AU2021218054A1

AU2021218054A1 - Apparatus for supplying fluid to a tissue area

Info

Publication number: AU2021218054A1
Application number: AU2021218054A
Authority: AU
Inventors: Thomas Heinrich Barnes; Dexter Chi Lun Cheung; Howard Kuo-Hao CHIU; Margaret Shi LU
Original assignee: Fisher and Paykel Healthcare Ltd
Current assignee: Fisher and Paykel Healthcare Ltd
Priority date: 2021-08-17
Filing date: 2021-08-17
Publication date: 2023-03-09

Abstract

An apparatus is provided for supplying fluid to tissue of a patient. The apparatus includes an inflatable receptacle positionable at a tissue area. The receptacle comprises one or more walls and is adapted to receive a fluid. The one or more walls comprise at least one section adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area. The apparatus further includes a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the tissue area. 1/17 4 45 40 10 54 15 10 50 38 34 32 20 F-gure2 24 60 22 12 35 20 Figure 1 E 11.45 4 0 54 15 5 38 10 34 3 32 35 24 20 22 Figure 2

Description

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"Apparatus for supplying fluid to a tissue area"

Technical Field

[0001] The present invention relates to an apparatus for supplying fluid to a tissue area.

Background

[0002] The application of topical oxygen to a tissue area can improve tissue health. For example, in cases where the tissue area comprises a wound, the application of topical oxygen can aid healing. This is because healing can involve increased cell metabolic activity (which demands a large amount of oxygen). The application of topical oxygen to the wound can help to meet this demand. Exposing the wound surface to a negative-pressure environment can also aid healing. The negative-pressure environment helps to contract the wound and remove exudate from the wound.

[0003] Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present disclosure as it existed before the priority date of each of the appended claims.

Summary

[0004] The present disclosure describes embodiments of an apparatus for supplying fluid to a tissue area. At least one receptacle, which includes at least a section made from a material adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area, may be positioned against the tissue area. The tissue area may include, for example, a wound. The material may be, for example, a membrane. The material allow fluid molecules, for example oxygen gas molecules, inside of the receptacle, to diffuse from the inside of the receptacle to the wound. At the same time, the material substantially provides a barrier to liquid. An outer surface of the material through which molecules diffuse may contact the tissue to be treated and/or adjacent tissue, for example a wound and/or the healthy tissue that surrounds the wound. Because the membrane of the receptacle is in contact with the wound surface during use, the delivery of fluid to the wound is not significantly affected by the amount of exudate withdrawn from the wound. Some embodiments of the apparatus include an absorbent layer positioned away from the wound. Positioning the absorbent layer away from the wound reduces the possibility of tissue cells growing into the absorbent layer and pieces of absorbent layer being left in the wound when the device is removed.

[0005] According to an aspect, an apparatus for supplying fluid to a tissue area comprises an inflatable receptacle positionable at a tissue area, the receptacle comprising one or more walls and being adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area; and a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle, and the tissue area. The arrangement of the apparatus may facilitate the simultaneous application of therapeutic fluid molecules to the tissue area and the application of negative pressure treatment without significantly impacting the application of the therapeutic fluid molecules to the tissue area. The tissue area may comprise a wound area.

[0006] In some embodiments, the receptacle is moveable within the compartment substantially bounded by the cover, the receptacle and the tissue area.

[0007] In some embodiments, the receptacle may be in the form of a bag. The receptacle is inflatable, and depends on the presence of fluid to maintain its size and shape. However, the receptacle need not be fully inflated and the apparatus is operable with a partially inflated receptacle. The receptacle may be configured to contact the tissue area. At least the at least one section of the receptacle may be conformable with a surface of the tissue area. The at least one section of the receptacle may comprise a stretchable material. The at least one section of the one or more walls of the receptacle may have an undulating outer surface when at least partially inflated. The inflatable receptacle may provide a substantially even concentration of fluid within the receptacle and a substantially even diffusion of molecules through the section through which molecules diffuse to the tissue. It may also provide a substantially even pressure distribution of molecules over the tissue. The receptacle may act as a reservoir and contain volumes of fluid. The fluid in the receptacle may be used in the event of a disruption to the supply of fluid to the receptacle e.g. if the fluid source becomes disconnected from the receptacle.

[0008] In some embodiments, the one or more walls of the receptacle other than the at least one section allow molecules within the fluid to diffuse from the receptacle to the tissue area.

[0009] The receptacle may be connected to the cover at a single connection point or at two connection points. This minimal connection between the receptacle and the cover enables the receptacle to be movable within the compartment bounded by the cover, the receptacle, and the tissue area, which may help it to conform to tissue with complex geometries and/or varying topologies.

[0010] The apparatus may further comprise a fluid inlet conduit arranged in fluid communication with the receptacle for delivery of fluid to the receptacle. In some embodiments, the cover may have a first opening through which the fluid inlet conduit passes or to which the fluid inlet conduit is connected. The receptacle may be connected to the cover via the fluid inlet conduit. The fluid inlet conduit may include a pressure relief valve. In some embodiments, the compartment substantially bounded by the cover, the receptacle, and the tissue area may also be bounded by additional components of the apparatus that may be present and still be substantially bounded by the cover, the receptacle and the tissue area. For example, in some embodiments, the compartment may be further bounded by one or more fluid inlet conduits and/or fluid outlet conduits. In these embodiments, the compartment substantially bounded by the cover, the receptacle and the tissue area may be further bounded by the fluid inlet conduit, including the pressure relief valve if present inside the cover.

[0011] In some embodiments, the apparatus may further comprise at least one fastener for securing the receptacle in place at the tissue area. The fastener may comprise adhesive, such as adhesive tape. It may also comprise a compression dressing that presses and secures the receptacle in place.

[0012] In some embodiments, the cover comprises one or more walls and the one or more walls of the cover are independent of the one or more walls of the receptacle. This arrangement may enable the receptacle to be movable within the compartment, which may help it to conform to tissue having complex geometries and/or varying topologies.

[0013] Alternatively, the receptacle and the cover may share a common wall.

[0014] The receptacle may be fillable with the fluid during use of the apparatus. The receptacle may be filled with the fluid prior to positioning the receptacle at the tissue area. Alternatively, the receptacle may be pre-filled with the fluid during manufacture.

[0015] The one or more walls of the receptacle may define one or more through-holes through the receptacle. Where the tissue includes a wound, these 'through-holes' allow exudate from the wound to be drawn through the holes, in particular when the compartment is under negative pressure. This may result in more exudate being drawn away from the wound.

[0016] In some embodiments, the apparatus may include a plurality of the receptacles. Multiple receptacles can provide additional conformability to the surface of the tissue area for complex geometries and/or varying tissue topologies.

[0017] The apparatus may further comprise structures associated with the at least one section of the receptacle, the structures being configured to contact the tissue area. The contact may encourage cell growth. The structures may be microstructures. The microstructures may exert forces on the tissue. These forces may result in micro-stresses that stretch the underlying cells and cause them to take on the same signalling pathways as those affected by growth factors. This can encourage cell growth. The microstructures may comprise formations which protrude from the one or more walls of the receptacle. In some embodiments, molecules diffuse through the at least one section of the receptacle and the microstructures into the tissue area.

[0018] The microstructures may consist of formations that protrude from a tissue facing surface of the one or more walls of the receptacle. Each formation may have one or more of a parabolic, trapezoidal, semi-spherical, spherical, pyramidal, conical, or frustoconical shape. Each formation may be a different shape to the other formations. Each formation may be the same shape as one or more of the other formations. The microstructures may have rounded edges and/or corners. Accordingly, in this embodiment there are no sharp edges on the microstructures which could potentially damage cells.

[0019] In some embodiments, the at least one section of the receptacle may comprise a membrane adapted to allow molecules within the fluid to diffuse through it. More specifically, the receptacle may comprise a membrane adapted to allow molecules within the fluid in the receptacle to diffuse through to reach the tissue area. The membrane may be a film, sheet, flexible wall, or the like. The membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area may be substantially pore-free. In some embodiments, the membrane comprises substantially no discontinuities or pores that are visible with an optical or electron microscope at a specified magnification. The specified resolution may be on the order of 1 micrometre. This produces a substantially smooth outer surface to the membrane that helps to prevent exudate from entering the receptacle. It may also discourage the growth of skin cells into pores of the membrane. Molecules within a liquid may only pass from one side of the membrane to the other via diffusion, which further helps to prevent exudate from entering the receptacle. The membrane may also be hydrophobic.

[0020] In some embodiments, the membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area may comprise at least one of the following: liquid silicone rubber, pre-formed silicone sheet, silicone hydrogel, linear low-density polyethylene treated with calcium carbonate, silicone coatings, and high consistency rubber silicone.

[0021] The membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area may be configured to contact the tissue area. The at least one section may be conformable to the surface of the tissue. It may have a wall thickness of between about 20 micrometres and 150 micrometres, for example between approximately 30 micrometres and 130 micrometres, or between approximately 35 micrometres and 100 micrometres, or between approximately 40 micrometres and 80 micrometres or between approximately 45 micrometres and 55 micrometres. In some embodiments, the wall thickness is approximately 50 micrometres.

[0022] In some embodiments, the one or more walls of the receptacle, including the at least one section, comprise the membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area. In other embodiments, the one or more walls of the receptacle, other than the at least one section, comprise a material that is adapted to allow molecules to pass through via molecular diffusion at only a negligible rate of diffusion.

[0023] The cover may be configured to secure the receptacle to the tissue surface. The cover may be configured to press the receptacle onto or into the tissue surface. In some embodiments, the cover may be a separate component that is positionable over the receptacle once the receptacle has been placed on the tissue. Alternatively, the cover may be combined with the receptacle to form a single dressing.

[0024] The cover may comprise a dressing, for example a bandage. The bandage may be wrapped around a body part, for example a limb, of the patient to form the cover. The cover may comprise an adhesive dressing or polyurethane film. Alternatively, the bandage may be a compression bandage.

[0025] In some embodiments, the cover may comprise an absorbent material for absorbing exudate from the tissue area. The absorbent material may be wrapped around a limb of a patient and the bandage may be wrapped around the absorbent material to form the cover.

[0026] The fluid may be deliverable to the receptacle via the first opening in the cover. The first opening may be adapted for receiving the fluid inlet conduit there through. The cover may have a second opening via which the fluid is receivable from the receptacle. The apparatus may further comprise a first fluid outlet conduit arranged in fluid communication with the receptacle, wherein the second opening is adapted for receiving the first fluid outlet conduit. The cover may have a third opening via which the fluid is receivable from the compartment bounded by the cover, the receptacle, and the tissue area. The apparatus may comprise a second fluid outlet conduit arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle, and the tissue area, wherein the third opening is adapted for receiving the second fluid outlet conduit. In these embodiments, the compartment substantially bounded by the cover, the receptacle and the tissue area may be further bounded by one or more of the fluid inlet conduit and the first fluid outlet conduit.

[0027] The apparatus may include a pressure relief valve in communication with the first opening and/or the receptacle, operable to relieve pressure within the first opening and/or receptacle

[0028] In some embodiments, at least one of the fluid inlet conduit, the first fluid outlet conduit and the second fluid outlet conduit may pass into the compartment adjacent an outer edge of the cover.

[0029] At least two of the fluid inlet conduit, the first fluid outlet conduit, and the second fluid outlet conduit may be formed as a single coaxial conduit.

[0030] The cover may be salable to the tissue area, for example to healthy skin adjacent to a wound. In some embodiments, the cover may be hermetically salable to the tissue area. The seal may comprise one of an adhesive seal or a suction seal.

[0031] The cover may comprise one or more walls of a material that is impermeable to bulk transport of gas and/or liquid. For example, a compression bandage dressing may be impermeable to bulk transport of gas and liquid or multiple layers of the compression dressing can substantially reduce permeability to bulk transport of gas relative to a single layer of the compression bandage dressing.

[0032] The apparatus may comprise a negative pressure source arranged in fluid communication with the compartment for applying a negative pressure to the compartment. In some embodiments, the negative pressure source is a pump. In some embodiments, the compartment substantially bounded by the cover, the receptacle, and the tissue area is pressurised during use to form a negative pressure compartment. The compartment may be altered to be between approximately 50 mmHg to 150 mmHg below atmospheric pressure. For example, the pressure may be altered to between approximately 80 mmHg to 125 mmHg, or to between approximately 90 mmHg to 110 mmHg.

[0033] In some embodiments, the fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.. When the tissue comprises a wound, the application of oxygen may aid healing, while the application of carbon dioxide may induce hypoxia and help to trigger angiogenesis.

[0034] The apparatus may further comprise a fluid source. For example, the fluid may be a gas and the gas source may comprise a wall source, gas bottle, gas concentrator, or other gas generator.

[0035] The receptacle may form a reservoir adapted for storing fluid therein. The reservoir may be fillable with the fluid, for example by a clinician prior to positioning the receptacle 10 on the tissue area of the patient or during use of the apparatus. Alternatively, the reservoir may be pre-filled with fluid during manufacture of the apparatus 100. A pressure within the reservoir may be maintainable at a positive pressure. At the same time, the compartment substantially bounded by the cover, the receptacle and the tissue area may be maintainable at a pressure that is below ambient pressure.

[0036] According to another aspect, an apparatus for supplying fluid to a tissue area comprises a receptacle positionable at a tissue area, the receptacle comprising one or more walls adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow fluid to pass from the receptacle to the tissue area; and a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle, and the tissue area; a first opening in the cover via which fluid is deliverable to the receptacle; a second opening in the cover via which fluid is receivable from the receptacle; and a third opening in the cover via which fluid is receivable from the compartment bounded by the cover, the receptacle, and the tissue area. The tissue area may comprise a wound area.

[0037] The apparatus may comprise a tubular fluid compartment having a fluid inlet and a fluid outlet.

[0038] In some embodiments, the at least one section is adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area or the fluid may pass from the receptacle to the tissue area by pore flow.

[0039] The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0040] According to a further aspect, an apparatus for supplying fluid to a tissue area comprises a receptacle positionable at a tissue area, the receptacle comprising one or more walls adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area; and a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle, and the tissue area, wherein the receptacle is moveable within the compartment substantially bounded by the cover, the receptacle and the tissue area. The receptacle may be inflatable. The tissue area may comprise a wound area.

[0041] According to a further aspect, an apparatus for supplying fluid to a tissue area comprises a plurality of receptacles positionable at a tissue area, each receptacle comprising one or more walls adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow fluid to pass from the receptacle to the tissue area. The tissue area may comprise a wound area.

[0042] In some embodiments, the one or more walls of any one of the plurality of receptacles are independent of the one or more walls of the other receptacles of the plurality of receptacles. Each receptacle of the plurality of receptacles may be individually positionable at the tissue area. Each receptacle of the plurality of receptacles may be associated with a separate fluid supply. The apparatus may comprise at least one manifold for providing fluid to each receptacle of the plurality of receptacles.

[0043] The apparatus may comprise a plurality of fluid inlet conduits, wherein each receptacle of the plurality of receptacles is in fluid communication with a respective fluid inlet conduit of the plurality of fluid inlet conduits, via which fluid is supplied to the respective receptacle. Each of the receptacles may be arranged in fluid communication with at least one other of the receptacles. One or more of the receptacles of the plurality of receptacles may have a plurality of microstructures formed thereon. The apparatus may further comprise a cover positionable over the plurality of receptacles to form a compartment substantially bounded by the cover, the plurality of receptacles, and the tissue area. The compartment substantially bounded by the cover, the receptacle and the tissue area may be further bounded by the plurality of fluid inlet conduits.

[0044] In some embodiments, the plurality of fluid inlet conduits are in fluid communication with the manifold and wherein the manifold has a fluid supply conduit that passes through a single opening in the cover. Alternatively, each fluid inlet conduit of the plurality of fluid inlet conduits passes through a respective opening in the cover. In still further embodiments, each fluid inlet conduit of the plurality of fluid inlet conduits extends past an outer edge of the cover to an associated fluid supply. The compartment substantially bounded by the cover, the receptacle and the tissue area may be further bounded by the plurality of fluid inlet conduits, the manifold and the fluid supply conduit.

[0045] In some embodiments, the at least one section allows molecules within the fluid to diffuse from the receptacle to the tissue area. In some embodiments, the at least one section allows the fluid pass from the receptacle to the tissue area by pore flow.

[0046] The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0047] According to a further aspect, an apparatus for supplying fluid to a tissue area comprises a receptacle positionable at a tissue area, the receptacle comprising one or more walls adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow the fluid to pass from the receptacle to the tissue area; a fluid inlet in fluid communication with the receptacle; and a pressure relief valve in communication with the fluid inlet and/or the receptacle and operable to relieve pressure within the fluid inlet and/or receptacle.

[0048] The receptacle may be inflatable. The tissue area may comprise a wound area.

[0049] In some embodiments, the at least one section allows molecules within the fluid to diffuse from the receptacle to the tissue area. In some embodiments, the at least one section allows the fluid pass from the receptacle to the tissue area by pore flow.

[0050] The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0051] In some embodiments, the apparatus may further comprise a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle, and the tissue area, wherein the pressure relief valve may be positioned inside the compartment. In this embodiment, the compartment substantially bounded by the cover, the receptacle and the tissue area may be further bounded by the pressure relief valve. In other embodiments, the pressure relief valve may be positioned externally of the compartment. The fluid inlet and/or the fluid outlet may comprise an opening formed in the cover. The tissue area may comprise a wound area.

[0052] According to a further aspect, an apparatus for supplying fluid to a tissue area comprises a fluid delivery device configured to be positioned over a tissue site, wherein the fluid delivery device comprises a head portion that is configured to be positioned over the tissue area, a tail portion that is configured to extend away from the tissue area and a fluid inlet conduit arranged in fluid communication with the tail portion.

[0053] The fluid inlet conduit may be connected to the tail portion. The head portion may be in fluid communication with the tail portion such that the fluid inlet conduit is configured to supply fluid to the head portion via the tail portion. The tail portion may be longer than it is wide. The tail portion may have a width that is less than the width of the head portion

[0054] The fluid inlet conduit may pass through a wall of the tail portion. The wall through which the fluid inlet conduit may pass may be at an end of the tail portion that is furthest from the head portion.

[0055] The fluid delivery device may comprise a receptacle. The receptacle may be inflatable. In some embodiments, the receptacle is a bag. The receptacle may comprise one or more walls and is adapted to receive a fluid. The walls may comprise at least one section adapted to allow molecules within the fluid to move from inside of the receptacle to the tissue area. The one or more walls may be adapted to allow the molecules to move through the wall via diffusion. The one or more walls may be substantially pore-free such that molecules do not move through the wall via pore flow. The one or more walls may be substantially impermeable to bulk transport of liquid.

[0056] The apparatus may comprise a pressure spreading device. The fluid inlet conduit may be bonded to the pressure spreading device. The pressure spreading device may encapsulate at least a portion of the fluid inlet conduit between the fluid delivery device and a fluid source.

[0057] The pressure spreading device may be shaped to reduce a pressure exerted on the patient by the fluid inlet conduit. In some embodiments, the pressure spreading device may have a width that is greater than an external diameter of the fluid inlet conduit.

[0058] The tail portion and the pressure spreading device may be formed integrally with one another or they may comprise separate components. The tail portion of the fluid delivery device and the pressure spreading device may be bonded together. The pressure spreading device and the fluid delivery device may be made from the same material.

[0059] The pressure spreading device may have a generally elliptical cross-section. In some embodiments, it may have a cross-section that is shaped like a convex lens.

[0060] The apparatus may comprise a negative pressure compartment.

[0061] The tissue area may comprise a wound area. The wound area may comprise a wound and skin adjacent to the wound. The tissue site may comprise a wound. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0062] According to a further aspect, an apparatus for supplying fluid to a tissue area comprises a fluid delivery device configured to be positioned over a tissue site, a fluid inlet conduit for delivery of fluid to the fluid delivery device, and a pressure spreading device which encapsulates at least a portion of the fluid inlet conduit and is adjacent the fluid delivery device.

[0063] The fluid inlet conduit may be connected to the fluid delivery device. The fluid inlet conduit may be bonded to the pressure spreading device. The pressure spreading device may be shaped to reduce a pressure exerted on the patient by the fluid inlet conduit. The pressure spreading device may have a width that is greater than an external diameter of the fluid inlet conduit. For example, the width may be about 2 to 10 times greater than the external diameter, or about 3 to 9 times greater than the external diameter, or about 4 to 8 times greater than the external diameter, or about 5 to 7 times greater than the external diameter of the fluid inlet conduit.

[0064] The pressure spreading device and the fluid delivery device may be made from the same material. The pressure spreading device may have an elliptical cross-section. In some embodiments, the pressure spreading device may have a cross-section that is shaped like a convexlens.

[0065] The fluid delivery device may comprise a receptacle. The receptacle may be inflatable. In some embodiments, the receptacle is a bag. The receptacle may comprise one or more walls and is adapted to receive a fluid. The walls may comprise at least one section adapted to allow molecules within the fluid to move from inside of the receptacle to the tissue area. The one or more walls may be adapted to allow the molecules to move through the wall via diffusion. The one or more walls may be substantially pore-free such that molecules do not move through the wall via pore flow. The one or more walls may be substantially impermeable to bulk transport of liquid.

[0066] The receptacle may have a head portion that is configured to be positioned over the tissue area. The receptacle may have a tail portion that is configured to extend away from the tissue area. The fluid inlet conduit may be connected to the tail portion.

[0067] The head portion of the receptacle may be in fluid communication with the tail portion such that the fluid inlet conduit is configured to supply fluid to the head portion via the tail portion.

[0068] The tail portion may be longer than it is wide. The tail portion may have a width that is less than a width of the head portion when the receptacle is in a non-inflated configuration.

[0069] The tail portion of the fluid delivery device and the pressure spreading device may be formed integrally with one another or as separate components. The tail portion and the pressure spreading device may be bonded together.

[0070] The fluid inlet conduit may pass through a wall of the tail portion. The wall through which the fluid inlet conduit may pass may be at an end of the tail portion that is furthest from the head portion.

[0071] The apparatus may comprise a negative pressure compartment.

[0072] The tissue area may comprise a wound area. The wound area may comprise a wound and skin adjacent to the wound. The tissue site may comprise a wound. Thefluidmay comprise a gas, such as oxygen gas or carbon dioxide gas.

[0073] It will be appreciated that the various aspects, embodiments and features of the apparatus disclosed herein may be combinable with one another.

Brief Description of Drawings

[0074] One or more embodiments of the present disclosure will now be described by way of specific example(s) with reference to the accompanying drawings, in which:

[0075] Fig. 1 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area;

[0076] Fig. 2 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area;

[0077] Fig. 3 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area, having a fluid inlet conduit and first and second fluid outlet conduits;

[0078] Fig. 4 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area, having multiple receptacles;

[0079] Fig. 5 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area, having multiple receptacles and a manifold;

[0080] Fig. 6 is a cross-sectional schematic view of another embodiment of an apparatus for supplying fluid to a tissue area, having multiple receptacles and a manifold;

[0081] Fig. 7 is a cross-sectional schematic view of a further embodiment of an apparatus for supplying fluid to a tissue area;

[0082] Fig. 8 is a cross-sectional schematic view of an embodiment of an apparatus for supplying fluid to a tissue area, having a pressure relief valve;

[0083] Fig. 9 is a schematic plan view of an embodiment of the apparatus including a through-hole in the receptacle;

[0084] Fig. 10 is a schematic plan view of an embodiment of the apparatus including a plurality of through-holes in the receptacle;

[0085] Fig. 11 is a schematic plan view of an apparatus having multiple receptacles;

[0086] Fig. 12 is a cross-sectional schematic view of a further embodiment of the apparatus including fasteners;

[0087] Fig. 13 is a cross-sectional schematic view of a further embodiment of the apparatus including an absorbent material layer;

[0088] Fig. 14a and Fig. 14b are a schematic plan view and schematic cross-sectional view of an embodiment of the apparatus having combined fluid conduits;

[0089] Fig. 15a and Fig. 15b are a schematic plan view and schematic cross-sectional view of another embodiment of the apparatus having combined fluid conduits;

[0090] Fig. 16a and Fig. lb are a schematic plan view and schematic cross-sectional view of a further embodiment of the apparatus having combined fluid conduits;

[0091] Fig. 17a and Fig. 17b are a schematic plan view and schematic cross-sectional view of a still further embodiment of the apparatus having combined fluid conduits;

[0092] Fig. 18 is a schematic cross-sectional view of another apparatus for supplying fluid to a tissue area having a single receptacle;

[0093] Fig. 19 is a schematic cross-sectional view of the apparatus of Fig. 18, including a dressing;

[0094] Fig. 20 is a schematic cross-sectional view of another apparatus for supplying fluid to a tissue area having a single receptacle;

[0095] Fig. 21 is a schematic cross-sectional view of the apparatus of Fig. 20, including a dressing;

[0096] Fig. 22 is a schematic cross-sectional view of another apparatus for supplying fluid to a tissue area having multiple receptacles;

[0097] Fig. 23 is a schematic cross-sectional view of the apparatus of Fig. 22, including a dressing;

[0098] Fig. 24 is a schematic cross-sectional view of another apparatus for supplying fluid to a tissue, including a pressure relief valve;

[0099] Fig. 25 is a schematic cross-sectional view of the apparatus of Fig. 24, including a dressing;

[0100] Fig. 26 is a schematic plan view of a receptacle according to an embodiment of the apparatus;

[0101] Fig. 27 is a schematic cross-sectional view through the line A-A of Fig. 26; and

[0102] Fig. 28 is a schematic cross-sectional view of a further receptacle according to an embodiment of the apparatus.

Description of Embodiments

[0103] Figure 1 shows an embodiment of an apparatus for supplying fluid to a tissue area. The tissue area may include target tissue that is to be treated and an area of tissue surrounding the target tissue. The target tissue may include one or more of healthy tissue, recently healed wound tissue, scar tissue, muscle, bone and the like. The apparatus may supply fluid to tissue on an external surface of the patient (e.g. skin) or it may supply fluid to tissue on an internal surface of the patient (e.g. it may supply fluid to an intestinal wall or to the wall of an internal organ during surgery). One example of the tissue that the apparatus may be applied to is a wound. The embodiments described herein are described with reference to a wound. However, it will be appreciated that they are, in general, applicable to other tissue areas as described above.

[0104] The apparatus 100 includes a receptacle 10 that is positioned at a wound area 20, for example a chronic wound as may be found on a lower limb of a diabetic patient. The wound area 20 includes the wound 22 and an area of healthy skin 24 that surrounds the wound 22. The apparatus further includes a cover 30 that is positionable over the receptacle to form a compartment 35 that is substantially bounded by the cover 30, the receptacle 10, and the wound area 20. In some embodiments of the apparatus described in this disclosure, the compartment may also be bounded by additional components of the apparatus that may be present and still be substantially bounded by the cover 30, the receptacle 10 and the wound area 20. For example, in some embodiments of the disclosure described herein, the compartment may be further bounded by one or more fluid inlet conduits and/or fluid outlet conduits as will be described herein.

[0105] The receptacle 10 consists of an inflatable, hollow bag that is fluidly connectable to a fluid source 40 for inflating the receptacle 10 with a fluid. The receptacle 10 may be connected to a fluid inlet conduit 50 for delivery of the fluid from the fluid source 40 to the receptacle 10. The connection of the fluid source 40 to the fluid inlet conduit 50 is shown schematically in the Figures and may not be shown directly. It will be appreciated that one or more additional conduits (not shown) may be included in the connection between the fluid inlet conduit 50 and the fluid source 40.

[0106] In each of the embodiments described in this disclosure, the fluid may comprise a gas. For example, the fluid may comprise oxygen gas, carbon dioxide gas, and/or other therapeutic gases that may be beneficial in treating the wound and/or assisting the wound to heal. The fluid may also comprise a liquid, for example it may comprise water, water with molecularly dispersed substances, or saline solution. The fluid source 40 may be a gas source such as a wall source, oxygen or carbon dioxide bottle, oxygen or carbon dioxide concentrator, oxygen or carbon dioxide pump or the like, suitable to meet a predetermined concentration and/or pressure and/or flow rate of oxygen or other therapeutic fluid as will be described further below.

[0107] The receptacle 10 may be formed of one or more walls 15 of a flexible material. For example, it may be formed from a single wall or two or more walls attached together via heat sealing or otherwise. The receptacle 10 may contain oxygen gas, however other therapeutic fluids, for example carbon dioxide gas may also be used as described herein. The one or more walls 15 of the receptacle 10 has at least one section that is made from a material that is adapted to allow molecules within the fluid in the receptacle 10 to diffuse to outside of the receptacle 10. In some embodiments, the entire receptacle 10 may be formed of the material that allows molecules within the fluid in the receptacle to diffuse through it, whereas in other embodiments the receptacle 10 (other than the at least one section) may be made of a material of a different thickness to the material of the at least one section, or it may be made of a different material. The material section(s) may have a thin wall. The material may have a thickness of between approximately 20 micrometres and 150 micrometres, for example between approximately 30 micrometres and 130 micrometres, or between approximately 35 micrometres and 100 micrometres, or between approximately 40 micrometres and 80 micrometres, or between approximately 45 micrometres and 55 micrometres. In some embodiments, the wall thickness is approximately 50 micrometres. The thinness of the material allows the wall 15 of the receptacle 10 to be flexible. This flexibility may help to maximise the surface contact between the receptacle 10 and the wound area, by allowing the wall of the receptacle 10 to conform to the wound surface, regardless of the wound topology. The material section(s) may be made of a stretchable material (that may deform elastically). The material section(s) may stretch in response to the amount of fluid in the receptacle. The stretchable material may help to maximise the surface contact between the receptacle 10 and the wound area, by allowing the wall of the receptacle 10 to conform to the wound surface, regardless of the wound topology.

[0108] As used in this specification, the terms 'diffuse' and 'diffusion' refer to the process of molecular diffusion. Molecular diffusion is a process by which molecules within a fluid can pass from an upstream side to a downstream side of a material (e.g. a polymer film). Molecular diffusion involves three stages: 1) sorption - the molecules within the fluid on the upstream side of the material are adsorbed onto the upstream surface of the material and then absorbed into the material; 2) diffusion - the molecules diffuse through the material. The direction of diffusion is dependent on a concentration gradient of the molecules within the material. The diffusion stage may be facilitated by the opening and closing of free-volume elements in the material; 3) desorption - the molecules may be desorbed from the downstream surface of the material into the fluid on the downstream side of the material. If the fluid into which the molecules desorb is a gas, then the molecules may be in a gas phase, or dispersed in the gas, after desorption. If the fluid into which the molecules desorb is a liquid, then the molecules may be in a liquid phase, or dispersed in the liquid, after desorption. The molecules will not remain in a liquid phase or a gas phase throughout the diffusion stage. Instead, during this stage, the molecules are considered to be molecularly dispersed in the material. The number of molecules that pass from the upstream side to the downstream side per unit time via molecular diffusion may be a function of, for example: the partial pressures on the upstream and downstream sides, the concentrations on the upstream and downstream sides, the thickness of the material, and the area of the material through which the molecular diffusion can occur.

[0109] As used in this specification, the term 'pore' refers to pores through which fluid molecules may move from an upstream side towards a downstream side of a material (e.g. a porous foam). The movement of molecules through pores, from an upstream side towards a downstream side of a material, is known as pore flow. For molecules to pass completely through a material via pore flow alone, there must be one or more pores that provide a continuous pathway from the upstream side to the downstream side. When molecules move from the upstream side to the downstream side of a material via pore flow, they may remain in a particular phase (e.g. liquid or gas) throughout.

[0110] The material may be a membrane that is adapted to allow molecules within the fluid to diffuse through the membrane. The membrane may be hydrophobic. Alternatively the material can be treated so that it repels water. In some embodiments, the membrane is substantially pore-free. Accordingly, in those embodiments the membrane material may have no visible discontinuities or pores that are visible with an optical or electron microscope, for example a scanning electron microscope such as a Jeol IT300, at a resolution on the order of 1 micrometre. Transport of fluid through the membrane does not substantially take place via porosity of the membrane. The diffusion transport mechanism provides a more even distribution of fluid molecules diffusing from the receptacle to the wound area when compared with materials having micropores or porous membranes. This is because, some of the pores may become blocked, by exudate for example, causing an uneven distribution of molecules across the membrane. The substantially pore-free membrane helps to prevent wound exudate from clogging or entering the receptacle 10. However, transport by porosity may occasionally take place, for example, due to the possibility of manufacturing defects occurring in the membrane. The membrane is substantially impermeable to bulk transport of liquid, further helping to prevent exudate from entering the receptacle 10. The membrane can be hydrophobic.

[0111] Suitable materials for the membrane include any silicone liquid rubber, such as any one of, or a combination including, a liquid silicone rubber having a 70 Shore A hardness elastomer (Silopren@ LSR 4070 silicone from Momentive) or a 40 Shore A hardness elastomer (Silopren@ LSR 4840 silicone from Momentive); pre-formed silicone sheet or film; silicone hydrogel; multilayer, blown, LLDPE/CaCO3films, for example resin LLDP/CaCO3 from Reifenhauser (BF110, BF106); materials having silicone coatings; high consistency rubber silicone (HCR); KEG-2000-60-A/B (Shore A hardness of approximately 60) or KEG 2000-40-A/B (Shore A hardness of approximately 40) from Shin Etsu; and a copolymer that comprises polyethylene and poly(ethylene oxide).

[0112] In some embodiments, the membrane is made of a liquid silicone rubber having a 60 Shore A hardness that forms sheets having a thickness of 50 micrometres. In some embodiments, the membrane is made of a liquid silicone rubber having a 40 Shore A hardness that forms sheets having a thickness of 50 micrometres. These materials have been found to have suitable durability and suitable ability to hold their shape. The fluid inlet conduit 50 may also be made of this material. In this case, the fluid inlet conduit 50 may be integrally formed with the receptacle 10 or it may be connected to it via a seal. Alternatively, the fluid inlet conduit 50 may be made of soft, pliable material such as silicone tubing, for example Versilic© silicone tubing.

[0113] The gas supply to the receptacle 10 may be continuous or it may be intermittent, i.e. supplied periodically. The gas may have a concentration of up to 100%, for example 99% or % or 90% and/or a pressure of between about 6 mmHg and 50 mmHg above atmospheric pressure, for example between about 10 mmHg to 40 mmHg or about 20 mmHg to 30 mmHg.

[0114] The receptacle 10 may come in various sizes according to the size of the wound. When inflated it may have a spheroid, ovoid, cuboid or cylindrical shape. As seen in Figure 1, the receptacle 10 has a flattened ovoid cross-sectional shape, which provides a substantial wound-facing surface area 12 for contacting the wound when the receptacle is at least partially inflated. The wound facing surface 12 of the receptacle 10 is made of the membrane adapted to allow molecules to diffuse from the receptacle to the wound 22. The wound facing surface 12 of the receptacle 10 is pressed against the wound surface and forces exudate to move outwards to the periphery of the wound 22. The wound 'experiences' the highest pressure from the receptacle in the radial centre and the lowest pressure from the receptacle at the radial extreme due to the shape of the receptacle. This pressure gradient can force exudate to move outwards. Forcing the exudate to move outwards may help to prevent pooling of exudate between the wound facing surface 12 of the receptacle 10. Preventing this pooling may be beneficial as it may help to prevent exudate from impeding the movement of molecules from the inside of the receptacle to the wound. The receptacle configuration of Figure 1 also provides a substantially even distribution of fluid to the wound 22 as a result of the substantial area of the wound facing surface 12. The diffusion of the fluid molecules through the membrane adapted to allow molecules to diffuse from the receptacle 10 to the wound 22 further provides for a substantially even concentration of fluid being applied across the wound 22.

[0115] In the embodiment of Figure 2, the receptacle 10 is at least partially inflated and has an undulating surface that may conform particularly well to complex, three-dimensional wound surfaces such that a larger proportion of the wound 22 is contacted by the wound facing surface 12 of the membrane. The undulating surface may also help facilitate exudate flow away from the wound. This embodiment is described with reference to a wound. However, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure.

[0116] In some embodiments, the receptacle 10 may function as a fluid reservoir in which a volume of fluid may be stored. This can be beneficial if the fluid supply to the receptacle is interrupted, due, for example, to a disconnection of the fluid source 40 from the fluid inlet conduit 50 or a malfunction of the fluid source 40. In some embodiments, the receptacle 10 is filled with fluid to ensure a fluid supply to the wound 22 in the event of disruption of the fluid supply from the fluid source 40. The filling of the receptacle 10 may be carried out by a clinician prior to positioning the receptacle 10 at the wound area 20 of the patient or during use of the apparatus. Alternatively, the receptacles 10 may be pre-filled with the fluid during manufacture of the apparatus, for example at the site of manufacture.

[0117] As shown in Figure 1, embodiments of the receptacle 10 include a plurality of structures, for example microstructures 60, arranged on the wound facing surface 12 of the receptacle 10. Whilst the microstructures are shown arranged on the receptacle 10 of the embodiment of Figure 1, they may be used with any of the embodiments of the receptacle(s) described and illustrated in this disclosure. The microstructures are structures of microscale dimensions that are configured to contact the wound area 20 of the patient. The microstructures 60 may be made of the same material as the membrane adapted to allow molecules to diffuse from the receptacle 10 to the wound 22 of the receptacle 10. The microstructures 60 are positioned on and protrude from the wound facing surface 12. The microstructures may exert forces on the wound. These forces may result in micro-stresses that stretch the underlying cells and cause them to take on the same signalling pathways as those affected by growth factors. This can encourage cell growth. The molecules within the fluid in the receptacle 10 may diffuse through the membrane of the receptacle 10 and into the wound, and/or through the membrane of the receptacle, through the microstructures 60, and into the wound.

[0118] The microstructures 60 maybe of asemi-spherical, spherical, pyramidal, conical, or frustoconical shape, or have a trapezoidal, semi-circular or parabolic shape in profile, or may be formed from small dimples in the surface of the membrane. . Any corners or edges of the microstructures 60 may be rounded as sharp edges can cause damage to cells. The microstructures 60 may be formed as elongate structures having e.g. a semi-circular, parabolic or trapezoidal cross-sectional profile as described above, or they may comprise discrete structures, each having e.g. a pyramidal or semi-spherical or parabolic or conical or frustoconical shape. In some embodiments the microstructures 60 are configured in arrays. The microstructures 60 may have a base dimension, e.g. a width or a diameter of between approximately 100 to 400 micrometres, for example between approximately 250 to 350 micrometres, or between approximately 280 to 330 micrometres. The microstructures 60 may be spaced from one another at a distance of between about 0.5mm to 3mm between the bases of adjacent microstructures 60. The microstructures 60 may have a height dimension of between approximately 100 to 200 micrometres, for example between approximately 125 to 175 micrometres. In some embodiments, the microstructures may have a base dimension of approximately 310 micrometres and a height dimension of approximately 150 micrometres. The cells typically have a height dimension of between approximately 7 micrometres and 15 micrometres, for example 10 micrometres. It will be appreciated by the skilled person that the microstructures 60 illustrated in Fig. 1 are not to scale.

[0119] The cover 30 is configured to at least partially enclose the receptacle 10 to form a compartment 35 substantially bounded by the cover 30, the receptacle 10 and the wound area 20. In some embodiments, for example as shown in Fig. 1, the cover 30 is positionable over the receptacle 10 to fully enclose the receptacle 10 to form the compartment 35.

[0120] In some embodiments, the cover 30 consists of a wall or walls configured to enclose the receptacle 10 and to seal to the healthy skin 24 adjacent the wound 22. A seal 32 for this purpose may comprise an adhesive in the form of an adhesive bead or strip at a sealing surface of the cover 30 or it may be a suction seal. The cover 30 may include a layer of absorbent material 75, seen in Figure 13, such that any exudate from the wound that reaches the cover is absorbed into the layer of absorbent material 75. The absorbent material 75 may be a fibrous fabric. The absorbent material 75 may form part of the cover 30, or it may be provided as a separate layer for use with the cover 30. For example, the absorbent material 75 may be wrapped around a limb or other body part of the patient that has the wound. The cover 30 may be placed over the absorbent material 75. The absorbent layer 75 forms part of the cover 30 such that the compartment substantially bounded by the cover 30, the receptacle and the tissue area includes the absorbent layer 75. The absorbent material 75 may allow exudate to evaporate to the ambient environment. Alternatively, the cover 30 may be impermeable to the bulk flow of fluid. This arrangement is in contrast to some known solutions in which the absorbent layer is provided directly over the wound for collecting exudate. In these known solutions, the exudate may saturate and 'clog' the absorbent layer. If this occurs, it may impede movement of molecules from the inside of the receptacle to the wound surface, or lead to inconsistent and/or unevenly distributed application of the molecules to the wound surface. In addition to this, there is also a chance that pieces of the absorbent layer may end up in the wound (which may increase the chance of infection). Alternatively, as the wound heals, tissue can grow into the voids of the absorbent (e.g. foam) material. This may make it painful to remove the absorbent material. An advantage of the absorbent material forming part of the cover 30 or being provided for use with the cover 30 is that it avoids these issues, as it allows for absorption of the exudate into the absorbent material 75 away from the wound 22 and away from the receptacle 10. Even if exudate saturates or clogs the absorbent layer, the movement of molecules from the inside of the receptacle to the wound surface will not be impeded by the absorbent layer.

[0121] The cover 30 may be separate to the receptacle 10 or it may be combined with (i.e. connected to) the receptacle 10 to form a single dressing that can be placed at the wound area.

[0122] With reference to the embodiment of Figure 3, the cover 30 includes a first opening 34 through which the fluid inlet conduit 50 passes to enter the compartment 35 to provide fluid to the receptacle 10. The cover further includes a second opening 36 via which fluid in the receptacle 10 may exit the receptacle 10. The opening 36 receives a first fluid outlet conduit 52. The first fluid outlet conduit 52 is integral with or connected to the receptacle 10 and passes through the second opening 36. The cover 30 further includes a third opening 38 through which fluid in the compartment 35 may exit the compartment 35. A second fluid outlet conduit 54 is connected at the second opening 38 of the cover 30 for transporting fluid or other fluid out of the compartment 35. The first and second fluid outlet conduits 52, 54 may be made from soft, pliable material such as silicone tubing, for example Versilic© silicone tubing. In this embodiment, as described elsewhere in this disclosure, the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by the fluid inlet conduit and the first fluid outlet conduit.

[0123] In this embodiment, the at least one section of the wall 15 of the receptacle 10 may allow molecules within the fluid to diffuse from the receptacle 10 to the wound 22 or to pass from the receptacle 10 to the wound 22 via pore flow or it may allow the fluid to diffuse from the receptacle 10 to the wound 22 and to pass from the receptacle 10 to the wound 22 via pore flow. The receptacle 10 may include a plurality of the microstructures 60 arranged on the wound facing surface 12 of the receptacle 10. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0124] The provision of the fluid inlet conduit 50 and the fluid outlet conduit 52 in fluid communication with the receptacle 10 allows for circulation of fluid through the receptacle 10. Fluid enters the receptacle 10 via the fluid inlet conduit 50. Fluid exits the receptacle 10 via the second fluid outlet conduit 52. Fresh fluid can be cycled into and out of the receptacle 10 as shown schematically in Figure 3, either constantly or periodically. The cycling enables a fluid concentration, for example an oxygen gas concentration, within the receptacle 10 to be maintained at a desired level, even if nitrogen and/or other fluid molecules enter the receptacle through the membrane 15 of the receptacle 10. The cycling also enables the fluid, from which molecules diffuse through the wall 15 of the receptacle 10, or which passes through the wall 15 via pore flow, to be replenished. The fluid concentration may be precisely controlled via a controller, for example a controller of the fluid source 40. Additionally, other fluids, including drugs could be cycled through the receptacle 10 and applied to the wound 22 via diffusion through the wound facing surface 12.

[0125] The apparatus may include a negative pressure source 45 for drawing fluid out of the compartment 35. Negative pressure refers to a pressure below that of the ambient atmosphere around the patient. The pressure in the compartment 35 may be altered to be between approximately 50mmHg to 150mmHg or between approximately 80mmHg to 125mmHg or between 90mmHg to 1OmmHg below atmospheric pressure. The negative pressure source may be a pump. The second fluid outlet conduit 54 may connect the compartment 35 to the negative pressure source 45 at the third opening 38 of the cover 30. The connection of the negative pressure source 45 to the second fluid outlet conduit 54 is shown schematically in the Figures and may not be shown directly. It will be appreciated that one or more additional conduits (not shown) may be included in the connection between the second fluid outlet conduit 54 and the negative pressure source 45.

[0126] In use, the receptacle 10 is positioned on the wound 22 and may be held in place by the cover 30 operating as a negative pressure dressing. The cover 30 seals to the healthy skin 24 of the patient surrounding the wound 22 and, as the negative pressure source 45 draws fluid from the compartment 35, forms a negative pressure compartment enclosing the receptacle 10. The fluid inlet conduit 50 and/or the second fluid outlet conduit 54 may extend through the cover 30 or under an outer edge of the cover 30.

[0127] As shown in the embodiment of Figure 3, fluid maybe cycled through the receptacle at the same time as a negative pressure is applied to the compartment 35. The negative pressure is applied to the compartment 35 by the negative pressure source 45, via the second fluid conduit 54 connected to the cover 30 at the third opening 38. The fluid in the receptacle may diffuse through the membrane or pass through it via pore flow at the wound facing surface 12 of the receptacle 10 as the negative pressure is applied to the compartment 35.

[0128] This embodiment is described with reference to a wound. However, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure.

[0129] In the embodiments of Figures 1 and 2, the cover 30 includes only the first opening 34 and the third opening 38. In these embodiments, fluid is supplied into the receptacle 10 via the fluid inlet conduit 50 and exits the receptacle only via diffusion through the membrane adapted to allow molecules within the fluid to diffuse from the wound facing surface 12 of the receptacle 10. Simultaneously, a negative pressure may be applied to the compartment 35 via the second fluid outlet conduit 54 connected to the cover 30 at the third opening 38. In these embodiments, the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by the fluid inlet conduit 50. This arrangement of the apparatus 100 is advantageous over prior solutions that allow a therapeutic fluid (e.g. oxygen) and negative pressure to be applied to a wound simultaneously. Many of these existing solutions rely on an arrangement that, when sealed to the heathy skin surrounding a wound, defines a single compartment (a compartment bounded by the inside of the bandage and the wound area). Oxygen is pumped into the compartment while the fluid within the compartment is removed (by a negative pressure pump) to generate the negative pressure environment. One issue with these existing, single-compartment arrangements is that the negative pressure tends to draw oxygen out of the wound environment before it has a chance to contact the wound. Furthermore, as the negative pressure draws exudate from the wound and into the compartment, this exudate may impede the movement of molecules from the inside of the receptacle to the wound surface. The dual compartment arrangement of the apparatus 100 allows negative pressure to be applied to the wound and exudate to be removed into the compartment 35 and through the second fluid outlet conduit 54 without significantly affecting the movement of molecules from the receptacle 22, through the membrane, to the surface of the wound 22. The receptacle 10 of this embodiment may include a plurality of the microstructures 60 arranged on the wound facing surface 12 of the receptacle 10.

[0130] In some embodiments, shown in Figures 14 to 17, two or more of the fluid inlet conduit 50, the first fluid outlet conduit 52 and the second fluid outlet conduit 54 may be combined into a single conduit that passes through only a single opening 39 in the cover 30. For example, in Figure 14a and Figure 14b, the fluid inlet conduit 50 and the second fluid outlet conduit 54 may be arranged coaxially. Figure 14a shows the coaxial arrangement of the fluid inlet conduit 50 and the second fluid outlet conduit 54 in plan view. Figure 14b shows the coaxial arrangement of the conduits 50, 54 in use of the apparatus 100. Figure 15a and Figure 15b show another arrangement in which the fluid inlet conduit 50 and the second fluid outlet conduit 54 may be arranged adjacent one another to pass through the single opening 39 in the cover 30. In the arrangement of Figure 16a and Figure 16b, the apparatus includes the fluid inlet conduit 50, the first fluid outlet conduit 52 and the second fluid outlet conduit 54, arranged adjacent one another as a combined conduit that passes through the single opening 39. In Figures 17a and 17b, the fluid inlet conduit 50, first fluid outlet conduit 52 and second fluid outlet conduit 54 are arranged coaxially. These arrangements may improve the seal between the apparatus 100 and the skin of the patient or other tissue surface, due to multiple conduits passing through a single opening in the cover rather than through multiple openings. The single opening 39 provides a larger cover surface area for sealing against the tissue of the patient than would be the case with the first, second and third openings 34, 36, 38.

[0131] In the embodiments of Figures I to 6 and also Figure 8 and Figures 12 to 17, the cover 30 and the receptacle 10 do not share any common walls; they are separate components and the walls of the receptacle 10 and the cover 30 are independent of one another. The cover may be connected to the receptacle 10 via the fluid inlet conduit 50, at the opening 34. The cover 30 may also be connected to the receptacle 10 via the first fluid outlet conduit 52 at the opening 36. These one or two connection points may be the only points of connection between the receptacle 10 and the cover 30. This minimal connection between the receptacle and the cover 30 enables the receptacle 10 to be movable within the compartment 35 while also allowing exudate to move out of the wound 22, which may help the receptacle 10 to conform to wounds 22 having a complex geometry and/or topology. In each of these embodiments, the receptacle(s) 10 may include a plurality of the microstructures 60 arranged on the wound facing surface 12 of the receptacle(s) 10.

[0132] In some embodiments of the apparatus 100, the cover 30 maybe formed from wrapping a dressing, for example a compression bandage around a body part, for example a limb, of the patient and over the receptacle 10. The compression bandage holds the receptacle in place on the wound 22 and can absorb exudate and/or allow evaporation of exudate. The compression bandage material allows the bulk transport of gases, however it will be appreciated that it may be wrapped about the patient forming enough layers that it provides a substantial barrier to the bulk flow of gases. The fluid inlet conduit 50, first fluid outlet conduit 52 and/or the second fluid outlet conduit 54 may not be connected to the compression bandage but may protrude from a gap in the wrapped layers. In a variation of this embodiment, the dressing may be an adhesive dressing that adheres to the healthy skin of the patient over the receptacle 10. This embodiment may or may not utilise the negative pressure source 45 to form a negative pressure compartment. Whilst this embodiment is described with reference to a wound, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure. In this embodiment, the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by one or more of the fluid inlet conduit 50 and the first fluid outlet conduit 52.

[0133] Figure 4 shows a further embodiment of the apparatus 100 that includes a plurality of the receptacles 10 positioned at the wound area 20. The plurality of receptacles may be distributed over the wound 22 as is also shown schematically in the plan view of Figure 11. In the embodiments of Figure 4 and Figure 11, the at least one section of the wall 15 of the multiple receptacles 10 may allow molecules within the fluid to diffuse from the multiple receptacles 10 to the wound 22 or to pass from the multiple receptacles 10 to the wound 22 via pore flow or to allow the fluid to diffuse from the multiple receptacles 10 to the wound 22 and to pass from the multiple receptacles 10 to the wound 22 via pore flow. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0134] Multiple receptacles 10 can provide additional conformability to the wound 22 for complex and/or varying wound topologies. For example, if a wound 22 is small or deep, multiple receptacles 10 may be more easily manipulated to optimise delivery of therapeutic fluid and/or negative pressure therapy. Accordingly, if a wound 22 is deep and/or has an irregular surface, it may be possible to achieve greater surface area contact between the section(s) of the wall(s) 15 through which the molecules can diffuse or pass via pore flow and the wound surface by using multiple receptacles 10, relative to the contact that could be achieved using one receptacle 10. A large amount of surface area contact can be beneficial as it can result in a more even distribution of therapeutic molecules to the wound surface.

[0135] Multiple receptacles 10 may also allow for more localised wound healing. For example, if some parts of a wound heal faster than others, one or more of the receptacles 10 can be positioned to promote healing of a wound region that is less healed rather than remaining at the more healed parts. Each receptacle 10 is moveable within the compartment independently of any of the other receptacles 10. Each receptacle 10 may include a plurality of the microstructures 60 arranged on the wound facing surface 12 of the receptacle 10.

[0136] As shown in Figure 4, each of the receptacles 10 has its own fluid inlet conduit 50 associated with it. In the embodiment of Figure 4, each of the fluid inlet conduits passes through a separate respective first opening 34 in the cover 30, for connection to a respective separate fluid supply or fluid source. This arrangement allows different fluids to be provided in different receptacles for variable, customisable control of fluid molecule delivery over the wound area 20. It will be appreciated that any reasonable number of multiple receptacles 10 and fluid inlet conduits 50 may be positioned at the wound area 20 and that the number of receptacles is not limited to the number shown in Figure 4. For example, the number of receptacles 10 may depend on the surface area of the wound 22. Examples include from two, three, four and all numbers of receptacles that may be required to treat the tissue area concerned. Whilst this embodiment is described with reference to a wound, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure. In this embodiment, the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by the each of the fluid inlet conduits 50.

[0137] In the embodiments of Figure 5 and Figure 6, the fluid inlet conduits 50 are connected together in fluid communication with one another via a manifold 80, the manifold being supplied with fluid via a single fluid supply conduit 85. The manifold 80 joins together the three fluid inlet conduits 50 shown in Figure 5 inside the compartment 35. The manifold joins together the three fluid inlet conduits 50 shown in Figure 6 outside the compartment 35. The Figure 5 arrangement may improve sealing of the cover 30 against the skin when compared with the embodiment of Figure 6, as it requires fewer openings in the cover 30. It will be appreciated that any reasonable number of multiple receptacles 10 and fluid inlet conduits 50 may be joined together at the manifold 80 and that the number of receptacles is not limited to the number shown in Figure 5 and Figure 6.. For example, the number of receptacles 10 may depend on the surface area of the wound 22. Examples include from two, three, four and all numbers of receptacles that may be required to treat the tissue area concerned. The single fluid supply conduit 85 passes through the first opening 34 in the cover for receiving fluid therein from a single fluid source 40. The manifold may include a valve (not shown) on each fluid inlet conduit 50 for individual control of fluid flow through the respective fluid inlet conduits 50. Although not shown in Figure 5, respective first fluid outlet conduits 52 may be used to cycle fluid through the fluid receptacles 10 and to exit the receptacles 10 via the respective first fluid outlet conduits 52. In these embodiments, the compartment substantially bounded by the cover 30, the receptacles 10 and the tissue area is further bounded by the fluid inlet conduits 50, the manifold 80 and the fluid supply conduit , and the respective fluid outlet conduits 52 if present.

[0138] In the embodiment of Figure 6, the manifold 80 joins together the three fluid inlet conduits 50 outside of the compartment 35. In these embodiments, the compartment substantially bounded by the cover 30, the receptacles 10 and the tissue area is further bounded by the fluid inlet conduits 50. It will be appreciated that any reasonable number of receptacles 10 and fluid inlet conduits 50 may be joined together at the manifold 80. The three fluid inlet conduits 50 pass through respective first openings 34 in the cover 30 for receiving fluid therein from a single fluid source 40. The manifold may include a valve (not shown) on each fluid inlet conduit 50 for individual control of fluid flow through the respective fluid inlet conduits 50. Although not shown in Figure 6, respective first fluid outlet conduits 52 may be used to cycle fluid through the receptacles 10. The fluid may enter the receptacles 10 via the fluid supply conduit 85 and the respective fluid inlet conduits 50 and exit the receptacles 10 via the respective first fluid outlet conduits 52.

[0139] It is noted that Figures 5 and 6 are schematic illustrations of the manifold 80, fluid inlet conduits 50 and fluid supply conduit 85. The manifold 80, fluid inlet conduits 50 and fluid supply conduit 85 may be made from soft, pliable material such as silicone tubing, for example Versilic© silicone tubing. They may be formed integrally with the receptacles 10, so that they are conformable and comfortable against the wound 22. This embodiment is described with reference to a wound. However, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure.

[0140] Fig. 7 shows an apparatus 200 in which the receptacle 10 is not enclosed within the negative pressure compartment 35. The receptacle 10 may be formed from two sheets of material, for example a wound facing sheet 212 and a cover sheet 230 that are pressed and sealed together at the edges of the receptacle 10. The excess pressed material around the receptacle 10 forms the cover 230 that includes the seal 32 for sealing to the healthy skin 24 of the patient around the wound 22 or other tissue area. The two sheets of material 212, 230 that are pressed and sealed together may be made of the same material. For example, the wound facing sheet 212 and the cover sheet 230 may both be made from the membrane that allows molecules to pass through it. Alternatively, the two sheets that are pressed and sealed together may be made of different material. For example, the wound facing sheet 212 may be made from the membrane that allows molecules to pass through it, whereas the cover sheet 230 may not allow molecules to pass via diffusion or via pore flow, or it may allow molecules within the fluid to both diffuse from the receptacle 210 to the wound 22 and to pass from the receptacle 210 to the wound 22 via pore flow. If the cover sheet 230 is made from the membrane that allows molecules to pass through, then molecules may be able to move from the compartment 35 to the outside of the cover. Alternatively, the cover 230 could be added, for example glued, onto the receptacle 10 after the receptacle has been formed. The apparatus 200 may further comprise a negative pressure compartment 35 substantially bounded by the cover 230, the receptacle 10 and the wound area 20. In each of these alternative constructions, the negative pressure compartment 35 is substantially bounded by the cover 230, the receptacle 10 and the wound area 20. In this embodiment, the fluid may enter the receptacle via the fluid inlet conduit 50 and, although not shown in Figure 7, it may also be cycled through the receptacle 10 and exit the receptacle 10 via the first fluid outlet 52. The negative pressure compartment 35 is formed by connecting the third opening 38 in the cover 230 to the negative pressure source 45. Alternatively, this embodiment may be used without a negative pressure compartment, in which case the first fluid outlet conduit 54 and the negative pressure source 45 need not be included. The receptacle 10 may include a plurality of the microstructures 60 arranged on the wound facing sheet 212 of the receptacle 10. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas. The apparatus 200 may require less material to manufacture than the apparatus 100.

[0141] If a fluid source 40 (e.g. a pump) or its associated controller malfunctions, the pressure within the associated oxygen compartment(s) may increase to an undesirable level. This could cause the receptacle(s) 10 to rupture. In some embodiments, the apparatus 100 includes a pressure relief valve 70 that can be configured to open to relieve pressure if the pressure within the receptacle(s) 10 exceeds a threshold value. As seen in Figure 8, the pressure relief valve 70 may be connected to the fluid inlet conduit 50 either at a wall of the fluid inlet conduit 50 or at a wall of a branch line 72 extending from and in fluid communication with the fluid inlet conduit 50. The pressure relief valve 70 may be positioned outside of the compartment 35 formed by the cover 30 (as shown in Figure 8) or inside the compartment 35 formed by the cover 30 (not shown). When open, the pressure relief valve 70 may exhaust fluid to the ambient environment (if positioned outside of the cover 30), or exhaust fluid into the compartment formed by the cover 30 (if positioned inside of the compartment 35). In this embodiment, the compartment substantially bounded by the cover 30, the receptacle 10 and the tissue area is further bounded by the fluid inlet conduit 50 and the pressure relief valve, if present inside the cover 30.

[0142] In the embodiment of Figures 7 and 8, the at least one section of the wall 15 of the receptacle 10 may allow molecules within the fluid to diffuse from the receptacle 10 to the wound 22 or to pass from the receptacle 10 to the wound 22 via pore flow, or it may allow molecules within the fluid to both diffuse from the receptacle 10 to the wound 22 and to pass from the receptacle 10 to the wound 22 via pore flow. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0143] Figures 9 and 10 show embodiments of the apparatus 100 in which the receptacle 10 has a substantially annular or doughnut shape in plan view so as to include a through-hole 25.

In use of the apparatus 100, the through-hole 25 provides an additional path for exudate to flow away from the wound surface. It provides additional areas of fluid communication between the wound 22 and the cover 30 or the absorbent layer 75 of the cover 30. The through hole 25 may therefore help to facilitate the flow of exudate away from the wound 22, particularly when the compartment 35 is subject to a negative pressure to form a negative pressure compartment. In the embodiment of Figure 10, the receptacle 10 includes multiple through-holes 25, providing multiple additional paths for exudate to flow from the wound surface, which may further increase the flow of exudate away from the wound 22. These embodiments are described with reference to a wound, and its effect may be most advantageous when used at a wound. However, it will be appreciated that it is, in general, applicable to other tissue areas as described elsewhere in this disclosure. The receptacle 10 may include a plurality of the microstructures 60 arranged on the wound facing surface 12 (not shown in the plan views of Figures 9 and 10) of the receptacle 10.

[0144] The one or more receptacles 10 are movable by a clinician when being positioned on the wound area 20 on the patient and also in situ, in response to patient movement. However, in some circumstances it may be required to secure the receptacles in place. The apparatus 100 may further include one or more fasteners 80 for securing the receptacle(s) 10 in place at the wound area 20 once they are positioned. The fastener 80 may comprise adhesive, such as adhesive tape as schematically shown in Figure 12 and may be used to secure the receptacle 10 and/or one or more of the conduits 50, 52 (seen in Figure 3), 54 to the healthy skin of the patient 24 or to the cover 30. Securing the receptacle 10 and/or one or more the conduits 50, 52, 54 in place may reduce movement of the components within the wound 22.

[0145] Figures 18 to 25 show embodiments of the apparatus 300 that do not include a negative pressure compartment. These embodiments are described with reference to a wound. However, it will be appreciated that they are, in general, applicable to other tissue areas as described elsewhere in this disclosure The components of these embodiments are as described in respect of the apparatus 100, 200 and like components are given like reference numbers. In each of these embodiments, as with the other embodiments disclosed herein, the fluid may comprise a gas, such as oxygen gas or carbon dioxide gas. In its simplest form as shown in Figure 18, the apparatus 300 has a receptacle 10 and a fluid inlet conduit 50 through which fluid is introduced into the receptacle 10 from a fluid source 40. The receptacle 10 is formed of one or more walls 15 having at least one section made of the membrane adapted to allow molecules within the fluid to diffuse from the receptacle 10 to the wound area 20. The receptacle 10 is placed in contact with the wound 22, with the wound facing surface 12 of the receptacle 10 facing the wound 22. In the embodiment of Figure 19, an optional cover 30 in the form of a bandage may be wrapped around the body part containing the wound 22 such that it is wrapped over the receptacle 10 to provide pressure to the receptacle 10 and press it into contact with the wound 22. The bandage 30 contacts the healthy skin 24 of the patient that surrounds the wound at the wound area 20. An optional adhesive seal 32 may be used to fasten the bandage 30 to the healthy skin 24 to keep the bandage 30 in place. Where the bandage 30 is used, the fluid inlet conduit 50 may pass through the opening 34 that is formed in between adjacent wrappings of the bandage 30. In this embodiment, the compartment substantially bounded by the bandage 30, the receptacle 10 and the tissue area may be further bounded by the fluid inlet conduit 50.

[0146] Figure 20 shows an embodiment that is very similar to that of Figure 18, with the addition of the first fluid outlet conduit 52. Accordingly, the fluid that enters the receptacle through the fluid inlet conduit 50 may cycle through the receptacle and exit the receptacle through the first fluid outlet conduit 52. In Figure 21, as with the embodiment of Figure 19, the optional bandage 30 may be wrapped around the body part of the patient having the wound 22 and around the receptacle 10 placed on the wound 22. An optional adhesive seal 32 may be used to fasten the bandage 30 to the healthy skin 24 to keep the bandage 30 in place. Where the bandage 30 is used, the fluid inlet conduit 50 may pass through the opening 34 that is formed in between adjacent wrappings of the bandage 30. . In this embodiment, the compartment substantially bounded by the cover 30, the receptacle 10 and the tissue area may be further bounded by the fluid inlet conduit 50.

[0147] Figure 22 shows an arrangement that has multiple receptacles 10, in this case three receptacles. As with the apparatus 100, the number of receptacles 10 shown in Figure 22 is non-limiting and any reasonable number of receptacles 10 may be used depending on the area of the wound surface. Each receptacle 10 has a respective fluid inlet conduit 50 that is supplied with the fluid from the fluid source 40. The receptacles 10 are independent of one another and may be placed on the wound 22 where fluid is required. The receptacles 10 may be moved from time to time to treat other parts of the wound 22, for example a part that is not healing as quickly. Figure 23 shows this arrangement with the optional bandage 30 wrapped around the body part of the patient having the wound 22 and around the receptacles 10. The optional adhesive seal 32 may be used to fasten the bandage 30 to the healthy skin 24 to keep the bandage 30 in place. Where the bandage 30 is used, the respective fluid inlet conduits 50 may pass through respective openings 34 that are formed in between adjacent wrappings of the bandage 30. In some embodiments, the respective fluid inlet conduits 50 may pass through a single opening 34. In this embodiment, the compartment substantially bounded by the cover 30, the receptacle 10 and the tissue area may be further bounded by the fluid inlet conduits 50.

[0148] In the embodiments of Figures 22 and 23, the at least one section of the wall 15 of the receptacle 10 may allow molecules within the fluid to diffuse from the receptacles 10 to the wound 22 or to pass from the receptacles 10 to the wound 22 via pore flow, or it may allow molecules within the fluid to both diffuse from the receptacle 10 to the wound 22 and to pass from the receptacle 10 to the wound 22 via pore flow.

[0149] Figures 24 and 25 show variations of the arrangements of Figures 18 and 19 that include a pressure relief valve 70 either in the fluid inlet conduit 50 or in a branch line 72 of the fluid inlet conduit 50 as shown in Figures 24 and 25. In the embodiments of Figures 24 and 25, the at least one section of the wall 15 of the receptacle 10 may allow molecules within the fluid to diffuse from the receptacle 10 to the wound 22 or to pass from the receptacle 10 to the wound 22 via pore flow, or it may allow molecules within the fluid to both diffuse from the receptacle 10 to the wound 22 and to pass from the receptacle 10 to the wound 22 via pore flow. The arrangements are otherwise identical to the arrangements of Figures 18 and 19. In the embodiment of Figure 25, the compartment substantially bounded by the cover 30, the receptacle 10 and the tissue area may be further bounded by the fluid inlet conduit 50, the branch line 72 if present and the pressure relief valve 70.

[0150] In each of the embodiments of Figures 18 to 25, the receptacle(s) may include a plurality of microstructures 60 arranged on the wound facing surface 12 of the receptacle 10.

[0151] As discussed elsewhere in this disclosure, some of the dressings that cover the receptacle(s) 10 may press the receptacle 10 against the wound 22 and the healthy tissue 24 around the wound. Such dressings may also press some length of the fluid inlet conduit 50 or first fluid outlet conduit 52 connected to the receptacle 10 against the healthy tissue 24 around the wound 22 and even the wound 22 itself, depending on the size and position of the receptacle 10 relative to the wound 22. When the outer diameter of the conduits 50, 52 is small, for example 5 mm or less, the patient may find it uncomfortable to have the conduit 50, 52 pressed against them in this way. Furthermore, when the apparatus 100, 200, 300 is removed, the patient may be left with a temporary yet uncomfortable indentation in the shape of the conduit 50, 52. Figure 26 shows a schematic plan view of a variation of a receptacle 110 that is similar to the receptacle 10 in that it has a generally circular shaped head portion 93 that is placed over the wound 22 and further includes an additional tail portion 90 that is formed integrally with and extends from the generally circular shaped head portion 93. The tail portion 90 has a generally elongate rectangular shape when viewed in plan view and it is inflatable with the circular head portion 93 of the receptacle 110. The tail portion 90 may be longer than it is wide. The tail portion 90 may have a width that is less than the width of the head portion 93. The fluid inlet conduit 50 connects to a distal end wall 92 of the tail portion that is furthest from the head portion 93 such that it is in fluid communication with the tail portion 90. The fluid inlet conduit 50 is configured to supply fluid to the head portion 93 via the tail portion 90.

[0152] The tail portion 90 may extend beyond the wound 22 such that the interface between the fluid inlet conduit 50 and the receptacle 110 is spaced apart from the wound surface, reducing the likelihood of the fluid inlet conduit 50 being pressed into the wound or other tissue site of the patient by the bandage 30 or other dressing. Furthermore, the tail portion 90 may extend beyond the wound 22 such that the interface between the fluid inlet conduit 50 and the receptacle 110 is beyond the pressing force of the bandage 30 or other dressing, reducing the likelihood of the fluid inlet conduit 50 being pressed into the tissue of the patient by the bandage 30 or other dressing. In cases where the pressing force includes a portion of the tail portion 90 having the fluid inlet conduit 50, the pressing force may press the tail portion 90 against the patient rather than the fluid inlet conduit 50. This will be more comfortable for the patient. Whilst not shown in Figure 26, a fluid outlet conduit 52 may also be attached to the distal edge 92 of the tail 90. The receptacle 110 may be inflatable. In some embodiments, the receptacle 110 is a bag. The receptacle 110 may comprise one or more walls and is adapted to receive a fluid. The one or more walls may comprise at least one section adapted to allow molecules within the fluid to move from inside of the receptacle 110 to the tissue area. The one or more walls may be adapted to allow the molecules to move through the wall via diffusion. The one or more walls may be substantially pore-free such that molecules do not move through the wall via pore flow. The one or more walls may be substantially impermeable to bulk transport of liquid. The receptacle 110 may include a plurality of microstructures 60 arranged on a wound facing surface 12 of the receptacle 110. All other features of the receptacle 110 are the same as for the receptacle 10. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0153] Furthermore, as shown in Figures 26 and 27, the fluid inlet conduit 50 is encapsulated in a pressure spreading device 95 that is adjacent the receptacle 110. The pressure spreading device 95 is a silicone component that is moulded with the fluid inlet conduit 50 so as to surround it, as shown in the cross-sectional view of Figure 27. The pressure spreading device 95 spreads the load of the fluid inlet conduit 50 over a greater portion of the healthy skin 24 of the patient adjacent the wound 22 to reduce indentation during and after use of the receptacle 110.

[0154] The fluid inlet conduit may be bonded to the pressure spreading device. The pressure spreading device may encapsulate at least a portion of the fluid inlet conduit between the fluid delivery device and a fluid source. The pressure spreading device 95 may be shaped to reduce a pressure exerted on the patient by the fluid inlet conduit 50. In some embodiments, the pressure spreading device 95 may have a width that is greater than an external diameter of the fluid inlet conduit 50. For example, the width may be about 2 to 10 times greater than the external diameter, or about 3 to 9 times greater than the external diameter, or about 4 to 8 times greater than the external diameter, or about 5 to 7 times greater than the external diameter of the fluid inlet conduit.

[0155] The tail portion 90 and the pressure spreading device 95 maybe formed integrally with one another or they may comprise separate components. The tail portion 90 and the pressure spreading device 95 may be bonded together. The pressure spreading device 95 and the receptacle 110 may be made from the same material. The pressure spreading device 95 may have a generally elliptical cross-section. In some embodiments, it may have a cross section that is shaped like a convex lens as shown in Figure 27. The fluid inlet conduit 50 may be bonded to the pressure spreading device 95.

[0156] Figure 28 shows a further variation of the receptacle 210 that is formed to have an elongated tubular shape through which fluid may be flushed. The receptacle 210 has a fluid inlet conduit 50 at one end of the elongate tube shape, for admission of fluid into the receptacle 210. It also has a first fluid outlet conduit 52 through which fluid may exit the receptacle as with other embodiments of the receptacle 210. All other features of the receptacle 210 are the same as for the receptacle 10. This embodiment of the receptacle 210 may be particularly suitable for use on wounds or other tissue surfaces of a certain shape, for example elongate and/or narrow wound or other tissue area shapes. The receptacle 210 may include a plurality of microstructures 60 arranged on the wound facing surface 12 of the receptacle 10. The fluid may comprise a gas, such as oxygen gas or carbon dioxide gas.

[0157] In all embodiments of the apparatus 100, 200, 300, the fluid source 40 may be controlled to maintain a set pressure in the receptacle 10. That is, the controller may compensate over time for loss of fluid from the receptacle 10 due to e.g. fluid diffusion out of the receptacle 10 to the wound facing surface 12. As such, the section of the wall 15 or the entire wall 15 that is made of the membrane experiences an even pressure, which results in an even pressure of fluid applied at the wound 22.

[0158] The apparatus disclosed herein may be provided in various kit forms. For example, where the cover 30 is in the form of a compression bandage, the kit may comprise one or more receptacles 10 and the compression bandage. The kit may further comprise a fluid source 40, for example a portable oxygen source such as an oxygen bottle. Another kit may include one or more receptacles 10 and instructions to a user to apply a compression bandage for use with the one or more receptacles 10. A further kit may include one or more receptacles and a fluid source, for example a portable oxygen source such as an oxygen bottle. The receptacles 10 may be supplied with one or more of the fluid inlet conduit 50 and the pressure relief valve 70.

[0159] Where the cover 30 is in the form of an adhesive dressing, the kit may comprise one or more of the receptacles 10 and the adhesive dressing. The kit may further comprise a fluid source 40, for example a portable oxygen source such as an oxygen bottle. In one form, the kit may comprise one or more of the receptacles 10. In each of the kits, the receptacles 10 may be supplied with one or more of the fluid inlet conduit 50 and the pressure relief valve 70. A further kit may include a sealing cover 30 and a negative pressure source 45, for example a diaphragm or peristaltic pump. A canister (not shown) may also be supplied for attachment to the pump 45 for exudate collection.

[0160] It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

CLAIMS:

1. An apparatus for supplying fluid to tissue of a patient, the apparatus comprising:

an inflatable receptacle positionable at a tissue area, the receptacle comprising one or more walls and being adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area; and

a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the tissue area.

2. The apparatus of claim 1, wherein the receptacle is moveable within the compartment bounded by the cover, the receptacle and the tissue area.

3. An apparatus for supplying fluid to a tissue area, the apparatus comprising:

a receptacle positionable at a tissue area, the receptacle comprising one or more walls and being adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area; and

a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the tissue area,

wherein the receptacle is moveable within the compartment substantially bounded by the cover, the receptacle and the tissue area.

4. The apparatus of claim 3, wherein the receptacle is inflatable.

5. The apparatus of any one of claims 1 to 4, wherein the receptacle is in the form of a bag.

6. The apparatus of any one of the preceding claims, wherein the receptacle is configured to contact the tissue area.

7. The apparatus of any one of the preceding claims, wherein at least the at least one section of the receptacle is conformable with a surface of the tissue area.

8. The apparatus of any one of the preceding claims, wherein the one or more walls of the receptacle are adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

9. The apparatus of any one of the preceding claims, wherein the at least one section and/or the one or more walls comprise a membrane.

10. The apparatus of any one of the preceding claims, wherein the at least one section of the receptacle has an undulating outer surface when at least partially inflated.

11. The apparatus of any one of the preceding claims, wherein the at least one section of the receptacle comprises a stretchable material.

12. The apparatus of any one of the preceding claims, wherein the receptacle is connected to the cover at a single connection point or at two connection points.

13. The apparatus of any one of the preceding claims, wherein the apparatus further comprises a fluid inlet conduit arranged in fluid communication with the receptacle for delivery of fluid to the receptacle.

14. The apparatus of claim 13, wherein the cover has a first opening through which the fluid inlet conduit passes or to which the fluid inlet conduit is connected.

15. The apparatus of claim 13 or claim 14, wherein the receptacle is coupled to the cover via the fluid inlet conduit.

16. The apparatus of claim 15, wherein the compartment is further bounded by the fluid inlet conduit.

17. The apparatus of any one of the preceding claims, further comprising a fastener for securing the receptacle in place at the tissue area.

18. The apparatus of claim 17, wherein the fastener comprises adhesive.

19. The apparatus of any one of claim 13 or claim 14 or claim 15, wherein the fluid inlet conduit includes a pressure relief valve.

20. The apparatus of any one of the preceding claims, wherein the cover comprises one or more walls and wherein the one or more walls of the cover are independent of the one or more walls of the receptacle.

21. The apparatus of any one of claims 1 to 19, wherein the receptacle and the cover share a common wall.

22. The apparatus of any one of the preceding claims, wherein the receptacle is configured to receive fluid during use of the apparatus.

23. The apparatus of any one of claims 1 to 21, wherein the receptacle is pre-filled with the fluid.

24. The apparatus of any one of the preceding claims, wherein the one or more walls of the receptacle may define one or more through-holes through the receptacle.

25. The apparatus of any one of the preceding claims, including a plurality of the receptacles.

26. The apparatus of any one of the preceding claims, further comprising structures associated with the at least one section of the receptacle, the structures being configured to contact the tissue area.

27. The apparatus of claim 26, wherein the structures are configured for encouraging cell growth.

28. The apparatus of claim 26, wherein the structures are microstructures.

29. The apparatus of claim 27, wherein the microstructures comprise formations which protrude from the one or more walls of the receptacle.

30. The apparatus of claim 27 or claim 28, wherein molecules diffuse through the at least one section of the receptacle and the microstructures into the tissue area.

31. The apparatus of claim 28 or claim 29, wherein the microstructures protrude from a tissue facing surface of the one or more walls of the receptacle.

32. The apparatus of any one of claims 28 to 30, wherein the formations have one or more of a parabolic, trapezoidal, semi-spherical, spherical, pyramidal, conical, or frustoconical shape.

33. The apparatus of any one of claims 28 to 31, wherein the microstructures have rounded edges.

34. The apparatus of claim 9, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is substantially pore-free

. 35. The apparatus of claim 33, wherein the membrane comprises substantially no discontinuities or pores that are visible with an optical or electron microscope at a specified resolution.

36. The apparatus of claim 34, wherein the specified resolution is on the order of 1 micrometre.

37. The apparatus of any one of claims 33 to 35, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area comprises at least one of the following: liquid silicone rubber, pre-formed silicone sheet, silicone hydrogel, linear low density polyethylene treated with calcium carbonate, silicone coatings, and high consistency rubber silicone.

38. The apparatus of any one of claims 32 to 36, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is configured to contact the tissue area.

39. The apparatus of any one of claims 33 to 37, wherein the one or more walls of the receptacle, other than the at least one section, comprise a material adapted to allow molecules to pass through via molecular diffusion at only a negligible rate of diffusion.

40. The apparatus of any one of the preceding claims, wherein the at least one section is conformable to the surface of the tissue area.

41. The apparatus of any one of the preceding claims, wherein the at least one section has a wall thickness of between about 20 micrometres and 150 micrometres, or between about micrometres and 130 micrometres, or between about 35 micrometres and 100 micrometres, or between about 40 micrometres and 80 micrometres or between about 45 micrometres and micrometres.

42. The apparatus of claim 40 or claim 41, wherein the at least one section has a wall thickness of approximately 50 micrometres.

43. The apparatus of any one of claims 33 to 41, wherein the membrane is impermeable to bulk transport of liquid.

44. The apparatus of claim 42 wherein molecules within a liquid pass from one side of the membrane to the other via diffusion.

45. The apparatus of any one of the preceding claims, wherein the at least one section of the one or more walls of the receptacle are hydrophobic.

46. The apparatus of any one of the preceding claims, wherein the cover is configured to secure the receptacle to the tissue area.

47. The apparatus of any one of the preceding claims, wherein the cover is configured to press the receptacle onto or into the tissue area.

48. The apparatus of any one of the preceding claims, wherein the cover comprises a dressing.

49. The apparatus of claim 48, wherein the dressing is a bandage is wrapped around a body part of the patient to form the cover.

50. The apparatus of claim 48, wherein the tissue area comprises a wound area, and wherein the cover comprises an absorbent material for absorbing exudate from the wound area.

51. The apparatus of claim 49, wherein the absorbent material is placed upon or within the wound area of a patient and the bandage is wrapped over the absorbent material to form the cover.

52. The apparatus of claim 46, wherein the cover comprises an adhesive dressing.

53. The apparatus of any one of claims 47 to 50, wherein the bandage is a compression bandage.

54. The apparatus of any one of the preceding claims, wherein the cover is integrally formed with the receptacle.

55. The apparatus of claim 14, wherein the fluid is deliverable to the receptacle via the first opening of the cover.

56. The apparatus of claim 55, wherein the first opening is adapted for receiving the fluid inlet conduit there through.

57. The apparatus of claim 54 or claim 56, wherein the cover has a second opening via which the fluid is receivable from the receptacle.

58. The apparatus of claim 57, further comprising a first fluid outlet conduit arranged in fluid communication with the receptacle, wherein the second opening is adapted for receiving the first fluid outlet conduit.

59. The apparatus of claim 58, wherein the compartment is further bounded by the first fluid outlet conduit.

60. The apparatus of claim 57, wherein the cover has a third opening via which the fluid is receivable from the compartment substantially bounded by the cover, the receptacle, and the tissue area.

61. The apparatus of claim 60, further comprising a second fluid outlet conduit arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle, and the wound area, wherein the third opening is adapted for receiving the second fluid outlet conduit.

62. The apparatus of any one of claims 55 to 61, further comprising a pressure relief valve in communication with the first opening and/or the receptacle and operable to relieve pressure within the receptacle.

63. The apparatus of any one of claims 55 to 62, further comprising a first fluid outlet conduit arranged in fluid communication with the receptacle and a second fluid outlet conduit arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle and the wound area, wherein at least two of the fluid inlet conduit, the first fluid outlet conduit, and the second fluid outlet conduit are formed as a combined conduit.

64. The apparatus of claim 63, wherein the at least two of the fluid inlet conduit, the first fluid outlet conduit, and the second fluid outlet conduit are formed as a coaxial conduit.

65. The apparatus of claim 63 or claim 64, wherein the combined conduit or the coaxial conduit pass through a single opening in the cover.

66. The apparatus of any one of claims 61 to 64, wherein at least one of the fluid inlet conduit, the first fluid outlet conduit and the second fluid outlet conduit passes into the compartment adjacent an outer edge of the cover.

67. The apparatus of any one of the preceding claims, wherein the cover is salable to the tissue area.

68. The apparatus of claim 67,wherein the cover is hermetically salable to the tissue area.

69. The apparatus of claim 64 or claim 65, wherein the cover is salable to the tissue area by one of an adhesive seal or a suction seal.

70. The apparatus of any one of claims 67 to 69, wherein the tissue area comprises a wound area including a wound and skin adjacent the wound, wherein the cover is salable to the skin adjacent the wound.

71. The apparatus of any one of claims 1 to 69, wherein the tissue area comprises a wound area.

72. The apparatus of any one of the preceding claims, wherein the cover comprises one or more walls that are adapted to allow molecules to pass through via molecular diffusion at only a negligible rate of diffusion.

73. The apparatus of any one of the preceding claims, wherein the compartment substantially bounded by the cover, the receptacle and the tissue area is pressurised during use to form a negative pressure compartment.

74. The apparatus of any one of the preceding claims, comprising a negative pressure source arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle and the tissue area for applying a negative pressure to the compartment.

75. The apparatus of claim 74, wherein the negative pressure source is a pump.

76. The apparatus of any one of claim 73 to claim 75, wherein the pressure in the compartment is altered to be between approximately 50mmHg to 150mmHg or between approximately 80mmHg to 125mmHg or between 90mmHg to 110mmg below atmospheric pressure.

77. The apparatus of any one of the preceding claims, wherein the fluid comprises a therapeutic gas.

78. The apparatus of claim 77, wherein the gas comprises oxygen and/or carbon dioxide.

79. The apparatus of any one of the preceding claims, wherein the apparatus further comprises a fluid source.

80. The apparatus of claim 79, wherein the fluid source comprises a wall source, gas bottle, gas concentrator, or other gas generator.

81. The apparatus of any one of the preceding claims, wherein the receptacle forms a reservoir adapted for storing fluid therein.

82. The apparatus of claim 81, wherein the reservoir is inflatable.

83. The apparatus of claim 81 or claim 82, wherein the reservoir is fillable with the fluid.

84. The apparatus of claim 83, wherein the reservoir is adapted to be filled with fluid during use of the apparatus.

85. The apparatus of claim 83, wherein the reservoir is adapted to be filled with fluid prior to positioning the reservoir at the tissue area.

86. The apparatus of claim 83, wherein the reservoir is pre-filled with fluid during manufacture of the apparatus.

87. The apparatus of any one of claims 81 to 85, wherein the reservoir is configured to provide fluid to the tissue upon disconnection of the reservoir from the fluid source.

88. An apparatus for supplying fluid to a tissue area, the apparatus comprising:

a receptacle positionable at a tissue area, the receptacle comprising one or more walls and being adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow the fluid to pass from the receptacle to the tissue area; and

a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the tissue area;

a first opening in the cover via which fluid is deliverable to the receptacle; a second opening in the cover via which fluid is receivable from the receptacle; and a third opening in the cover via which fluid is receivable from the compartment substantially bounded by the cover, the receptacle and the tissue area.

89. The apparatus of claim 88, further comprising a fluid inlet conduit arranged in fluid communication with the receptacle for delivery of fluid to the receptacle.

90. The apparatus of claim 89, wherein the first opening is adapted for receiving the fluid inlet conduit there through.

91. The apparatus of any one of claims 89 to 90, further comprising a first fluid outlet conduit arranged in fluid communication with the receptacle, wherein the second opening is adapted for receiving the first fluid outlet conduit.

92. The apparatus of any one of claims 89 to 91, further comprising a second fluid outlet conduit arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle, and the tissue area, wherein the third opening is adapted for receiving the second fluid outlet conduit.

93. The apparatus of any one of claims 88 to 92, wherein the compartment substantially bounded by the cover, the receptacle, and the tissue area is further bounded by one or more of the first inlet conduit and the first fluid outlet conduit.

94. The apparatus of any one of claims 89 to 92, further comprising a pressure relief valve in communication with the first opening and/or the receptacle and operable to relieve pressure within the first opening and/or receptacle.

95. The apparatus of claim 92, 93 or 94, wherein at least one of the fluid inlet conduit, the first fluid outlet conduit and the second fluid outlet conduit passes into the compartment adjacent an outer edge of the cover.

96. The apparatus of any one of the preceding claims, wherein the cover is salable to the tissue area.

97. The apparatus of claim 96,wherein the cover is hermetically salable to the tissue area.

98. The apparatus of claim 95 or claim 96, wherein the cover is salable to the tissue area by one of an adhesive seal or a suction seal.

99. The apparatus of any one of claims 96 to claim 98 wherein the tissue area comprises a wound area including a wound and skin adjacent the wound, wherein the cover is salable to the skin adjacent the wound.

100. The apparatus of any one of the preceding claims, wherein the cover comprises one or more walls that are adapted to allow molecules to pass through via molecular diffusion at only a negligible rate of diffusion.

101. The apparatus of any one of claims 88 to 100, wherein the cover is configured to secure the receptacle to the tissue area.

102. The apparatus of any one of claims 88 to 101, wherein the cover is configured to press the receptacle onto or into the tissue area.

103. The apparatus of any one of claims 88 to 102, wherein the cover comprises an absorbent material for absorbing exudate from the wound area.

104. The apparatus of any one of the preceding claims, wherein the cover is integrally formed with the receptacle.

105. The apparatus of any one of claims 88 to 104, wherein the receptacle is inflatable.

106. The apparatus of any one of claims 88 to 105, wherein the receptacle is in the form of a bag.

107. The apparatus of any one of claims, 88 to 106, wherein the receptacle is configured to contact the tissue area.

108. The apparatus of any one of claims 88 to 107, wherein the receptacle is moveable within the compartment substantially bounded by the cover, the receptacle and the tissue area.

109. The apparatus of any one of claims 88 to 108, wherein at least the at least one section of the receptacle is conformable with a surface of the tissue area.

110. The apparatus of any one of claims 88 to 109, wherein the at least one section is adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

111. The apparatus of any one of claims 88 to 110, wherein the at least one section is adapted to allow the fluid to pass from the receptacle to the tissue area by pore flow.

112. The apparatus of any one of claims 88 to 111, wherein the at least one section of the receptacle has an undulating outer surface when at least partially inflated.

113. The apparatus of any one of claims 88 to 112, wherein the at least one section of the receptacle comprises a stretchable material.

114. The apparatus of any one of claims 88 to 113, wherein the receptacle is connected to the cover at a single connection point or at two connection points.

115. The apparatus of claim 89, wherein the fluid inlet conduit passes through or is connected to the first opening.

116. The apparatus of claim 115, wherein the receptacle is connected to the cover via the fluid inlet conduit.

117. The apparatus of any one of claims 89 to 116, further comprising a fastener for securing the receptacle in place at the tissue area.

118. The apparatus of claim 117, wherein the fastener comprises adhesive.

119. The apparatus of any one of claims 89 to 118, wherein the fluid inlet conduit includes a pressure relief valve.

120. The apparatus of any one of claims 89 to 119, wherein the cover comprises one or more walls and wherein the one or more walls are independent of the one or more walls of the receptacle.

121. The apparatus of any one of claims 89 to 119, wherein the receptacle and the cover share a common wall.

122. The apparatus of any one of claims 89 to 121, wherein the receptacle is fillable with the fluid during use of the apparatus.

123. The apparatus of any one of claims 89 to 121, wherein the receptacle is adapted to be filled with fluid prior to positioning the receptacle at the tissue area.

124. The apparatus of any one of claims 89 to 121, wherein the receptacle is pre-filled with the fluid during manufacture of the apparatus.

125. The apparatus of any one of claims 89 to 124, wherein the one or more walls of the receptacle may define one or more through-holes through the receptacle.

126. The apparatus of any one of the preceding claims, including a plurality of the receptacles.

127. The apparatus of any one of claims 88 to 126, further comprising structures associated with the at least one section of the receptacle, the structures being configured to contact the tissue area.

128. The apparatus of claim 127, wherein the structures are configured for encouraging cell growth.

129. The apparatus of claim 127 or 128, wherein the structures are microstructures.

130. The apparatus of claim 129, wherein the microstructures comprise formations which protrude from the one or more walls of the receptacle.

131. The apparatus of claim 129 or claim 130, wherein the microstructures allow molecules within the fluid to diffuse through the at least one section of the receptacle and the microstructures into the tissue area.

132. The apparatus of claim 130 or claim 131, wherein the microstructures protrude from a tissue facing surface of the one or more walls of the receptacle.

133. The apparatus of any one of claims 130 to 132, wherein the formations have one or more of a parabolic, trapezoidal, semi-spherical, spherical, pyramidal, conical, or frustoconical shape.

134. The apparatus of any one of claims 129 to 133, wherein the microstructures have rounded edges.

135. The apparatus of any one of claims 88 to 134, wherein the at least one section of the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

136. The apparatus of any one of claims 88 to 135, wherein the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

137. The apparatus of claim 135 or claim 136, wherein the membrane is adapted to allow the fluid to pass from the receptacle to the tissue area by pore flow.

138. The apparatus of any one of claims 135 to 136, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is substantially pore-free.

139. The apparatus of any one of claims 135 to 136 or claim 138, wherein the membrane comprises substantially no discontinuities or pores that are visible with an optical or electron microscope at a specified resolution.

140. The apparatus of claim 139, wherein the specified resolution is on the order of 1 micrometre.

141. The apparatus of any one of claims 135 to 140, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area comprises at least one of the following: liquid silicone rubber, pre-formed silicone sheet, silicone hydrogel, linear low density polyethylene treated with calcium carbonate, silicone coatings, and high consistency rubber silicone.

142. The apparatus of any one of claims 135 to 141, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is configured to contact the tissue area.

143. The apparatus of any one of claims 136 to 142, wherein the one or more walls of the receptacle, including the at least one section, comprise the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area.

144. The apparatus of any one of claims 88 to 142, wherein the one or more walls of the receptacle, other than the at least one section, comprise a material adapted to allow molecules to pass through via molecular diffusion at only a negligible rate of diffusion.

145. The apparatus of any one of claims 88 to 144, wherein the at least one section is conformable to the surface of the tissue area.

146. The apparatus of any one of claims 88 to 145, wherein the at least one section has a wall thickness of between about 20 micrometres and 150 micrometres, or between about 30 micrometres and 130 micrometres, or between about 35 micrometres and 100 micrometres, or between about 40 micrometres and 80 micrometres or between about 45 micrometres and 55 micrometres.

147. The apparatus of claim 146, wherein the at least one section has a wall thickness of approximately 50 micrometres.

148. The apparatus of any one of claims 136 to 145, wherein the membrane is impermeable to bulk transport of liquid.

149. The apparatus of any one of the preceding claims, wherein the at least one section of the one or more walls of the receptacle are hydrophobic.

150. The apparatus of any one of claims 136 to 149, wherein molecules within a liquid can only pass from one side of the membrane to the other via diffusion.

151. The apparatus of any one of claims 88 to 150, wherein the compartment substantially bounded by the cover, the receptacle and the tissue area is pressurised during use to form a negative pressure compartment.

152. The apparatus of any one of claims 88 to 151, comprising a negative pressure source arranged in fluid communication with the compartment substantially bounded by the cover, the receptacle and the tissue area for applying a negative pressure to the compartment.

153. The apparatus of claim 152, wherein the negative pressure source is a pump.

154. The apparatus of claim 151, wherein the pressure in the compartment is altered to be between approximately 50mmHg to 150mmHg or between approximately 80mmHg to 125mmHg or between 90mmHg to 1OmmHg below atmospheric pressure.

155. The apparatus of any one of claims 88 to 154, wherein the fluid comprises a therapeutic gas.

156. The apparatus of claim 155, wherein the gas comprises oxygen and/or carbon dioxide.

157. The apparatus of any one of claims 88 to 153, wherein the apparatus further comprises a fluid source.

158. The apparatus of claim 157, wherein the fluid source comprises a wall source, gas bottle gas concentrator, or other gas generator.

159. The apparatus of any one claims 88 to 158, wherein the receptacle comprises a tubular receptacle having a fluid inlet and a fluid outlet.

160. The apparatus of any one of claims 88 to 159, wherein the tissue area comprises a wound area.

161. An apparatus for supplying fluid to a tissue area, the apparatus comprising:

a plurality of receptacles positionable at a tissue area, each receptacle comprising one or more walls and being adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow the fluid to pass from the receptacle to the tissue area.

162. The apparatus of claim 25 or claim 126 or claim 161, wherein the one or more walls of each of the plurality of receptacles are independent of the one or more walls of the other receptacles.

163. The apparatus of claim 161 or claim 162, wherein each receptacle of the plurality of receptacles is individually positionable at the tissue area.

164. The apparatus of any one of claims 161 to 163, wherein each receptacle of the plurality of receptacles is associated with a separate fluid supply.

165. The apparatus of any one of claims 161 to 164, wherein the apparatus comprises at least one manifold for providing fluid to each receptacle of the plurality of receptacles.

166. The apparatus of any one of claims 161 to 165, further comprising a plurality of fluid inlet conduits, wherein each receptacle of the plurality of receptacles is in fluid communication with a respective fluid inlet conduit of the plurality of fluid inlet conduits, via which fluid is supplied to the respective receptacle.

167. The apparatus of any one of claims 161 to 166, wherein each of the receptacles is arranged in fluid communication with at least one other of the receptacles.

168. The apparatus of any one of claims 161 to 167, wherein one or more of the receptacles of the plurality of receptacles has a plurality of microstructures formed thereon.

169. The apparatus of any one of claims 162 to 168, further comprising a cover positionable over the plurality of receptacles to form a compartment substantially bounded by the cover, the plurality of receptacles and the tissue area.

170. The apparatus of claim 169 when dependent on claim 166, wherein the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by the plurality of fluid inlet conduits.

171. The apparatus of claim 169 when dependent on claim 166, wherein the plurality of fluid inlet conduits are in fluid communication with the manifold and wherein the manifold has a fluid supply conduit that passes through a single opening in the cover.

172. The apparatus of claim 171, wherein the compartment substantially bounded by the cover, the receptacle and the tissue area is further bounded by the plurality of fluid inlet conduits, the manifold and the fluid supply conduit.

173. The apparatus of claim 169 when dependent upon claim 166, wherein each fluid inlet conduit of the plurality of fluid inlet conduits passes through a respective opening in the cover.

174. The apparatus of claim 169, when dependent on claim 166, wherein each fluid inlet conduit of the plurality of fluid inlet conduits extends around an outer edge of the cover to an associated fluid supply.

175. The apparatus of any one of claims 161 to 174, wherein the at least one section of the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

176. The apparatus of any one of claims 161 to 175, wherein the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

177. The apparatus of any one of claims 175 to 176, wherein the membrane is adapted to allow the fluid to pass from the receptacle to the tissue area by pore flow.

178. The apparatus of any one of claims 175 to 176, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is substantially pore-free.

179. The apparatus of any one of claims 175 to 176 or claim 178, wherein the membrane comprises substantially no discontinuities or pores that are visible with an optical or electron microscope at a specified resolution.

180. The apparatus of claim 179, wherein the specified resolution is on the order of 1 micrometre.

181. The apparatus of any one of claims 175 to 180, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area comprises at least one of the following: liquid silicone rubber, pre-formed silicone sheet, silicone hydrogel, linear low density polyethylene treated with calcium carbonate, silicone coatings, and high consistency rubber silicone.

182. The apparatus of any one of claims 175 to 181, wherein the membrane is impermeable to bulk transport of liquid.

183. The apparatus of any one of claims 175 to 182 wherein molecules within a liquid can only pass from one side of the membrane to the other via diffusion.

184. The apparatus of any one of the preceding claims, wherein the at least one section of the one or more walls of the receptacle are hydrophobic.

185. The apparatus of any one of claims 161 to 184, wherein the fluid comprises a therapeutic gas.

186. The apparatus of claim 185, wherein the gas comprises oxygen and/or carbon dioxide.

187. The apparatus of any one of claims 161 to 186, wherein the tissue area comprises a wound area.

188. An apparatus for supplying fluid to a tissue, the apparatus comprising: a receptacle positionable at a tissue area, the receptacle comprising one or more walls and adapted to receive a fluid, the one or more walls comprising at least one section adapted to allow molecules within the fluid to pass from the receptacle to the tissue area; a fluid inlet in fluid communication with the receptacle; and a pressure relief valve in fluid communication with the fluid inlet and/or the receptacle and operable to relieve pressure within the fluid inlet and/or receptacle.

189. The apparatus of claim 188, wherein the receptacle is inflatable.

190. The apparatus of any one of claims 188 to 189, further comprising a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the tissue area, wherein the pressure relief valve is positioned inside the compartment such that the compartment is further bounded by the pressure relief valve.

191. The apparatus of any one of claims 188 to 189, further comprising a cover positionable over the receptacle to form a compartment substantially bounded by the cover, the receptacle and the wound area, wherein the pressure relief valve is positioned outside of the compartment.

192. The apparatus of any one of claims 188 to 191, wherein the fluid inlet comprises an opening formed in the cover.

193. The apparatus of any one of claims 188 to 192, wherein the at least one section of the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

194. The apparatus of any one of claims 188 to 193, wherein the receptacle comprises a membrane adapted to allow molecules within the fluid to diffuse from the receptacle to the tissue area.

195. The apparatus of claim 193 or claim 194, wherein the membrane is adapted to allow the fluid to pass from the receptacle to the tissue area by pore flow.

196. The apparatus of any one of claims 193 to 194, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area is substantially pore-free.

197. The apparatus of any one of claims 193 to 194 or 196, wherein the membrane comprises substantially no discontinuities or pores that are visible with an optical or electron microscope at a specified resolution.

198. The apparatus of claim 197, wherein the specified resolution is on the order of 1 micrometre.

199. The apparatus of any one of claims 193 to 198, wherein the membrane adapted to allow molecules to diffuse from the receptacle to the tissue area comprises at least one of the following: liquid silicone rubber, pre-formed silicone sheet, silicone hydrogel, linear low density polyethylene treated with calcium carbonate, silicone coatings, and high consistency rubber silicone.

200. The apparatus of any one of claims 193 to 199, wherein the membrane is impermeable to bulk transport of liquid.

201. The apparatus of any one of claims 193 to 199, wherein molecules within a liquid can only pass from one side of the membrane to the other via diffusion.

202. The apparatus of any one of the preceding claims, wherein the at least one section of the one or more walls of the receptacle are hydrophobic.

203. The apparatus of any one of claims 188 to 202, wherein the receptacle has a plurality of microstructures formed thereon.

204. The apparatus of any one of claims 188 to 203, wherein the fluid comprises a therapeutic gas.

205. The apparatus of claim 204, wherein the gas comprises oxygen and/or carbon dioxide.

206. The apparatus of any one of claims 188 to 205, wherein the tissue area comprises a wound area.

207. A kit of parts, comprising an apparatus as claimed in any one of claims 161 to 187 and a dressing.

208. The kit of parts of claim 207, further comprising a fluid source.

209. The kit of parts of claim 207 or claim 208, further comprising an absorbent material.

210. The kit of parts of claim 207 or claim 208, wherein the dressing comprises a compression bandage or an adhesive dressing.

211. A kit of parts, comprising an apparatus as claimed in any one of claims 161 to 187 and a fluid source.

212. The kit of claim 208 or claim 211, wherein the fluid source is a portable fluid source.

213. A kit of parts, comprising an apparatus as claimed in any one of claims I to 87, a negative pressure source and a fluid pump.

214. The kit of parts of claim 213, further comprising a portable fluid source.