Abstract:
An irrigation dressing is provided including a hollow inflatable tubulardam with a central opening adapted to surround the wound of the individual. A semi-hard resilient clear plastic window is attached to the dam, such that the central opening is completely enclosed on a front surface of the dam. The dressing includes an inner peripheral ridge and an outer peripheral ridge extending beyond a bottom or back body-engaging surface of the dam which facilitates drawing a vacuum. A plurality of connectors are attached to a front planar face surface of the clear plastic window. At least one connector is pivotable about an axis parallel to the front planar surface of the window. A self-sealing plug is disposed inside the dam so that the dam can be inflated to selected pressures using an associated hypodermic needle or the like.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to medical treatment of wounds, and more particularly to an improved wound shield and irrigation dressing for treating wounds to promote the overall healing process and to discourage enteric fistula and wound infections. 
     BACKGROUND OF THE INVENTION 
     Wound shields for treating enteric fistula and wound infections are known. The express purpose of these prior devices is to provide an irrigation dressing for patients as a replacement for the typical gauze type dressings. It is well known that gauze type dressings are not only messy, but result in constant re-opening of the wounds when the dressings are changed, which could cause infections and delay the healing process. Further, dressing changes usually cannot be performed by the patient alone. They are often quite painful to the patient, expensive, and not conducive to providing frequent irrigation of the wound with medical solutions. 
     One known prior art irrigation dressing proposed to alleviate the problems associated with gauze type dressings is shown in expired U.S. Pat. No. 3,026,874. The device taught in that patent provides a wound shield that forms a dam around a wound and includes a clear flexible plastic window or cover for observing the healing process. The dam is fabricated of a continuous loop of foam rubber. To facilitate flushing and air control, several holes are provided at selected locations along the perimeter of the shield. The device is held in place using belts and snap fasteners that are rigidly attached to the wound shield. 
     Although the wound shield described above is preferred over gauze dressings, the foam rubber dam is too rigid for good sealing qualities. Further, the overall wall depth of the device is too shallow to accommodate adequate irrigation solution volumes. Lastly, the dam often comes into contact with the wound thus disrupting the healing process. 
     A modified wound shield or irrigating dressing is shown in FIG.  1 . Wound shield  2  includes a generally oval shaped dam  20  and a window  18  attached over the top of the dam  20 . The shield is secured to a patient by a first belt  4  and a second belt  6 . The ends of the belts  4  and  6  are rigidly connected to window  18  by snap fasteners. Dam  20  includes an irrigation aperture  3  adapted to receive a tube  10  connected on a remote end to a supply of irrigation solution  12 . Dam  20  includes a drying aperture  3  adapted to receive a tube  8  connected on a remote end to a supply of oxygen, and a draining aperture  7  adapted to receive a tube  14  connected to an associated pump  16 . 
     In use of the above device, a flow of irrigation solution constantly irrigates the wound on the patient by a timer control, patient control, or care giver control. Oxygen or air is alternately supplied into the shield to dry the wound, while pump  16  removes the irrigation solution from the enclosed area. The wound is visible through window  18  as it heals without being exposed to contaminants. The dressing can be used for about two weeks before changing is required. 
     The dam of the wound shield described above comprises a hollow, highly flexible tube, which is inflated with air prior to or during use. The desired firmness is obtained by controlling the pressure of air within the dam. 
     Although the wound dressing is modestly successful in treating patients, the device requires a fair amount of readjustment after it is installed on the patient because the dressing twists and bends with movement of the patient. This is primarily due to a lack of flexibility in the wound shield. Further, the device tends to buckle in the middle due to a lack of cross-sectional rigidity in the inflatable dam section. This causes leakage from under the wound shield as well as undesirable contact between the wound and the window. 
     Therefore, it would be desirable to provide an irrigation dressing that is less rigid to prevent separation from the skin of the patient as the patient moves. The irrigation dressing should not be too soft so that it crumples with patient movement. 
     It is also desirable to provide an irrigation dressing that can be readily used with vacuum assist closure (VAC) devices for applying a vacuum to a wound. 
     It is further desirable to provide an irrigation dressing system that can conform to the shape of a moving patient yet retaining its fluid containment and vacuum integrity. 
     SUMMARY OF THE INVENTION 
     In accordance with a preferred embodiment of the invention, a wound shield and irrigation dressing system is provided to be worn on ambulatory patients for protecting and enclosing wounds. The wound shield allows for frequent irrigation of the wound with an irrigation solution and alternate frequent drying of the wound, while also providing for drainage of the irrigation solution and selective application of a vacuum to the wound. 
     The wound shield includes a hollow inflatable tubular dam formed of an inner peripheral surface defining a central opening adapted to surround the wound of the individual, an outer peripheral surface defining the outermost extremity of the dam, a bottom body-engaging surface and a top surface connecting said inner and outer peripheral surfaces to one another. A somewhat stiff clear plastic window is provided having generally flat front and rear planar surfaces. The flat rear planar surface of the window is attached to the top surface of the dam, so that a central cavity opening is defined under the window and surrounded by the oval dam. 
     In a preferred aspect of the invention, the wound shield includes an inner peripheral ridge extending from the inner peripheral surface beyond the bottom body-engaging surface of the dam downwardly away from the window. An outer peripheral ridge is formed on the tubular dam extending from the outer peripheral surface beyond the bottom body-engaging surface of the dam downwardly away from the window. The ridges on the bottom or rear side of the device provide an overall elongate “U-shaped” contact surface for contacting the skin, eliminating the need to apply skin adhesives to the patient, while also sealing in fluids and eliminating vacuum loss. The ridges also play an important part in improving the cross-sectional rigidity of the dam and for preventing fluid leakage. Ridges can also extend from the front or top surface of the dam aiding in the adhesion of the dam to the window, and adding to the overall cross-sectional rigidity of the dam. 
     In another preferred aspect of the invention, the wound shield includes a plurality of connectors attached to the front planar surface of the clear plastic window. Each connector is disposed at different locations outside the central opening of the dam, and each is adapted to be releasably attached to a connecting end of a belt. The connectors are pivotable about an axis parallel to the front planar surface of the window. 
     In yet another preferred aspect of the invention, the subject wound shield includes a resilient self-sealing plug disposed inside the dam. The plug is adapted to receive a hypodermic needle, whereby air can be forced into the dam through the hypodermic needle causing the dam to inflate. The plug is “self healing” and seals itself upon removal of the hypodermic needle, so that the fluid containment integrity of the dam is not compromised. Precise control over the pressure within the dam is thereby enabled. 
     An object of the present invention is to provide an improved wound shield with pivoting belt connectors that allow for patient movement without the need for readjustment of the wound shield. 
     A further object is to provide a wound shield with one or more radial ribs disposed on the perimeter of the dam to prevent fluid leakage from out of the central cavity. It is yet another object of the invention to provide a wound shield with an improved cross-sectional rigidity. 
     A further object is to provide an airtight dam facilitating vacuum assisted closure (VAC). The irrigating dressing is particularly useful with this technique because the wound can be thoroughly cleaned with fluids and thoroughly dried with air using the device before vacuum is applied. The wound can be treated with VAC without irrigation. 
     It is another object of the invention to provide a wound shield having an inflatable dam with an improved inflating device for precise control over the fluid pressure within the dam. 
     Another object of the invention is to provide a wound shield that enables frequent wound cleansing, drying and drainage, while also being easy to use and maintained by care givers and patients. 
     Another object is to make the patient ambulatory while wearing the device. 
     These and other objects will become apparent from the following description of the preferred embodiments taken together with the accompanying drawings and appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention may take physical form in certain parts and arrangements of parts, the preferred embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof, and wherein: 
         FIG. 1  is a perspective view of a prior art wound dressing device; 
         FIG. 2  is a top view of a preferred wound shield and a preferred belt arrangement in accordance with the present invention; 
         FIG. 3  is a cross-sectional view taken along the line A—A of the preferred wound shield shown in  FIG. 2 ; 
         FIG. 4  is a bottom view of the preferred dam of the preferred wound shield shown in  FIG. 2 ; 
         FIG. 5  is a bottom view of an alternative embodiment of the wound shield using cut outs in the window for irrigating, drying, and draining; and, 
         FIG. 6  is a top view of an alternative embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings wherein the showings are for the purpose of illustrating the preferred embodiments of the invention only, and not for purpose of limiting same,  FIGS. 2-4  show a wound shield  30  including a hollow tubular inflatable dam  32 , and a clear plastic window  34  attached to the dam  32 . Dam  32  is formed of an inner peripheral surface or wall  42  which defines and surrounds a central opening  50 . Dam  32  also includes an outer peripheral surface or a wall  44  connected to inner peripheral surface  42  by a rear or bottom body-engaging surface  48  and a front or top surface  46 . 
     Dam  32  is provided with an irrigation aperture  52  extending from outer peripheral surface  44  through inner peripheral surface  42 . Aperture  52  is adapted to receive or otherwise couple with an irrigation tube for providing communication between an irrigation system and central opening  50 . Typically, the irrigation system provides an irrigation solution with medicinal characteristics for continuous or frequent cleansing of the wound. A drying aperture  54  is provided, which is adapted to receive or otherwise couple with a drying tube connected to an associated air supply. Drying aperture  54  provides communication between the air supply and central opening  50  for continuous or selective intermittent drying of the wound after irrigation. The drying aperture is also useful for connection to an associated source of vacuum (not shown) for use with VAC devices to apply a vacuum to the wound. A drainage aperture  56  is provided, preferably on a side of the dam opposite from the irrigation and drying apertures as shown. The drainage aperture is adapted to receive or otherwise couple with a drainage tube. The drainage tube could be connected to a pump, a collecting device, or a like device, to facilitate the removal of the irrigation solution, and dead skin and blood discharged from the wound. Both apertures  52  and  56  extend through the dam  32  from outer peripheral surface  44  through inner peripheral surface  42 . These apertures can be plugged using suitable stoppers or the like when used as a VAC, when the patient is ambulatory, or as desired. It is to be appreciated that any of the apertures can be adapted for connection with an associated source of vacuum. 
     Dam  32  is preferably manufactured using a rotational casting or a rotational molding such as slush molding. The mold is typically made of aluminum but could be made of a variety of other metals. Dam  32  is formed from a soft liquid plastic, preferably vinyl, and the apertures are formed by extending a core pin through the mold, and removing the core pin after the liquid plastic cures. 
     Dam  32  further includes a soft self-sealing plug  40  preferably molded into the outer wall  44 . Self-sealing plug  40  is adapted to receive a hypodermic needle used to inflate the dam  32  with air. The needle is inserted through the self-sealing plug  40  and the bulb is compressed to force air into the dam until the desired firmness of the dam  32  is obtained. The needle can be withdrawn at any time from the self-sealing plug  40  without any leakage of the air after removal. The self-sealing plug also allows for addition or removal of air at any time. Self-sealing plug  40  is preferably made of nitriale rubber. 
     Window  34  is made of a semi-hard clear plastic vinyl and has a generally flat planar bottom surface  33  and a generally flat top planar surface  35 . In the embodiment illustrated, the window has an overall generally rectangular shape. Preferably, bottom planar surface  33  is attached to front surface  46  of the dam  32  using ultra-violet curable adhesive. However, various other types of adhesives could be used. Window  34  completely encloses central opening  50  of the dam  32  so that central opening  50  can remain airtight when the wound shield  30  is placed on the body of the patient, except for apertures  52 ,  54 , and  56 . It is preferred that window  34  encompass outer peripheral surface  44  of the dam  32  to increase the rigidity of the wound shield  30 . 
     A pair of spaced apart connector assemblies  64  are disposed on top planar surface  35  of window  34  at opposite sides of the window. Connector assemblies  64  include a set of spaced apart co-axial tubes  66  holding a rod  68  that is connected to a set of eyelets  70 . Tubes  66  are preferably made of plastic and could be bonded to top planar surface  35  of the window  34  or could be formed during the molding of window. Rods  68  and eyelets  70  are placed in tubes  66  prior to bonding or molding. Rod  68  and eyelet  70  are pivotable about an axis parallel to top planar surface  35 , so that movement or twisting of the patient does not cause wound shield  30  to move from its position on the body of the patient. Further, connector assemblies are placed at a location outside central opening  50  to ensure that even pressure is applied to the entire perimeter of dam  32  when wound shield  30  is on the body of a patient. Rods  60  and eyelets  70  are preferably made of metal, but could be made of plastic or the like. The rods  68  extend completely across the face of the would shield  30  and in that way help prevent the shield from buckling in the middle during use such as along the line defined by section A—A in FIG.  2 . 
     A pair of belts  36  and  38  are provided for holding wound shield  30  at a fixed location on the patient, so that central area  50  surrounds the wound. Belts  36  and  38  are preferably made of an elastic material, such as latex or neoprene foam, and are preferably non-absorbent and easy to clean. Each belt includes a first and a second connecting end  58 . Each connecting end  58  includes a connecting portion  60  attached to the belt, and a hook portion  62  adapted to engage eyelet  70 . It should be appreciated that in some circumstances, the wound shield may only need one belt because of the size or location of the wound. Further, the belt could be fixed at one end to a fixed connector on the wound shield, and be pivotable at the other end. It also should be appreciated that the releasable engagement of the belt and the connector assembly could employ connector types other than the preferred eye and hook arrangement. 
     With particular reference now to  FIG. 3 , dam  32  includes a ridge  72  extending angularly from inner peripheral surface  42  beyond and away from the bottom body-engaging surface  48 . Dam  32  also includes a ridge  74  extending angularly from outer peripheral surface  44  beyond and away from the bottom body-engaging surface  48 . Ridges  72  and  74  cooperate in holding wound shield  30  in a fixed position on the patient&#39;s body, even during movement and twisting of the patient. Further, ridges  72  and  74  seal central opening  50  and prevent any fluids or vacuum from escaping, and prevent contaminants from entering central area  50 . Ridges  72  and  74  also alleviate the need to apply skin adhesives to the skin of the patient prior to applying the front body-engaging surface of the wound shield, while adding substantially to the cross-sectional rigidity of the dam  32 . 
     With continued reference to  FIG. 3 , dam  32  preferably also includes a ridge  76  extending angularly from inner peripheral surface  42  beyond and away from top surface  46  and a ridge  78  extending angularly from outer peripheral surface  44  beyond and away from top surface  46 . Ridges  76  and  78  aid in the adhesion process of front surface  46  to the back surface  33  of window  34 . Additionally, ridges  76  and  78  increase the cross-sectional rigidity characteristic of dam  32 , which helps prevent the center of the wound shield  30  from buckling after securing wound shield  30  on the body of a patient. 
     It should be appreciated that in some cases, such as in stubborn wounds, more pressure is necessary for irrigation of the wound. It also should be appreciated that it is not always necessary to place irrigation aperture, drying aperture, and drainage aperture through the dam. For example,  FIG. 5  shows a wound shield  77  having a dam  79  attached to a window  81 . A first hole  75  is cut out of window  81  and covered over by a piece of adhesive tape  80  or plug. A second hole  82  is cut out of window  81  and covered by a piece of adhesive tape  84  or plug. The holes  75 ,  82  are adapted to receive the tip of an asepto syringe. Adhesive tape  80  or plug can be removed and irrigation solution can be communicated to the wound through hole  75  via large syringe, or the like. Further, an air source could be used to communicate air to the wound through hole  75  for drying the wound. Adhesive tape  84  or plug can be removed to provide drainage of irrigation solution, dead skin, and blood from central area  50 . After cleansing, drying, and drainage, tape  80  and  84  or plug can be placed back over holes  75  and  82 , respectively, protecting the wound from outside dirt or bacteria. 
     It should be noted that the shape of the wound shield could take on many forms, and the connector assemblies could be disposed on the window in a variety of different orientations. For example,  FIG. 6  shows a wound shield  30 ′ having an overall smaller size than the shield  30  shown in  FIGS. 2-4 . Only a single belt  36 ′ is needed to receive the shield  30 ′ to a patient. This type of wound shield could be useful for a wound near the groin area of an individual, such as one that would occur in a hernia operation or catheterization procedure. The wound shield  30 ′ is formed and functions substantially identical to the shield  30  described above. Like parts are indicated in  FIG. 6  with a primed (′) suffix. 
     The foregoing descriptions are specific embodiments of the present invention. It should be appreciated that these embodiments are described for purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.