AU2007276774A1 - Patient support with welded materials - Google Patents

Description

WO 2008/014277 PCT/US2007/074249 DESCRIPTION PATIENT SUPPORT WITH WELDED MATERIALS Cross-References to Related Applications This application claims priority to U.S. Provisional Patent Application 5 No. 60/833,460, filed July 26, 2006, which is incorporated by reference herein without disclaimer. Field of the Invention The present disclosure relates generally to systems and methods for 10 supporting patients or other persons, and more particularly but not by way of limitation to systems and methods for supporting patients or other persons with materials that have been coupled or joined by welding. Background 15 Patient support surfaces, including therapeutic surfaces, are common in medical settings such as hospitals, clinics, and patients' homes, among other places. Some surfaces (commonly referred to as "low air loss" surfaces) include inflatable enclosures that flow air through air permeable 20 materials adjacent to the patient in an effort to prevent or treat pressure ulcers. The treatment and/or prevention of pressure ulcers are serious and expensive issues in the health care industry. Pressure ulcer development is related, in part, to the accumulation of heat and perspiration on the skin. Heat 25 and moisture increase skin susceptibility to the damaging effects of pressure and shear and decrease the resiliency of the epidermis to external forces. Ongoing compressive forces on skin tissues are known to promote ischemia with subsequent development of pressure ulcers. Therefore, controlling the microclimate of the skin and providing a quality patient support system appear 30 to be necessary to prevent pressure ulcers. Low-air-loss (LAL) broadly refers to a system comprising a mattress casing, a vapor permeable coverlet with or without lofting or cushioning material, and an air delivery system to move air under the coverlet and, in 1 WO 2008/014277 PCT/US2007/074249 some cases, to leak through the coverlet. Some LAL mattress systems function as integral parts of patient support systems; whereas, others are not actively coupled. Currently, low-air-loss (LAL) mattress systems are the most prevalent 5 tools used for pressure ulcer treatment and prevention. LAL mattress systems were developed and are used in the belief that they help to control the microclimate of the skin. These systems have been found to be highly effective in treating and/or preventing pressure ulcers. Certain support surfaces comprise more than one material, with each 10 material having different air, vapor, and liquid permeability properties. For example, it may be desirable to have a vapor permeable material adjacent to the patient's skin to allow moisture vapor to transfer away from the patient and into the support surface. It may also be desirable to have an air permeable material adjacent to the patient's skin to allow air to flow proximal to the 15 patient and assist in removing moisture vapor from the patient and the support surface. Furthermore, it may be desirable for portions of the support surface to be air impermeable in order to restrict air flow and minimize power requirements and noise levels for the support system. For hygienic reasons, it may be desirable that the support surface comprise a liquid impermeable 20 material. LAL mattresses typically include a foundation of a series of interconnected air cells that allow air to flow through and exit the mattress. Other common elements include an adjustable pump that can maintain air inflation of the air cells. In addition to the mattress, the LAL mattress system 25 also includes the coverlet (waterproof and/or vapor permeable), and coverlet lofting material (e.g., quilted polyester fabric batting) that attach over the mattress. The coverlet is typically made of one or more materials that are permeable to moisture, is impermeable to bacteria, and is waterproof. Coverlets also function to prevent excessive loss of body heat, have high 30 moisture vapor permeability to minimize/prevent the accumulation of perspiration on the skin, and have high air porosity for removal of excessive body heat through a continuous airflow provided by the LAL mattress. Together, the LAL mattress and the coverlet form the LAL mattress system. 2 WO 2008/014277 PCT/US2007/074249 The LAL mattress can further include a fabric cover over the foundation (i.e., the air cells). In some cases, this fabric cover is formed from a GORE TEXo fabric that is formed integrally with the air cells. The GORE-TEX® fabric is liquid impermeable and has significantly higher air-permeable and vapor 5 permeable characteristics as compared to urethane-backed nylon materials used in other mattresses. The GORE-TEX® fabric moisture vapor transfer characteristics help to prevent or speed up healing of pressure ulcers in patients by reducing the amount of moisture buildup on the skin and by helping to keep patients cooler by allowing body heat to more easily escape. 10 It is therefore desirable to construct a support surface from different types of materials. As a result, it is often necessary to couple or join different types of material used to form the support surface. Summary Exemplary embodiments of the present disclosure are directed to 15 apparatus, systems, and methods to support a patient or other person. Exemplary embodiments comprise a first air impermeable material welded to a second material that is air permeable and liquid impermeable. In exemplary embodiments, the first material is liquid and vapor impermeable and the second material is vapor permeable. In exemplary embodiments, an 20 inflatable enclosure is formed from a sheet of the first material with an aperture, and the second material covers a portion of the aperture. In other exemplary embodiments, an inflatable enclosure may be formed by several individual panels of the first material welded to a panel of the second material. Exemplary embodiments comprise a support member comprising an 25 inflatable enclosure having a first material and a second material, wherein the first material is substantially air impermeable, the second material is air permeable and substantially liquid impermeable, and the second material is welded to the first material. In exemplary embodiments, the first material comprises an aperture and the second material covers a portion of the 30 aperture. In other exemplary embodiments, the second material is high frequency (HF) welded to the first material. In still other exemplary embodiments, the second material is vapor permeable. Certain exemplary embodiments comprise an internal baffle. In still other exemplary embodiments, the first material is urethane. Certain exemplary embodiments 3 WO 2008/014277 PCT/US2007/074249 comprise an opening configured to be coupled to a source of pressurized fluid. Other exemplary embodiments comprise an apparatus for supporting a person, comprising: a sheet comprising a first material, wherein the first 5 material is substantially air impermeable; an aperture in the sheet; a second material covering the aperture, wherein the second material is air permeable and substantially liquid impermeable and the second material is welded to the first material. In certain exemplary embodiments, the sheet comprises a first end, a second end, a first side and a second side; the first side is coupled to 10 the second side; the first end is sealed; and the second end is sealed, so that the sheet is configured to form an elongated inflatable enclosure. In exemplary embodiments, the sheet is configured to form a generally cylindrical enclosure when inflated. Certain exemplary embodiments comprise an internal baffle, wherein the elongated inflatable enclosure has a 15 cross-section having a height and a width, wherein the height is greater than the width. In exemplary embodiments, the second material is high frequency (HF) welded to the first material. In certain exemplary embodiments, the second material is vapor permeable and/or the first material is urethane. In certain exemplary embodiments, the sheet comprises an opening configured 20 to be coupled to a source of pressurized fluid. Other exemplary embodiments comprise a support system comprising: a plurality of first and second support members, wherein the first support members are a first height and comprise a first material that is substantially air impermeable and the second support members are a second height and 25 comprise a second material that is air permeable and substantially liquid impermeable. In exemplary embodiments, the first height is greater than the second height and a second support member is located between two first support members. In exemplary embodiments, the second material is vapor permeable. In certain exemplary embodiments, the first support members 30 comprise a vapor permeable and liquid impermeable third material. In other exemplary embodiments, a first source of pressurized fluid is coupled to the first support member and coupled to the second support member. In still other exemplary embodiments, a first source of pressurized fluid is coupled to 4 WO 2008/014277 PCT/US2007/074249 the first support member and a second source of pressurized fluid is coupled to the second support member. Other exemplary embodiments comprise a method of manufacturing a support member, the method comprising: providing a sheet of first material, 5 wherein the first material is air impermeable; creating an aperture in the sheet; covering a portion of the aperture with a second material, wherein the second material is air permeable and liquid impermeable; welding the second material to the first material; and configuring the sheet to form an inflatable enclosure. In exemplary embodiments, the second material is high frequency welded to 10 the first material. Brief Description of the Fiqures While exemplary embodiments of the present invention have been shown and described in detail below, it will be clear to the person skilled in the 15 art that changes and modifications may be made without departing from the scope of the invention. As such, that which is set forth in the following description and accompanying figures is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined by the following claims, along with the full range of equivalents to which such 20 claims are entitled. In addition, one of ordinary skill in the art will appreciate upon reading and understanding this disclosure that other variations for the invention described herein can be included within the scope of the present invention. For example, exemplary embodiments are disclosed with a single sheet 25 configured to form an inflatable enclosure. In other exemplary embodiments, the inflatable enclosure may comprise multiple panels coupled to form an inflatable enclosure. For example, exemplary embodiments may comprise an inflatable enclosure with separate top, bottom, side and end panels. In the following Detailed Description of Disclosed Embodiments, 30 various features are grouped together in several embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that exemplary embodiments of the invention require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less 5 WO 2008/014277 PCT/US2007/074249 than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description of Disclosed Embodiments, with each claim standing on its own as a separate embodiment. 5 The following Figures are referenced herein. The Figures illustrating the exemplary embodiments are not to scale. Figure 1 provides a top view of one exemplary embodiment of a support system component according to the present disclosure. Figure 2 provides a side view of one exemplary embodiment of a 10 support member according to the present disclosure. Figure 3 provides a cross-section view of one exemplary embodiment of a support member according to the present disclosure. Figure 4 provides an end view of one exemplary embodiment of a support member according to the present disclosure. 15 Figure 5 provides a top view of one exemplary embodiment of a support system component according to the present disclosure. Figure 6 provides a side view of one exemplary embodiment of a support member according to the present disclosure. Figure 7 provides a cross-section view of one exemplary embodiment 20 of a support member according to the present disclosure. Figure 8 provides an end view of one exemplary embodiment of a support member according to the present disclosure. Figure 9 provides a top view of a one exemplary embodiment of a support system according to the present disclosure. 25 Figure 10 provides a side view of a one exemplary embodiment of a support system according to the present disclosure. Detailed Description of Exemplary Embodiments 30 Exemplary embodiments of the present disclosure are directed to an apparatus that functions as a patient support surface or therapeutic surface formed from multiple materials that exhibit various properties and are joined at various locations using a welding technique to produce a biologically sealed and controlled air loss surface. In certain exemplary embodiments, the 6 WO 2008/014277 PCT/US2007/074249 welding technique used to couple or join the materials is a high frequency (HF) welding technique. The materials may comprise varying properties, including liquid, vapor, and air permeability, as well as friction coefficients. For example, in exemplary embodiments of the present disclosure, HF 5 welding, also referred to as dielectric welding or radio frequency (RF) welding can be used to join a urethane based material to a polytetrafluoroethylene (PTFE or Teflon) -based material such as GORE-TEX®, to form a support cushion having low-air-loss features, antimicrobial features, structurally sound features, and controlled air loss features, among others. 10 High frequency welding is a process that uses high frequency radio energy to produce molecular agitation, and therefore heat, in various types of materials so as to fuse the materials together. Thus, in various embodiments, materials used to form support surfaces and therapeutic surfaces of the present disclosure that are capable of being HF welded are contemplated and 15 are not limited to urethane based materials and Teflon based materials such as GORE-TEX®. Exemplary embodiments of the process involve subjecting the materials to be fused or joined to a high frequency (between -13 and -100MHz) electromagnetic field, which is normally applied between two metal 20 surfaces (e.g., metal bars). These surfaces also function as pressure applicators during heating and cooling. The electromagnetic field causes the molecules in polar thermoplastics to oscillate and thus, depending on their geometry and dipole moment, these molecules may translate some of this oscillatory motion into thermal energy and cause heating of the material and 25 eventually, the joining or fusing of the material. HF welding is useful for joining polymers that have strong dipoles, such as polyvinyl chloride (PVC), polyurethanes, and polyamides, among others. It is possible to RF weld other polymers including nylon, Polyethylene Terephthalate (PET), Ethylene Vinyl Acetate (EVA) and some Acrylonitrile 30 Butadiene Styrene (ABS) resins, among others. In various exemplary embodiments, other forms of welding are also contemplated. Hot gas welding, hot plate welding, ultrasonic welding, vibration or friction welding, laser welding, and solvent welding, among others may be implemented. As one of ordinary skill in the art will appreciate, some of these 7 WO 2008/014277 PCT/US2007/074249 forms of welding might be more conducive to welding various plastics and other materials than other forms of welding and thus, the types of materials to be welded to form a patient support surface and/or therapeutic surface of the present disclosure can be chosen based upon the form of welding desired or 5 vice versa. The Figures herein follow a numbering convention in which the first digit or digits correspond to the drawing Figure number and the remaining digits identify an element or component in the drawing. Similar elements or components between different Figures may be identified by the use of similar 10 digits. For example, an element in Figure 1 may be referenced as 110, and a similar element may be referenced as 210 in Figure 2. As will be appreciated, elements shown in the various exemplary embodiments herein can be added, exchanged, and/or eliminated so as to provide any number of additional embodiments of the support members and support systems of the present 15 disclosure. Referring now to Figure 1, a sheet 102 comprises an aperture 106. In the exemplary embodiment shown in Figure 1, sheet 102 comprises a first end 151, a second end 152, a first side 153, and a second side 154. In exemplary embodiments, sheet 102 is comprised of a substantially air 20 impermeable material. In a particular exemplary embodiment, sheet 102 is comprised of a material that is also substantially vapor and liquid impermeable, such as urethane-backed nylon. As shown in Figure 1, a material 104 covers aperture 106 (or a portion thereof). In exemplary embodiments, material 104 is substantially air permeable. In certain 25 exemplary embodiments, material 104 may be a substantially vapor permeable and liquid impermeable material comprising PTFE, such as GoreTex®. In the exemplary embodiment shown in Figure 1, material 104 is welded to sheet 102 around the perimeter of aperture 106. In particular 30 exemplary embodiments, material 104 is welded to sheet 102 via a high frequency welding process. In the exemplary embodiment shown, sheet 102 comprises an opening 110 which maybe connected to a source (not shown) of pressurized air or other fluid. 8 WO 2008/014277 PCT/US2007/074249 In exemplary embodiments, material 104 may be sized so that it is slightly larger than aperture 106 and overlaps sheet 102 at the perimeter of aperture 106. In such exemplary embodiments, material 104 may be lap welded to sheet 102. In other exemplary embodiments, material 104 may be 5 sized so that it is substantially the same size as aperture 106. In such exemplary embodiments, a ring of backing material (not shown) may be placed at the junction of material 104 and sheet 102 to allow a butt-weld to be formed between material 104 and sheet 102. In certain exemplary embodiments, the backing material may be comprised of the same material 10 as sheet 102. In the exemplary embodiment shown in Figure 1, aperture 106 is approximately centered between first side 153 and second side 154. In the exemplary embodiment shown in Figure 1, aperture 106 also extends along a majority of the length of sheet 102. 15 Referring now to Figures 2 and 3, sheet 102 can be configured to form a support member 100 that can be inflated with air or another pressurized fluid. In the exemplary embodiment shown in Figures 2 and 3, sheet 102 has been arranged so that first side 153 is coupled to second side 154. In addition, first end 151 and second end 152 have been sealed so that sheet 20 102 forms an elongated enclosure. In exemplary embodiments, first side 153 is coupled to second side 154 via welding to form a flat seam weld 114 and first end 151 and second end 152 are sealed via welding to form a pair of flat seam welds 112. In certain exemplary embodiments, first side 153 is high frequency welded to second side 154 and first end 151 and second end 152 25 are sealed via high frequency welding. In exemplary embodiments, opening 110 can be connected, for example, to an air pump (not shown) to move air into the support member 100 to both inflate the support member 100 and to maintain a partial pressure difference of vapor and thus, aid in moisture and heat removal from the patient and from the environment surrounding the 30 patient. Figure 3 illustrates a cross-section of Figure 2 taken at section line 3-3. As shown in the exemplary embodiment of Figure 3, support member 100 may incorporate a baffle 116 that extends across support member 100. In this exemplary embodiment, each end of baffle 116 is coupled to sheet 102 so 9 WO 2008/014277 PCT/US2007/074249 the cross-section of support member 100 is narrower than it is high. In the exemplary embodiment shown in Figure 3, baffle 116 is sized so that the cross-section of support member generally forms an hourglass or "figure-8" shape with an indentation 117 at each side of support member 100. The 5 incorporation of baffle 116 provides a narrower cross-section for support member 100 and allows for a greater number of support members 100 to be incorporated into a patient support system. Figure 4 illustrates an end view of an exemplary embodiment of a support member 101 that does not incorporate a baffle. As shown, the cross 10 section of support member 100 in Figure 4 is a generally circular shape. Other features are generally equivalent to those disclosed in the discussion of Figure 3. Referring now to Figures 5-8, an exemplary embodiment of a support member 200 comprises a lower portion 205 with a cap or upper portion 210. 15 Exemplary embodiments of support member 200 are similar to those of support member 100. However, exemplary embodiments of support member 200 comprise a material 204 that is substantially air impermeable, rather than the air permeable material 104 used in support member 100. In exemplary embodiments, material 204 is also vapor permeable and liquid impermeable. 20 In addition, exemplary embodiments of support member 200 comprise an aperture 206 that is larger than aperture 106 of support member 100. In exemplary embodiments, aperture 204 extends substantially across the entire length of support member 200 so that it is proximal to first end 251 and second end 252. 25 Similar to the construction techniques used to form support member 100, exemplary embodiments of support member 200 may be formed by welding a first side 253 to a second side 254 and sealing first and second ends 251 and 252. Material 204 may also be welded to sheet 202 to cover aperture 206 in exemplary embodiments. 30 In other embodiments, support member 200 may be constructed in other manners. For example, support member 200 may comprise separate pieces of material, rather than a single sheet 202 with an aperture 206. In the exemplary embodiment shown in Figure 7, sheet 202 has been formed into a support member with an hourglass or "figure-8" cross-section. 10 WO 2008/014277 PCT/US2007/074249 In this exemplary embodiment, support member 202 incorporates a baffle 216. As shown in the exemplary embodiment of Figure 8, sheet 202 may also be formed into a support member 201 that is generally cylindrical with a circular cross section in certain exemplary embodiments. 5 Referring now to Figures 9 and 10, an exemplary embodiment of a support system 300 comprises a first set of support members 100 and a second set of support members 200. As shown in the top view of Figure 9, support members 100 and 200 are arranged in a generally alternating configuration so that a support member 100 is located between two support 10 members 200. Support members 100 and 200 may be inflated with pressurized air or another source of fluid. As shown in the partial side view of the exemplary embodiment in Figure 10, support members 200 are taller than support members 100. In exemplary embodiments, support members 200 are comprised of material 15 202 that is substantially air impermeable with a cap of material 204 that is air impermeable and vapor permeable. In exemplary embodiments, support members 100 comprise a material 102 that is air impermeable and a cap of material 104 that is air permeable and liquid impermeable. In exemplary embodiments, support members 200 will provide primary support for a person 20 (not shown) laying on support member 300. In exemplary embodiments, air can flow through support members 100 and exit material 104 covering aperture 106. Such air flow can assist in transferring moisture vapor from a person's body as they lay on support system 300. Air flow may also assist in removing moisture vapor from support members 100. 25 In exemplary embodiments, moisture vapor may transfer from a person through material 204 and into support member 200. In the exemplary embodiment shown in Figure 9, material 204 extends nearly to edges 305 and 310 of support system 300. Therefore, a significant portion of material 204 will not be in contact with a person laying on support system 300. As a result, 30 moisture vapor can also exit support member 200 via material 204. In exemplary embodiments, increasing the area covered by material 204 will increase the rate at which moisture vapor can be transferred from a person being supported by support system 300. 11 WO 2008/014277 PCT/US2007/074249 In the exemplary embodiment shown in Figures 9 and 10, support system 300 is configured to reduce the amount of air flow needed to support a person and provide moisture vapor transfer capabilities. Primary support is provided by support members 200, which comprise material that is 5 substantially air impermeable, and therefore requires minimal air flow to remain inflated and provide support. Support members 100 comprise material 104 which is air permeable and therefore requires more airflow than support members 200 to stay inflated. The amount of air (or other pressurized fluid) required to inflate support members 100 and 200 can be reduced because the 10 air flow is restricted to areas covered by material 104. In addition, the power requirements and noise levels of equipment needed to inflate support members 100 and 200 are also reduced. In certain exemplary embodiments, support members 100 may be coupled to one source of pressurized fluid and support members 200 may be coupled to a second source of pressurized 15 fluid. In such exemplary embodiments, each source of pressurized fluid can be configured to the operating parameters required. For example, the source of pressurized fluid for support members 100 may be a lower pressure, higher volume source than the source of pressured fluid for support members 200. In exemplary embodiments, support members 100 and 200 can be 20 welded together to form the contiguous patient support surface system 300. In other embodiments, the support members 100 and 200 can be enclosed by a cover (not shown) to form the contiguous patient support surface 300. While exemplary embodiments have been shown and described in detail above, it will be clear to the person skilled in the art that changes and 25 modifications may be made without departing from the scope of the invention. As such, that which is set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as a limitation. The actual scope of the invention is intended to be defined by the following claims, along with the full range of equivalents to which such claims are entitled. 30 In addition, one of ordinary skill in the art will appreciate upon reading and understanding this disclosure that other variations for the invention described herein can be included within the scope of the present invention. For example, the patient support surface can be coated with an antimicrobial agent, as are known or will be known. 12 WO 2008/014277 PCT/US2007/074249 In the foregoing Detailed Description, various features are grouped together in several embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the embodiments of the invention require more features than are 5 expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claims standing on its own as a separate embodiment. 13

Claims (40)

1. A support member comprising: an inflatable enclosure comprising a first material and a second material, wherein: the first material is substantially air impermeable; the second material is air permeable and substantially liquid impermeable; and the second material is welded to the first material.

2. The support member of claim 1 wherein the first material comprises an aperture and the second material covers a portion of the aperture.

3. The support member of claim 1, wherein the second material is high frequency (HF) welded to the first material.

4. The support member of claim 1 wherein the second material is vapor permeable.

5. The support member of claim 1, further comprising an internal baffle.

6. The support member of claim 1 wherein the first material comprises urethane and the second material comprises polytetrafluoroethylene.

7. The support member of claim 1 further comprising an opening configured to be coupled to a source of pressurized fluid.

8. An apparatus for supporting a person, the apparatus comprising: a sheet comprising a first material, wherein the first material is substantially air impermeable; an aperture in the sheet; a second material covering the aperture, wherein the second material is air permeable and substantially liquid impermeable and the second material is welded to the first material.

9. The apparatus of claim 8 wherein: the sheet comprises a first end, a second end, a first side and a second side; 14 WO 2008/014277 PCT/US2007/074249 the first side is coupled to the second side; the first end is sealed; and the second end is sealed, so that the sheet is configured to form an elongated inflatable enclosure.

10. The apparatus of claim 9, wherein the sheet is configured to form a generally cylindrical enclosure when inflated.

11. The apparatus of claim 9 further comprising an internal baffle, wherein the elongated inflatable enclosure has a cross-section having a height and a width, wherein the height is greater than the width.

12. The apparatus of claim 8 wherein the second material is high frequency (HF) welded to the first material.

13. The apparatus of claim 8 wherein the second material is vapor permeable.

14. The apparatus of claim 8 wherein the first material comprises urethane and the second material comprises polytetrafluoroethylene.

15. The apparatus of claim 8 wherein the sheet comprises an opening configured to be coupled to a source of pressurized fluid.

16. A support system comprising: a plurality of first support members, wherein: the first support members comprise a first material that is substantially air impermeable; and the first support members are a first height; and a plurality of second support members, wherein: the second support members comprise a second material that is air permeable and liquid impermeable; the second support members are a second height; the first height is greater than the second height; and 15 WO 2008/014277 PCT/US2007/074249 a second support member is located between two first support members.

17. The support system of claim 16 wherein the second material is vapor permeable.

18. The support system of claim 16, wherein the first support members comprise a third material and the third material is vapor permeable and liquid impermeable.

19. The support system of claim 16, further comprising a first source of pressurized fluid coupled to the first support member and coupled to the second support member.

20. The support system of claim 16, further comprising a first source of pressurized fluid coupled to the first support member and a second source of pressurized fluid coupled to the second support member.

21. A method of manufacturing a support member, the method comprising: providing a sheet of first material, wherein the first material is air impermeable; creating an aperture in the sheet; covering a portion of the aperture with a second material, wherein the second material is air permeable and liquid impermeable; welding the second material to the first material; and configuring the sheet to form an inflatable enclosure.

22. The method of claim 21 wherein the second material is high frequency welded to the first material.

23. A support member comprising: an inflatable enclosure comprising a first material and a second material, wherein: the first material is substantially air impermeable; the second material is air permeable and substantially liquid impermeable; and the second material is welded to the first material. 16 WO 2008/014277 PCT/US2007/074249

24. The support member of claim 23 wherein the first material comprises an aperture and the second material covers a portion of the aperture.

25. The support member of any of claims 23-24, wherein the second material is high frequency (HF) welded to the first material.

26. The support member of any of claims 23-25, wherein the second material is vapor permeable.

27. The support member of any of claims 23-26, further comprising an internal baffle.

28. The support member of any of claims 23-27, wherein the first material comprises urethane and the second material comprises polytetrafluoroethylene.

29. The support member of any of claims 23-28, further comprising an opening configured to be coupled to a source of pressurized fluid.

30. The support member of any of claims 23-29, wherein: the first material forms a sheet; the sheet comprises an aperture; and the second material covers the aperture.

31. The support member of claim 30 wherein: the sheet comprises a first end, a second end, a first side and a second side; the first side is coupled to the second side; the first end is sealed; and the second end is sealed, so that the sheet is configured to form an elongated inflatable enclosure.

32. The support member of any of claims 30-31, wherein the sheet is configured to form a generally cylindrical enclosure when inflated.

33. The support member of any of claims 30-32, wherein the elongated inflatable enclosure has a cross-section having a height and a width, wherein the height is greater than the width.

34. The support member of any of claims 30-33, wherein the sheet comprises an opening configured to be coupled to a source of pressurized fluid. 17 WO 2008/014277 PCT/US2007/074249

35. A support system comprising a plurality of first support members of any of claims 23-34 and a plurality of second support members, wherein: the first support members are a first height; the second support members comprise an air permeable and liquid impermeable material; the second support members are a second height; the first height is greater than the second height; and at least one second support member is located between two first support members.

36. The support system of claim 35 wherein the second support member's air permeable and liquid impermeable material is also vapor permeable.

37. The support system of any of claims 35-36, further comprising a first source of pressurized fluid coupled to a first support member and coupled to a second support member.

38. The support system of any of claims 35-36, further comprising a first source of pressurized fluid coupled to the first support member and a second source of pressurized fluid coupled to the second support member.

39. A method of manufacturing a support member of any of claims 23 34, the method comprising: providing a sheet of the first material; creating an aperture in the sheet; covering a portion of the aperture with the second material; welding the second material to the first material; and configuring the sheet to form an inflatable enclosure.

40. The method of claim 39 wherein the second material is high frequency welded to the first material. 18