Abstract:
A system for temporary abdominal or thoracic closure provides an expanded folded section allowing shielding of the wound from contamination and visual inspection while relieving abdominal pressure.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is based on and claims the benefit of U.S. Provisional Application 60/511,441, filed Oct. 15, 2003. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to surgical temporary wound closure devices and the method of using such a device for temporary abdominal and thoracic closure. .  
         [0003]     Some abdominal surgery emergencies, especially for trauma and infectious conditions, cannot be solved with a single operation, and multiple re-operations are required.  
         [0004]     Trauma, infection, hemorrhage, a ruptured aortic abdominal aneurysm repair, or other catastrophic abdominal events may lead to increased intra-abdominal pressure, which is a life threatening condition if not treated by opening or leaving the abdominal wall open until the increased pressure subsides. Swelling may also accompany some thoracic surgeries which prevents closure immediately following the surgery.  
         [0005]     A common surgical practice for leaving an abdomen open is to cover it with a large piece of plastic which is typically cut from an IV or urinary bag. This piece of plastic is sterilized, cut to size, and then sewn to the periphery of the abdominal wall opening and left in place between operations or until the swelling subsides.  
         [0006]     One of the characteristics of the IV or urinary bag closure is that it does not expand in response to further increases in intra-abdominal pressure. In order to avoid some of these problems, temporary closure methods allowing repeated fastening and refastening with adjustable separation have been developed. One such device is described in PCT application: WO9009763A1 entitled Wound Closing Method and Device, filed Feb. 26, 1990. Such closure methods require periodic opening of the closure device to inspect the wound and to change the separation of the wound edges to control intra-abdominal pressure.  
       BRIEF SUMMARY OF THE INVENTION  
       [0007]     The present invention provides a closure system providing a continuous sheet of sterile, biocompatible material which covers an abdominal or thoracic opening. The outer edges of the sheet may be attached to the edges of the wound while the center section of the sheet expands to accommodate increases in pressure or swelling The sheet may include a resealable slit to provide access to the wound as necessary and may be clear to permit observation of the wound through the sheet.  
         [0008]     Specifically, the present invention provides an abdominal and thoracic closure system having a sterilizable flexible sheet which is soft and atraumatic to underlying tissues with a peripheral portion attachable to the skin or fascia of the wound; and a central expandable portion that allows for expansion while providing a continuous covering of the wound by the flexible sheet.  
         [0009]     Thus it is one object of at least one embodiment of the invention to provide an closure system that controls pressure or swelling by expansion without the need for manual adjustment.  
         [0010]     The flexible sheet may be a transparent plastic material.  
         [0011]     Thus it is one object of at least one embodiment of the invention to provide a system that allows visual inspection of the wound.  
         [0012]     The expandable portion may be at least one fold formed in the central portion of the sterilizable flexible sheet.  
         [0013]     Thus it is yet another object of at least one embodiment of the invention to provide a simple method of introducing expandability into materials suitable for wound closure.  
         [0014]     The fold may be along a central fold line where opposite sides of the sterilizable flexible sheet at a first layer approach each other, then fold back upon themselves in a second layer extending away from each other for a predetermined distance, and then fold back again upon themselves in a third layer extending again toward each other to meet at the fold line.  
         [0015]     Thus it is yet another object of at least one embodiment of the invention to provide a fold that does not intrude into the wound or create pressure on the open portions of the wound.  
         [0016]     The three layers may be sealed together at the peripheral portion at ends of the fold line.  
         [0017]     Thus it is another object of at least one embodiment of the invention to provide a folding system that nevertheless preserves closure of the wound against contamination.  
         [0018]     The seal boundary defined by an inner edge of the sealed three layers may be removed inward from an edge of the sterilizable flexible sheet.  
         [0019]     It is a further object of at least one embodiment of the invention to provide an expandable wound closure system that allows trimming the covering to conform to the wound while preserving the sealing of the wound against contamination.  
         [0020]     The seal boundary defined by an inner edge of the sealed three layers may be a line perpendicular to the fold line or an angle opening inward about the fold line.  
         [0021]     Thus it is another object of at least one embodiment of the invention to provide flexible sealing alternatives accommodating tradeoffs between maximum area of expansion and simplicity of manufacture.  
         [0022]     The invention may include an adhesive positioned on the first layer on a side opposite the second and third layers in the peripheral portion.  
         [0023]     Thus it is another object of at least one embodiment of the invention to provide a method of securing the closure system to the edges of the wound prior to or in lieu of staples and or sutures.  
         [0024]     The sterilizable flexible sheet may include indicia indicating that the third layer is to be placed away from the skin.  
         [0025]     It is thus another object of at least one embodiment of the invention to promote correct orientation of the system in emergency conditions.  
         [0026]     The invention may include a resealable seam through the third layer allowing opening of the sterilizable flexible sheet after placement on the skin. The resealable seam includes a sealing means selected from the group consisting of: adhesive, adhesive tape, hook and loop fasteners, and zippers.  
         [0027]     It is thus another object of at least one embodiment of the invention to provide access to the wound without the need to remove the wound covering.  
         [0028]     The invention may include bilateral flexible wings of the same material located on the underside of the first layer, each of which may be tucked under either side of the abdominal or thoracic wall.  
         [0029]     It is thus another object of at least one embodiment of the invention to provide an adhesion preventing barrier between the underlying tissue and the abdominal or thoracic wall.  
         [0030]     These particular objects and advantages may apply to only some embodiments falling within the claims, and thus do not define the scope of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0031]      FIG. 1  is a perspective view of the closure system of the present invention positioned for application above an abdominal wound;  
         [0032]      FIG. 2  is a cross-sectional view of the closure system of  FIG. 1  taken along lines  2 -- 2  when first applied to the wound;  
         [0033]      FIG. 3  is a cross-sectional view similar to that of  FIG. 2  showing expansion of the closure system with increased abdominal pressure;  
         [0034]      FIG. 4  is a top plan view of the closure system of  FIG. 1  showing an area of heat-sealing such as supports an ellipsoidal trimming cut;  
         [0035]      FIG. 5  is a fragmentary perspective view of the closure system of  FIG. 1  cut along line  2 -- 2  showing an optional opening slit at the center of an expansion fold;  
         [0036]      FIG. 6  is a simplified top plan view of the closure system as may be covered by an adhesive surgical drape that does not interfere with the expansion capabilities of the closure system; and  
         [0037]      FIG. 7  is a perspective view of an alternative embodiment of the invention providing flexible lateral wings attached to the underside of an upper layer.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0038]     Referring now to  FIG. 1 , a closure system  10  of the present invention includes a sterile, supple sheet  12  which may, for example, have a rectangular shape and may be formed out of a single sheet of sterilizable biocompatible clear plastic such as polyvinyl chloride (PVC) or other similar materials preferably providing a surface that resists adhesion to tissue.  
         [0039]     The closure system  10  is generally applicable to both abdominal and thoracic wounds, but will be described hereafter in the context of an abdominal wound for clarity. Use of the closure system  10  on thoracic wounds will be understood to those of ordinary skill in the art from this description.  
         [0040]     The sheet  12  is generally sized to amply cover the skin  14  surrounding a typical abdominal wound  16  so that peripheral portions  18  of the sheet may attach directly to the skin  14  around the wound  16  and a center expandable portion  20  may be positioned above the wound  16 . Multiple sizes may be provided with an adult size in one embodiment being 40 cm by 25 cm. The closure system  10  may be provided sealed in a disposable and sterilizable envelope  23  which may be removed prior to application of the sheet  12  to the skin  14  about the wound  16 . A second disposable envelope (not shown) may package envelope  23 , this envelope removed prior to introduction of envelope  23  into the sterile surgical field.  
         [0041]     As an alternate to skin attachment both sides of sheet  12  may be slid through the opening of the wound  16  under the abdominal wall and both sides advanced laterally. The center expandable portion  20  is positioned in the center of the opening of the wound  16 .  
         [0042]     Referring now to  FIG. 2 , the expandable portion of the sheet  12  is provided with expandability via a fold  22  in sheet  12  extending along a fold line  26  separating laterally opposed peripheral portions  18 . The fold  22  allows relatively free expansion of the wound  16 , in contrast to an elastic member, while the peripheral portions  18  relieve stress from the superior and inferior ends of the wound  16 .  
         [0043]     Specifically, the sheet  12  extends inward from the laterally opposed peripheral portions  18  toward the fold line  26  at a first layer  24 . At the fold line  26  these two portions of the sheet  12  folds back upon themselves in a second layer  30  now extending away from the fold line  26  for a predetermined fold distance  32 . When these portions of the sheet  12  at the second layer  30  reach the predetermined fold distance  32  away from the fold line  26 , they fold back again inward upon themselves to form a third layer  34  extending toward each other again to meet at the fold line  26 .  
         [0044]     Referring now also to  FIG. 3 , it will be understood that the fold  22  allows the peripheral portions  18  to separate along a lateral direction perpendicular to the fold line  26  expanding the expandable portion  20 . This expansion allows the relief of increased abdominal pressure and can be detected visually by observing an unfolding of the fold  22  which causes the third layer  30  to move away from the wound  16 .  
         [0045]     Referring still to  FIGS. 2 and 3 , the peripheral portions  18  of the sheet  12  may optionally be reinforced with reinforcement strips  36  adhered to an upper surface or lower surface of the peripheral portions  18  through adhesive or thermal bonding. A pressure sensitive adhesive  38  may be placed on the lower surface of the sheet  12  at the peripheral portions  18  to assist in locating and holding those portions against the skin  14  either independently or in conjunction with sutures or staples. The adhesive  38  may be covered with a protective release liner (not shown) removed prior to use.  
         [0046]     The fold  22  extends upward away from the skin  14  so that the layers in order, moving away from the skin  14 , are the first layer  24 , the second layer  30 , and the third layer  34 .  
         [0047]     Referring now to  FIG. 4 , ends of the fold  22  along fold line  26  may be heat sealed to create a heat seal area  40  in opposed superior-inferior peripheral portions  18  of the sheet  12 . The heat-sealing joins the layers  24 ,  30 , and  34  in the heat seal area  40 . An inner edge  42  of the heat seal area  40  is displaced from the superior-inferior edges of the sheet  12  to allow a trimming cut  44  to be made without breaking the seal established by the seal areas  40 . The inner edge  42  may be an angular edge about trimming cut  44  opening inward to conform generally to an expected ellipsoidal trimming cut  44  or may be straight edge for manufacturing simplicity.  
         [0048]     Referring now to  FIG. 5 , an upper surface of the peripheral portions  18  may be printed with indicia  46  indicating that the proper side of the sheet  12  is upward when the sheet  12  is so applied.  
         [0049]     A center of the third layer  34  may be slit to produce two separable portions  48   a  and  48   b  near the center of the closure system  10 , for example, along the fold line  26  that may be opened for inspection or cleaning of the wound and then closed again and sealed either by a sealing means  50  such as hook and loop fasteners, adhesive tape, or a zipper, or similar zipper-like or closure structure. Sealing tape (not shown) may be provided to further seal zipper or hook and loop sealing means.  
         [0050]     Referring now to  FIG. 6 , the sheet  12  once installed on the patient may be covered by an adhesive surgical drape  52  having a center cutout  54  suitable to expose the expandable portion  20  thereby not to interfere with its expansion. This seal with the adhesive surgical drape  52  can be used to further stabilize the closure system  10 , prevent introduction of contaminants, and create an air tight seal. Alternately, strips of adhesive surgical drape can be cut and fixed to the periphery of the closure system  10  to further stabilize it, prevent introduction of contaminants, and create an air tight seal. Referring now to  FIG. 7 , in an alternative embodiment, the peripheral portions  18  of the sheet  12  may be constructed of an upper layer  56  and a lower layer  58 , the latter attached at an inner edge to the lower surface of the upper layer  56  so that the lower layer  58  extends outward away from the fold line and so that the lower layer  58  may fit between the abdominal wall  51  and the tissue of the abdominal cavity  62  while the upper layer  56  may lie on top of the skin  14  to be attached thereto as described above.  
         [0051]     In an alternative embodiment, not shown, the lower layer  58  may be eliminated and the upper layer  56  placed between the abdominal wall  51  and tissue of the abdominal cavity  62 .  
         [0052]     It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims.