SELECTIVELY CONFIGURABLE WOUND DRESSING

Abstract

A wound dressing is selectively configurable for use in a pressure gradient wound therapy system and for use without a pressure gradient wound therapy system. The wound dressing can include a covering layer, an aperture and a microbial barrier. The microbial barrier can be arranged to cover the aperture.

Claims

1. A wound dressing selectively configurable for use in a pressure gradient wound therapy system and for use without a pressure gradient wound therapy system; the wound dressing comprising: a wound contact layer having a first surface for contacting a wound and an opposing second surface; and a covering layer having a first surface facing the wound contact layer and defining a wound dressing cavity and an opposing second surface; the covering layer further comprising an aperture configured to provide fluid communication between the wound dressing cavity and an environment external to the dressing for use of the wound dressing with a pressure gradient wound therapy system; wherein the wound dressing comprises a microbial barrier covering the aperture for use of the wound dressing without a pressure gradient wound therapy system.

2. A wound dressing according to claim 1 wherein the microbial barrier comprises an occlusive material.

3. A wound dressing according to any preceding claim wherein the microbial barrier comprises a releasable layer.

4. A wound dressing according to claim 3 wherein the releasable layer is a flap, the flap comprising a covering portion and a release tab; wherein the covering portion is releasably adhered to the covering layer with a releasable adhesive and the release tab is not adhered to the covering layer.

5. A wound dressing according to claim 4 wherein the releasable adhesive is arranged on the second surface of the covering layer.

6. A wound dressing according to claim 5 wherein the release tab is configured to be pulled by a user to expose the aperture.

7. A wound dressing according to claim 6 wherein the releasable adhesive is configured to adhere to a port once the aperture is exposed.

8. A wound dressing according to claim 5 wherein the covering layer comprises a plurality of perforations defining a perimeter of the aperture, wherein the section of the covering layer within the perforations is a removeable portion is configured to tear away from the remainder of the covering layer and is adhered to the releasable layer.

9. A wound dressing according to any preceding claim wherein when configured for use without the pressure gradient wound therapy system the wound dressing does not comprise a port.

10. A wound dressing according to any preceding claim wherein the aperture is configured to provide fluid communication between the wound dressing cavity and a source of non-atmospheric pressure.

11. A wound dressing according to any preceding claim wherein the microbial barrier is a foil.

12. A wound dressing according to any preceding claim wherein the microbial barrier is a film.

13. A method of configuring a selectively configurable wound dressing; the wound dressing being configurable for use in a pressure gradient wound therapy system and without a pressure gradient wound therapy system; the wound dressing comprising a covering layer and a microbial barrier, the covering layer comprising an aperture to provide fluid communication between a wound dressing cavity and an environment external to the dressing; and the microbial barrier covering the aperture; the method comprising: configuring the wound dressing for use with a pressure gradient wound therapy system by applying a source of non-atmospheric pressure to the aperture.

14. A method of configuring a selectively configurable wound dressing according to claim 13 wherein the method further comprises breaking or removal of the microbial barrier.

15. A method of configuring a selectively configurable wound dressing according to claim 13 or 14, wherein the covering layer comprises perforations defining a perimeter of the aperture and the method comprising removing the section of the covering layer within the perforations.

16. A method of configuring a selectively configurable wound dressing according to claim 15, wherein the wound dressing comprises a releasable layer and the method comprising removing the releasable layer to remove the section of the covering layer within the perforations.

17. A method of configuring a selectively configurable wound dressing according to any of claims 13 to 16 wherein the method further comprises applying a port to surround the aperture.

18. A method of configuring a selectively configurable wound dressing according to any of claims 13 to 17 wherein the wound dressing is configured in-situ.

19. A method of configuring a selectively configurable wound dressing according to any of claims 13 to 18 wherein the wound dressing is a wound dressing according to any of claims 1 to 12.

20. A kit of parts including a selectively configurable wound dressing, the wound dressing being configurable for use in a pressure gradient wound therapy system and without a pressure gradient wound therapy system; the kit further comprising at least one of: a. packaging indicating that the wound dressing is selectively configurable for use in a pressure gradient wound therapy system and without a pressure gradient wound therapy system; b. instructions instructing a user as to how to configure the wound dressing for use in a pressure gradient wound therapy system and for use without a pressure gradient wound therapy system; c. a source of non-atmospheric pressure; d. a port for connection to the covering layer of the wound dressing to connect the wound dressing to a source of non-atmospheric pressure; or e. tubing for connection between a wound dressing and a source of non-atmospheric pressure; wherein the wound dressing comprises a wound contact layer and a covering layer, the covering layer having a first surface facing the wound contact layer and defining a wound dressing cavity, and a second surface; wherein the covering layer comprises an aperture, the aperture configured to provide fluid communication between the wound dressing cavity and a source of non-atmospheric pressure; wherein the wound dressing comprises a microbial barrier covering the aperture for use of the wound dressing without a pressure gradient wound therapy system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0077] In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0078] FIG. 1 is a schematic representation of an embodiment of a wound dressing configured for use without a wound therapy apparatus;

[0079] FIG. 2 is a schematic representation of the wound dressing of FIG. 1 configured for use with a wound therapy apparatus;

[0080] FIG. 3 is a schematic representation of another embodiment of a wound dressing configured for use without a wound therapy apparatus;

[0081] FIG. 4 is a schematic representation of another embodiment of a wound dressing configured for use without a wound therapy apparatus;

[0082] FIG. 5 is a schematic representation of the wound dressing of FIG. 4 configured for use with a wound therapy apparatus;

[0083] FIG. 6 is a schematic view of the unconnected port components of the wound dressing of FIG. 5;

[0084] FIG. 7 is a schematic view of the connected port components of the wound dressing of FIG. 5;

[0085] FIG. 8 is an exploded view of a wound dressing of any of FIGS. 1-5;

[0086] FIG. 9 is a cross sectional view through the wound dressing of FIG. 8;

[0087] FIG. 10 is a schematic representation of a wound exudate management system according to certain embodiments; and

[0088] FIG. 11 is a schematic representation of a kit of parts.

[0089] Embodiments disclosed herein relate to apparatus and methods of treating a wound both with and without reduced or positive pressure (typically negative pressure). Some embodiments including pump and wound dressing component. The wound dressings discussed are “one-piece” dressings incorporating both a covering layer and an absorbent body.

[0090] As disclosed herein the present invention may comprise a wound dressing; or a kit comprising the wound dressing and other apparatus for providing pressure gradient wound therapy to a wound.

[0091] As used herein the expression “wound” may include an injury to living tissue may be caused by a cut, blow, or other impact, typically one in which the skin is cut or broken. A wound may be a chronic or acute injury. Acute wounds occur as a result of surgery or trauma. They move through the stages of healing within a predicted timeframe. Chronic wounds typically begin as acute wounds. The acute wound can become a chronic wound when it does not follow the healing stages resulting in a lengthened recovery. It is believed that the transition from acute to chronic wound can be due to a patient being immuno compromised.

[0092] Chronic wounds may include for example: venous ulcers (such as those that occur in the legs), which account for the majority of chronic wounds and mostly affect the elderly, diabetic ulcers (for example, foot or ankle ulcers), peripheral arterial disease, pressure ulcers, or epidermolysis bullosa (EB).

[0093] Examples of other wounds include, but are not limited to, abdominal wounds or other large or incisional wounds (either as a result of surgery, trauma, stemiotomies, fasciotomies, or other conditions), dehisced wounds, acute wounds, chronic wounds, subacute and dehisced wounds, traumatic wounds (such as from orthopaedic trauma), flaps and skin grafts, lacerations, abrasions, contusions, burns, diabetic ulcers, pressure ulcers, stoma, surgical wounds, trauma and venous ulcers, broken bones or the like.

[0094] Wounds may also include a deep tissue injury. Deep tissue injury is a term proposed by the National Pressure Ulcer Advisory Panel (NPUAP) to describe a unique form of pressure ulcers. These ulcers have been described by clinicians for many years with terms such as purple pressure ulcers, ulcers that are likely to deteriorate and bruises on bony prominences.

[0095] The technology disclosed can be used on an acute or chronic wound.

[0096] Wounds are believed to be more susceptible to infection under the following circumstances. If the wounds are chronic wounds, or if an object which caused the wound was dirty or contained bacteria, or from a bite, or contains remnant or a whole object that caused the wound, or a wound that is large or deep, or jagged edges to the wound, or elderly, or chronic because by their nature a wound site is open; and/or if the patient has: diabetes type 1 or type 2, is elderly, or has a compromised immune system.

[0097] Pressure gradient wound therapy may also be useful for treating second- and third-degree burns, as well as being useful for laparotomy surgery i.e., a large incision through an abdominal wall to gain access into the abdominal cavity.

[0098] FIGS. 1 and 2 illustrate an embodiment of a wound dressing 10 in accordance with the invention in two different configurations.

[0099] In general, the invention relates to a wound dressing 10, which is selectively configurable for use without a pressure gradient wound therapy system or for use with a pressure gradient wound therapy system, e.g. negative pressure wound therapy.

[0100] As shown in FIG. 1, the wound dressing 10 includes an aperture 12 in a covering layer 13 of the dressing 10. The covering layer 13 has a raised central region 14, where it overlies a dressing body, which can include a pressure dispersion layer; an absorbent/superabsorbent layer/layers; and a wound-contact layer. The dressing 10 also has a border region 15, where it overlies an adhesive layer. A removable release layer (not shown) is provided on the underside.

[0101] The aperture 12 and covering layer 13 proximate to the aperture 12 are covered by a flap 16. The flap 16 of this embodiment is formed from a plastics film, such as polyethylene and releasably adhered to the covering layer 13 surrounding the aperture 12. In this particular embodiment, the adhesive that releasably adheres to the flap 16 is applied to, and adheres more strongly to the outside surface of the covering layer 13. The flap also has a tapered release tab 11 from one edge of the flap 16, the release tab 11 is not adhered to the covering layer.

[0102] As illustrated in FIG. 1, the wound dressing is configured for use without a pressure gradient wound therapy system. To use the wound dressing 10 without a pressure gradient wound therapy system, the release layer (not shown) on the underside is simply removed and the dressing applied in the same way as an ordinary wound dressing. It will be noted that when the flap 16 covers the aperture 12, it forms a microbial barrier, and as such, the entire raised central region 14 of the covering layer 13 is closed, so that the wound (within the region defined by the adhesive border) is in a sealed environment restricting/preventing bacteria/microbes entering the wound and causing infection.

[0103] FIG. 2 shows the wound dressing 10 of FIG. 1 configured for use with a pressure gradient wound therapy system. Here, a user has peeled back the flap 16, by pulling on the release tab 11, to expose the aperture 16 in the wound dressing 10 (so that the central region 14 is interrupted and no longer closed). With the wound dressing 10 now configured for use with a pressure gradient therapy system, a source of non-atmospheric, e.g. negative, pressure can be connected to the aperture 12 to aid the wound-healing process. Those skilled in the art will appreciate that the steps to configure the wound dressing 10 for use with a pressure gradient wound therapy system can be undertaken either prior to or after the wound dressing 10 has been applied to the wound (i.e. the wound dressing can be configured for use with a pressure gradient wound therapy system in-situ).

[0104] For example, a port (not shown in FIG. 1 or 2) can be adhered to the wound dressing 10, such that a conduit through the port is aligned with the aperture 16; the port can be connected via tubing (also not shown in FIGS. 1 and 2) to a pump (also not shown in FIGS. 1 and 2) producing negative pressure. Optionally, the releasable adhesive which held the flap 16 may also be used to adhere the port to the covering layer 13.

[0105] Optionally in this embodiment the space within the aperture 12 may not be empty when the wound dressing is configured for use without a pressure gradient wound therapy system. That is to say, the covering layer 13 may be perforated, with a plurality of perforations, arranged to define a perimeter of an aperture, but without the “chad” defined by the perforations removed. As such, when configuring the wound dressing for use with a pressure gradient wound therapy system, when the user peels back the flap 16 by pulling on the release tab 11, the chad, being adhered to the flap 16 may be removed from the aperture with the flap, emptying the space defined by the aperture. However, unlike as outlined above the space within the aperture 12 would not be exposed, before the chad is removed.

[0106] FIG. 3 illustrates a further embodiment of a wound dressing 20 in accordance with the invention.

[0107] As shown in FIG. 3, the wound dressing 20 includes an aperture 22 in a covering layer 23 of the dressing 20. The covering layer 23 has a raised central region 24, where it overlies a dressing body, which can include a pressure dispersion layer; an absorbent/superabsorbent layer/layers; and a wound-contact layer. The dressing 20 also has a border region 25, where it overlies an adhesive layer. A removable release layer (not shown) is provided on the underside.

[0108] The aperture 22 is covered with a semipermeable membrane 21, in this embodiment the semipermeable membrane 21 is provided on the exterior surface of the covering layer, however it will be evident to those skilled in the art that it equally could be applied to the interior surface of the covering layer. The semipermeable membrane of this embodiment is a polyurethane film of 25-30 microns in thickness, which is permeable to gas and moisture vapour, but impermeable to liquid and microbes. It may, for example have a moisture vapour transmission rate of 4500 g/m.sup.2/24 hr

[0109] Those skilled in the art will appreciate that a variety of materials can be selected for the semi-permeable membrane; dependent on the exact properties required, for example the gas and moisture vapour permeability.

[0110] To use the wound dressing 20 without a pressure gradient wound therapy system, the release layer on the underside is simply removed and the dressing 20 applied in the same way as an ordinary wound dressing. It will be noted semipermeable membrane 21 functions here as a microbial barrier, and as such, again the entire raised region formed by the covering layer 23 and the semipermeable membrane 21 is closed so bacteria cannot enter the cavity within the wound dressing 20 bounded by the border region 25.

[0111] To use the wound dressing 20 with a pressure gradient wound therapy system a source of non-atmospheric, e.g. negative, pressure can be connected to the aperture 22 to aid the wound-healing process.

[0112] For example, a port (not shown in FIG. 3) can be adhered to the wound dressing 20, such that a conduit through the port is aligned with the aperture 26; the port can be connected via tubing (also not shown in FIG. 3) to a pump (also not shown in FIG. 3) producing negative pressure. If the negative pressure wound therapy is to be “canister-less”, the pump will produce a negative pressure beneath the dressing by withdrawing gas through the semi-permeable membrane 21. To use the wound dressing 20 with a system including a cannister, the semi-permeable membrane 21 can be removed (or broken) to allow fluid to be withdrawn through the aperture 22.

[0113] Those skilled in the art will appreciate that the steps to configure the wound dressing 20 for use with a pressure gradient wound therapy system can be undertaken either prior to or after the wound dressing 20 has been applied to the wound (i.e. the wound dressing can be configured for use with a pressure gradient wound therapy system in-situ).

[0114] FIGS. 4 to 7 illustrate a further embodiment of a wound dressing 30 in accordance with the invention.

[0115] Referring to FIG. 4, the wound dressing 30 includes an aperture (not shown) in a covering layer 33 of the dressing 30. The covering layer 33 has a raised central region 34, where it overlies a dressing body, which can include a pressure dispersion layer; an absorbent/superabsorbent layer/layers; and a wound-contact layer. The dressing 30 also has a border region 35, where it overlies an adhesive layer. A removable release layer (not shown) is provided on the underside.

[0116] In this embodiment, the aperture is covered by a filter layer 32, which may, for example be a PTFE membrane filter, available from Whatman plc® (alternative embodiments use a slimline cartridge or PTFE filter from Cole Parmer or a Gore-Tex® PTFE filter from W. L. Gore & Associates. As with the semi-permeable membrane of the previous exemplary embodiment, the filter 32 may be arranged on either an outer or inner surface of the covering layer 33, but in this embodiment the filter layer 32 is arranged on the underside of the connector base plate 31 which is disposed around the aperture, on the outer surface of the covering layer 33. A hole 36 in the centre of the base plate is aligned with the aperture in the covering layer 33.

[0117] FIG. 6 shows the connector base plate 31 and a second port component 40 in an unconnected configuration. The connector base plate 31 is an annular, low profile plate formed, for example, from flexible thermoplastics. The connector base plate has a lower surface (not shown) with the filter layer 32 thereon, which is adhered to the wound dressing 30. Opposite the lower surface is an upper surface 37, the upper surface comprises a means for connection to a second port component 40, in this case three projections 38 arranged on an inner edge of the upper surface 37, the three projections 38 projecting perpendicular to the upper surface 37. The projections 38 form a first part of a cantilever snap fitting between the connector base plate 31 and the second port component 40.

[0118] In this embodiment, the second port component 40 comprises a hemispherical body 41 and a tube connecting portion 42 projecting from the edge of the hemispherical body 41. A conduit is provided within the second port component 40 extending between a tube port 43 on the tube connecting portion 42 and a hole in the lower face of the second port component (not shown). Within the hole of the lower face a second part of the cantilever snap fitting is provided in the form of a recess configured to receive the projections of the first part of the cantilever snap fitting.

[0119] As illustrated in FIG. 4, to use the wound dressing 30 without a pressure gradient wound therapy system, the release layer on the underside is simply removed and the dressing 30 applied in the same way as an ordinary wound dressing. Again, it will be noted filter layer 32 functions here as a microbial barrier, and as such, again the entire raised region formed by the covering layer 33 and the filter membrane 32 is closed so bacteria cannot enter the cavity within the wound dressing 30 bounded by the border region 35.

[0120] FIG. 5 shows the wound dressing 30 configured for use with a pressure gradient wound therapy system. Here, a user has connected the second port component 40 to the port base plate 31 by means for the snap fitting forming a combined port 50 (that is, the combined port comprises the port base plate 31 and the second port component 40 as shown in FIG. 7). The combined port 50 is configured to connect to a source of non-atmospheric, e.g. negative, pressure which in turn allows the source of non-atmospheric pressure to be connected to the aperture to aid the wound-healing process.

[0121] The combined port 50 can be connected via tubing (not shown in FIG. 5) to a pump (also not shown in FIG. 5) producing negative pressure. If the negative pressure wound therapy is to be “canister-less”, the pump will produce a negative pressure beneath the dressing by withdrawing gas through the filter membrane 32. To use the wound dressing 30 with a system including a cannister, the filter membrane 32 can be broken (e.g. cut) or removed to allow fluid to be withdrawn through the aperture.

[0122] Those skilled in the art will appreciate that the steps to configure the wound dressing 30 for use with a pressure gradient wound therapy system can be undertaken either prior to or after the wound dressing 30 has been applied to the wound (i.e. the wound dressing can be configured for use with a pressure gradient wound therapy system in-situ).

[0123] With additional reference to FIGS. 8 and 9, illustrated therein is an exemplary layer composition of the wound dressings 10, 20, 30 of the above embodiments.

[0124] The illustrated wound dressing 300 generally includes a covering layer 310 and an adhesive layer 320 for adhering the wound dressing 300 adjacent the wound. In certain embodiments, the wound dressing 300 further comprises a wound contact layer 330 for contacting the wound, a pressure dispersion layer 340, a plurality of absorbent material layers 350 disposed between the wound contact layer 330 and the pressure dispersion layer 340.

[0125] The covering layer 310 has a first surface 311 and a second surface 312, and the first surface 311 is adjacent, and in contact with, the pressure dispersion layer 340 and the adhesive layer 320. The covering layer 310 defines a cavity in which the pressure dispersion layer 340 is arranged. In certain embodiments, the covering layer 310 is formed of a polyurethane film. The covering layer 310 comprises an aperture 314 is covered by a microbial barrier according to any of the previous embodiments.

[0126] The adhesive layer 320 generally defines a border about an opening 322 for receiving the wound. In certain embodiments, the adhesive layer 320 comprises a silicone adhesive. In certain embodiments, the adhesive layer 320 may be perforated.

[0127] The wound contact layer 330 overlaps the border defined by the adhesive layer 320, and is configured to contact the wound via the opening 322. In certain embodiments, the wound contact layer 330 may comprise Medicel™. In certain embodiments, the wound contact layer 330 comprises carboxymethylated cellulose fibers. In certain embodiments, the wound contact layer 330 may comprise HYDROFIBER®. In certain embodiments, the wound contact layer 330 may be reinforced, for example via nylon stitching. Thus, the wound contact layer 330 may comprise reinforcing nylon stitching 332.

[0128] The pressure dispersion layer 340 is adjacent and in contact with the first surface 311 of the cover layer 310. In certain embodiments, the pressure dispersion layer 340 may be provided as a polyester foam layer. In certain embodiments, the pressure dispersion layer 340 comprises reticulated foam.

[0129] The absorbent material layers 350 are positioned between the wound contact layer 330 and the pressure dispersion layer 340. The wound dressing 300 may, for example, comprise eight absorbent material layers 350. In certain embodiments, one or more of the absorbent material layers 350 may comprise carboxymethylated cellulose fibers. In certain embodiments, one or more of the absorbent material layers 350 may comprise Medicel™. In certain embodiments, one or more of the absorbent material layers 350 may comprise HYDROFIBER®. In certain embodiments, one or more of the absorbent material layers 350 further comprises fenestrations 352.

[0130] In certain embodiments, as shown in FIG. 9, the wound dressing 300 may include an additional layer 370 between the pressure dispersion layer 330 and the uppermost absorbent layer 350. The additional layer 370 may, for example, be formed of thermoplastic. In certain embodiments, the additional layer 370 may be provided as a thermoplastic spun lace layer. In certain embodiments, the wound dressing 300 may further comprise a nonwoven spun lace layer 372 connected to the wound contact layer 330. In certain embodiments, an envelope structure 374 is formed by joining peripheral portions 373 of the thermoplastic spun lace layer 370 and the nonwoven spun lace layer 372 such that the plurality of absorbent material layers 350 are disposed substantially within an interior cavity 375 of the envelope structure 374, for example as illustrated in FIG. 5. In certain embodiments, the absorbent material layers 350 are disposed within the interior cavity 375 of the envelope structure 374.

[0131] In certain embodiments, the wound dressing 300 may include a further layer 380 positioned between the wound contact layer 330 and the lowermost absorbent layer 350. The further layer 380 may, for example, be a polyester/viscose layer.

[0132] As is well known, and therefore not shown, the wound dressing 300 may be provided with a removable release layer on the underside, covering the adhesive layer 320 and the underside of the wound contact layer 330; and it may be individually packaged within a sterile package.

[0133] With additional reference to FIG. 10, illustrated therein is a pressure gradient wound therapy system 400 according to certain embodiments. The pressure gradient wound therapy system 400 comprises a pump 410 for generating negative pressure, a wound dressing 420 (which may be any of the wound dressings 10, 20, 30, 300 described above) for covering and protecting a wound, an inline filter 430, a first pressure tube 440 having a first interior lumen 442, a second pressure tube 450 having a second interior lumen 452, and a flexible connector 460. The first pressure tube 440 is disposed between the pump 410 and the inline filter 430. The second pressure tube 450 is disposed between the inline filter 430 and the flexible connector 460. The flexible connector 460 is disposed between the second pressure tube 450 and the wound dressing 420 such that the pump 410 and the wound dressing 420 are in fluid communication via the interior lumens 442, 452.

[0134] The wound dressings 10, 20, 30, 300, 420 may be provided in kits. As illustrated schematically in FIG. 11, the kits can comprise one or preferably more than one of the selectively configurable wound dressings 10, 20, 30, 300, 420 and at least one of the following items, all of which are included in this exemplary kit:

[0135] (a) packaging 500 indicating that the wound dressing is selectively configurable for use in a pressure gradient wound therapy system and without a pressure gradient wound therapy system. In this example the packaging is a cardboard box, printed with instructions for use.

[0136] (b) instructions instructing a user as to how to configure the wound dressing for use in a pressure gradient wound therapy system and for use without a pressure gradient wound therapy system. In this example, the instructions are printed on a leaflet 502 included in the box.

[0137] (c) a source of non-atmospheric pressure. In this embodiment, the source of non-atmospheric pressure is the pump 410.

[0138] (d) a port for connection to the covering layer of the wound dressing to connect the wound dressing to a source of non-atmospheric pressure. In this embodiment the port is the port 50 described above.

[0139] (e) tubing for connection between a wound dressing and a source of non-atmospheric pressure. In this embodiment tubing 440 described above is included.

[0140] For use where it is envisioned that a wound will initially require treatment with a pressure gradient wound therapy system, the kit may comprise one or more, preferably a plurality of, dressings 10/20/30/300/420 and one or more of items c, d and e, for example all of items c, d, and e, and optionally items a and/or b as well. As such, the user can be provided with all the equipment required to use the wound dressings 10/20/30/300/420 with a pressure gradient wound therapy system.

[0141] In order to use such a kit, the user (e.g. a patient or HCP) can remove the flap 16 to expose the aperture; if using the dressings 10 of the first embodiment, in which the microbial layer is occlusive, attach a port 50 to the dressing, around the aperture, (or complete the port 50, if using the dressings 30 of the third embodiment); attach one end of the tubing 440 to the port 50 and the other to the pump 410 and run the pump 440 to provide non-atmospheric (e.g. negative) pressure to the wound.

[0142] Then, if/when the pressure gradient therapy is no longer necessary, the user can use up any remaining wound dressings 10/20/30/300/420 without the pressure gradient wound therapy system, by applying them to the wound without the elements of the pressure gradient wound therapy system and if using the dressings 10 of the first embodiment, without removing the microbial barrier, so as to maintain a sealed environment around the wound.

[0143] On the other hand, for use where it is envisioned that a wound does not require treatment with a pressure gradient wound therapy system (and most preferably where it is envisioned that a wound does not require treatment with a pressure gradient wound therapy system, but it is considered that there is a risk that the wound will not heal well without a pressure gradient so in future, pressure gradient wound therapy might be useful), the kit may comprise one, or more preferably a plurality of selectively configurable dressings 10/20/30/300/420 and one or both of items a and b. As such, the user has instructions on how to use the dressings without a pressure gradient wound therapy system and can simply apply a dressing 10/20/30/300/420 to the wound in the configuration for use without a pressure gradient wound therapy system. That is, remove the release layer on the underside and apply the wound dressing to the wound, so that the cover layer and microbial barrier form a closed cavity within the adhesive border, and the is wound sealed against bacteria/microbes.

[0144] Then, should it be determined that the wound would benefit from pressure gradient therapy (e.g. negative pressure), the user can follow the instructions from the packaging/instructions to configure the wound dressing 10/20/30 in-situ, that is, where applicable break the microbial barrier (e.g. remove the flap 16), then apply a port or second port component 40 and apply a source of non-atmospheric pressure as outlined above, without having first to remove the dressing 10/20/30/420 (which can present an opportunity for infection).

[0145] Conditional language, such as “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements, and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, and/or steps are included or are to be performed in any particular embodiment.

[0146] Each of the documents referred to above is incorporated herein by reference. Except in Examples, or where otherwise explicitly indicated, all numerical quantities in this description specifying amounts of materials, device dimension, and the like, are to be understood as modified by the word “about.”

[0147] Unless otherwise indicated, each chemical or composition referred to herein should be interpreted as being a commercial grade material which may contain the isomers, by-products, derivatives, and other such materials which are normally understood to be present in the commercial grade.

[0148] The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.