WO2010011148A1

WO2010011148A1 - Negative pressure wound therapy system

Info

Publication number: WO2010011148A1
Application number: PCT/NZ2009/000147
Authority: WO
Inventors: Frederick George
Original assignee: Frederick George
Priority date: 2008-07-24
Filing date: 2009-07-24
Publication date: 2010-01-28

Abstract

A negative pressure wound therapy system comprising an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and the sleeve having at least one sealable port through which fluid may be evacuated, and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

Description

NEGATIVE PRESSURE WOUND THERAPY SYSTEM

FIELD OF THE INVENTION

The invention generally relates to a negative pressure wound therapy system.

BACKGROUND TO THE INVENTION

Negative pressure applied to a wound on a patient may promote healing of the wound for example by promoting blood flow to the wound. However, existing negative pressure wound therapy systems may be complicated and expensive. It may be a time consuming job for a skilled nurse to properly apply a negative wound therapy system to a patient.

Typically, such systems comprise a dressing and catheter which are applied to the wound. A plastic patch is applied over the dressing and catheter and is sealed against the patient's skin using an adhesive. A partial vacuum is created inside the plastic patch by pumping fluid out. The patch may be prone to leaking, and leaks can be hard to find and time consuming to fix. The system may comprise computerised electrical pumps with electrical cords and tubes which can limit the patient's mobility. The patch must be removed in order to change dressing, and this repeated removing can damage protective epithelial cells in some patients.

It is an object of the invention to provide an improved negative pressure wound therapy system or to at least provide the public with a useful choice.

SUMMARY OF THE INVENTION

In a first aspect the invention broadly consists in a negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and the sleeve having at least one sealable port through which fluid may be evacuated; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

Preferably, the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to die patient's body.

Preferably, the perforated body is a substantially hollow body with one or more openings.

Preferably, the perforated body is an open— celled body.

Preferably, the negative pressure wound therapy system comprises an integral elastic ring around each opening arranged to hermetically seal the opening against the patient's skin.

Preferably, the negative pressure wound therapy system comprises a dressing between the wound and the perforated body.

Preferably, the negative pressure wound therapy system comprises an open channelled material between the skin around the wound and the sleeve.

Preferably, the negative pressure wound therapy system comprises an absorbent material between the perforated body and the sleeve.

Preferably, the sleeve is arranged to fit over a patient's foot. More preferably, the negative pressure wound therapy system comprises a footbed. Even more preferably, the footbed is formed from the perforated body extending along the sole of the foot.

Preferably, the sleeve comprises two openings and is arranged to fit over a patient's arm. Preferably, the sleeve comprises two or more openings and arranged to fit over a patient's torso.

In a second aspect the invention broadly consists in a kit of parts comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and the sleeve having at least one sealable port through which fluid may be evacuated; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

In a third aspect the invention broadly consists in a negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

In a fourth aspect the invention broadly consists in a kit of parts comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

The second, third, and fourth aspects of die invention may have any one or more of the features mentioned in respect of the first aspect of the invention. In a fifth aspect the invention broadly consists in a method of applying negative pressure to a wound comprising the steps of: placing a perforated body over the wound, the perforated body arranged to provide a space to create a partial vacuum over the wound when fluid is evacuated from a sleeve fitted to the patient's body; fitting an air impervious sleeve, having at least one opening that is arranged to be sealed against the patient's skin, over the patient's body part in proximity to the wound so that the perforated body is provided between the wound and the sleeve; _v sealing the opening(s) of the sleeve against the patient's skin; and evacuating fluid from the sleeve so that a partial vacuum is created in the space over the wound provided by the perforated body.

Preferably, the step of evacuating fluid comprises evacuating fluid from a sealable port provided on the sleeve.

Preferably, the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body

Preferably, the method of applying a negative pressure to a wound further comprises the step of dressing the wound.

Preferably, the method of applying a negative pressure to a wound further comprises the step of fitting an open channelled material between the skin around the wound and the sleeve.

Preferably, the method of applying a negative pressure to a wound further comprises the step of providing an absorbent material between the perforated body and the sleeve.

In a sixth aspect the invention broadly consists in use, in the manufacture of a negative pressure wound therapy system or kit for applying negative pressure to a wound, of an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides vacuum space above the wound to create a partial vacuum over the wound when fluid is evacuated from the sleeve.

In a seventh aspect the invention broadly consists in use of a negative pressure wound therapy system or Mt including an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve, for the technical purpose of applying a negative pressure to a wound.

In an eighth aspect the invention broadly consists in negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising an opening arranged to be sealed against the patient's skin, and the sleeve having a check valve through which fluid may be evacuated; a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve; and an integral elastic ring around the opening arranged to hermetically seal the opening against the patient's skin.

The sixth, seventh, and eighth aspects of the invention may have one or more of the features mentioned in respect of the first aspect of the invention.

The phrase "perforated body" as used in this specification and claims, unless the context dictates otherwise, is intended to mean any body that is shaped or formed such that it can act to space at least a portion of the sleeve from the wound site and which also acts to form a vacuum space that may be vacated of fluid to form a partial vacuum between the sleeve and the wound site, and including by way of example only any substantially hollow body or formation, cup-shaped or otherwise, with one or more apertures through the body, or a substantially solid but porous or open-celled body and where the hollow or solid bodies may be either rigid or resiliently deformable depending on the application.

The term "fluid" as used in this specification and claims, unless the context dictates otherwise, is intended to mean any gas or liquid that may be evacuated from the sleeve in order to form a partial vacuum in the sleeve and may include, but is not limited to, air, any gas that may be generated by the human body, water, and any liquid that may be generated by the human body such as exudates from wounds including blood, pus, plasma, and mucus.

The term "comprising" as used in this specification and claims means "consisting at least in part of. When interpreting each statement in this specification and claims that includes the term "comprising", features other than that or those prefaced by the term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner.

As used herein, the term "and/or" means "and" or "or", or both.

As used herein, "(s)" following a noun means the plural form of the noun, or the singular form of the noun, or both.

The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will be described by way of example only and with reference to the drawings, in which:

Figure 1 is a perspective view of one embodiment of a negative pressure wound therapy system of the invention with a sleeve arranged to fit over a patient's foot, and a valve provided on the sleeve; Figure 2 is a perspective view of another embodiment of a negative pressure wound therapy system of the invention with a sleeve arranged to fit over a patient's foot, and a port provided on the sleeve;

Figure 3 is a perspective view of another embodiment of a negative pres.sure wound therapy system of the invention with a sleeve arranged to fit over a patient's foot, and a conduit or tube passing between the patient's skin and an opening of the sleeve;

Figure 4 is a close-up cross-section view of the negative pressure wound therapy system of the invention showing a perforated body covering a wound;

Figure 5 is a perspective view of another embodiment of a negative pressure wound therapy system of the invention in which the perforated body is arranged to extend along a patient's foot, and shown with the sleeve removed;

Figure 6 is a perspective view of another embodiment of a negative pressure wound therapy system of the invention with a sleeve arranged to fit over a patient's arm; and Figure 7 is a perspective view of another embodiment of a negative pressure wound therapy system of the invention with a sleeve arranged to fit over a patient's torso.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The invention relates to a negative pressure wound therapy system comprising a sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, and a valve arranged to allow fluid, including air, to flow out of the sleeve. A perforated body is provided between the wound and the sleeve to create a vacuum space such that a partial vacuum may be created and maintained over or in the vicinity of the wound.

Referring to Figures 1 to 3, one embodiment of the negative pressure wound therapy system 2 comprises a sleeve 4 arranged to fit over part of a patient's body and a wound. The sleeve 4 is preferably flexible such that it can substantially conform to the contours of the body part to which it is fitted but may alternatively be rigid, or may have flexible parts and rigid parts. In the embodiment shown in Figure 1, the sleeve 4 may be arranged to fit over a patient's foot, toes, and ankle for example if a wound is located on the patient's heel, sole of the foot, or top of the foot. However, in other embodiments, the sleeve 4 may be arranged to fit over any suitable part of a patient's body such as an arm, leg, torso, or hand. The sleeve 4 is impervious to fluid such as air and wound exudates and discharge. This means that fluid is not able to flow or pass through the sleeve 4 itself. The sleeve 4 may be made from vinyl, rubber, silicone, plastic, any suitable elastomer, or any other suitable material. The sleeve 4 comprises one or more openings 10 arranged so that the sleeve 4 can be fitted around part of a patient's body. The or each opening 10 is arranged to be sealed against a patient's skin so that a partial vacuum can be created inside the sleeve 4, and so that no fluid is able to enter or exit the sleeve 4 through the opening 10 once the partial vacuum is created.

In the embodiment shown in Figure 1, the sleeve 4 comprises a valve 6 operable to allow fluid to flow from the inside of the sleeve 4 to the outside of the sleeve 4. The valve 6 may . be integral with the sleeve 4, or provided on the sleeve 4 in any other suitable manner. The valve 6 may be a one-way valve or check valve such as a floating disk valve, a duckbill valve, a spring loaded valve, or any other suitable valve. Fluid may be trapped inside the sleeve 4 against the patient's skin when the sleeve is fitted over part of the patient's body. The fluid may be evacuated from the sleeve 4, for example by using a pump or other vacuum apparatus operatively connected to the valve, so that a partial vacuum may be created inside the sleeve 4 in order to apply negative pressure wound therapy to a wound. By way of example, a vacuum apparatus may be connected to the valve 6 by a tube 8 or conduit or in any other suitable manner. The tube 8 may be flexible or rigid. Once the sleeve 4 is evacuated of fluid to the desired degree or level, and the partial vacuum is created, the vacuum apparatus or tube 8 or both may be disconnected from the valve 6, and the valve 6 may prevent fluid from entering the sleeve 4 in order to maintain the partial vacuum within the fitted sleeve.

Referring to Figure 2, in another embodiment, the sleeve 4 may comprise a sealable or operable port 11. The port 11 provides a flow path through the sleeve 4 to enable fluid to be evacuated in order to create a partial vacuum inside the sleeve 4. A vacuum apparatus may be connected to the port 11 for example via a tube or conduit in order to evacuate fluid from the sleeve 4. Once the sleeve 4 is evacuated, and the partial vacuum is created, the vacuum apparatus may be disconnected from the port 11, and the port 11 may be sealed, plugged, or closed to maintain the partial vacuum within the fitted sleeve 4. The port 11 may be sealed, plugged, or closed with a plug or bung adapted to couple with the port 11 so that the sealed port 11 is impervious to fluid flow. Alternatively, a valve may be coupled with the port 11 that is arranged to prevent fluid flow into the sleeve 4 through the port 11. Alternatively, the tube or conduit may comprise a valve along its length and such tube or conduit may be permanently coupled with the port 11 to prevent fluid flow into the sleeve 4. However, the port 11 may be sealed, plugged, or closed in any suitable manner. In one form, the port 11 may be in the form of an oral inflation/ deflation valve.

Referring to Figure 3, in another embodiment, a conduit or tube 8 may run from the inside of the sleeve 4 to the outside of the sleeve 4 by passing between the patient's skin and the opening 10. The conduit or tube 8 provides a flow path to enable fluid to be evacuated in order to create a partial vacuum inside the sleeve 4. A vacuum apparatus may be connected to the conduit or tube 8 in order to evacuate fluid from the sleeve 4. In one form, once the sleeve 4 has been evacuated, the vacuum apparatus may be disconnected from the conduit or tube 8, and the conduit or tube 8 may be sealed, plugged, or closed to maintain the partial vacuum within the fitted sleeve 4. The conduit or tube 8 may be sealed, plugged, or closed with a plug, bung, valve, or in any other suitable manner. In this form, the conduit or tube 8 may remain in place permanently while the negative pressure wound therapy system is fitted to the patient. The conduit or tube 8 may be used to maintain the vacuum as required, or may act as a catheter. In another form, the conduit or tube 8 may be may be removed from the sleeve 4 after the fluid has been evacuated. The conduit or tube 8 may be a separate component that is inserted into the sleeve 4 once fitted, or alternatively the conduit may be fixed or attached to the sleeve such that one end of the conduit or tube 8 is located inside the sleeve 4, and the other end is located outside the sleeve 4. In a further alternative, the conduit or tube 8 need not necessarily extend out opening 10 as shown, but may be connected or operatively coupled at one end to a port or aperture provided through the surface of the sleeve 4, for example like the port 11 shown in Figure 2.

In the embodiments of Figures 1 to 3, the sleeve 4 may resemble a sock with one opening 10 arranged so that a patient can insert their foot into the sleeve 4. However, in other embodiments the sleeve 4 may comprise two or more openings so that the sleeve 4 can be fitted to other body parts or about other body regions. Each opening 10 is arranged to be hermetically sealed against a patient's skin so that fluid, including air, may not enter or exit the sleeve 4 through the opening 10. In embodiments where a tube 8 or conduit is passed under the opening 10, the sleeve 4 should also be hermetically sealed against outside of the tube 8, and the outside of the tube 8 should be hermetically sealed against the patient's skin so that no fluid may enter or exit the sleeve 4 through the opening 10 or where the tube 8 passes under the opening 10. In such embodiments, if the tube 8 or conduit is removed after evacuation of fluid, the opening 10 may need to be sealed against the patient's skin at the point where the tube 8 or conduit was provided. Preferably, the sleeve 4 comprises an integral resiJient, elastic cuff or ring that encircles the opening 10 and that is arranged to stretch over and seal against the patient's skin. A resilient, elastic cuff or ring may quickly and reliably seal the opening 10 of the sleeve 4. If a conduit or tube 8 is removed from between a patient's skin and a cuff or ring, the cuff or ring may quickly and automatically seal against the patient's skin at the point where the tube is removed. Alternatively, the opening 10 may be sealed against the patient's skin by using an adhesive, or in any other suitable manner.

Referring to Figure 4, the negative pressure wound therapy system 2 comprises a perforated body 12 provided between a wound 14 on the patient's skin 16 and the sleeve 4. The perforated body 12 is arranged to provide a vacuum space over the wound that may be vacated of fluid in order to create a partial vacuum over the wound 14. In one form, the perforated body 12 may be arranged to withstand the pressure created by the partial vacuum without collapsing. The perforated body 12 contains at least one fluid outlet so that fluid such as air and wound exudates or discharge may flow out of the perforated body 12. The perforated body 12 may be a cup shaped object or shell provided with one or more openings. Alternatively, the perforated body 12 may be made from an open cell foam material or a porous material. The perforated body 12 may be made from plastic, metal, or any other suitable material. The perforated body 12 may be a substantially hollow body or formation with one or more apertures through the body. Alternatively, the perforated body 12 may be a substantially solid but porous or open-celled body. The perforated body 12 may be either rigid or resiliently deformable.

Fluid may be pumped out of the perforated body 12 and sleeve 4 via a valve, port, tube, or conduit, or in any other suitable manner with a vacuum apparatus, such as a pump, (not shown) or in any other suitable manner. A partial vacuum may be created over or in close vicinity of the wound 14 when the space underneath or within tine perforated body 12 is evacuated of fluid. Evacuation of the fluid within the sleeve 4 may cause the sleeve 4 to collapse against the perforated body 12 and the skin 16

by the sleeve (except for the area of skin covered by the perforated body 12). A desired level or degree of vacuum may be achieved by using a feedback mechanism on an electric pump, or by using a specially designed manual pump, such as a squeeze bulb pump, that will only allow for a certain maximum vacuum pressure to be created. In forms where a squeeze pump is provided, the squeeze pump may be integral with the sleeve 4, or may be external to the sleeve 4. The patient or another person (such as a nurse) may visually or tactually determine if the vacuum pressure decreases (which may indicate a leak in the sleeve 4 or opening 10) as the sleeve 4 may loosen on the body part or collapse more loosely against the patient's skin 16. Fluid may be evacuated from the sleeve 4 in any suitable manner.

When applying the negative pressure wound therapy system to a patient to treat a wound 14, the perforated body 12 may be placed over the wound 14 in order to fully or partially cover it. The sleeve 4 may then be slid over the patient's body part in proximity to the wound 14. Alternatively, the sleeve 4 may be slid over the patient's body part first, and then the perforated body 12 may be slid between the sleeve 4 and the patient's skin until it is positioned between the wound 14 and the sleeve 4. Alternatively, the perforated body 12 may be positioned in the sleeve 4 before applying it to the patient. In this form, the sleeve 4 and perforated body 12 may both then be slid over the body part together, in order to position the perforated body 12 over the wound 14.

A dressing 18 may be applied directly to the wound 14 so that it forms a barrier between the wound 14 and the perforated body 12. The dressing 18 may be paraffin impregnated, antibiotic, silver ion, colloidal, formed plastic, or any other suitable type of dressing. The dressing 18 may help protect the wound 14 from hard edges or sides that may be provided on the perforated body 12.

An open channelled material 20 may be placed on the skin 16 around the wound 14. The open channelled material 20 may reduce friction between the skin 16 and the sleeve 4 so that it is easier to slide the sleeve 4 on and off the body part. The open channelled material 20 may also provide a pathway so air between the skin 16 and the sleeve 4 may be more easily evacuated. The open channelled material 20 may be a cotton weave, or any other suitable material. The open channelled material 20 may entirely cover the body part within the sleeve 4, or may only surround the skin 16 in proximity to the wound 14. The open channelled material 20 should not extend under or past the seal of the opening 10 as this may provide a pathway for fluid to enter the sleeve 4 and may affect the integrity of the partial vacuum. The open channelled material 20 may be made from natural-fibre or synthetic materials such as cotton, wool, natural or synthetic flocking, polypropylene, or any other suitable material. The open channelled material 20 may be adhered to the inside of the sleeve 4. In embodiments where the negative pressure wound therapy system is applied to the foot, the open channelled material 20 may be provided by a natural-fibre or synthetic sock. In embodiments where the negative pressure wound therapy system is applied to the hand, the open channelled material 20 may be provided by a natural-fibre or synthetic glove or mitten.

An absorbent material 22 may be provided between the perforated body 12 and the sleeve 4. The absorbent material 22 may be made from cotton, wool, tissue, wood pulp or wood fluff pulp, super absorbent polymer or sodium polyacrylate, or any other suitable material. The absorbent material 22 may absorb any wound exudates that may flow from the wound through the dressing 18 (if provided) and perforated body 12 when the fluid is being or has been evacuated. The dressing 18 may also absorb wound exudates. Alternatively, tubing or a catheter may be provided adjacent to the wound to carry wound exudates out of the sleeve 4 via the valve 6, port 11 , tube 8, or conduit and into a suitable receptacle.

Referring to Figure 5, in embodiments of the negative pressure wound therapy system that comprise a sleeve adapted to fit around a patient's foot, the perforated body 12 may be extended along the sole of the foot 24 to provide a footbed 26. The dressing 18 and absorbent material 22 may also extend along the sole of the foot. The footbed 26 may be a complete or partial footbed, and may comprise other materials, such as an orthotic device. The perforated body 12 may extend to other areas of the foot where wounds are present, such as the top of the foot (not shown) or the heel. Alternatively, a separate perforated body 12 may be provided between a wound 14 and the sleeve if more than one wound to be treated by negative pressure wound therapy is present. In other words, multiple separate perforated bodies could be provided, and one perforated body could be provided on each wound if necessary. Generally, the perforated body 12 will be made from a compressible material when a footbed 26 is provided in this manner. When a compressible perforated body 12 is used, and during weight bearing periods of gait, the compressible perforated body 12 may compress so that wound exudates may be squeezed from the perforated body 12 into absorbent material or into a tube so that it can be expelled via a tube and valve or in any other suitable manner. During non-weight bearing periods of gait, the structural memory of the compressible perforated body 12 may cause it to regain its uncompressed state, and in doing so, maintaining and effecting the partial vacuum over the wound 14. Pressure relieving beds may be provided in other embodiments of the negative pressure wound therapy system for example to prevent a patient forming decubitus ulcers or bedsores.

Referring to Figure 6, in another embodiment, the negative pressure wound therapy system 2 may be arranged to fit over a patient's arm 28 in order to treat a wound located on the arm 28. The sleeve 4 may be worn on the upper arm 30, the lower arm 32, or over the elbow 34, or may extend any suitable length along the arm. Two openings 10 are provided on the sleeve 4 (one opening 10 at each end of the sleeve 4) so that the sleeve 4 can be slipped or slid onto a patient's arm. Each opening 10 is arranged to be sealed against the patient's skin for example by using an integral resilient, elastic cuff or ring that encircles the opening 10, or by using adhesive, or in any other suitable manner as previously described. The sleeve 4 may comprise a valve 6 so that fluid can be evacuated and a partial vacuum can be created over a wound. Alternatively, the sleeve 4 may comprise a port (not shown) so that fluid can be evacuated and a partial vacuum can be created over a wound. Alternatively, the sleeve may comprise a tube or conduit (not shown) passing under one of the openings 10 so that fluid can be evacuated and a partial vacuum can be created over a wound. Fluid may be evacuated from the sleeve 4 in any suitable manner. It will be appreciated that any of the port, valve, and/or conduit evacuating configurations described with respect to this double-opening form of the sleeve.

Referring to Figure 7, in another embodiment, the negative pressure wound therapy system 2 may be arranged to fit over a patient's torso 36 in order to treat a wound located on the torso 36. The sleeve 4 may be worn over the hips, pelvis, upper legs, and lower torso, and may extend any suitable distance along the legs and torso. Three openings 10 may be provided on the sleeve 4 (one opening 10 for each leg and one opening 10 for the torso) so that the sleeve 4 can be slipped or slid onto a patient's torso. Each opening 10 is arranged to be sealed against the patient's skin for example by using an integral resilient, elastic cuff or ring that encircles the opening 10, or by using adhesive, or in any other suitable manner. Alternatively, the sleeve 4 may only comprise two openings 10 and may only extend along the torso for example from the waist to the chest. Again, any of the port, valve, and/or conduit evacuating configurations previously described may be employed with this form of the sleeve. The sleeve 4 may comprise a valve 6 so that fluid can be evacuated and a partial vacuum can be created over a wound. Alternatively, the sleeve 4 may comprise a port (not shown) so that fluid can be evacuated and a partial vacuum can be created over a wound. Alternatively, the sleeve may comprise a tube or conduit (not shown) passing under one of the openings 10 so that fluid can be evacuated and a partial vacuum can be created over a wound. Fluid may be evacuated from the sleeve 4 in any suitable manner. A pressure relieving bed may be provided between the sleeve 4 and the patient's skin to prevent the formation of bedsores. The pressure relieving bed may be formed from any suitable material and may include the perforated body, dressing, or absorbent material. The pressure relieving bed may be provided in any suitable position such as over or in proximity to the sacral region. A pressure relieving bed may be provided in any suitable embodiment of the invention.

In other embodiments, the negative pressure wound therapy system 2 may be arranged to fit over any part of a patient's body in order to treat a wound. For example, a mitten shaped sleeve 4 with one opening 10 may be provided to treat a wound on a patient's hand.

Alternatively, a sleeve 4 similar to the one shown in Figure 6 with two openings 10 may be provided to treat a wound on a patient's leg. Any of the port, valve, and/or conduit evacuating configurations previously described may be employed with any suitable embodiment of the sleeve.

The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention as defined by the accompanying claims.

Claims

1. A negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and the sleeve having at least one sealable port through which fluid may be evacuated; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

2. A negative pressure wound therapy system according to claim 1 where the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body.

3. A negative pressure wound therapy system according to either of claims 1 or 2 where the perforated body is a substantially hollow body with one or more openings.

4. A negative pressure wound therapy system according to either of claims 1 or 2 where the perforated body is an open-celled body.

5. A negative pressure wound therapy system according to any one of claims 1 to 4 comprising an integral elastic ring around each opening arranged to hermetically seal the opening against the patient's skin.

6. A negative pressure wound therapy system according to any one of claims 1 to 5 comprising a dressing between the wound and the perforated body.

7. A negative pressure wound therapy system according to any one of claims 1 to 6 comprising an open channelled material between the skin around the wound and the sleeve.

8. A negative pressure wound therapy system according to any one of claims 1 to 7 comprising an absorbent material between the perforated body and the sleeve.

9. A negative pressure wound therapy system according to any one of claims 1 to 8 where the sleeve is arranged to fit over a patient's foot.

10. A negative pressure wound therapy system according to claim 9 comprising a footbed.

11. A negative pressure wound therapy system according to claim 10 where the footbed is formed from the perforated body extending along the sole of the foot.

12. A negative pressure wound therapy system according to any one of claims 1 to 8 where the sleeve comprises two openings and is arranged to fit over a patient's arm.

13. A negative pressure wound therapy system according to any one of claims 1 to 8 where the sleeve comprises two or more openings and arranged to fit over a patient's torso.

14. A kit of parts comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and the sleeve having at least one sealable port through which fluid may be evacuated; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

15. A kit of parts according to claim 14 where the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body.

16. A kit of parts according to either of claims 14 or 15 where the perforated body is a substantially hollow body with one or more openings.

17. A kit of parts according to either of claims 14 or 15 where the perforated body is an open— celled body.

18. A kit of parts according to any one of claims 14 to 17 comprising an integral elastic ring around each opening arranged to hermetically seal the opening against the patient's skin.

19. A kit of parts according to any one of claims 14 to 18 comprising a dressing between the wound and the perforated body.

20. A kit of parts according to any one of claims 14 to 19 comprising an open channelled material between the skin around the wound and the sleeve.

21. A kit of parts according to any one of claims 14 to 20 comprising an absorbent material between the perforated body and the sleeve.

22. A negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

23. A negative pressure wound therapy system according to claim 22 comprising a tube arranged to extend into the sleeve between the patient's skin and an opening in the sleeve, such that fluid may be evacuated from the sleeve through the tube.

24. A negative pressure wound therapy system according to either of claims 22 or 23 where the perforated body is a substantially hollow body with one or more openings.

25. A negative pressure wound therapy system according to either of claims 22 or 23 where the perforated body is an open— celled body.

26. A negative pressure wound therapy system according to any one of claims 22 to 25 comprising an integral elastic ring around each opening arranged to hermetically seal the opening against the patient's skin.

27. A negative pressure wound therapy system according to any one of claims 22 to 26 comprising a dressing between the wound and the perforated body.

28. A negative pressure wound therapy system according to any one of claims 22 to 27 comprising an open channelled material between the skin around the wound and the sleeve.

29. A negative pressure wound therapy system according to any one of claims 22 to 28 comprising an absorbent material between the perforated body and the sleeve.

30. A kit of parts comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin; and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve.

31. A kit of parts according to claim 30 comprising a tube arranged to extend into the sleeve between the patient's skin and an opening in the sleeve, such that fluid may be evacuated from the sleeve through the tube.

32. A kit of parts according to either of claims 30 ox 31 where the perforated body is a substantially hollow body with one or more openings.

33. A kit of parts according to either of claims 30 or 31 where the perforated body is an open— celled body.

34. A kit of parts according to any one of claims 30 to 33 comprising an integral elastic ring around each opening arranged to hermetically seal the opening against the patient's skin.

35. A kit of parts according to any one of claims 30 to 34 comprising a dressing between the wound and the perforated body.

36. A ldt of parts according to any one of claims 30 to 35 comprising an open channelled material between the skin around the wound and the sleeve.

37. A kit of parts according to any one of claims 30 to 36 comprising an absorbent material between the perforated body and the sleeve.

38. A method of applying negative pressure to a wound comprising the steps of: placing a perforated body over the wound, the perforated body arranged to provide a space to create a partial vacuum over the wound when fluid is evacuated from a sleeve fitted to the patient's body; fitting an air impervious sleeve, having at least one opening that is arranged to be sealed against the patient's skin, over the patient's body part in proximity to the wound so that the perforated body is provided between the wound and the sleeve; sealing the opening(s) of the sleeve against the patient's skin; and evacuating fluid from the sleeve so that a partial vacuum is created in the space over the wound provided by the perforated body.

39. A method of applying negative pressure to a wound according to claim 38 where the step of evacuating fluid comprises evacuating fluid from a sealable port provided on the sleeve.

40. A method of applying negative pressure to a wound according to claim 39 where the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body

41. A method of applying a negative pressure to a wound according to any one of claims 38 to 40 further comprising the step of dressing the wound.

42. A method of applying a negative pressure to a wound according to any one of claims 38 to 41 further comprising the step of fitting an open channelled material between the skin around the wound and the sleeve.

43. A method of applying a negative pressure to a wound according to any one of claims 38 to 42 further comprising the step of providing an absorbent material between the perforated body and the sleeve.

44. Use, in the manufacture of a negative pressure wound therapy system or kit for applying negative pressure to a wound, of an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides vacuum space above the wound to create a partial vacuum over the wound when fluid is evacuated from the sleeve.

45. Use, in the manufacture of a negative pressure wound therapy system or kit for applying a negative pressure to a wound, according to claim 44 where the sleeve comprises at least one sealable port through which fluid may be evacuated.

46. Use, in the manufacture of a negative pressure wound therapy system or kit for applying a negative pressure to a wound, according to claim 45 where the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body.

47. Use, in the manufacture of a negative pressure wound therapy system or kit for applying a negative pressure to a wound, according to claim 44 comprising a tube arranged to extend into the sleeve between the patient's skin and an opening in the sleeve, such that fluid may be evacuated from the sleeve through the tube.

48. Use of a negative pressure wound therapy system or kit including an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising at least one opening arranged to be sealed against the patient's skin, and a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve, for the technical purpose of applying a negative pressure to a wound.

49. Use of a negative pressure wound therapy system or kit according to claim 48 where the sleeve comprises at least one sealable port through which fluid may be evacuated.

50. Use of a negative pressure wound therapy system or kit according to claim 49 where the sealable port comprises a valve that is operable to allow fluid within the sleeve to be evacuated when the sleeve is fitted and the opening(s) are sealed to the patient's body.

51. Use of a negative pressure wound therapy system or kit according to claim 48 comprising a tube arranged to extend into the sleeve between the patient's skin and an opening in the sleeve, such that fluid may be evacuated from the sleeve through the tube.

52. A negative pressure wound therapy system comprising: an air impervious sleeve arranged to fit over a wound and part of a patient's body in proximity to the wound, the sleeve comprising an opening arranged to be sealed against the patient's skin, and the sleeve having a check valve through which fluid may be evacuated; a perforated body arranged to be positioned between the wound and the sleeve such that the perforated body provides a vacuum space above the wound to enable at least a partial vacuum over the wound to be created when fluid is evacuated from the sleeve; and an integral elastic ring around the opening arranged to hermetically seal the opening against the patient's skin.