FR3126185A1 - PROTECTION DEVICE SUITABLE FOR PREVENTING A SURFACE, SUCH AS THE SKIN, FROM SUPPORTING ANY EXTERNAL STRESS AND THUS PREVENTING PRESSURE NUTS - Google Patents

Abstract

The present invention relates to a device for protecting a predetermined surface (9) capable of preventing it from supporting any external stresses, such that it comprises: - a first rigid part (8), called a concentrator, capable of support said external stresses and whose projection surface on the surface (9), perpendicular to the latter, at least equal to said surface (9) to be protected, - at least one second part (10) having a deformable part and called transmitter, supporting and blocking at least radially the concentrator (8), and said transmitter receiving the forces resulting from the stresses exerted on the concentrator (8) maintains the latter at a minimum height (h) above said surface to be protected (9), when the concentrator (8) transmits said forces to it, and - at least a third part (11), called effector, capable of being placed against a so-called external support surface (3), surrounding at least the surface (9) to be protected without covering it, and capable of taking charge of the forces that the concentrator (8) transmits to it by the transmitter (10) to distribute them in pressure exerted on said support surface (3 ) external. Figure for abstract: 1

Description

PROTECTIVE DEVICE CAPABLE OF PREVENTING A SURFACE, SUCH AS THE SKIN, FROM SUPPORTING ANY EXTERNAL CONSTRAINTS AND THUS PREVENTING PRESSURE SORES

Technical field of the invention

The present invention relates to a device for protecting a predetermined surface capable of preventing it from supporting any external stresses, such as pressure and shear.

The invention relates more particularly to a protective device capable of being placed on a part of a patient's skin to prevent and protect it against bedsores but the use of the device according to the invention can be broader and adapted for the protection not only of any biological surface such as the skin, and such as for example to be worn by motorists, or adapted to a motorcycle saddle, or even used as comfort clothing to relieve certain areas of the body or even for the skin of animals, but also of any non-biological surface.

Technical background

For the main application of the invention, bedsores are wounds occurring in weakened people following compression of the tissues in areas where the underlying bones are flush. This compression causes a process of reduction or cessation of blood flow in the capillary vessels called ischemia. Tissue hypoxia then occurs within one to two hours and the pressure sore sets in, first in the form of redness (persistent erythema, stage 1) which will progress to the appearance of more or less deep wounds, which can become purulent, and lead to tissue necrosis.

The intensity, duration and pressure gradient favor pressure sores. The higher the pressure, the faster the pressure sore forms.

All it takes is strong and/or prolonged compression exerted on the tissues between the bony protrusions and a more or less hard plane to cause a reduction in capillary blood flow – a phenomenon known as ischemia. Indeed when the pressure exerted on the capillaries approaches the internal pressure of the blood flow of around 32 mmHg then they close and the oxygen supply decreases leading to tissue hypoxia and an alteration of the skin tissues called bedsores. - from the Greek echara “crust”. The bedsore is also called pressure ulcer or decubitus ulcer (terminology adopted by the Anglo-Saxons: pressure ulcer, decubitus ulcer).

A certain number of impacting factors are at the origin of the occurrence of pressure sores, and can contribute to worsening or reducing them. We distinguish between exogenous factors and endogenous factors.

Exogenous factors directly cause the occurrence of pressure sores when the physiological terrain is favorable: they are linked to the interaction between the patient and his environment and are mechanical in nature (shear pressure and friction) with possibly local aggravating factors such as maceration. – due for example for pelvic bedsores to urine and stools.

Endogenous factors are those which favor the physiological environment conducive to the occurrence of bedsores. They are intrinsic or clinical in nature – including: immobility, age, nutritional status, skin condition, incontinence, pathology weakening the body, dehydration, etc.

The risks of morbidity are multiplied by 3 to 5 for the elderly in the event of pressure sores. A low estimate of the number of deaths due to pressure sores is 14,000 per year in France.

Pressure sores mainly occur in the pelvic region – sacrum, trochanter and ischium – and the foot region – heels and malleolus. Other regions of the body are also affected but more marginally – occiput, shoulders, etc.

Pressure ulcer prevention and treatment strategies recommended by national and international health authorities are recorded in good practice guides – notably the Prevention and Treatment of Pressure Ulcers: Quick Reference Guide co-established by the National Pressure Ulcer Advisory Panel (USA) , European Pressure Ulcer Advisory Panel (EU) and the Pan Pacific Pressure Injury Alliance, the JSPU Guidelines for the Prevention and Management of Pressure Ulcers for Japan or even for France the Recommendations formulated at the end of the Consensus Conference “Prevention and treatment of pressure sores in adults and the elderly” in 2001.

Sophisticated care protocols are put in place combining the use of medical relief devices, a pharmacopoeia adapted to the stage of severity, and frequent changes in patient positions carried out by nursing staff. Thus a recent statistical study showed a strong correlation between the frequency of repositioning and the incidence of pressure sores: incidence of 8% for repositioning carried out every 2–3 hours, compared to 13% for a cycle of 4–6 hours. .

A defect in the protocol – incorrect positioning on the devices, ineffective device, late application of care, etc. – and the condition of the skin deteriorates quickly. First in the form of desepidermization (superficial abrasion) or the appearance of a blistering intact or not (stage 2) which if not treated quickly transforms into ulceration of the entire thickness of the skin , with damage to the subcutaneous tissues that can extend to the muscle without damaging it (stage 3). In the absence of effective and heavy treatment, we progress towards a loss of all tissue layers with exposure of muscle, tendon, and/or bone (stage 4).

Since pressure is one of the main causes of bedsores, all current prevention strategies converge towards the need to relieve pressure, through the choice of viscoelastic materials or by hollowing out the devices (mattress, cushions, etc.). wedges) to the right of the areas at risk of developing a pressure sore, or to the right of the declared pressure sore.

But the discharge does not prevent the risk of shearing which remains. However, taking shear forces into account is all the more fundamental, as they represent 3 times more danger of pressure ulcers than pressure forces.

As continuous assistance to patients is not possible and patients move, even those not suffering from neuronal disturbances, inevitably displacements of bedsores in the bordering zones occur due to poor positioning, changes in the position of the patients between two interventions by healthcare personnel, a transfer of pressure, or prolonged contact with an element of the bed such as the protection bars or even the fold of a sheet.

As mentioned previously, prevention strategies all agree on the recommendation of care protocols incorporating regular repositioning/turning of the patient to relieve areas under pressure. Thus in France, it is recommended to change position every 2 or 3 hours, to be adapted to the patient's context.

This proves difficult to implement both in terms of mobilizing healthcare staff and the consequences for these staff. In fact, this leads to various musculoskeletal pathologies in the latter, and especially chronic lower back pain, which is the cause of the majority of occupational disorders and half of work accidents in the health sector.

Furthermore, if regular change of position proves to be an effective contribution to the prevention and support of the treatment of pressure sores, this practice is impossible for people at the end of life, patients in orthopedic traction, severe burn victims, people confined to immobility – particularly for people in intensive care, or people suffering from neurological pathologies or who are regularly agitated.

The majority of solutions offered are supports – mattresses, cushions, wedges – made from structured or raw materials designed to reduce pressure. It is therefore not surprising to find numerous patents for anti-decubitus devices based on the recess of the supports in areas at risk of decubitus in order to eliminate the load: in this area we can cite the patent application PCT WO2018/038402 from the Korean company One For All teaching a mattress-type support, for a patient lying down in order to prevent decubitus ulcers, which constitute a very common case of bedsores reported in the patent literature for people having to remain immobile in lying position; the support described in this PCT patent application is composed of a plurality of cushioning layers having a body pressure distribution mechanism and through-holes formed in each cushioning layer, the size of the through-hole formed in an upper cushioning layer being smaller than the size of the hole passing through the adjacent lower cushioning layer so as to be in communication with each other.

But this assumes that the patient is well positioned on such a support and does not move.

Other solutions are based on the motorization of an alternating inflation/deflation cycle of modules constituting the support. These are only recommended for severe cases and severely immobilized patients. In the event of a motor failure, a bedsore can occur within two hours.

Moreover :
- for bedsores of the heel and foot in general, as well as for the protection of wounds on the arch of the foot, there are suitable devices, which are still the subject of numerous patents filed such as Chinese patent application CN211932856 published in 2020 by Zhongnan Hospital of Wuhan University which describes a decompression cushion held on the foot by a toe sleeve and a fixing band surrounding the ankle, the body of this decompression cushion also being fixedly connected to a heel cushion and comprising at least one opening at the site of the wound, a sponge cushion which can be placed in the cavity with silica gel in order to provide a certain comfort to the patient,
- for pressure sores of the sacrum, a decubitus wedge has been specifically developed, a foam cylinder with a triangular section the length of the mattress which allows the patient to be wedged in a lateral position at 45°, then on the other side always at 45° ° after change of position by the nursing staff. A trend noted in the analysis of recent patent filings relating to anti-decubitus mattresses (see example of the PCT patent cited above) is to achieve a more pronounced central relief obtained by simple or multiple recess, by use of single or multi-layer foam lower resistance to compression – which again poses the problem of correct positioning of the patient – morphology, size, compatibility with sitting position, forward slide, etc.

However, as discussed by professionals from the “Société Française de l’Escarre” during a webinar in February 2021, no satisfactory solution for carrying out discharge exists to date. In addition to pressure sores of the sacrum, another problem is added for people suffering from incontinence or who are placed in a diaper to prevent leakage. These are the risks of maceration increased by urine and the risks of contamination by stools which weaken the skin and which, in the event of a wound, will contaminate it and darken the prognosis of progression of the bedsore.

Finally, when the bedsore has progressed to a stage presenting high morbidity risks, there is a final heavy technique to implement, called "negative pressure". For this, a specially made dressing is connected to a source of depression and to an exudate collection system. The Haute Autorité de Santé recommends limiting its use only to wounds resistant to well-conducted general and local treatment, with a view to surgical coverage (graft or flap). It also recommends stopping treatment if there is no improvement after two consecutive dressing changes or after two weeks of use.

The average prevalence of bedsores in France - that is to say the percentage of people hospitalized suffering from bedsores - is estimated at 8.6%, while its incidence - that is to say the percentage of people whose bedsore started while they were hospitalized for another reason - is 4.3%. Estimates for France are 300,000 bedsores per year occurring in hospitals or nursing homes, and 150,000 for patients hospitalized at home: and the morbidity rate in France is estimated as previously indicated at 14,000 deaths per year. but this is certainly a reduction because for example for a patient who dies following infection from a bedsore but had been hospitalized for another pathology, it is generally the latter which will be retained as the cause of death.

In terms of economic issues in France, the annual cost of treating pressure sores is 3.35 billion euros, or nearly 2% of total health spending. It is estimated, depending on the studies and the reference country, that the cost of hospital treatment of a pressure sore generally varies between 15,000 euros to 50,000 euros per year and per patient, a cost that can reach 150,000 euros for stage 4 pressure sores.

This is therefore a major health issue for which significant developments are expected to offer effective prevention and treatment solutions which respond to the weaknesses of existing devices which offer partial discharge, and an effectiveness which depends on the positioning of the patient. on the support and requires a large number of repositionings carried out every day by the nursing staff.

The global pressure ulcer market represents several million affected patients each year and there is regular annual growth. In 2021, for the United States, it is estimated that pressure sores will affect 3 million people and the annual cost to the health system is estimated at $25 billion.

The problem posed is thus to create a protection device which at the same time makes it possible to:
- eliminate any contact on the surface to be protected, such as the skin, and the effects of external stresses such as friction, shear and pressure, not only in areas at risk of bedsores but also in peripheral areas to risk of pressure sore displacement, and
- remain independent of the position adopted by the patient, while reducing the need to change position to the strict comfort of the patients.

A solution to the problem posed is a device for protecting a predetermined surface capable of preventing it from supporting any external stresses, such as pressure and shear, and capable of being placed on the skin of a patient to prevent and protect bedsores in particular, and as it includes:
- a first rigid part, called a concentrator, capable of supporting said external stresses and whose projection surface on the surface, perpendicular to it, is at least equal to said surface to be protected,
- at least a second part having a deformable part and called a transmitter, supporting and blocking the concentrator at least radially, and said transmitter receiving the forces resulting from the stresses exerted on the concentrator maintains the latter at a minimum height above said surface to protect, when the concentrator transmits said forces to it, and
- at least a third part, called an effector, capable of being placed against a so-called external support surface, surrounding at least the surface to be protected without covering it, the contact surface of said effector against the support surface being of shape adapted to it, and this effector is able to take charge of the forces which the concentrator transmits to it by the transmitter to distribute them in pressure exerted on said external support surface.

According to the above characteristics, the surface protection device is called a pressure transfer system.

According to other characteristics of the invention, the device for protecting a predetermined surface also comprises:
- a main matrix capable of supporting the force generated by the external constraints exerted on the system in particular by the above pressure transfer which can be placed on this matrix, hollowed out to the right of the surface to be protected and capable of being positioned and arranged around it,
- a closure system for the hollowed-out part made from a breathable and waterproof material and constituting with the main matrix a “protective cover” for the area to be protected.

In a particular embodiment, said main matrix also comprises a holding mechanism, arranged around the recessed part of the main matrix, of a thickness at least equal to a predetermined height, called safety distance, and having a resistance to the deformation necessary to ensure said safety distance when external stresses are exerted on the device.

Thus the present invention responds to the problem posed previously and also provides, as the description below specifies, new functionalities such as for the main application of the invention:
- total relief of external stresses such as friction, shear and pressure, without the risk of transferring bedsores to surfaces other than the one to be protected;
- maintenance of the conditions of this discharge whatever the position of the surface to be protected, in particular when the patient changes position, in particular those resulting in a high concentration of pressure on the surface to be protected - risk zone - and this thanks to the portability that the device allows;
- comfort and efficiency increased by the mobility allowed by this portability of the device;
- placing the surface to be protected under a protective cover without pressure, without shearing, without friction, without maceration;
- control of the development of pressure sores without having to remove the device - which thus provides a benefit for the nursing staff - ease of implementation and inspection, significant reduction in the need or frequency of position changes.

It should however be noted that the constituent elements of the invention go beyond the sole field of bedsores and can for example find applications for the care of existing wounds, for the prevention of purulent or non-purulent irritation of the skin, but also in other areas, to provide relief in cases of painful position – for example sitting in a car, motorbike or bicycle, or sitting in everyday life – or even for long-term expeditions such as travel plans on the planet Mars, or even for the protection of any biological or non-biological surface.

Furthermore, the device according to the invention can be integrated into supports intended for the prevention of pressure sores - such as cushions, seats, mattresses, pillows, etc. - or for postural seating comfort.

Brief description of the figures

In the remainder of the description, we refer, in the context of the main application of the invention, to the prevention of bedsores, but as indicated previously this does not reduce the field of application and other modes embodiments are possible within the scope of the present invention.

Thus in the examples of embodiment and application described below, we will designate in particular as patient a person suffering from a risk of occurrence of bedsores, a bedsore or any other form of wounds under medical supervision but The use of the device according to the invention can be broader and for example intended to be worn by motorists, or adapted to a motorcycle saddle, or even used as comfort clothing to relieve certain areas of the body.

Other characteristics and advantages of the invention will appear during reading the detailed description below of several examples of achievements and for the understanding of which we will refer to the appended drawings, in which:

- there is a simplified sectional view of a first embodiment of the invention;

- there is a simplified sectional view of a second embodiment of the invention including that shown on the and a closed hollowed-out main die part;

- there is a simplified sectional view of a third embodiment of the invention including the same matrix part as that shown on the ;

- there is a simplified sectional view of a fourth embodiment of the invention including the same common die part as that shown in Figures 2 and 3;

- there is a general view of a part 14 of the body of a patient for which different devices can be positioned according to the invention, thanks to the same short-type underwear (not shown) adapted to the part 14 of the body considered, on five specific areas that may be subject to pressure sores, such as the sacrum 19, the ischium 17 and the trochanters 18.

Claims (9)

Device for protecting a predetermined surface (9) capable of preventing it from supporting any external stresses, such as pressure and shear, and capable of being placed on the skin (4) of a patient to prevent and protect in particular bedsores, characterized in that it comprises:
- a first rigid part (8), called a concentrator, capable of supporting said external stresses and whose projection surface on the surface (9), perpendicular to it, is at least equal to said surface (9) to be protected,
- at least a second part (10) having a deformable part and called a transmitter, supporting and blocking at least radially the concentrator (8), and said transmitter receiving the forces resulting from the stresses exerted on the concentrator (8) keeps it at a minimum height (h) above said surface to be protected (9), when the concentrator (8) transmits said forces to it, and
- at least a third part (11), called effector, capable of being placed against a so-called external support surface (3), surrounding at least the surface (9) to be protected without covering it, the part of the contact surface of said effector (11) against the support surface (3) being of shape adapted to it, and this effector (11) is able to take charge of the forces that the concentrator (8) transmits to it by the transmitter ( 10) to at least distribute them in pressure exerted on said external support surface (3). Device for protecting a predetermined surface (9) according to claim 1, characterized in that the support surface (3) of the effector (11) is a surface capable of being located beyond and in continuity with that (9) to be protected and the transmitter (10) consists of at least one rigid part of elongated shape, at least part of which extends radially beyond the periphery of the concentrator (8) with a shape of length and inclination, relative to to the concentrator (8) and the effector (11), which ensure the minimum height (h). Device for protecting a predetermined surface (9) according to claim 1, characterized in that the effector (11) has a part (3') of its bearing surface (3) perpendicular to that (9) to be protected and the transmitter (10) consists of at least one element (16) which moves radially under the action of the forces transmitted by the concentrator (8) towards the effector (11), said at least element (16) , having a reversible resistance to compression, bearing on the support surface (3) of the effector (11) which in return exerts a reactive force which balances all the forces and maintains the concentrator (8) at the called minimum height (h). Device for protecting a predetermined surface (9) according to any one of claims 1 and 2 characterized in that the concentrator (8) and the transmitter (10) are integral and fixed to each other. Device for protecting a predetermined surface (9) according to any one of claims 1 to 4, characterized in that it comprises:
- a main matrix (1) capable of supporting the force generated by the external constraints exerted on the device, hollowed out (2) in line with the surface (9) to be protected and capable of being positioned and arranged around it;
- a closure system (6) of the recessed part (2) made of a breathable and waterproof material and constituting with the main matrix (1) a “protective cover” of the area to be protected. Device for protecting a predetermined surface (9) according to claim 5 characterized in that the main matrix (1) comprises a holding mechanism (5), arranged around its recessed part (2), of a thickness at least equal to a predetermined height (d), called safety distance, and having a resistance to deformation necessary to ensure said safety distance (d) when external stresses are exerted on the device. Device for protecting a predetermined surface (9) according to any one of claims 5 and 6 characterized in that the base of the matrix (1) in contact with the external support surface (3) is covered with a material capable of constituting, under this base, a sealing film (7) with the external support surface (3). Device for protecting a predetermined surface (9) according to claim 7 characterized in that, the closures (6 and 7) of the recessed part (2) of the main matrix (1) placing the surface to be protected (9) under controllable atmosphere, it includes measuring instruments capable of controlling the state and evolution factors of this atmosphere. System for positioning and maintaining a device for protecting a predetermined surface (9) according to any one of claims 1 to 8, characterized in that it comprises a matrix made of various materials, which integrates said device and which is adapted on the one hand to the morphology of the zone considered bringing together the surface to be protected (9) and the external support surface (3) and on the other hand to the overall functional destination of said device which positioning system and holding device being capable on the one hand of ensuring the portability of said device and on the other hand of allowing precise positioning and holding it in place.