WOUND DRESSING WITH INFLATABLE STRUCTURES

Abstract

Disclosed is a contact layer for a negative pressure wound treatment system, in which the contact layer includes as inflatable channel with an opening for inflation or deflation of a fluid. The contact layer is flexible to be kept close to the intestines and to be possible to wrinkle or fold it in order to fit into the wound. To keep it in the desired position once this is achieved since the contact layer is thin and lacks rigidity and stability and may thus easily be dislocated, the contact layer allows the inflatable channel to be in an uninflated, or slightly inflated, state from the start to be able to easily wrinkle and fold the contact layer first and thereafter, during or after placing the contact layer in position, inflating the channel to increase the rigidity and stability to help to keep the contact layer in its desired position.

Claims

1-16 (canceled)

17. A contact layer (16) for a negative pressure wound treatment system (10) in which said contact layer (16) is adapted to be located between a wound floor (12) and the skin, said contact layer (16) comprising at least one inflatable channel (102, 102a, 102b, 102c, 102d, 102e) which is provided with an opening (104) for inflation or deflation of fluid, wherein said contact layer (16) is liquid permeable.

18. The contact layer (16) according to claim 17, wherein the contact layer comprises at least four inflatable channels.

19. The contact layer (16) according to claim 18, wherein at least some of said inflatable channels (102, 102a, 102b, 102c, 102d, 102e) are designed as oblong channels stretching from the centre portion (108) of the contact layer (16) towards the edges (40) of the contact layer (16).

20. The contact layer (16) according to claim 18, wherein at least some of said inflatable channels (102, 102a, 102b, 102c, 102d, 102e) are designed as circular, oval or asymmetrical channels being circumferentially located around the centre portion (108) of the contact layer (16).

21. The contact layer (16) according to claim 18, wherein all channels (102, 102a, 102b, 102c, 102d, 102e) are connected by communicating conduits and all channels may be (102, 102a, 102b, 102c, 102d, 102e) inflated by introducing fluid through one single opening (104).

22. The contact layer (16) according to claim 18, wherein said channels (102, 102a, 102b, 102c, 102d, 102e ) form groups of channels (102a, 102b, 102c, 102d, 102e) such that the channels in each group are connected by communicating conduits and each group of channels may be separately inflated.

23. The contact layer (16) according to claim 22, wherein a first group of channels (102b) is formed on a first half portion of the contact layer and a second group of channels (102c) is formed on a second half portion, each group of channels on each half portion thus being separately inflated.

24. The contact layer (16) according to claim 17 wherein said contact layer (16) comprising one single inflatable channel (102, 102a, 102b, 102c, 102d, 102e).

25. The contact layer (16) according to claim 17, wherein said contact layer (16) is adapted for use with abdominal wounds and form part of a negative pressure therapy system.

26. The contact layer (16) according to claim 17, wherein said contact layer (16) comprises a top sheet (30) and a bottom sheet (32) and a plurality of inflatable channels (28) located there between.

27. The contact layer (16) according to claim 17, wherein the contact layer comprises sealed chambers (28).

28. A negative pressure abdominal wound treatment system kit, said kit comprising a contact layer (16) according to claim 17, said kit further comprising a wound filler (18) and a wound cover membrane (20), said contact layer (16) being adapted to be applied to a wound floor (12) of said abdominal wound.

29. The contact layer according to claim 19, wherein at least some of said inflatable channels are designed as circular, oval or asymmetrical channels being circumferentially located around the centre portion of the contact layer.

30. The contact layer according to claim 19, wherein all channels are connected by communicating conduits and all channels may be inflated by introducing fluid through one single opening.

31. The contact layer according to claim 20, wherein all channels are connected by communicating conduits and all channels may be inflated by introducing fluid through one single opening.

32. The contact layer according to claim 19, wherein said channels form groups of channels such that the channels in each group are connected by communicating conduits and each group of channels may be separately inflated.

33. The contact layer according to claim 20, wherein said channels form groups of channels such that the channels in each group are connected by communicating conduits and each group of channels may be separately inflated.

34. The contact layer according to claim 18, wherein said contact layer is adapted for use with abdominal wounds and form part of a negative pressure therapy system.

35. The contact layer according to claim 19, wherein said contact layer is adapted for use with abdominal wounds and form part of a negative pressure therapy system.

36. The contact layer according to claim 20, wherein said contact layer is adapted for use with abdominal wounds and form part of a negative pressure therapy system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be explained below by means of non-limiting examples with reference to the accompanying drawings, in which:

[0034] FIG. 1 shows a cross sectional view of a negative pressure wound therapy system comprising a contact layer;

[0035] FIG. 2 shows an isometric view of a contact layer comprising inflatable channels;

[0036] FIG. 3 shows different designs of inflatable channels in a contact layer;

[0037] FIG. 4 shows an isometric view of a contact layer comprising inflatable channels and closed chambers;

[0038] FIG. 5 shows a design of inflatable channels and closed chambers in a contact layer; and

[0039] FIG. 6 shows a contact layer provided with slits.

DETAILED DESCRIPTION OF THE DRAWINGS

[0040] The invention will, in the following, be exemplified by embodiments. It is to be understood, however, that the embodiments are included in order to explain principles of the invention and not to limit the scope of the invention defined by the appended claims.

[0041] FIG. 1 illustrates a negative pressure wound therapy system 10. In FIG. 1, the system 10 is exemplified as a negative pressure wound therapy system for use in the abdomen. As such, the system 10 is adapted for use with abdominal wounds and illustrates the wound floor 12 as well as an abdominal wall 14 of the abdominal wound/open abdomen. The intestines in the bottom of the abdominal cavity can be regarded as the wound floor 12.

[0042] The negative pressure wound therapy system 10 comprises an organ contact layer 16 at least a portion of which is adapted to be located between the wound floor 12 and the abdominal wall 14. Furthermore, the system 10 comprises a wound filler 18 adapted to provide fluid transport between the organ contact layer 16 and a negative pressure source 21. Purely by way of example, the wound filler 18 may comprise a foam material, for instance an open-celled foam material. As a non-limiting example, the wound filler 18 may comprise a flexible open-celled foam material, such as a sponge material. Examples of suitable foam materials include, without limitation, materials comprising polyurethane, polyester, polyether or polyvinyl alcohol or combinations thereof. As a non-limiting example, the foam may be a hydrophobic polymer foam. As another non-limiting example, the wound filler 18 may comprise gauze.

[0043] Moreover, although purely by way of example, the negative pressure source 21 may comprise a negative pressure pump which may be referred to as a vacuum pump. Purely by way of example, the negative pressure source 21 may be adapted to provide a negative pressure, the absolute value of which is greater than or equal to a threshold value. Generally, the threshold value in such embodiments is at least 20 mmHg. In some embodiments, the negative pressure source 21 is adapted to provide negative pressure at one fixed threshold value.

[0044] The negative pressure wound therapy system 10 further comprises a wound cover membrane 20. The wound cover membrane is generally adapted to be attached to the skin surrounding the wound. Purely by way of example, the wound cover membrane 20 may comprise a wound cover film. The wound cover membrane 20 may preferably be attached to the skin surrounding the abdominal wound, for instance by means of an adhesive. Examples of adhesives that may be used include, but are not limited to, acrylic adhesives and/or silicone gel adhesives. In some embodiments, the adhesive or adhesives is/are already incorporated as part of the wound cover film. In some embodiments, the adhesive or adhesives is/are applied to the wound cover member during use. Purely by way of example, the adhesive sold under the trademark Mepiseal by Molnlycke Healthcare AB may be used for attaching the wound cover member to the skin surrounding the wound membrane during use.

[0045] FIG. 1 further illustrates that the negative pressure wound therapy system 10 comprises a fluid communication assembly 22 adapted to provide a fluid communication between the negative pressure source 21 and the wound cover membrane 20. The fluid communication assembly 22 may for instance comprise a suction device 24 and a conduit assembly 26 comprising one or more conduits.

[0046] Arrows in FIG. 1 indicate how liquid may travel from the abdominal wound towards the negative pressure source 21 via the organ contact layer 16, the wound filler 18 and the fluid communication assembly 22, respectively.

[0047] The negative pressure wound therapy system 10 described in FIG. 1 thus discloses one of many examples of a negative pressure wound dressing in which the organ contact layer 16, which is to be described in more detail below, may be applied.

[0048] FIG. 2 illustrates a portion of an organ contact layer 16 according to an embodiment of the present invention. The organ contact layer 16 comprises one or a plurality of inflatable channels 102 which have been inflated with a fluid. The purpose of these channels is to provide rigidity and stability to the organ contact layer when the channels 102 are filled with a fluid. The rigidity and stabilizing effect depends among other things on the level or pressure of the filling fluid. By determining the level of rigidity and stability of the organ contact layer it also makes it possible to shape it accurately and position the organ contact layer optimally.

[0049] The organ contact layer 16 has a planar extension in a first plane defined by the X- and Y-axis. In this case is the organ contact layer exemplified by a thin sheet 100. The thin sheet 100 is provided with a plurality of inflatable channels 102 (only one channel disclosed in the portion shown in FIG. 2). The channels 102 are elongated and extend in its length direction on the surface of the thin sheet 100 in the first plane . As is obvious from FIG. 2, the channel 102 also has a height such that it protrudes in a direction V perpendicular to the plane . The sheet 100 in FIG. 2 is shown when the channel 102 is inflated with a fluid. When the channel 102 is not inflated, the channel is essentially flat and levelled with the thin sheet 100. In this case it is shown that the base of the channel is essentially levelled with the thin sheet 100 and protrudes upwards, in the positive V-direction. However, the channel 102 may also be designed such that its base is levelled with the thin sheet 100 and protrudes downwards, in the negative V-direction. The channels could also be designed such that the very same channel protrudes in both the negative and positive V-direction, i.e. a channel is protruding from the plane on both the upper and lower side of the sheet 100. In a sheet 100 comprising a multitude of channels 102 may these channels be designed such that all of them are designed to protrude upwards, downwards or in both directions. Alternatively, the sheet 100 may comprise channels 102 protruding differently in the V-direction, e.g. some protruding upwards and others downwards.

[0050] Each one of the channels 102 is provided with at least one opening 104 in order to be inflated. The openings 104 may be connected via linking conduits 106 to a source (not shown) for filling and inflating of the channels 102. As a source for filling the channels 102, linking conduits 106 or chambers 110 may be used (purely as an example) a syringe filled with fluid. The linking conduit for filling (which may have a diameter/width/height that is smaller, equal to or larger than the channels) may be directly connected to the channels or to a common chamber or several connected channels. For example, all or a group of channels 102 may have their linking conduits 106 connected to a common chamber or some kind of manifold such that each one of the channels 102 is directly connected to the common chamber. This chamber is thus adapted to be connected to a fluid source in order to be filled with a fluid and delivering the fluid to the respective channels 102 via their linking conduits 106 or by being directly in contact with the opening 104 of the channels. Alternatively, all or some of the channels 102 may be connected in series such that the filling fluid will pass through one or more channels 102 in order to fill up further channels, which shall be inflated from the source. In this figure, i.e. FIG. 2, the channel 102 is shown as a channel having a single inlet opening 104 connected to a linking conduit 106. In those cases the channels will have a through flow in order to fill up further channels, these channels will obviously have two or more openings having at least one linking conduit 106 connected to another channel 102. The openings 104 and/or the linking conduits 106 may be provided with a one-way valve arrangement such that once a channel 102 is filled it will automatically stay filled until the one way valve is punctuated or in some way disabled. In case there are several inflatable channels 102 connected in series to be filled, the arrangement may be designed such that there is only a one-way valve located in the first channel to be filled which thus will function to keep all the channels connected in series to stay filled when the connected channels are filled. When a common chamber or manifold is used and connected to several channels, a similar valve arrangement may be used for the opening inlet to the common chamber or manifold such that the filling fluid may not escape the reverse way through the common chamber and the channels connected to the common chamber will also stay filled. One or several independent or series of interconnected linking conduits, channels and chambers may be used in the contact layer. Each of the series or parts of series of channels may have separate one-way valves. Even though it generally has been mentioned a multitude of channels 102 above could they be replaced for one single channel to be used.

[0051] The channels 102 may vary in size from being about 40 millimetres to 800 millimetres long and having a width of 1 to 100 millimetres. The height is in a range from 1 to 40 millimetres. Most commonly the channels vary in size from being about 40 millimetres to 400 millimetres long and having a width of 3 to 25 millimetres and a height in a range from 3 to 25 millimetres. It is generally considered that the height and width are essentially of the same dimensions or that the width may be larger than the height even though this is not necessary. The height and/or the width may vary along the longitudinal extension or be the same. In case the height and width are of essentially the same dimensions the channels will assume an essentially circular cross sectional area, i.e. having an essentially cylindrical shape, when inflated with the filling fluid. In case the width is greater than the height will the cross sectional area be more oval. The geometrical shape may also have other geometries all though these geometrical shapes described above will be natural to form when the channels are filled and pressurized with fluid. The volume of a channel is generally thought to be in the range from 0.020 ml to 30 ml. A channel having a volume of 0.02 ml corresponds essentially to a cylindrical chamber having a diameter of 1 mm and being 25 millimetres long while 20 ml corresponds to a cylindrical channel having a diameter of 10 mm and a length of about 250 millimetres. A cylindrical shaped channel having a diameter of around 5 millimetres and being 100 millimetres long will thus have a volume of about 2 ml. The channels may be straight or curved. The thin sheet 100 may have a thickness within the range of 0.01-1 mm. The thickness of the sheet is generally thought to be 0.01-0.2 mm. The walls of the chambers may have the same thickness. In practice, the walls of the channels 102 are preferably made from the same kind of material as the thin sheet 100. The thin sheet 100 and the chambers 102 may be made of plastics which may comprise polyurethane.

[0052] In FIGS. 3a to 3f different designs of the inflatable channel or channels 102 in the organ contact layer 16 are shown. The organ contact layer 16 is in general designed to have a circular or essentially circular shape. However, the shape could be altered, e.g. oval or asymmetrical, while still working perfectly well for the present invention and it is obvious for the skilled person to change the geometrical shape of the sheet 102 as desired. All the designs in FIGS. 3a to 3f are intended to address the issue of placing the organ contact layer adequately in the flanks and peripheral parts of the abdominal cavity and to secure this placement after deployment. The concept of all designs 3a to 3f are a system of channels 102, distribution chambers 110 and linking conduits 106 in the organ contact layer 16. The orientation of the channels 102, conduits 106 and chambers 110 are placed to enable filling of the channels 16 and thus increase the stability of the organ contact layer 16 in the direction desired. Designs 3b, 3d, 3e and 3f shows designs where the channels 102 are grouped in separate systems to enable sequential filling of different parts of the organ contact layer 16. All the designs in FIGS. 3a to 3f are possible to perforate to make the organ contact layer liquid permeable.

[0053] In FIG. 3a is disclosed a first design of the layout of the organ contact layer 16 in which eight channels 102 are located on a circular sheet 100. The channels 102 are stretching in a direction radially outwards from a distribution chamber 110 in the centre portion 108. The distribution chamber 110 comprises an inner circular chamber and two outer, ring shaped chambers located concentrically around the circular chamber. The chambers are connected to each other via four linking conduits 106, two linking conduits connects the circular chamber with the inner ring chamber and two other linking conduits connects the inner ring shaped chamber with the outer ring shaped chamber. The channels 102 are located equidistant and symmetrically around the centre portion 108 of the organ contact layer 16. Fluid may be injected into the circular chamber 110 by the use of an injection conduit 112 connected to the circular chamber 110. The injected fluid is distributed from the chambers 110 to the respective channels 102 via a respective opening 104 in each channel 102. The fluid to the longitudinally stretching channels will be distributed directly from the circular chamber, the fluid to the two transversally stretching channels will be distributed from the inner ring shaped chamber and the fluid to the 4 diagonally stretching channels will be distributed from the outer ring shaped chamber. The fluid is either directly distributed from a chamber 110 to a channel 102 or via linking conduits 106.

[0054] The distinction between what is referred to as a channel 102, a linking conduit 106 and a chamber 110 is mainly defined by its function. All these features represent spaces which are intended to be filled up with a fluid entering the system from the injection conduit 112.

[0055] However, the inflatable features have been defined herein with respect to their intended main function. Features referred to as a channel 102 are features that are designed to provide stability and rigidity to the organ contact layer 16. Elements referred to as linking conduits 106 are features that are designed to enable transport of the fluid between channels 102, between a channel 102 and a chamber 110 or between chambers 110. Elements referred to as chambers 110 are features that are designed to receive fluid and distribute the fluid to a multitude of channels 102, either by being in direct contact with an opening 104 in a connected channel 102 or via a linking conduit 106. A space may have one, two or all three of these functions, but are in this context referred to by their main function.

[0056] In FIG. 3b the layout is essentially the same but in this case there are 3 separate chambers 110a, 110b, 110c to which the fluid is injected. In addition, each of the longitudinal channels have been provided with an arc shaped segment which crosses the longitudinal channels about 1/3 of their lengths from the centre in a direction perpendicular to the extension direction of the longitudinal channels. The fluid is injected via three separate injection conduits 112a, 112b, 112c. The first chamber 110a is connected to circular channels 102a close to the centre portion 108 and longitudinal channels 102a which are intended to stretch along the length of a body when the organ contact layer 16 is positioned in the abdominal cavity of a person. The second chamber 110b is connected to three channels 102b which are stretching towards a first lateral side of a person when the organ contact layer 16 is placed in the abdominal cavity. The third chamber 110c is connected to the remaining three channels 102c stretching towards the other, second lateral side of a person when the organ contact layer 16 is placed in the abdominal cavity. Grouping of the channels 102a, b, c in this way makes it possible to first provide rigidity in the central portion of the organ contact layer 16 by filling the first chamber 110a and its connected channels 102a and thus stabilize this portion in a desired position. Thereafter, the first lateral side of the sheet, comprising the second group of channels 102b, may be unfolded and deployed in order to be provisionally located as desired before the second chamber 110b is filled and the fluid distributed to the second group of channels 102b. The first lateral side will thus have improved rigidity and stability facilitating deployment and securing placement. Finally, essentially the same procedure is performed with the other, second lateral side by placing the sheet and filling the third chamber 110c in order to provide an increased stability and rigidity by the third group of channels 102c.

[0057] In FIG. 3c a similar system as described in FIG. 3a is shown wherein the fluid is distributed to all channels 102 via a single injection conduit 112. However, the system has been provided with four further channels and the orientation of the channels 102 have been designed to extend more in the lateral direction, i.e. to extend in a direction from the central portion 108 towards the sides of person. By lateral direction is meant a direction perpendicular to the longitudinal extension of a person when the organ contact layer 16 is located as intended in the abdominal cavity of a person. This configuration is due to the problems with being able to keep the sides in the desired location when placing the organ contact layer 16 in the abdominal cavity. This design is intended to address particularly the issue of placing the organ contact layer adequately in the flanks and peripheral parts of the abdominal cavity and to secure this placement after deployment. Hence, it is in general most important to provide rigidity in the lateral direction. These basic ideas for designing the layout of the channels in FIG. 3c could of course also be used for changing the geometrical configuration and extension direction of the channels 102 in FIG. 3a and channels 102a, 102b, 102c in the arrangement in FIG. 3b to have channels with more transversal extension.

[0058] In FIG. 3d an arrangement similar to the one described in FIG. 3b is shown but with the difference that each of the injection conduits 112a, 112b, 112c have been provided with a respective one-way valve 114a, 114b, 114c. These valves will thus prevent the fluid in the injection conduits 112a, 112b, 112c to flow in the reverse direction and hence enables pressure to be maintained in the chambers 110a, 110b, 110c and its associated group of channels 102a, 102b, 102c. Such valves could of course also be included in the arrangements described in FIGS. 3a to 3c.

[0059] In FIG. 3e another arrangement is shown which reminds of the layout in FIGS. 3b and 3d by having groups of channels 102a, 102b 102c which may be filled separately. In this arrangement the elongated channels have been provided with low burst pressure valves 116 such that the complete channels will not be filled unless the injected fluid rises above a certain pressure. Hence, by controlling the pressure at injection it will be possible to select if the complete channels of the same group shall be filled or if it is desired only a portion shall be filled. The same arrangement with valves having low burst pressures can be use between sections in the organ contact layer as an alternative to sections that are totally separated. The same arrangement with low-pressure burst valves could of course be used in all designs 3a to 3d.

[0060] In FIG. 3f still another arrangement is disclosed in which essentially all channels 102 are designed to be in the lateral direction, i.e. in a direction perpendicular to the length direction of a person when the contact layer is placed in the abdominal cavity as intended. The channels have been divided in two groups, 102d and 102e. To the first group of channels 102d, which essentially comprises channels extending from the centre of the contact layer 16 towards a first lateral side, is also included a centrally positioned semi-circular channel. This arrangement thus provides for inflating the central portion and one side at the same time to be stabilized. When the contact layer 16 has been provisionally adjusted in the central region and at one side these channels 102d could be inflated. Thereafter may the other lateral side comprising channels 102e be provisionally located where after also channels 10e may be inflated to stabilize the fluid transport sheet 16. It shall be noted that even though the channels of both groups are essentially aligned in a transversal direction (except for the central semi-circular channel) is the configuration of the channels 102a, 102b in this example non-symmetrical and the channels have different lengths with no particular symmetry. This is disclosed in this way in order to make it clear that there is no need to make the channels disclosed herein in a symmetrical pattern. There may be advantages in providing an asymmetrical pattern due to the asymmetrical shape of a human body and the unpredictable exact configuration of a human body. It may for example be advantageous to have the different sides being different such that the configuration of the contact layers channels, and thus rigid zones, will change as the transport dressing is rotated 180 degrees. For example, one side may be wider (having longer channels for one lateral side). Hence, the channel patterns in the embodiments disclosed in FIGS. 3a to 3f may also be designed to be less symmetric. In addition, it may be desired to have different cross sectional size of different channels.

[0061] One should note that only the main characteristics have been discussed concerning these examples of an organ contact layer. For example, all the above described organ contact layer may be made liquid permeable by providing slits or holes in the sheet. There may of course be further channels included in the contact layer and the layout and design could also be different. In the examples above is only disclosed that one channel, all channels, 2 groups or 3 or a larger number of groups of channels will be filled at the same time. It could of course be possible to group the channels as desired and use more groups or even have each channel being independently controlled to be filled. Hence, all these embodiments only show a few examples of possible configurations and arrangement of inflatable channels in an organ contact layer.

[0062] All the above designs can be achieved by using a single thin sheet 100 or a top sheet and a bottom sheet and having the channels 102 interposed between these sheets. All the above designs could also be used in a single sheet with the channels 102 welded to this sheet 100. This design could for example be used for integrating the channels 100 in an organ contact layer as disclosed in WO 2014/202560, which hereby is incorporated by reference, and will be described next with reference to FIG. 4.

[0063] In FIG. 4 is disclosed an alternative design of the organ contact layer 16 in which the single sheet 100 described in FIG. 2 has been replaced with a top sheet 30 and a bottom sheet 32. As described for FIG. 2, the organ contact layer 16 may have a planar extension in a first plane and the organ contact layer may also extend in a vertical direction V that is perpendicular to the extension of the first plane . At least one, alternatively both, of the top and bottom sheets 30, 32 may be of a plastics material which may comprise polyurethane. In this design, the organ contact layer 16 has been provided with sealed chambers 28 in addition to the inflatable chambers 102. The sealed chambers 28 and the inflatable chambers 102 are located between the top and bottom sheets 30, 32. The sealed chambers 28, and the inflatable chambers 102, are at least partially delimited by an intermediate sheet 34 that extends at least partially between the top and bottom sheets 30, 32. The intermediate sheet 34 may be deformed, for instance pleated, and thereafter attached to at least one of the top and bottom sheets 30, 32 such that the sealed chambers 28 and/or the inflatable channels 102 are formed. The intermediate sheet 34 may be attached to both the top and bottom sheets 30, 32 such that a continuous organ contact layer 16 is obtained.

[0064] Purely by way of example, each one of the sealed chambers encloses a volume of at least 0.010 ml. Alternatively, each one of the sealed chambers encloses a volume of at least 0.050 ml. As another non-limiting option, each one of the sealed chambers encloses a volume of at least 0.080 ml.

[0065] In other non-limiting examples of a sealed chamber, the sealed chamber may have a substantially cylindrical shape with a height, i.e. an extension in a direction perpendicular to the planar extension of the top sheet 30 and/or the bottom sheet 32, and a diameter in the planar extension. Purely by way of example, the height of a sealed chamber may be within the range of 0.3-0.7 of the diameter of the sealed chamber. The channels 102 may be of the dimensions earlier discussed and the sealed chambers 28 and the channels 102 may be adapted to each other such that they have equal height.

[0066] Purely by way of example, the sealed chamber may have a diameter that is one of the following: 3, 6, 9 or 25 mm. Assuming, as a non-limiting example, that the height of the sealed chamber is approximately half the diameter of the sealed chamber, the volume of the sealed chamber is approximately 0.010 ml for a sealed chamber with a diameter of 3 mm, approximately 0.080 ml for a sealed chamber with a diameter of 6 mm, approximately 0.28 ml for a sealed chamber with a diameter of 9 mm and approximately 6.0 ml for a sealed chamber with a diameter of 25 mm.

[0067] As a non-limiting example, the intermediate sheet 34 may be of a plastics material which may comprise polyurethane. Instead of, or in addition to polyurethane, at least one, alternatively two or more, of the top, bottom and intermediate sheets 30, 32, 34 may comprise at least one of the following materials: other types of urethanes, silicone, transparent hydrocolloid, PVC, hydrogel, copolyester, polyethylene, TPS (thermoplastic elastomers based on styrene) or TPO (thermoplastic olefins) i.e. blends of polyethylene and polypropylene.

[0068] Purely by way of example, each one of the top and bottom sheets 30, 32 as well as the intermediate sheet 34 may have a thickness within the range of 0.01-1 mm.

[0069] In a specific embodiment could the contact layer 16 be manufactured such that it essentially only has what appears to be sealed chambers 28 when the dressing 16 is manufactured. There are however a few chambers 28 which has been adapted with an inlet opening 104, either being void or having a one-way valve at the inlet opening. The contact layer could be manufactured such that a group of sealed chambers 28 have been prepared to release the attachment of intermediate walls when subjected to an elevated pressure. This design could thus enable a contact layer 16 which appears only to have a multitude of small sealed chambers 28 to form larger channels 102 by injecting a fluid into these special chambers 28 which is adjacent to a group of sealed chambers which are designed such that their intermediate walls will collapse and they will form a large channel together when fluid is injected. The collapse may for example be made, if a design using a top sheet 30, bottom sheet 32 and intermediate sheet 34, by designing the intermediate sheet 34 to have a weaker attachment to the top sheet 30 and/or bottom sheet 32 at predefined locations such that it will detach in a controlled manner and a group of sealed chambers will form an inflatable channel.)

[0070] FIG. 5 illustrates a top view of how a contact layer 16 could be designed having sealed chambers 28 and inflatable chambers 102a, 102b, 102c. The layout may for example be used for the contact layer 16 of which a portion is disclosed in FIG. 4. In practice, there should probably be more sealed chambers than what is disclosed in this figure. In case the transport dressing is made as disclosed in FIG. 4 can it be seen that fluid conduits 38 will be formed between rows of sealed chambers 28 and/or inflatable channels 102a, 102b, 102c. These channels 102a, 102b, 102c could either be designed to be channels when manufactured or be formed by interconnecting a row of specifically designed sealed chambers 28 which are designed to rupture their side walls when subjected to an increased pressure and thereby interconnect with each other and form a large inflatable channel 102 together.

[0071] If this layout described in FIG. 5 is used for the dressing described in FIG. 4 it further indicates a plurality of fluid conduits 38. The sealed chambers 28 are arranged such that at least a plurality of the fluid conduits 38 extend from the periphery 40 of the contact layer 16 towards the centre 108 thereof. However, in other embodiments of the contact layer 16, the sealed chambers 28 may be arranged in other ways. For example, the sealed chambers 28 may be spaced evenly throughout the contact layer.

[0072] In FIG. 6 is disclosed an example in which the organ contact layer 16 has been provided with slits 48 in order to make permeable to liquids. In case a double sheet structure is used as disclosed in FIG. 4 should of course both sheets be provided with slits 48 in order to make the organ contact layer readily permeable to fluids.