embodiment;

[0022] FIG. 13 is a block diagram illustrating the therapy device of FIG. 10 in greater detail when the therapy device operates to deliver instillation fluid to the wound dressing and/or a wound, according to an exemplary embodiment;

[0023] FIG. 14 is a flow diagram of a process for treating a fistula, according to an exemplary embodiment;

[0024] FIG. 15 is a perspective view of a fistula ring that can be used to suction effluent from a first inner volume including a first tubular member and a second tubular member, according to an exemplary embodiment;

[0025] FIG. 16 is a side sectional view of the fistula ring of FIG. 15, according to an exemplary embodiment; and

[0026] FIG. 17 is a top view of an inner ring member of the fistula ring of FIG. 1 including a pie shaped cutout, according to an exemplary embodiment; and

[0027] FIG. 18 is a top view of an inner ring member of the fistula ring of FIG. 1 including an irregularly shaped cutout, according to an exemplary embodiment. DETAILED DESCRIPTION

Overview

[0028] Referring generally to the FIGURES, a fistula ring includes an inner or first ring member, an outer or second ring member, a first tube, and a second tube. The inner ring member may be positioned within the outer ring member and can have a shape corresponding to a shape of the outer ring member. The inner ring member and the outer ring member may each have a sidewall and may cooperatively define a sidewall portion. An exterior surface of the inner ring member may contact, abut, engage, etc., an interior surface of the outer ring member.

[0029] The inner ring member can include a top side having a top lateral surface and a top opening, and a bottom side having a bottom lateral surface and a bottom opening. The inner ring member can be wrapped or covered in a drape layer that extends along the exterior surface of the inner ring member and seals the top opening. The inner ring member can include an adhesive member along the bottom lateral surface that is configured to sealingly couple or adhere to tissue surrounding a fistula.

In this way, the inner ring member can be placed over the fistula and may seal with tissue surrounding the fistula. The drape layer and the inner ring member may form or define a closed inner volume which may fluidly communicate with the fistula through the bottom opening of the inner ring member.

[0030] The outer ring member surrounds the inner ring member and can be positioned within another volume that is defined by another drape layer. The other drape layer may be an exterior or outer drape layer that covers the inner ring member and the outer ring member and includes wing portions that sealingly couple with the tissue surrounding the fistula or the outer ring member.

[0031] The first tube and the second tube extend through the sidewalls of the inner ring member and the outer ring member and fluidly couple with the closed inner volume. The first tube may be positioned below the first tube or closer to the fistula or the bottom opening than the second tube. The first tube can be fluidly coupled at an opposite end with a suction or negative pressure source. In one embodiment, the second tube is vented to the atmosphere so that as the first tube draws suction at the closed inner volume, air may enter the closed inner volume through the second tube.

[0032] As the fistula emits effluent into the closed inner volume, the effluent may reach the first tube. Once the effluent reaches the first tube, the suction or negative pressure draws the effluent through the first tube. In this way, the suction or negative pressure can be provided continuously to the closed inner volume through the first tube but is only used to remove effluent when the effluent reaches the first tube.

[0033] The second tube may also be fluidly coupled at the opposite end with an instillation source instead of being vented to atmospheric pressure. The second tube and the instillation source may actively provide effluent to the closed inner volume (e.g., using a pump) or may passively provide effluent to the closed inner volume (e.g., due to the suction drawn through the first tube). Providing instillation fluid to the closed inner volume may result in the instillation fluid mixing with the effluent and reducing a viscosity of the effluent. Reducing the viscosity of the effluent can facilitate egress or removal of the effluent from the closed inner volume through the first tube and may reduce a likelihood that the effluent will clog as it is removed from the closed inner volume through the first tube. Advantageously, providing the first tube and the second tube through the side of the inner ring member and the outer ring member facilitates a smaller or lower profile fistula ring which may facilitate placement of the fistula ring between bodily cavity walls.

Fistula Ring

[0034] Referring particularly to FIG. 1, a fistula ring, a dressing, a fistula dressing, a cylindrical dressing, etc., shown as fistula ring 10 is shown, according to an exemplary embodiment. Fistula ring 10 may be used to provide negative pressure to periwound tissue surrounding a fistula 22. For example, fistula ring 10 may be a low-profile dressing that can be positioned between abdominal walls, or topically applied to an external fistula. In this way, fistula ring 10 can be advantageously used for both internal fistulas that may occur between bodily cavities, or can be applied to an external fistula on a patient’s skin.

[0035] Fistulas may occur under an abdominal wall and can be difficult to access with conventional fistula devices or fistula dressings. Fistulas may close on their own over time if they are non productive (e.g., do not emit effluent) and provided proper negative pressure. In some cases, a caregiver may not desire to provide strong negative pressure over the fistula if attempting to close the fistula.

[0036] Fistula ring 10 includes an inner foam ring 12 (e.g., a first ring member, a first member, a first foam member, an interior member, a resilient member, etc.) and an outer foam ring 14 (e.g., a second ring member, a second member, a second foam member, an exterior member, an annular member, etc.). Inner foam ring 12 may have a structural strength, rigidity, or a resilience that is greater than a structural strength, rigidity, or resilience of outer foam ring 14. It should be understood that while inner foam ring 12 and outer foam ring 14 are shown having a circular or cylindrical shape, inner foam ring 12 and outer foam ring 14 may have any other shape such as an elliptical shape, a square shape, a hexagonal shape, an irregular shape, a curved shaped, etc.

[0037] Inner foam ring 12 includes an interior surface 26 (e.g., a radially inwards facing surface, an inner periphery, an inner edge, an inwards facing surface, etc.) and an exterior surface 28 (e.g., a radially outwards facing surface, an outer periphery, an outer edge, an outwards facing surface, etc.). Inner foam ring 12 can define an inner volume 24 therewithin (e.g., a space, a void, etc.). In some embodiments, inner volume 24 is defined as space inwards relative to interior surface 26 of inner foam ring 12.

[0038] Inner foam ring 12 can be positioned within outer foam ring 14 as shown in FIG. 1. Outer foam ring 14 may have a shape that corresponds to a shape of inner foam ring 12 so that inner foam ring 12 and outer foam ring 14 fit together as shown. Outer foam ring 14 includes an interior surface 30 (e.g., a radially inwards facing surface, an inner periphery, an inner edge, an inwards facing surface, etc.) and an exterior surface 32 (e.g., a radially outwards facing surface, an outer periphery, an outer edge, an outwards facing surface, etc.). In some embodiments, inner foam ring 12 and outer foam ring 14 are concentric with each other about a shared central axis . For example, inner foam ring 12 may be positioned within outer foam ring 14 so that exterior surface 28 of inner foam ring 12 directly contacts, engages, abuts, touches, etc., interior surface 30 of outer foam ring 14. In some embodiments, a gap is formed between exterior surface 28 of inner foam ring 12 and interior surface 30 of outer foam ring 14. Inner foam ring 12 may have a wall thickness 42 that is substantially equal to a wall thickness 44 of outer foam ring 14. In other embodiments, wall thickness 42 of inner foam ring 12 is greater than wall thickness 44 of outer foam ring 14. In still other embodiments, wall thickness 42 of inner foam ring 12 is less than wall thickness 44 of outer foam ring 14.

[0039] Fistula ring 10 may include a first drape, a first adhesive layer, a first polymer layer, etc., shown as first drape 16. First drape 16 may cover inner foam ring 12 and outer foam ring 14. First drape 16 may seal with a patient’s tissue 17 surrounding fistula 22. For example, first drape 16 may sealingly couple with the patient’s periwound tissue 17 along a circumference about fistula 22.

[0040] Referring still to FIG. 1, fistula ring 10 can include a vent tube 18 (e.g., a first tubular member, a first conduit, a first pipe, etc.) and a suction tube 20 (e.g., a second tubular member, a second conduit, a second pipe, etc.). Vent tube 18 and suction tube 20 may extend through inner foam ring 12 and outer foam ring 14. In some embodiments, vent tube 18 extends through an opening 76 in inner foam ring 12 and/or outer foam ring 14, while suction tube 20 extends through an opening 78 in inner foam ring 12 and/or outer foam ring 14. Vent tube 18 and suction tube 20 may extend in a radial direction relative to central axis 46 through inner foam ring 12 and outer foam ring 14. In some embodiments, vent tube 18 and suction tube 20 extend out of a side of inner foam ring 12 and outer foam ring 14. Advantageously, providing vent tube 18 and suction tube 20 through the side of inner foam ring 12 and outer foam ring 14 facilitates a reduced overall height of fistula ring 10 (along central axis 46), thereby providing a fistula ring with a smaller profile that can be positioned between bodily walls.

[0041] In some embodiments, suction tube 20 is fluidly coupled at one end with inner volume 24 or a sealed inner volume of inner foam ring 12, and fluidly coupled with a negative pressure source (e.g., a wall negative pressure source such as from a building suction source accessible in a treatment room from a wall-mounted valve, fitting, or the like, a constant negative pressure source, an adjustable negative pressure source, etc.) at an opposite or distal end. Vent tube 18 can be vented to atmospheric pressure.

[0042] It should be understood that fistula ring 10 may be provided in a variety of overall sizes, heights, etc. For example, fistula ring 10 can be provided in a small, medium and large size, a customized size, etc., for treatment of a fistula having a particular size. For example, inner foam ring 12 and outer foam ring 14 can be provided having different diameters or radii so that fistula 10 can be used with a larger or smaller fistula 22. Likewise, fistula ring 10 may be provided with different heights. For example, in one embodiment, inner foam ring 12 and outer foam ring 14 may have a particular height that is sufficient to accommodate larger vent tubes 18 and suction tubes 20, while in another embodiment, inner foam ring 12 and outer foam ring 14 may have a smaller height that accommodates smaller vent tubes 18 and suction tubes 20. In some embodiments, the size, shape, inner diameter, outer diameter, etc., of inner foam ring 12 and outer foam ring 14 are sized for a particular fistula 22.

[0043] Additionally, inner foam ring 12 and outer foam ring 14 may have an irregular or customizable shape or inner periphery. For example, as shown in FIGS. 17 and 18, inner foam ring 12 may be provided as a substantially filled disc-shaped member. Inner foam ring 12 can have a pie shaped cutout 82 (as shown in FIG. 17), an irregular shaped cutout 84 (as shown in FIG. 18), a square-shaped cutout, etc., or any other shaped cutout so that fistula ring 10 can be used to treat fistulas 22 with unusual shapes. The cutout may define interior surface 26 and inner volume 24. The cutout may be positioned proximate a sidewall or outer periphery of inner foam ring 12 so that fistula ring 10 can be used to treat fistulas that are positioned near the outer periphery of inner foam ring 12. [0044] It should also be understood that inner foam ring 12 and/or outer foam ring 14 may be manufactured from or made from a material other than foam. For example, inner foam ring 12 and/or outer foam ring 14 may be manufactured from a material that has higher resilience or structural strength than foam to provide additional rigidity for fistula ring 10.

[0045] Referring particularly to FIGS. 2 and 3, a side sectional view of fistula ring 10 is shown, according to an exemplary embodiment. Fistula ring 10 can include an adhesive, a glue, etc., shown as adhesive member 34. In some embodiments, adhesive member 34 is positioned along a bottom surface 52 of inner foam ring 12. Adhesive member 34 can facilitate a sealed coupling between inner foam ring 12 and the patient’s periwound tissue 17. In some embodiments, atop lateral opening 56 of inner foam ring 12 is sealed. Top lateral opening 56 of inner foam ring 12 may be sealed independently of first drape 16 (e.g., using a second drape as described in greater detail below with reference to FIG. 3). A bottom lateral opening 54 of inner roam ring 12 may be open so that inner volume 24 is fluidly coupled with fistula 22.

[0046] Referring particularly to FIG. 2, suction tube 20 may be positioned a distance 50 from bottom lateral opening 54 (e.g., a bottom lateral periphery or edge of inner foam ring 12). Likewise, vent tube 18 may be positioned a distance 48 from bottom lateral opening 54. In some embodiments, distances 48 and 50 are measured along central axis 46. Distance 48 may be greater than distance 50 so that vent tube 18 is positioned above suction tube 20 or so that a distance between vent tube 18 and fistula 22 is greater than a distance between suction tube 20 and fistula 22. In this way, as effluent or fluid emitted from fistula 22 builds up within inner volume 24, the effluent may first contact suction tube 20.

[0047] Referring particularly to FIG. 3, fistula ring 10 can include a second drape 36 that is configured to define a sealed inner volume 38 within inner foam ring 12. In some embodiments, second drape 36 extends along exterior surface 28 of inner foam ring 12, top lateral opening 56 of inner foam ring 12, and sealingly couples with adhesive member 34. Second drape 36, inner foam ring 12 and adhesive member 34 can cooperatively define or form sealed inner volume 38. Sealed inner volume 38 may be defined along second drape 36 at top lateral opening 56, interior surface 26 of inner foam ring 12, periwound tissue 17, and fistula 22. In some embodiments, sealed inner volume 38 is the same as inner volume 24 but is fluidly coupled with fistula 22 so that effluent emitted by fistula 22 may enter sealed inner volume 38 but is prevented from leaking out of sealed inner volume 38. In this way, second drape 36 may facilitate an independently accessible and sealed inner volume 38 that is within an inner volume defined by first drape 16. In some embodiments, sealed inner volume 38 is defined by first drape 16. For example, second drape 36 may be an optional component and first drape 16 may be used to define sealed inner volume 38. In some embodiments, first drape 16 extends beyond outer foam ring 14 and portions of first drape 16 that extend beyond outer foam ring 14 are “wing” portions. These wing portions may sealingly couple or adhere with patient’s tissue 17 surrounding outer foam ring 14.

[0048] Referring particularly to FIGS. 4 and 5, the function of suction tube 20 and vent tube 18 is shown in greater detail, according to an exemplary embodiment. Fistula 22 may emit effluent 40 into sealed inner volume 38 through bottom lateral opening 54. As effluent 40 builds up within sealed inner volume 38, effluent 40 may have a fluid level 43 relative to bottom lateral opening 54. In some embodiments, effluent 40 is in fluidic communication with suction tube 20 when fluid level 43 reaches a particular level 45 relative to bottom lateral opening 54. In some embodiments, the particular level 45 is substantially equal to distance 50 between suction tube 20 and bottom lateral opening 54. In some embodiments, the particular level 45 is slightly less than distance 50 between suction tube 20 and bottom lateral opening 54 (e.g., a distance between a bottom of an inner volume of suction tube 20 and bottom lateral opening 54).

[0049] Vent tube 18 fluidly couples with sealed inner volume 38 at first end 66 (e.g., a proximate end, a fistula-proximate end, etc.), and is vented to atmospheric pressure at second end 68 (e.g., a distal end, a fistula-distal end, etc.). Likewise, suction tube 20 fluidly couples with sealed inner volume 38 at first end 70 (e.g., a proximate end, a fistula-proximate end, etc.), and may be fluidly coupled with a negative pressure source 62 at second end 72 (e.g., a distal end, a fistula-distal end, etc.). In some embodiments, negative pressure source 62 is a wall source (e.g., a wall negative pressure source such as from a building suction source accessible in a treatment room from a wall- mounted valve, fitting, or the like), a suction pump, etc. Negative pressure source 62 may be configured to draw air and/or effluent from sealed inner volume 38. In some embodiments, negative pressure source 62 is therapy device 602.

[0050] When the fluid level 43 is less than the particular level 45 (e.g., when effluent 40 does not reach suction tube 20), negative pressure source 62, suction tube 20, and vent tube 18 may circulate air through sealed inner volume 38 (as shown in FIG. 4) with inner volume 38 remaining at atmospheric pressure so that negative pressure is not drawn on fistula 22. As fistula 22 produces or emits additional effluent 40, effluent 40 may reach suction tube 20 (e.g., fluid level 45 reaches, is equal to, or is greater than the particular level 45) and be drawn out of sealed inner volume 38 through suction tube 20. In this way, the negative pressure drawn at sealed inner volume 38 by negative pressure source 62 through suction tube 20 is only used to suction effluent 40 from sealed inner volume 38 when effluent 40 reaches suction tube 20, and without drawing negative pressure on fistula 22

[0051] Effluent 40 may be drawn out of sealed inner volume 38 through suction tube 20 when it sufficiently accumulates. Advantageously, removing effluent 40 from sealed inner volume 38 facilitates reducing a likelihood that effluent 40 may leak onto tissue 17 surrounding fistula 22 and cause infection or adversely affect healing.

[0052] In some embodiments, the configuration of suction tube 20 and vent tube 18 configures fistula ring 10 as a sump-pump. For example, negative pressure source 62 may continuously draw a negative pressure within sealed inner volume 38, which results in circulation of air when effluent 40 does not reach suction tube 20. When effluent 40 reaches suction tube 20, the negative pressure drawn by negative pressure source 62 is used to suction, draw, or transport effluent 40 out of sealed inner volume 38. Advantageously, the configuration of the suction tube 20 and the vent tube 18 results in the negative pressure through suction tube 20 being used to remove effluent 40 depending on fluid level 43.

[0053] Referring particularly to FIG. 6, first drape 16 may form a sealed inner volume 74. In some embodiments, outer foam ring 14 is positioned within sealed inner volume 74. Sealed inner volume 74 may be independent of sealed inner volume 38. For example, sealed inner volume 74 may be a separate chamber or a separate inner volume from sealed inner volume 38 that does not include sealed inner volume 38. Advantageously, keeping sealed inner volume 74 separate from sealed inner volume 38 facilitates independent application of negative pressure wound therapy through sealed inner volume 74 and independent removal of effluent from fistula 22. In this way, a negative pressure can be drawn at the patient’s periwound tissue 17 through sealed inner volume 74 without drawing a negative pressure at fistula 22. In some embodiments, sealed inner volume 74 is defined by first drape 16, the patient’s periwound tissue 17, and second drape 36.

[0054] Sealed inner volume 74 may define a negative pressure pathway through outer foam ring 14. In some embodiments, first drape 16 includes a negative pressure manifold, a negative pressure port, an opening, an aperture, a window, etc., shown as negative pressure port 57. Negative pressure port 57 is configured to receive a tubular member, a pipe, a conduit, etc., shown as tubular member 58. Tubular member 58 fluidly couples with a negative pressure source, a suction pump, a therapy unit, etc., shown as negative pressure source 60. In some embodiments, negative pressure source 60 is therapy device 602 as described in greater detail below. [0055] Negative pressure source 60 and tubular member 58 can be configured to draw a negative pressure at the patient’s periwound tissue 17 to facilitate healing of the patient’s periwound tissue 17 and fistula 22. In some embodiments, negative pressure source 60 and tubular member 58 are configured to draw the negative pressure at the patient’s periwound tissue 17 through sealed inner volume 74 independently of operation of suction tube 20 and vent tube 18. For example, negative pressure source 60 may draw the negative pressure at sealed inner volume 74 independently of fluid level 43 or independently of pressure within sealed inner volume 38.

[0056] In some embodiments, inner foam ring 12 has a rigidity, resilience, or structural strength that is greater than a rigidity, resilience, or structure strength of outer foam ring 14 so that when negative pressure is drawn at sealed inner volume 74, inner foam ring 12 compresses less than outer foam ring 14. In this way, inner foam ring 12 may maintain its shape or form even under negative pressure.

[0057] Referring particularly to FIG. 7, vent tube 18 may be configured as an instillation tube. In the embodiment shown in FIG. 7, vent tube 18 is fluidly coupled with an instillation source 64 that is configured to provide an instillation fluid to sealed inner volume 38 through vent tube 18. In some embodiments, instillation source 64 includes a reservoir (e.g., a tank, a container, a cartridge, etc.) that stores the instillation fluid. Instillation source 64 can also include a pump for driving the instillation fluid from the reservoir to sealed inner volume 38. In some embodiments, instillation source 64 does not require a pump to drive the instillation fluid if negative pressure source 62 draws a negative pressure or a suction at sealed inner volume 38 that draws instillation fluid into sealed inner volume 38. In some embodiments, instillation source 64 is elevated relative to sealed inner volume 38 so that instillation fluid travels through vent tube 18 to sealed inner volume 38. In some embodiments, instillation source 64 is therapy device 602.

[0058] Advantageously, providing instillation fluid to sealed inner volume 38 can facilitate egress of effluent 40 from sealed inner volume 38 through suction tube 20. For example, if the effluent 40 produced by fistula 22 that enters sealed inner volume 38 (e.g., through bottom lateral opening 54) is thick or very viscous, such effluent 40 may be difficult to remove through suction tube 20. However, the instillation fluid provided to sealed inner volume 38 may reduce the thickness or viscosity of effluent 40, thereby facilitating the removal of effluent 40 through suction tube 20 and reducing a likelihood that effluent 40 will clog in suction tube 20. In some embodiments, the instillation fluid is provided to sealed inner volume 38 continuously and, if fistula 22 is not producing, may be removed from sealed inner volume 38 through suction tube 20. In some embodiments, the instillation fluid is provided intermittently to sealed inner volume 38 as required to achieve a suitable viscosity of effluent 40 for removal of effluent 40 through suction tube 20.

[0059] Advantageously, the fistula ring 10 described herein uses tubes that extend radially outwards or out the side of the fistula ring 10. Configuring the tubes to extend out the side of the fistula ring 10 facilitates a smaller fistula ring 10 that can be positioned between abdominal walls. Conventional fistula devices may use a balloon to collect effluent which may be larger in size or susceptible to breakage. Additionally, such fistula devices may require a caregiver to intermittently check and change or empty the balloon.

[0060] The fistula ring 10 described herein uses suction tube 20 and vent tube 18 so that effluent produced by the fistula is removed from the fistula ring 10. Suction or negative pressure may be provided continuously through the suction tube 20 but only used to remove effluent from fistula ring 10 when a fluid level in fistula ring 10 reaches a specific threshold. Advantageously, removing the effluent from fistula ring 10 facilitates ensuring that the effluent will not leak to periwound tissue and infect the tissue.

[0061] Additionally, the vent tube 18 may be used as an instillation tube to provide instillation fluid to sealed inner volume 38. Advantageously, providing instillation fluid to sealed inner volume 38 facilitates reducing viscosity of effluent produced by the fistula before it is removed from sealed inner volume 38 through suction tube 20. Reducing the viscosity of effluent produced by the fistula may facilitate the egress of the effluent from sealed inner volume 38 through suction tube 20.

[0062] Referring particularly to FIGS. 15 and 16, fistula ring 10 is shown according to another embodiment. Fistula ring 10 may include only inner foam ring 12 instead of inner foam ring 12 and outer foam ring 14. In such an embodiment, inner foam ring 12 may have material properties that are the same as or similar to the material properties of outer foam ring 14. For example, single ring 80 may have a resilience, rigidity, density, or structural strength that is substantially the same as inner foam ring 12 or outer foam ring 14 as described in greater detail above with reference to FIGS. 1-7.

In other embodiments, single ring 80 has a resilience, rigidity, density, or structural strength that is different than inner foam ring 12 and outer foam ring 14 as described in greater detail above with reference to FIGS. 1-7.

[0063] Single foam ring 80 can be covered, coated, etc., with first drape 16 to form a sealed inner volume (e.g., similar to sealed inner volume 74) that does not include inner volume 24 of inner foam ring 12 or sealed inner volume 38. In some embodiments, second drape 36 is configured to cover or seal inner volume 38 independently of sealed inner volume 74 (shown in FIG. 16). First drape 16 may adhere to the patient’s periwound tissue 17 that surrounds fistula 22 and can cover second drape 36. In this way, sealed inner volume 38 may be independent of sealed inner volume 74 so that negative pressure can be drawn at periwound tissue 17 without drawing negative pressure at fistula 22. Advantageously, effluent, exudate, or fluid emitted by fistula 22 into inner volume 24 can be removed from inner volume 24 through suction tube 20. The embodiment of fistula ring 10 shown in FIGS. 15-16 advantageously may achieve the same results as the fistula ring 10 shown in FIGS. 1-6, but only requires inner foam ring 12. It should be understood that outer foam ring 14 may be an optional member or component that can be used to facilitate negative pressure distribution if desired. Process [0064] Referring particularly to FIG. 8, a process 800 for providing a fistula ring or a fistula device is shown, according to some embodiments. Process 800 includes steps 802-820 and may be performed by a caregiver or a nurse when setting up fistula ring 10 for use. It should be understood that the various components of fistula ring 10 as described herein may be provided to a caregiver in a kit, which may include all of the components of fistula ring 10 in a disassembled or partially assembled state.

[0065] Process 800 includes providing a fistula ring including an inner ring member and an outer ring member (step 802), according to some embodiments. In some embodiments, the inner ring member is inner foam ring 12 and the outer ring member is outer foam ring 14. The inner ring member and the outer ring member may be configured or shaped so that the inner ring member can be positioned within the outer ring member. The inner ring member and the outer ring member may be provided in a kit that includes the various components of the fistula ring.

[0066] Process 800 includes providing or defining a first sealed inner volume by adhering a drape layer around the inner ring member and one lateral end of the inner ring member (step 804), according to some embodiments. In some embodiments, the drape layer is second drape 36. The drape layer may be provided to a caregiver in the kit for the fistula ring. The drape layer may wrap around an outer surface or outer periphery of the inner ring member and seal one lateral end of the inner ring member, while leaving an opposite lateral end of the ring member open.

[0067] Process 800 includes positioning the inner ring member within the outer ring member (step 806), according to some embodiments. The inner ring member may have a shape that corresponds to a shape of the outer ring member so that the inner ring member can be positioned within the outer ring member. The outer surface of the inner ring member may abut, contact, engage, etc., an interior surface of the outer ring member when the inner ring member is positioned within the outer ring member.

[0068] Process 800 includes providing a first opening and a second opening through a side of the inner ring member and the outer ring member (step 808), according to some embodiments. The first opening may be opening 76 and the second opening may be opening 78. The first opening may be positioned longitudinally above the second opening or vice versa. The first opening and the second opening may be provided by a caregiver by making an incision through a side of the inner ring member and the outer ring member. In some embodiments, the first opening and the second opening are provided through a side of the inner ring member only, and not the outer ring member.

[0069] Process 800 includes providing an adhesive member to a bottom lateral surface of the inner ring member (step 810), according to some embodiments. The adhesive member may be adhesive member 34 and can be applied to the bottom lateral surface of the inner ring member which is proximate the lateral opening of the inner ring member.

[0070] Process 800 includes providing a first tube through the first opening and a second tube through the second opening to fluidly couple with the first sealed inner volume (step 812), according to some embodiments. The first tube may be suction tube 20 while the second tube may be vent tube 18. If the first opening and the second opening extend only through the side of the inner ring member, the first tube and the second tube may extend through the inner ring member and between the outer surface of the inner ring and the inner surface of the outer ring member.

[0071] Process 800 includes positioning the inner and outer ring members over a fistula so that effluent produced by the fistula enters the first sealed inner volume through a bottom lateral opening of the inner ring member (step 814), according to some embodiments. The fistula may produce or emit effluent which may enter the first sealed inner volume and then be transported out of the first sealed inner volume through one of the first or second tubes. The inner ring member may sealingly couple with tissue that surrounds the fistula through the adhesive member so that effluent does not leak out of the first sealed inner volume.

[0072] Process 800 includes providing a drape layer over the inner and outer ring members to define a second sealed inner volume that is independent or separate from the first sealed inner volume (step 816), according to some embodiments. The drape layer may enclose and cover the inner and outer ring members and define the second sealed inner volume for negative pressure application to tissue surrounding the fistula.

[0073] Process 800 includes providing an opening in the drape layer (step 818) and fluidly coupling a therapy unit with the second sealed inner volume through the opening in the drape layer (step 820), according to some embodiments. The opening may be provided through the drape layer so that the therapy unit can be fluidly coupled with the second sealed inner volume through a tubular member. The therapy unit may be operated to draw a negative pressure at the second sealed inner volume, independently of the first sealed inner volume.

[0074] Referring particularly to FIG. 9, a process 900 for using the fistula ring provided in process 800 is shown, according to some embodiments. Process 900 includes steps 902-912 and can be performed to remove effluent from the first sealed inner volume of the fistula ring.

[0075] Process 900 includes providing a fistula ring according to process 800 (step 902), according to some embodiments. Step 902 may be performed by a caregiver using a kit that includes the various components of the fistula ring.

[0076] Process 900 includes drawing a negative pressure at the first sealed inner volume through the first tube (step 904), according to some embodiments. The first tube may be fluidly coupled with a negative pressure source such as wall pressure (e.g., a wall negative pressure source such as from a building suction source accessible in a treatment room from a wall-mounted valve, fitting, or the like), a therapy unit, a suction pump, a continuous negative pressure source, an adjustable negative pressure source, etc.

[0077] Process 900 includes venting the second tube to atmospheric pressure (step 906), according to some embodiments. The second tube may fluidly couple with the first sealed inner volume at a first end, and vented to atmospheric pressure at a second or distal end. An air filter may be used to ensure that any air that enters the first sealed inner volume is free of contaminants.

[0078] Process 900 includes drawing a negative pressure at the second sealed inner volume (step 908), according to some embodiments. The negative pressure may be drawn by operating a therapy unit. The therapy unit may be fluidly coupled with the second sealed inner volume through a tubular member and the opening produced in step 818 of process 800.

[0079] Process 900 includes removing effluent from the first sealed inner volume through the first tube (step 910), according to some embodiments. The effluent may be removed through the first tube due to the negative pressure drawn at the first sealed inner volume. The effluent may be removed when the effluent builds up in the first sealed inner volume such that the effluent reaches the first tube.

[0080] Process 900 includes providing instillation fluid to the first sealed inner volume through the second tube (step 912), according to some embodiments. Step 912 may be optional. The second tube may be fluidly coupled with an instillation source (e.g., a pump and reservoir). The instillation source may be configured to actively provide instillation fluid to the first sealed inner volume (e.g., using a pump) or may passively provide instillation fluid to the first sealed inner volume (e.g., instillation fluid may enter the first sealed inner volume due to the negative pressure drawn at the first sealed inner volume via the first tube). Providing instillation fluid may reduce a viscosity of the effluent and facilitate removal of the effluent from the first sealed inner volume.

[0081] Referring particularly to FIG. 14, a process 1000 for treating a fistula is shown, according to some embodiments. Process 1000 includes steps 1010 and can be performed using fistula ring 10. Process 1000 can facilitate healing progress of a fistula by removing effluent from the fistula.

[0082] Process 1000 includes placing a ring member around a fistula (step 1002), according to some embodiments. The ring member may be fistula ring 10. The ring member may sealingly couple with tissue surrounding the fistula and can include a closed inner volume. The ring member may include a top side, a bottom, side, and a sidewall. The ring member can also include a first tube and a second tube extending through the sidewall.

[0083] Process 1000 includes covering the ring member with a drape (step 1004), according to some embodiments. The drape may be first drape 16 and can at least partially define a closed inner volume over the fistula (e.g., sealed inner volume 38). The drape may adhere to tissue surrounding the fistula or tissue surrounding the ring member.

[0084] Process 1000 includes venting the closed inner volume to the atmosphere through the second tube (step 1006), according to some embodiments. The second tube may be vent tube 18 and can include a first end that is fluidly coupled with or terminates at the closed inner volume and a second or distal end that is vented to atmospheric pressure or the atmosphere.

[0085] Process 1000 includes drawing a suction at the inner volume through a suction tube (step 1008), according to some embodiments. The suction tube may be the first tube. The suction tube may be fluidly coupled with a negative pressure or a suction source that is configured to draw a suction at the inner volume.

[0086] Process 1000 includes suctioning fistula effluent from the inner volume through the suction tube (step 1010), according to some embodiments. The fistula effluent may be suctioned from the inner volume through the suction tube only when the fistula effluent reaches the suction tube.

Wound Therapy System

[0087] Referring now to FIGS. 10-13, a negative pressure wound therapy (NPWT) system 600 is shown, according to an exemplary embodiment. NPWT system 600 is shown to include a therapy device 602 fluidly connected to a wound dressing 100 via tubing 608 and 610. Wound dressing 100 may be adhered or sealed to a patient’s skin 102 surrounding a wound 122. Several examples of wound dressings 100 which can be used in combination with NPWT system 600 are described in detail in U.S. Patent No. 7,651,484 granted January 26, 2010; U.S. Patent No. 8,394,081 granted March 12, 2013; and U.S. Patent Application No. 14/087,418 filed November 22, 2013, now U.S. Patent No. 10,232,155 granted March 19, 2019. The entire disclosure of each of these patents and patent applications is incorporated by reference herein.

[0088] It should be understood that while therapy device 602 as described herein is configured for use with a wound dressing 100 and a wound 122, therapy device 602 may be configured for use with fistula ring 10. For example, tubing 608 may be vent tube 18 and tubing 610 may be suction tube 20 such that therapy device 602 functions as instillation source 64 and negative pressure source 62 as described in greater detail above. In some embodiments, therapy device 602 can be configured to provide negative pressure to sealed inner volume 74 through tubular member 58. Therapy device 602 can also be configured to provide instillation fluid to sealed inner volume 74 through tubing 608. For example, first drape 16 may include another opening similar to negative pressure port 57 that is configured to receive tubing 608 so that instillation fluid may be provided to sealed inner volume 74. In this way, therapy device 602 may function as negative pressure source 60.

[0089] Therapy device 602 can be configured to provide negative pressure wound therapy by reducing the pressure at wound 122. Therapy device 602 can draw a vacuum at wound 122 (relative to atmospheric pressure) by removing wound exudate, air, and other fluids from wound 122. Wound exudate may include fluid that filters from a patient’s circulatory system into lesions or areas of inflammation. For example, wound exudate may include water and dissolved solutes such as blood, plasma proteins, white blood cells, platelets, and red blood cells. Other fluids removed from wound 122 may include instillation fluid 605 previously delivered to wound 122. Instillation fluid 605 can include, for example, a cleansing fluid, a prescribed fluid, a medicated fluid, an antibiotic fluid, or any other type of fluid which can be delivered to wound 122 during wound treatment. Instillation fluid 605 may be held in an instillation fluid canister 604 and controllably dispensed to wound 122 via instillation fluid tubing 608. In some embodiments, instillation fluid canister 604 is detachable from therapy device 602 to allow canister 606 to be refilled and replaced as needed. [0090] The fluids 607 removed from wound 122 pass through removed fluid tubing 610 and are collected in removed fluid canister 606. Removed fluid canister 606 may be a component of therapy device 602 configured to collect wound exudate and other fluids 607 removed from wound 122. In some embodiments, removed fluid canister 606 is detachable from therapy device 602 to allow canister 606 to be emptied and replaced as needed. A lower portion of canister 606 may be filled with wound exudate and other fluids 607 removed from wound 122, whereas an upper portion of canister 606 may be filled with air. Therapy device 602 can be configured to draw a vacuum within canister 606 by pumping air out of canister 606. The reduced pressure within canister 606 can be translated to wound dressing 100 and wound 122 via tubing 610 such that wound dressing 100 and wound 122 are maintained at the same pressure as canister 606.

[0091] Referring particularly to FIGS. 11-13, block diagrams illustrating therapy device 602 in greater detail are shown, according to an exemplary embodiment. Therapy device 602 is shown to include a pneumatic pump 620, an instillation pump 622, a valve 632, a filter 628, and a controller 618. Pneumatic pump 620 can be fluidly coupled to removed fluid canister 606 (e.g., via conduit 636) and can be configured to draw a vacuum within canister 606 by pumping air out of canister 606. In some embodiments, pneumatic pump 620 is configured to operate in both a forward direction and a reverse direction. For example, pneumatic pump 620 can operate in the forward direction to pump air out of canister 606 and decrease the pressure within canister 606. Pneumatic pump 620 can operate in the reverse direction to pump air into canister 606 and increase the pressure within canister 606. Pneumatic pump 620 can be controlled by controller 618, described in greater detail below.

[0092] Similarly, instillation pump 622 can be fluidly coupled to instillation fluid canister 604 via tubing 609 and fluidly coupled to wound dressing 100 via tubing 608. Instillation pump 622 can be operated to deliver instillation fluid 605 to wound dressing 100 and wound 122 by pumping instillation fluid 605 through tubing 609 and tubing 608, as shown in FIG. 4. Instillation pump 622 can be controlled by controller 618, described in greater detail below.

[0093] Filter 628 can be positioned between removed fluid canister 606 and pneumatic pump 620 (e.g., along conduit 636) such that the air pumped out of canister 606 passes through fdter 628. Filter 628 can be configured to prevent liquid or solid particles from entering conduit 636 and reaching pneumatic pump 620. Filter 628 may include, for example, a bacterial filter that is hydrophobic and/or lipophilic such that aqueous and/or oily liquids will bead on the surface of filter 628.

Pneumatic pump 620 can be configured to provide sufficient airflow through filter 628 that the pressure drop across filter 628 is not substantial (e.g., such that the pressure drop will not substantially interfere with the application of negative pressure to wound 122 from therapy device 602).

[0094] In some embodiments, therapy device 602 operates a valve 632 to controllably vent the negative pressure circuit, as shown in FIG. 12A. Valve 632 can be fluidly connected with pneumatic pump 620 and filter 628 via conduit 636. In some embodiments, valve 632 is configured to control airflow between conduit 636 and the environment around therapy device 602. For example, valve 632 can be opened to allow airflow into conduit 636 via vent 634 and conduit 638, and closed to prevent airflow into conduit 636 via vent 634 and conduit 638. Valve 632 can be opened and closed by controller 618, described in greater detail below. When valve 632 is closed, pneumatic pump 620 can draw a vacuum within a negative pressure circuit by causing airflow through fdter 628 in a first direction, as shown in FIG. 11. The negative pressure circuit may include any component of system 600 that can be maintained at a negative pressure when performing negative pressure wound therapy (e.g., conduit 636, removed fluid canister 606, tubing 610, wound dressing 100, and/or wound 122). For example, the negative pressure circuit may include conduit 636, removed fluid canister 606, tubing 610, wound dressing 100, and/or wound 122. When valve 632 is open, airflow from the environment around therapy device 602 may enter conduit 636 via vent 634 and conduit 638 and fill the vacuum within the negative pressure circuit. The airflow from conduit 636 into canister 606 and other volumes within the negative pressure circuit may pass through filter 628 in a second direction, opposite the first direction, as shown in FIG. 12A.

[0095] In some embodiments, therapy device 602 vents the negative pressure circuit via an orifice 158, as shown in FIG. 12B. Orifice 158 may be a small opening in conduit 636 or any other component of the negative pressure circuit (e.g., removed fluid canister 606, tubing 610, tubing 611, wound dressing 100, etc.) and may allow air to leak into the negative pressure circuit at a known rate. In some embodiments, therapy device 602 vents the negative pressure circuit via orifice 158 rather than operating valve 632. Valve 632 can be omitted from therapy device 602 for any embodiment in which orifice 158 is included. The rate at which air leaks into the negative pressure circuit via orifice 158 may be substantially constant or may vary as a function of the negative pressure, depending on the geometry of orifice 158.

[0096] In some embodiments, therapy device 602 includes a variety of sensors. For example, therapy device 602 is shown to include a pressure sensor 630 configured to measure the pressure within canister 606 and/or the pressure at wound dressing 100 or wound 122. In some embodiments, therapy device 602 includes a pressure sensor 613 configured to measure the pressure within tubing 611. Tubing 611 may be connected to wound dressing 100 and may be dedicated to measuring the pressure at wound dressing 100 or wound 122 without having a secondary function such as channeling installation fluid 605 or wound exudate. In various embodiments, tubing 608, 610, and 611 may be physically separate tubes or separate lumens within a single tube that connects therapy device 602 to wound dressing 100. Accordingly, tubing 610 may be described as a negative pressure lumen that functions apply negative pressure wound dressing 100 or wound 122, whereas tubing 611 may be described as a sensing lumen configured to sense the pressure at wound dressing 100 or wound 122. Pressure sensors 630 and 613 can be located within therapy device 602, positioned at any location along tubing 608, 610, and 611, or located at wound dressing 100 in various embodiments. Pressure measurements recorded by pressure sensors 630 and/or 613 can be communicated to controller 618. Controller 618 use the pressure measurements as inputs to various pressure testing operations and control operations performed by controller 618.

[0097] Controller 618 can be configured to operate pneumatic pump 620, instillation pump 622, valve 632, and/or other controllable components of therapy device 602. In some embodiments, controller 618 operates pneumatic pump 620, instillation pump 622, valve 632, and/or other controllable components of therapy device 602 to draw a negative pressure at wound 122 and/or to provide instillation fluid to wound 122.

[0098] In some embodiments, therapy device 602 includes a user interface 626. User interface 626 may include one or more buttons, dials, sliders, keys, or other input devices configured to receive input from a user. User interface 626 may also include one or more display devices (e.g., UEDs, UCD displays, etc.), speakers, tactile feedback devices, or other output devices configured to provide information to a user. In some embodiments, the pressure measurements recorded by pressure sensors 630 and/or 613 are presented to a user via user interface 626. User interface 626 can also display alerts generated by controller 618. For example, controller 618 can generate a “no canister” alert if canister 606 is not detected.

[0099] In some embodiments, therapy device 602 includes a data communications interface 624 (e.g., a USB port, a wireless transceiver, etc.) configured to receive and transmit data.

Communications interface 624 may include wired or wireless communications interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wire terminals, etc.) for conducting data communications external systems or devices. In various embodiments, the communications may be direct (e.g., local wired or wireless communications) or via a communications network (e.g., a WAN, the Internet, a cellular network, etc.). For example, communications interface 624 can include a USB port or an Ethernet card and port for sending and receiving data via an Ethernet-based communications link or network. In another example, communications interface 624 can include a Wi-Fi transceiver for communicating via a wireless communications network or cellular or mobile phone communications transceivers.

Configuration of Exemplary Embodiments

[0100] As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims. [0101] It should be noted that the term “exemplary” and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0102] The term “coupled,” as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using a separate intervening member and any additional intermediate members coupled with one another, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. Such members may be coupled mechanically, electrically, and/or fluidly.

[0103] References herein to the positions of elements (e.g., “top,” “bottom,” “above,” “below,” etc.) are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

[0104] The hydrophobicity of a material may vary, but to be considered hydrophobic, generally the material can have an average contact angle with water of at least 90 degrees in some embodiments.

To be considered hydrophilic, generally the material can have a contact angle of most 90 degrees in some embodiments. In some embodiments the contact angle with water can be no more than 150 degrees. For example, in some embodiments, the contact angle of the hydrophobic material may be in a range of at least 70 degrees to about 120 degrees with an average contact angle of at least 90 degrees, or in a range of at least 120 degrees to 150 degrees. Water contact angles can be measured using any standard apparatus. Although manual goniometers can be used to visually approximate contact angles, contact angle measuring instruments can often include an integrated system involving a level stage, liquid dropper such as a syringe, camera, and software designed to calculate contact angles more accurately and precisely, among other things. Non-limiting examples of such integrated systems may include the FTA125, FTA200, FTA2000, and FTA4000 systems, all commercially available from First Ten Angstroms, Inc., of Portsmouth, Va., and the DTA25, DTA30, and DTA100 systems, all commercially available from Kruss GmbH of Hamburg, Germany. Unless otherwise specified, water contact angles herein are measured using deionized and distilled water on a level sample surface for a sessile drop added from a height of no more than 5 cm in air at 20-25° C and 20- 50% relative humidity. Contact angles reported herein represent averages of 5-9 measured values, discarding both the highest and lowest measured values. The hydrophobicity of a material herein may be further enhanced with a hydrophobic coating of other materials, such as silicones and fluorocarbons, and by any means known, such as by coating by the other material (e.g., coated using a liquid that may be subsequently dried on the material) or plasma coated.

[0105] A hydrophobic material can be any material having a solubility in water of less than 10 mg/U at standard temperature and pressure. A hydrophilic material can be any material having a solubility in water of 10 mg/U and greater at standard temperature and pressure. [0106] It is important to note that the construction and arrangement of the wound dressing with optional status indicator as shown in the various exemplary embodiments is illustrative only.

Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.). For example, the position of elements may be reversed or otherwise varied and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present disclosure.

[0107] Additionally, any element disclosed in one embodiment may be incorporated or utilized with any other embodiment disclosed herein. For example, the configuration and construction of fistula ring 10 of the exemplary embodiment described in at least paragraph [0045] may be incorporated in the fistula ring 10 of the exemplary embodiment described in at least paragraph

[0049] . Although only one example of an element from one embodiment that can be incorporated or utilized in another embodiment has been described above, it should be appreciated that other elements of the various embodiments may be incorporated or utilized with any of the other embodiments disclosed herein.

Claims

WHAT IS CLAIMED IS:

1. A fistula device for suctioning effluent emitted by a fistula, the device comprising: an outer ring member comprising an interior surface and an exterior surface positioned a first wall thickness apart; an inner ring member positioned within the outer ring member and comprising an interior surface and an exterior surface positioned a second wall thickness apart, the inner ring member defining a sealed inner volume in fluidic communication with a fistula, wherein the inner ring member and the outer ring member are centered about a common axis; and a first tubular member in fluidic communication with the sealed inner volume and fluidly coupled with a first negative pressure source to draw a negative pressure within the sealed inner volume; wherein the first tubular member is configured to transport effluent emitted by the fistula into the sealed inner volume out of the sealed inner volume.

2. The fistula device of Claim 1, further comprising a second tubular member in fluidic communication with the sealed inner volume, wherein the second tubular member is positioned a distance from the fistula along the common axis that is a greater than a distance between the first tubular member and the fistula along the common axis.

3. The fistula device of Claim 2, wherein the second tubular member is vented to atmospheric pressure.

4. The fistula device of Claim 3, wherein air introduced to the sealed inner volume through the second tubular member is drawn out of the sealed inner volume through the first tubular member when a fluid level of effluent emitted by the fistula does not reach the first tubular member.

5. The fistula device of Claim 4, wherein the first tubular member and the first negative pressure source are configured to transport effluent emitted by the fistula out of the sealed inner volume when the fluid level of effluent emitted by the fistula reaches the first tubular member.

6. The fistula device of Claim 2, wherein the second tubular member is fluidly coupled with an instillation source, wherein the second tubular member is configured to provide an instillation fluid from the instillation source to the sealed inner volume.

7. The fistula device of Claim 1, further comprising a first drape member, wherein the first drape member is configured to seal with tissue surrounding the fistula and the outer ring member, wherein the first drape member covers the outer ring member, the inner ring member, and the first tubular member.

8. The fistula device of Claim 7, wherein the first drape member further comprises a negative pressure interface, wherein the negative pressure interface is configured to fluidly couple with a second negative pressure source to draw a negative pressure at tissue surrounding the fistula through the outer ring member.

9. The fistula device of Claim 7, further comprising a second drape member, wherein the second drape member is configured to extend along the exterior surface of the inner ring member and a top lateral opening of the inner ring member to define the sealed inner volume.

10. The fistula device of Claim 1, wherein the inner ring member is configured to seal with tissue surrounding the fistula.

11. The fistula device of Claim 10, further comprising an adhesive member positioned between a bottom lateral surface and the tissue surrounding the fistula, wherein the adhesive member is configured to sealingly couple the bottom lateral surface of the inner ring member with the tissue surrounding the fistula.

12. The fistula device of Claim 1, wherein the outer ring member and the inner ring member are foam members.

13. The fistula device of Claim 12, wherein the inner ring member has a resilience that is higher than a resilience of the outer ring member.

14. The fistula device of Claim 1, wherein the outer ring member and the inner ring member are circular shaped.

15. A fistula dressing comprising: an inner ring member and an outer ring member, wherein the inner ring member is positioned within the outer ring member and defines a first inner volume that is fluidly coupled with a fistula; a first tubular member and a second tubular member extending through a side of the inner ring member and the outer ring member to the first inner volume, wherein at least one of the first tubular member or the second tubular member are fluidly coupled with a first negative pressure source to draw effluent emitted by the fistula out of the first inner volume.

16. The fistula dressing of Claim 15, wherein the first tubular member is positioned closed to the fistula than the second tubular member, and is fluidly coupled with the negative pressure source.

17. The fistula dressing of Claim 16, wherein the second tubular member is vented to atmospheric pressure.

18. The fistula dressing of Claim 16, wherein the second tubular member is fluidly coupled with an instillation source, wherein the second tubular member and the instillation source are configured to provide an instillation fluid to the first inner volume.

19. The fistula dressing of Claim 15, wherein a lateral end of the inner ring member that is distal from the fistula is sealed and a lateral end of the inner ring member that is proximate the fistula is open so that the first inner volume is fluidly coupled with the fistula.

20. The fistula dressing of Claim 19, further comprising: a first drape extending along an outer surface of the inner ring member and the lateral end that is distal from the fistula to define the first inner volume; a second drape extending over the inner ring member, the outer ring member, the first drape, the first tubular member, the second tubular member, and the first inner volume, wherein the second drape seals with tissue surrounding the fistula and defines a second inner volume.

21. The fistula dressing of Claim 20, wherein the first inner volume and the second inner volume are independent of each other.

22. The fistula dressing of Claim 20, wherein the second drape comprises a negative pressure port, wherein the negative pressure port is configured to fluidly couple with a tubular member and a second negative pressure source to draw a negative pressure at the second inner volume, independently of the first negative pressure source.

23. A fistula device for suctioning effluent emitted from a fistula, comprising: a ring member having a top side, a bottom side configured for placement on a patient about a fistula, and a sidewall; a drape layer extending over the top side of the ring and having a wing portion sealable to a patient outside the sidewall, wherein the drape layer and sidewall define a closed inner volume when placed over the fistula; a first tube extending through the sidewall and having a first end communicating with the inner volume and a second end configured to engage a suction source; a second tube extending through the sidewall and having a first end communicating with the inner volume and a second end configured to selectively engage an irrigation fluid source and an air supply source.

24. The fistula device of Claim 23, further comprising an adhesive on the bottom side of the ring member.

25. The fistula device of Claim 23, wherein the ring member is conformable to different shapes.

26. A method of treating a fistula, comprising: placing a ring member around a fistula, the ring member having a top side, a bottom side, and a sidewall, and a first tube and a second tube extending through the sidewall; covering the ring member with a drape to define a closed inner volume over the fistula; venting the closed inner volume to atmosphere through the second tube; drawing suction on the inner volume through the first tube; and suctioning a fistula effluent from the inner volume through the first tube when fistula effluent reaches the first tube.

27. A method of treating an unexposed fistula located beneath an abdominal wall, comprising: assembling a low profile fistula device having at least one ring member defining an inner volume with a first tube and a second tube extending through a sidewall of the ring and communicating with the inner volume; sliding the fistula device beneath the abdominal wall so that the ring surrounds the fistula; maintaining atmospheric pressure at the inner volume by venting the inner volume through the first tube; and removing effluent emitted by the fistula into the inner volume by suctioning the effluent through the second tube.

28. The method of Claim 27, wherein the first tube and the second tube extend radially outwards through the sidewall of the ring and fluidly communicate with the inner volume.