Abstract:
Devices and methods are disclosed for achieving hemostasis in traumatized patients. The devices utilize fluid impermeable outer surfaces and distributed pressure to achieve tamponade and hemostasis, primarily by exertion of pressure. The devices are capable of serving as carriers for throabogenic or antipathogenic agents. Peripheral haemostatic packing devices include optional adhesive hemostatic barriers to cover the entire wound area over the hemostatic pack. The hemostatic packing devices may be placed and removed by open surgery or laparoscopic access without generating excessive re-bleeding, and may further comprise antimicrobial or thrombogenic regions.

Description:
The present application claims priority benefit under 35 USC § 119(e) from U.S. Provisional Application No. 60/354,429 filed Feb. 4, 2002, entitled “METHOD AND APPARATUS FOR IMPROVED HEMOSTASIS AND DAMAGE CONTROL OPERATIONS” and U.S. Provisional Application No. 60/424,038 filed Nov. 5, 2002, entitled METHOD AND APPARATUS FOR EMERGENCY VESSEL ANASTOMOSES, both of which are herein incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The field of this invention is wound care during trauma surgery, general surgery, combat medicine, and emergency medical services. 
     BACKGROUND OF THE INVENTION 
     As recently as the early 1990s, surgical operations for trauma were directed at the anatomic repair of all injuries at time of the initial operation. It was observed during these exercises that many patients became hypothermic, acidotic, and coagulopathic. Patients showing these three signs often died. Death often occurred in the operating room due to exsanguinations, or postoperatively, due to the complications of prolonged shock and massive transfusion to replace blood lost as a result of the trauma. 
     One of the most notable developments in the recent evolution of surgery has been the introduction of the concept of staged laparotomy to overcome the deficiencies of the repair all-at-once approach. This new strategy of staged laparotomy, employing new tactics that have been termed damage control, is now used in 10% to 20% of all trauma laparotomies. 
     Ever since the advent of abdominal surgery, surgeons have relied on the same thinly woven cotton gauze packing pads that are currently in favor. These gauze pads are called laparotomy pads or Mickulitz pads. These pads were designed for use as sponges but not for use as hemostatic tampons. Nonetheless, since World War I, surgeons faced with severe bleeding have relied on packing patients with these sterilizable gauze sponges in an effort to control bleeding. Since World War II, it has been known that abdominal packing using these pads has been associated with abdominal sepsis and re-bleeding after pad removal. Despite these limitations, even today, they are the mainstay of damage control hemostasis. 
     The specific issues with the gauze pads are that they are porous and allow the free passage of blood through the mesh. Other unfavorable characteristics include the lack of intrinsic coagulation inducing properties. The pads are easily saturated but these pads do not stick to one another. The pads are capable of promoting infection because they serve as a nidus for bacteria in a contaminated field. They have no intrinsic antiseptic or antimicrobial action. These pads are unsuitable for packing solid viscera because they stick to the visceral wound tissue and cause re-bleeding upon removal. Although generally recognized as sub-optimal, the gauze pads have the advantages of being cheap, familiar and ubiquitous. For these later reasons, they continue to remain the mainstay of damage control hemostasis. Among the opportunities for new technologies and instruments to support the process of damage control, the first requirement is an improvement in the surgical pack. 
     Other current pads for hemostasis include gel-foam, Surgicel, and fibrin sponges. These devices are all liquid permeable and require blood coagulation to occur before impermeability and hemostasis are achieved. In addition, the fibrin sponges are very rigid and will not conform to a wound while in the dry state. Typical examples of the prior art in hemostatic packing systems include U.S. Pat. No. 5,643,596 to Pruss et al., U.S. Pat. No. 5,763,411 to Edwardson et al., U.S. Pat. No. 5,800,372 to Bell et al., U.S. Pat. No. 6,054,122 to MacPhee et al., and U.S. Pat. No. 6,056,970 to Greenawalt et al. These patents, all of which are included herein by reference, disclose permeable hemostatic packing and dressings with topical hemostatic coatings. These devices all serve the purpose of stopping bleeding in underlying vessels with an occlusive backing but the backing is still permeable to blood leakage. The lack of impermeability in these prior art patents is not recognized as an issue. 
     While hemostatic packing devices are well known in the art, the utility of said packing devices is limited by their propensity to harbor pathogens and their propensity to create re-bleeding by adherence to healing surfaces. 
     New devices, procedures and methods are needed to support the strategy of damage control in patients who have experienced massive bodily injury. Such devices and procedures are particularly important in the emergency, military, and trauma care setting. These new devices rely on the principles of impermeability to blood passage, limited nidus formation for bacteria, the ability to carry pro-thrombogenic material, and the lack of intrinsic thrombogenicity except by providing a physical barrier or pressure source. 
     SUMMARY OF THE INVENTION 
     The devices and methods described below provide for improved hemostatic packing in trauma care. The devices comprise impermeable barrier packs with various features provided to improved hemostasis, improved packing and placement of the packs, and easier removal of the pack after hemostasis is achieved. Other features of the pack include foldability and moldability to the anatomical surface. The exterior surface of the pack is not intrinsically thrombogenic but is capable of serving as a carrier for thrombogenic substances. Certain regions of the exterior surface of the pack may optionally comprise thrombogenic properties. The pack may be made with a plurality of surfaces, each with distinct characteristics. An exemplary version of the pack has a thin layer of polyethylene or polypropylene, which is impermeable to liquids, as its entire outer surface. A key advantage of the present invention, in its wet or dry state, is moldability, flexibility and shapability to the anatomical contacting surface, including the ability to pack wounds in solid viscera. The pack is able to distribute pressure within the wound to generate pressure tamponade. The pack is capable of generating pressure tamponade without regions of sharp or high stress such as would be generated by a rigid packing system. This improvement over certain very hard packing devices allows for better fit to the anatomy and the immediate formation of an impermeable barrier without the need to wait for blood coagulation to occur to form the hemostatic barrier. The hemostatic pack of the present invention is placed via open surgery or through laparoscopic instrumentation. The laparoscopic embodiment includes the capability of reversibly or irreversibly achieving a size and mass change in the device once it is placed within the patient. 
     The present invention distinguishes over the cited prior art because it requires no thrombogenic coatings, although it is capable of trapping and carrying such pro-thrombogenic coatings on its surface. The outer surface of the haemostatic packing sponge serves as a carrier by incorporating indents or villi to physically hold the pharmacological, thrombogenic or antibacterial coatings. Since the surface is impermeable to liquids, the arrest of hemorrhage is immediate and does not require thrombosis to occur. When the packing device of the present invention is removed from the patient, re-bleeding does not occur because there is no penetration of the wound tissues or clot into the interstices of the pack. An additional advantage of the impermeable pack is a resistance to bacteria and other pathogenic penetration. 
     In another embodiment of the invention, the pack comprises raised ridges or dams on its surface. These ridges or dams are comprised of soft conformable materials that form an edge seal to prevent the escape of blood from a wound. The pack optionally comprises additional regions or borders of enhanced blood clotting or thrombogenesis to assist with the hemostatic properties of the device. 
     In yet another embodiment of the present invention, the hemostatic pack comprises adhesives, fasteners, or the like to allow the packs to adhere to each other, thus forming a syncytium, or contiguous barrier comprised of more than one component, to prevent blood from escaping from a wound. 
     For purposes of summarizing the invention, certain aspects, advantages and novel features of the invention are described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a two-sided hemostatic pack comprising a sheet of material that is impermeable to liquid on one side and the other side is a permeable fabric affixed to the impermeable barrier; 
         FIG. 1B  illustrates a cross-sectional view of the two-sided haemostatic pack; 
         FIG. 1C  illustrates the two-sided hemostatic packing device folded with the impermeable surface facing outward toward the wound surface; 
         FIG. 1D  illustrates the two-sided hemostatic pack rolled with the impermeable side out; 
         FIG. 2  illustrates a hemostatic packing device comprising a closed-cell foam that is impermeable on both sides; 
         FIG. 3  illustrates a hemostatic packing device comprising an outer surface that is impermeable on both sides where the upper surface further comprises indentations capable of carrying exogenous thrombogenic substances; 
         FIG. 4  illustrates a hemostatic packing device comprising a polygonal deformable solid with an impermeable outer surface; 
         FIG. 5A  illustrates an inflatable hemostatic packing device; 
         FIG. 5B  illustrates one embodiment of the inflatable hemostatic packing device in its deflated or partially deflated state; 
         FIG. 6  illustrates a hemostatic packing device being introduced into a patient through a laparoscopic instrument; 
         FIG. 7  illustrates a hemostatic packing device comprising an adhesive on at least a portion of the outer impermeable surface of said hemostatic packing device; 
         FIG. 8  illustrates a hemostatic packing device comprising a packing material with an impermeable outer surface affixed to an adhesive impermeable drape; 
         FIG. 9A  illustrates a wound of the liver; 
         FIG. 9B  illustrates the wound of the liver being treated by application of internal tamponade of hemorrhage with the impermeable hemostatic packing device used in a peri-hepatic location; 
         FIG. 10A  illustrates a wound of an exemplary extremity, the thigh, with femoral artery transection; 
         FIG. 10B  illustrates the wound to the thigh being treated by application of an impermeable hemostatic packing device with the adhesive impermeable drape; 
         FIG. 11  illustrates a wound dressing or bandage comprising a blood dam, for treating a wound to the arm or the leg. 
         FIG. 12  illustrates a wound dressing or bandage for treating a wound to the arm or the leg comprising a series of blood dams. 
         FIG. 13  illustrates a wound dressing or bandage for treating a wound to the arm or the leg comprising a blood dam with a communicating valve; 
         FIG. 14A  illustrates a lateral sectional view of two internal hemostatic packs for solid organs, viscera, and the like; 
         FIG. 14B  illustrates a lateral sectional view of two internal hemostatic packs that have been joined together to form a syncytium wherein the barrier regions or dams render the adherent region impermeable to fluids such as blood. 
         FIG. 15  illustrates an oblique view of a preferred wound dressing or bandage for treating a wound to a body part comprising a strap, a blood dam, and a pillow pack. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1A  illustrates a diagram of a two-sided hemostatic packing device  10  of the present invention. The two-sided packing device  10  comprises a blood permeable layer or substrate  12  and a fluid impermeable covering  14 . The fluid impermeable sheet  14  further comprises an optional adhesive layer  16 , and a plurality of optional indentations  18  on the exterior surface. The fluid impermeable covering  14  or the substrate  12  may optionally comprise a plurality of radiopaque markers  20 . The hemostatic packing device  10  is a flat sheet that is flexible and deformable. The substrate  12  is a flat sheet configuration and is integral to or affixed to the fluid impermeable covering  14 . The fluid impermeable covering  14  optionally comprises a plurality of indentations  18 . The radiopaque markers  20  may be wire form, dots or patches of barium-impregnated fabrics. 
     The substrate  12  is soft in its wet or dry state and may be bent, molded or deformed to maximize surface contact and force distribution on injured tissue. The substrate  12  is fabricated from cotton gauze, open or closed cell foam, sponge, fluids, particulates and the like, or from inflatable or packable masses of particulates. The foam configuration of the substrate  12  may be fabricated from materials such as polypropylene, polyvinyl chloride, polyurethane, polyethylene, silicone rubber, poly methyl methacrylate, polyvinyl alcohol and the like. The particulates of the inflatable embodiment of substrate  12  may be beads of collagen, PTFE, silica and the like. The fluid impermeable covering  14  is fabricated from materials such as polypropylene, polyvinyl chloride, polyurethane, polyethylene, silicone rubber, poly methyl methacrylate, polyvinyl alcohol, Tyvsk® and the like. The fluid impermeable covering  14  may also be fabricated from materials such as paper or cloth that is then coated or sprayed with impermeable materials such as polyethylene, polypropylene and the like. The use of rip-stop fabrics will help prevent tearing of the fluid impermeable covering  14 . 
     The hemostatic packing device  10  is fabricated in a variety of sizes and thicknesses. The thickness varies from 0.1 mm to 50 mm. The length and width each may vary from 5 mm to 500 mm. The geometry is generally rectangular but may have triangular, circular, or polygonal configurations. The corners may be square or rounded. 
     The radiopaque markers  20  are fabricated from a group of materials including but not limited to barium impregnated fabrics or polymers, metal wires, and metal solids. Typical metals used for radiopacity include tantalum, platinum, gold, and the like. 
     The hemostatic packing device  10  is packaged in a sealed, sterile barrier package and is sterilized using standard techniques such as steam, cobalt radiation, ethylene oxide, electron beam and the like. 
     Referring to  FIG. 1B , the hemostatic packing device  10  is shown from the side. The substrate  12 , the fluid impermeable covering  14 , and the adhesive layer  16  are clearly visible in this view. 
     The component illustrated in  FIGS. 1A and 1C  are folded or rolled to form the desired hemostatic packs, which are illustrated in  FIGS. 1C and 1D .  FIG. 1C  illustrates one embodiment of the hemostatic packing device  10  that is folded with the fluid impermeable covering  14  facing outward in preparation for use.  FIG. 1D  illustrates another embodiment of the hemostatic packing device  10  that is rolled with the fluid impermeable covering  14  facing outward in preparation for use. Prior to use (either in manufacture or in the field, immediately before packing a wound), the component sheet is folded or rolled. If folded or rolled in manufacture, the device will be packaged and shipped in its final form. If manufactured in the field, the doctor or paramedic will make the device from the component sheets, folding or rolling the sheets to make packs of suitable size and shape, as dictated by the shape of the wound presented. 
       FIG. 2  illustrates another embodiment of the haemostatic packing device  10  where the substrate  12  and the fluid impermeable covering  14  are fabricated from the same material. In this embodiment, the hemostatic packing device  10  is fabricated from closed-cell foam, where the substrate is the foam, and the outer layer is the typically impermeable skin of the foam. The foam material allows for a resilient, deformable substrate while maintaining the fluid impermeable covering  14  that is impermeable to fluid penetration since it is a closed cell structure. 
       FIG. 3  illustrates the hemostatic packing device  10  where the upper side of the fluid impermeable covering  14  comprises indentations  18 , that may be in the form of dimpling or waffling of varying depth that are useful to deliver thrombogenic, pharmaceutical or antibacterial agents. The indentations  18  are formed using molds wherein the outer surface of the fluid impermeable covering  14  of the closed-cell substrate  12  is formed against the mold. In another embodiment, the indents  18  are formed by impressing the fluid impermeable outer sheet with a mold or other forming device. In yet another embodiment, the the fluid impermeable covering  14  comprises projections, or villi, that serve to trap and carry the pharmaceutical, antibacterial or thrombogenic agents. The projections or indents may be macroscopic or microscopic. 
       FIG. 4  illustrates another embodiment of the haemostatic packing device  10  wherein the substrate  12  forms a polygonal solid. The polygonal solids include shapes such as brick or rectangular solid, waffle, pyramid, sheet, and oval. The polygonal solids also include extruded shapes such as cylinders, or extended lengths of cross-sections such as rectangular, oval, circular, trapezoidal, triangular, etc. The lengths of these devices range from 5 mm to 1000 mm. The width dimensions of these devices range from 1 mm to 200 mm. For a typical use, such as v-shaped wounds such as laceration in the leg, the device can be provided in dimensions of about three to eight inches long (7.5 to 20 cm), with sides of about 0.5 to 2 inches (1 to 5 cm). At least part of the fluid impermeable covering  14  of the hemostatic packing device  10  comprises a fluid impermeable barrier. This fluid impermeable covering  14  may be smooth, indented, or covered by villi, or projections. The substrate  12  is fabricated from materials that allow for deformation in the dry or wet state. These materials include cotton batting, polymeric foams of varying densities, sand, polymer beads, oils including silicone oils, water, and the like. 
     Referring to  FIGS. 1A ,  1 B,  1 C,  1 D,  2 ,  3 , and  4 , the hemostatic packing device  10 , in another embodiment, comprises a fluid fluid impermeable covering  14  that is fabricated from resorbable materials. The substrate  12  may be removed and the fluid impermeable covering  14  left behind to complete healing. The  14  is fabricated from resorbable materials such as polyglycolic acid (PGPL), polylactic acid (PLA) and the like. The fluid impermeable covering  14  has a complex surface that comprises indentations or villi  18 . 
       FIG. 5A  illustrates yet another embodiment of the hemostatic, packing device  10  wherein the device may have fluid reversibly or irreversibly introduced to provide for size adjustment. The fluid impermeable covering  14  is, as in the previous figures, fluid impermeable. It is formed into a closed bladder with a shape adapted to fill typically voids in damaged organs and body parts. An access port  22  provides for fluid communication from the exterior of the packing device to the interior of the device, for introduction of substrate materials or materials to fill the substrate  12  within the outer layer. The packs may also be filled with water or oil, or by gas such as air, carbon dioxide, nitrogen and the like. In this embodiment, the substrate  12  is bladder formed from a fluid impermeable membrane that is filled with material to achieve the desired volume. The substrate  12  membrane is fabricated either from elastic materials such as silastic or polyurethane, or it is an inelastic bag with folds that allow for size increase. The outer surface of the substrate  12  preferably is not adhered in all places to the fluid impermeable covering  14  of said device  10  and optionally a lubricating layer  24  is placed between the two structures. The fluid impermeable covering  14  of said device  10  is fabricated from either elastic materials such as polyurethane or silicone rubber, or it is an inelastic material such as polyethylene terephthalate, polyimide, polypropylene or polyethylene or a copolymer including one of these materials. The fluid impermeable covering  14  of the hemostatic packing device  10  may be smooth, indented or include villi. The villi or indents may be macroscopic and have size ranges from 0.1 mm to 10 mm. The villi or indents may also be microscopic and difficult to see with the unaided eye. Such sizes are less than 0.1 mm. 
     Referring to  FIG. 5A , the hemostatic packing device  10  comprises a hydrogel material that is placed into a wound and expands upon absorption of fluids from the patient to compress the wound. In this embodiment, the substrate  12  is fabricated from hydrophilic hydrogels such as those described by Park et al. and are incorporated herein by reference. Hydrogels are made from materials such as, but not limited to, carboxymethyl cellulose, cross-linked sodium starch glycolate, and cross-linked polyvinylpyrrolidone and the like. The substrate  12  can also be fabricated from a water-absorbable sponge that expands once it becomes wet. The water-absorbable sponge may be fabricated from materials such as, but not limited to polyvinyl alcohol, polymethyl cellulose, and the like. In this embodiment, the fluid impermeable covering  14  is provided with an opening to allow for fluid penetration into the substrate  12  to allow the expansion to occur. This opening may be the access port  22  and the fluid to expand the hydrogel or sponge may be injected through the access port  22 . Alternatively, in the case of the hydrogel, the substrate  12  and the fluid impermeable covering  14  may be of the same hydrogel material. Hydrogels generally absorb water but do not adhere to biological surfaces. The hemostatic packing device  10  fabricated from hydrogel would be small enough in its dry state to be introduced through a laparoscopic access port and expand due to water absorption once placed within the body. 
     The devices of  FIGS. 5A and 5B  may be filled just prior to placement in the patient. The degree to which they are filled may be determined by the doctor or paramedic, depending on nature of the wound, including its size and organ which is wounded. The packs may also be filled or deflated after placement, whether to account for leakage or to adjust the size to account for changes in physiology or to make room for surgical devices. Such intraoperative filling of the bladder may be accomplished in an intraoperative time frame encompassing initial encounter and diagnosis of the patient, field treatment, emergency treatment and delayed treatment. The devices may also be placed peri-operatively for a short period of recovery after surgery performed to repair the trauma. 
       FIG. 6  illustrates the hemostatic packing device  10  being introduced into a wound  42  in a liver  40  through a laparoscopic instrument  30 . The laparoscopic instrument  30  is an axially elongate hollow device that provides porthole access to the internal organs of a patient. 
       FIG. 7  illustrates the hemostatic packing device  10  comprising an adhesive strip  28  on one side. The adhesive strip  28  is used to permit attachment of the hemostatic packing device  10  to other similar devices so as to create an impermeable syncytium or impermeable contiguous mass. The adhesive strip may also comprise an optional peel away cover that protects the adhesive strip  28  prior to use. The peel away cover is fabricated, preferably, from the same materials use to fabricate the fluid impermeable covering  14  of the hemostatic packing device  10 . The adhesive strip is optionally fabricated from loop and hook fasteners such as Velcro® or even self-adhesive materials such as Coban®, marketed by 3M. 
       FIG. 8  illustrates another embodiment of the hemostatic packing device  10  further comprising a fluid impermeable drape  32  affixed to the packing device  10 . The fluid impermeable drape  32  is, preferably adhered to the hemostatic packing device  10 . The drape  32  comprises an adhesive layer  36  and a backing layer  38 . The backing  38  is, preferably, fabricated from non-elastomeric materials such as, but not limited to, polyethylene, polypropylene, and the like. It is preferable that the drape  32  does not stretch once applied. The adhesive layer  36  is on the same side of the drape  32  to which the hemostatic packing device  10  is affixed. The hemostatic packing device  10  further optionally comprises a series of straps  34  to assist with fixation of the device to the patient. The straps  34  are fastened with standard buckles, Velcro or the like. This embodiment of the device  10  is useful for treatment of wounds to the periphery and especially those wounds that involve vascular injury. Such periphery includes the thigh, knee, lower leg, arm, shoulder, and forearm. 
       FIG. 9A  illustrates the wound  42  to the liver  40 . The liver  40  represents an exemplary case of parenchymal tissue that is friable and becomes severely damaged during an abdominal injury. 
       FIG. 9B  illustrates the wound  42  to the liver  40  being treated by application of intra-parenchemal packing using one or more hemostatic packing devices  10 . In this embodiment, two hemostatic packing devices  10  are used to provide hemostasis for the wound  42 . The hemostatic packing devices  10  are applied manually via open surgery or laparoscopically, depending on the nature of the wound and the surgical technique, as determined by the doctor or paramedic placing the packs. 
       FIG. 10A  illustrates a wound  44  to the periphery and more specifically, the thigh  46 . The wound  44  has caused femoral artery  48  to become transected. 
       FIG. 10B  illustrates the wound  44  to the thigh  46  being treated by application of the impermeable hemostatic packing device  10  with the adhesive impermeable drape  32  and straps  34 . 
     In yet another embodiment, a wound closure is fabricated from a material that has skin and wound contact surfaces that are impermeable to water, blood and tissue penetration. Preferably, these wound closure devices are fabricated from sheets of materials such as, but not limited to, polyurethane, polypropylene, polyethylene, silicone elastomer, and the like. The skin contact surface is a biocompatible adhesive and is further impregnated with anti-microbial agents such as, but not limited to, iodine, betadine and the like. The bandage or wound closure device is large enough to completely surround the wound and seal in the wound so that blood cannot escape. The bandage, optionally, has additional straps that fully surround the body or appendage and seal with Velcro, buckles, clamps or the like. The bandage or wound closure device seals the wound against the full systolic blood pressure and, thus tamponade any bleeding that occurs from damaged vessels other than the one repaired with the shunt  10 . The bandage comprises an adhesive region that sticks to the skin, even if the skin is wet or bloody. The bandage is optionally maintained in place using straps that wrap around the body or appendage and secure the bandage in place with adequate pressure to generate pressure tamponade of the wound. 
     The preferred wound closure is a large piece of Ioban®, a trademark and product of 3M Corporation, the non-adhesive side of which is adhered to a piece of woven gauze or mesh to provide adequate structure to the weak membrane of the Ioban®. The Ioban has adhesive and anti-microbial properties preferred for this application. A strap extending from opposing ends of the bandage and terminated with a loop and hook fastener such as Velcro® or 3M Coban®, which is self-adherent, assists in maintaining pressure against the wound and proving full tamponade of the hemorrhage. In yet a further embodiment, the central part of the skin contact region comprises a malleable or conformable pad, preferably adhered to the wound closure device, which helps to exert hemostatic force on the wound. The conformable pad evenly distributes the forces throughout the wound so that no areas receive either too high a pressure, or too low a pressure, such as would permit further bleeding. The conformable central pad may be a block of foam covered by the aforementioned impermeable layer, or it may be an impermeable membrane, preferably elastomeric, filled with liquid such as saline or even a particulate material such as, but not limited to, sand, flour, sugar, silicone oil, or the like. In a preferred embodiment, the material used to form the fluid-tight membrane is liquid impermeable but gas permeable. Materials suitable for such permeability requirements include expanded polytetrafluoroethylene (ePTFE) and the like. 
       FIG. 11  illustrates a wound dressing or bandage comprising a blood dam, for treating a wound to the arm or the leg. The hemostatic packing device  10  is in the form of a wound dressing or bandage  50 . The wound dressing or bandage  50  further comprises a gauze or absorbent region  52 . The gauze or absorbent region  52  may have material bulked up or rolled up to aid in the application of pressure to cause pressure tamponade of the wound or perforation to the body. The gauze or absorbent region  52  may alternatively be a fluid pouch, which may be inflated or deflated to apply the required pressure tamponade to the wound area. The gauze or absorbent region  52  is further comprised of a peripheral gasket  54  or a plurality of gaskets  54  running in a honeycomb, rectangular or other appropriate pattern throughout and within the gauze or absorbent region  52  of the bandage  50 . The gasket  54  aids in hemodynamic control and is made out of fluid impermeable materials, such as, but not limited to, silicone, C-flex, hydrogels, silicone oil-filled membrane, polyurethane closed-cell foam, and the like. The typical width of the gasket  54  material will be ⅛ to ¼ inch, but the gasket may be made larger for wounds that require greater hemodynamic stabilization which can be achieved by the damming function of a larger gasket. The gasket  54  is wide enough to distribute pressure over the skin area so as not to cause petcheciae, bruising or tissue damage while applying enough pressure to seal against systemic arterial pressure, typically 100 to 300 mm Hg. The dam or gasket  54  generally presses gently into the tissue surrounding the wound to ensure a strong resistance to hemorrhage or leakage of blood beyond the dam. Affixed or integral to the gauze or absorbent region  52  is a plurality of fluid impermeable straps  58  that will wrap around the extremity or wound area. The straps  58  may contain an adhesive layer  36  or may be of material suitable for stretch wrapping. Optionally, the straps  58  may comprise an adhesive layer  36  and a backing layer  38 . The backing  38  is, preferably, fabricated from non-elastoineric materials such as, but not limited to, polyethylene, polypropylene, Tyvek®, polytetrafluoroethylene, polyester, and the like. Another option for the straps  58  could be adhesive straps  58  made from materials such as, but not limited to, those manufactured by 3M, Inc., under the trade name of Ioban. This material would be suitable and desirable for use as the straps  58  due to its chemical composition and inherent antiseptic properties. In addition, the wrapping material may also have buckles or Velcro  62  or another means of securing or attaching the bandage in place on the patient. Self-adhesive materials such as, but not limited to, those manufactured by 3M, Inc., under the trade name of Coban® are suitable for use as the binding system for the straps  58 . The straps  58  may also be fluid impermeable, so as to aid in the wound containment. The bandage or wound dressing  50  also has a free end or side  60 . Ideally, the wound dressing or bandage  50  would be packaged with a protective, removable layer over the gauze or absorbent region  52  and quite possibly over the entire surface applied to the patient. 
       FIG. 12  illustrates another embodiment device illustrated in FIG.  11 . The hemostatic packing device  10  is in the form of a wound dressing or bandage  50 , as shown in FIG.  11 . The wound dressing or bandage  50  further comprises a gauze or absorbent region  52 . The gauze or absorbent region  52  is further comprised of a plurality of dams or gaskets  54  running or weaving in a honeycomb, rectangular, diamond, or other appropriate pattern throughout and within the gauze or absorbent region  52  of the bandage  50 . The gasket  54  aids in hemodynamic control and is made out of fluid impermeable materials, such as, but not limited to, silicone, C-flex, hydrogels, silicone oil-filled membrane, polyurethane closed-cell foam, and the like. The typical width of the gasket  54  material will be ⅛ to ¼ inch (again, the gasket may be made larger for wounds that require greater hemodynamic stabilization which can be achieved by the damming function of a larger gasket). The gasket  54  is wide enough to distribute pressure over the skin area so as not to cause petcheciae, bruising or tissue damage but enough pressure to seal against systemic arterial pressure, typically 100 to 300 mm Hg. 
       FIG. 13  illustrates a wound dressing with a blood dam as shown in  FIGS. 11 and 12 , modified with the addition of a valve communication from the intended body contacting surface to the intended exterior or superficial side of the wound dressing. The hemostatic packing device  10  is in the form of a wound dressing or bandage  50 , similar to those shown in  FIG. 11  of  12 . The wound dressing or bandage  50  further comprises a gauze or absorbent region  52  and a valve  56 . The valve  56 , which resides within the gasket  54 , may be used to remove fluids or add agents to assist in the coagulation or wound containment. The valve  56  may be, but is not limited to, a duck bill type of valve, or the like. 
       FIG. 14A  illustrates a system of hemostatic packs which can be releasably attached together just prior to use to form a hemostatic structure as desired by the doctor treating a patient. Hemostatic packs  100  and  102  both comprise solid shapes (such as cylinders, prisms, pyramids, cones, spheres, polyhedrons and extended lengths with other cross-sections such as rectangular, oval, circular, trapezoidal, triangular, etc.), each with an impermeable outer layer  115  and a soft-conformable filler region  113 . The left hand internal pack  100  further comprises a female adhesive region  104  further comprising an adhesive material  106  and a plurality of adhesive material gaps  108 . The right hand internal pack  102  further comprises a male adhesive region  110  further comprising an adhesive material  112  and a plurality of dams  114 . In the preferred embodiment each hemostatic pack has at least one male adhesive region  110  and one female adhesive region  104  so that a plurality of packs can be chained together to form a contiguous blood impermeable barrier. In the preferred embodiment, the adhesive material  106  is the hook style of Velcro® type hook and loop fastener while the adhesive material  112  is the tufted style of Velcro® fastener. Thus when the adhesive regions  106  and  112  are brought into contact, they adhere to each other. The adhesive regions  106  and  112  are reversibly adherent to each other and may be separated by manual force, if desired. In another embodiment, the adhesive regions  106  and  112  may be fabricated from materials such as 3M Coban® and the like, hydrogel adhesives and the like, and typical adhesives such as are used in medical bandages. Thus, the hemostatic packs are provided with releasable attachment means, and any other suitable releasable attachment means may be use in place of those illustrated. The adhesive material gaps  108 , in the female adhesive region  104  are spaced and designed so that the dams  114  of the male adhesive region impinge on and seal against an impermeable surface of the female adhesive region  104 . The adhesive material gaps  108  and the dams  114  may be configured in a straight line or they may be curved into a wavy pattern to improve the sealing area. Special guide markers either printed on the packs  100  and  102  or fabricated as raised or detented surfaces on the packs  100  and  102  facilitate alignment of the dams  114  and the adhesive material gaps  108 . 
       FIG. 14B  illustrates a cross-sectional view of the internal packs  100  and  102  following joining to form a continuous barrier pack. Referring to  FIGS. 14A and 14B , the dams  114  seal against the impermeable surface  115  through adhesive material gaps  108 . The adhesive regions  106  and  112  are firmly in contact and grip each other to hold the two packs  100  and  102  together without any area of seepage, leakage, or weeping. The dams  114  and the corresponding receiving gaps  108  serve to block any flow of fluid through the hook and loop fastening system (which may initially be somewhat permeable to blood), as well as to provide guides to help doctors assembling a gang of packs assemble them without substantial gaps between adjacent packs. For a typical use, such as internal organ packs (a ruptured liver, for example), the device can be provided in dimensions of about 3 to 4 inches long, about 0.5 to 2 inches in diameter, so that a doctor may assemble several packs into a gang to form a substantial wall to cover a large fracture. 
     In yet another embodiment of the barrier pack, the mating region between the two packs comprises adhesive regions such as those described for  FIG. 14A , except that the barrier dams are replaced with fluid impermeable flaps that fold in to cover the adhesive regions following joining. One flap preferably covers each side of the adhesive region. In a preferred embodiment, the flaps cover the adhesive regions until they are needed to join with another barrier pack. At that time, the flap is pulled away, the two packs are joined, and the flap is folded in to cover the adhesive region and form a fluid-tight seal between the two barrier packs. 
     Referring to FIG.  1  through  FIGS. 14A and 14B , the hemostatic packing device  10  is used to treat wounds that are typically caused by trauma. In a typical procedure, the surgeon or medic, using aseptic procedure, accesses the wound either by open surgery or laparoscopic surgery. The wound is irrigated and cleaned and excess fluids are removed by suction and blotting with gauze sponges. The surgeon may apply antiseptic agents or thrombogenic agents to the wound. The surgeon places the hemostatic packing device  10  into the wound and the device  10  is secured into place. Using current damage control procedure, it is preferable to stabilize the patient prior to removing the hemostatic packing device  10  and permanently repairing the wound. The hemostatic packing device  10  does not stick or heal into the wound and removal is not traumatic to the patient. The hemostatic packing device  10  is also well suited for a typical “sucking chest wound” because of its inherent impermeable properties. In this use, the one-way valve  56  permits fluid and air to exit the chest cavity but prohibits reflux of air into the chest cavity, a condition which prevents lung function and which is known as pneumothorax. 
       FIG. 15  illustrates a preferred embodiment of a wound dressing or bandage  120 . The wound dressing or bandage  120  comprises a backbone  122  with a central region and two ends, a first fastener  126 , a second fastener  128 , a fluid-impermeable barrier  124 , a fluid dam  132 , a pillow pack  134 , and an optional peripheral hemostatic region  130 . The wound dressing or bandage  120  is configured to wrap around a body part, arm, leg, torso, head, etc. and fasten using the first fastener  126  and the second fastener  128 . The fasteners  126  and  128  are of the type including, but not limited to, Velcro, buckles, snaps, jam cleats, buttons, and the like. An optional cinch mechanism to increase mechanical advantage and allow the caregiver to apply the bandage  120  with increased compression may be added to the configuration. The backbone  122  is preferably a woven fabric of material such as, but not limited to cotton, polyester, polypropylene, polyurethane, polyethylene, PTFE, nylon, and the like. The woven backbone is configured to be flexible but have high tensile strength, while porosity is not an important characteristic. The impermeable barrier  124  is preferably applied to the central region of the bandage  120  and is created by a separate polymer layer that is adhered or welded to the backbone  122 . The backbone  122  may also be dipped, sprayed, or coated with materials such as, but not limited to, polyurethane, C-Flex thermoplastic, silicone elastomer, and the like. Since the dressing is intended for short-term application, gas permeability is not considered objectionable but it is desirable. The fluid dam  132  is fabricated from materials including those used to fabricate the fluid impermeable barrier  124 . The fluid dam  132  may also be fabricated from gel-filled membranes, hydrogels, oil-filled membranes, and the like. The membrane of the fluid dam  132  is preferably, inelastic at the pressures used for filling. The fluid dam  132  is configured to provide a pressure seal against the body and form a complete barrier to prevent blood from escaping the wound. In another embodiment, the fluid dam  132  is inflatable following or before application to the patient through a valve such as a stopcock or standard inflation valve on the exterior surface of the bandage  120 . 
     Further referring to  FIG. 15 , the pillow pack  134  is adhered to the central region of the bandage  120 , preferably to the fluid impermeable region  124 . The pillow pack  134 , preferably resides within the region described by the fluid dam  132 . The pillow pack  134  outer surface is preferably smooth and resistant to blood adherence but in another embodiment, the pillow pack  134  outer surface may be a fabric mesh or other convoluted surface capable of accelerating thrombosis or of carrying thrombogenic materials or antimicrobial agents. The pillow pack  134  is the primary distributor of force upon the wound to generate pressure tamponade. The pillow pack  134  is capable of extruding into a wound and distributing pressure evenly to generate hemostasis. The pillow pack  134  preferably comprises an elastomeric membrane filled with materials such as, but not limited to, air, water, oil, sand, gel materials, and the like. The pillow pack  134  in the embodiment where gas, air or liquid, is used for inflation, comprises an optional valve such as stopcock on the exterior surface of the bandage  120 . The peripheral hemostasis region  130  preferably resides within the fluid dam  132  and accelerates clotting in the region outside the wound area but within the environs of the bandage  120 . The peripheral hemostasis region  130  is fabricated from materials such as, but not limited to, cotton gauze, polyester knits and the like. 
     The present invention is suitable for wounds to many parts of the body. The external hemostatic pack works on the arms, the legs, the head, a finger, the torso, etc. The present invention also describes a band-aid type device with the further enhancement that a fluid-tight dam is comprised within the device to prevent blood loss out the side of the band-aid. 
     The present invention includes apparatus and methods for treating wounds. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore indicated by the appended claims rather than the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.