JP2009542353A - Growth-stimulated wound dressing with improved contact surface - Google Patents

Abstract

A wound contact material comprising an permeable material and a wound contact layer having a void extending from the contact layer to a depth of the permeable material. The wound contact layer can include a thin sheet or membrane that forms a generally flat and smooth wound contact surface with essentially no discontinuous surfaces or gaps. The wound contact layer can include a thin sheet of highly rolled fabric that forms a wound contact surface with an average surface roughness ranging from about 0 microns to about 200 microns. In a staged wound healing process, an embodiment of a wound contact material having a fabric contact surface is used in an early healing stage and a wound contact material having a membrane contact surface is used in a later healing stage. The wound contact material is particularly useful in a wound dressing used in wound treatment by the suction method.

Description

The present application relates generally to the field of bandages and other wound dressings. More specifically, the present invention relates to the field of wound contact materials that are applied in direct contact with a wound under a dressing or sealing dressing used in suction or negative pressure wound therapy.
(Refer to related applications)
This application is a continuation-in-part of US patent application Ser. No. 10 / 982,346, filed on Nov. 5, 2004, which is a provisional application filed on Apr. 13, 2004. Claim priority of 60 / 561,745. This application also claims the priority of US Provisional Patent Application No. 60 / 819,146, filed July 7, 2006.

  Wound healing is the basic repair process. It has been known for some time that treating wounds with the right material helps the natural regeneration process. Traditionally, such materials have been made from cotton fibers such as gauze. These dressings help the healing process by isolating the damaged tissue from external contaminants and removing wound exudates that can be harmful.

  As science and medicine have advanced, the technology incorporated into wound care devices has also been substantially improved. Highly absorbent wound contact materials are available that can absorb liquids many times their weight. Systems that temporarily seal wounds and remove exudate using suction have found wide application. Devices incorporating antibacterial agents and biological healing agents are widespread. Devices that provide a moist wound environment for enhanced healing have proven useful.

  However, many common conventional and current state of the art wound contact materials have several drawbacks, particularly for use in aspiration wound treatment. In one example, gauze and other similar flat fabrics are commonly used for wound dressings. As the gauze in contact with the wound gets wet with the wound exudate, it softens and softens, losing its structure and leaving little or no space for new tissue to grow on the wound surface. . When suction is applied to the gauze wound dressing, the dressing is compressed and flattened, virtually eliminating the space between the gauze fibers. In addition, trying to remove wound exudate from the gauze dressing by suction will not change the state that the gauze is fully moist and pressed against the wound, leaving no space above the wound. Growth is inhibited.

  In another example, a dressing that uses a foam material that is in contact with the wound can retain only a few small holes in the wound contact surface when suction is applied to the dressing. When a foam dressing is used with suction, the foam pores collapse and leave no space above the wound surface. If there is no significant open space above the wound surface, new tissue will enter the foam and grow. Periodic removal of the foam dressing destroys new tissue, causes excessive bleeding and causes unnecessary discomfort to the patient. Tissue ingrowth into the foam is a significant problem because there is no place for the tissue to grow other than to enter the collapsed bubble or pore structure of the foam.

In another example, a dressing that uses a wound contact material in the form of a relatively rigid perforated sheet, such as an Aquaplast ™ sheet, as a substrate to contact the wound is often comfortable on a wound surface with an irregular contour. And it is not flexible and compatible enough to fit. Dressings having such inflexible or rigid structural materials or wound contact layers result in unnecessary injury and discomfort to the patient. In addition, Aquaplast or similar sheets
Made of hard plastic with large holes in the plastic. Such sheets do not have small interconnecting gaps that facilitate draining liquid wound exudate from the wound surface. The holes in the Aquaplast sheet only serve as reservoirs that can store harmful wound exudates and delay wound healing. Since these large holes are not in fluid communication with each other, fluid removal is not practical. Furthermore, Aquaplast sheets do not provide any wicking action for effective removal of wound exudate. Aquaplast is also impermeable to gases and liquids, so it cannot breathe the wound where the sheet material contacts the wound surface and cannot efficiently drain fluid and wound exudate from the wound. .

  The wound dressing used in aspiration wound treatment preferably has some or all of the following characteristics and properties. The dressing should be flexible and conformal to the wound, the dressing can effectively drain wound exudate from the wound surface, and the dressing should be wound when applying suction so as not to impede the growth of new tissue. Sufficient voids remain on the top. The dressing must have a shape that maintains structural integrity even when wet and actively promotes tissue growth. When used at a later stage of tissue regeneration, the dressing prevents or minimizes healthy new tissue from entering the dressing material. Early in the treatment of a wound, there may be necrotic or dead tissue in the wound. This dead tissue can be a source of nutrients for harmful bacteria. The wound treatment dressing may have a wound contact surface adapted to debridement or remove dead tissue from the wound.

  As described in US patent application Ser. No. 10 / 982,346, which is assigned to the assignee of the present application and is a continuation-in-part of this application, wound dressings and wound contact materials are Has been developed to replace conventional gauze or foam pads under wound dressings or wound sealing dressings used in the wound healing process. Its purpose was to accelerate the healing process from the properties and shape of the wound contact material.

  One such wound contact material preferably comprises a permeable material having a plurality of indentations formed on the wound contact side of the contact material, wherein the indentations are provided in a randomly spaced pattern. The contact material is made of a permeable material having a gap connected to each other, so that harmful wound exudate can be effectively discharged from the wound surface. The contact material can be cut to a size that fits the wound and the cut piece is applied in contact with the tissue of the wound under the bandage or sealing dressing. Indented voids provide a hollow where new tissue can grow without over-entanglement with the permeable material, whereas porous foam pads are known to grow in entanglement To do. The contact element between the indentations provides the main tissue contact surface. The permeable material of the contact material provides sufficient compression resistance so that when the suction or other compression pressure is applied to the wound dressing, the indentation void does not collapse overall. In addition, the contact material maintains an indentation void in the presence of moisture.

  In addition to providing an empty growth space, the combination of the recessed void and the contact element is beneficial to the tissue when suction is applied to the wound dressing while pulling the tissue into a suspended shape within the void. Apply tension. These forces and the resulting tension on the tissue are thought to stimulate new tissue growth more effectively than the force obtained with suction therapy using a wound dressing with a generally flat surface when applied with suction. It is done.

Including a permeable substrate and a wound contact layer secured to the substrate side forming a wound contact surface, wherein the plurality of voids reach a certain depth within the substrate from the contact layer and on the wound contact surface It would be advantageous to provide an improved wound contact material that defines a wound contact element. In certain embodiments, it would be advantageous to provide a wound contact material having a wound contact surface that is adapted to prevent healthy tissue growth from becoming entangled with the contact material. In another example, it would be advantageous to provide a wound contact material having a wound contact surface adapted to debride the dead tissue from the wound so that healthy tissue to be revascularized can grow. The nature of the improvements and benefits that they confer will become apparent from the following description and exemplary embodiments.

  The present invention provides a wound contact material for use in a wound dressing. The contact material is particularly adapted for use in dressings that employ suction or negative pressure therapy to promote healing. The wound contact material includes a permeable material having a wound contact surface, and the wound contact surface includes a plurality of indentations and / or voids interposed between a plurality of wound contact elements. The material may contain a plurality of fibers connected to each other. Alternatively, the material may contain a polyester felt material.

  Certain embodiments of the present invention include a thin film secured to a permeable material to form a wound contact surface, the thin film covering the wound contact element and having an opening corresponding to a recess or void, the thin film being It is essentially smooth (ie essentially free of surface gaps) to prevent entanglement with new tissue growth. Another embodiment of the invention includes a thin fabric layer that adheres to the permeable material to form a wound contact surface, the fabric layer covering the wound contact element and having an opening corresponding to a recess or void. The fabric layer has small gaps or apertures that are intertwined with the necrotic tissue to allow debridement, and the apertures are smaller than the voids in the wound contact material.

These and other aspects and objects will become apparent from the description below.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and, together with the foregoing general description and the detailed description that follows, characterize the invention. Help explain.

  A wound dressing is provided that includes a wound contact material having a substrate and a discontinuous contact surface or layer that promotes tissue growth. The contact surface or contact layer contains a wound contact element and a void or indentation interposed between the wound contact elements. The substrate maintains the void such that empty space or void volume within the void provides room for tissue growth when the wound contact material is applied to the wound.

  The substrate of the wound dressing, specifically the wound contact material, is physically sufficiently robust so that it does not flatten out when a force is applied to the wound contact material against the wound surface. The force pressing the wound contact material against the wound surface includes, but is not limited to, a suction force applied to the wound dressing during the performance of negative pressure wound therapy. In addition, the wound contact material, particularly the substrate, is water-like, as opposed to many conventional wound contact materials becoming wet and softening and losing their geometry. Retains its structure when exposed to fluids or other body fluids.

  The substrate of the wound contact material is permeable, allowing for the transfer of suction near the wound surface and allowing fluid to be drawn from the wound. Although the substrate can be absorbent, it can retain its structure and resist changes even in the presence of moisture and watery liquids.

The void preferably reaches from the substrate to a depth of at least 0.1 mm above the wound surface when the wound contact material is applied to the wound surface. More preferably, the gap depth is between about 0.2 mm and about 5 mm. The width of the air gap defined by the empty space between the contact elements adjacent to the air gap is preferably greater than 0.1 mm. More preferably, the width of the gap is between about 0.5 mm and about 10 mm. The air gap may have any cross-sectional shape such as an oval, a circle, an irregular shape, or a square as shown in FIGS. 1A, 3A, 5A, and 8, for example. Further, since the wound contact element can be pedestal shaped, the gaps can intersect or be connected together to form a complementary shape with the pedestal contact element, for example as shown in FIG.

  Wound healing is recognized as a complex process. As described herein, when a wound dressing or wound contact material with a wound contact element and a gap interposed therebetween is pressed against the wound surface, a number of biology It is thought that a typical process occurs. In suction wound treatment using the wound contact material or wound dressing described herein, mechanical tension is applied to the underlying tissue. When suction is applied to the opening in the wound contact surface of the wound contact material, a force is applied that causes the tissue to form a catenary shape, thereby stretching the tissue partially into the void between the contact elements. It has been found that stretched tissues and cells are under tension, which causes cell growth and migration. By removing excess fluid exudate from the wound surface by aspiration, the growth of new granular tissue is further promoted. Periodically to another wound contact material with indentations spaced at random intervals so that various parts of the wound are in contact with the contact element one after another and / or exposed to the void. To promote growth across the entire wound surface.

  A fibrous material can be used to form the substrate for the wound contact material, and the fibrous material has any flexibility provided by the weaving technique. The fiber fabric can be formed into a structure suitable for use in a wound contact material by a variety of methods. These methods include knitting methods, weaving methods, embroidery, braiding, felt manufacturing methods, spunbond methods, melt blow methods, and melt spinning methods. Each of these methods can be further adapted to produce a material with an uninterrupted surface structure that includes the wound contact elements and void spaces described herein. During the production of the dough material, the structure can be provided, for example, by directly applying the molten fiber to a mold such as that used in the meltblowing process. Alternatively, the structure can be formed by processing the dough material formed after manufacture, for example, by hot stamping or vacuum forming. It is also possible to mix an adhesive with a fiber material or a fabric material and spray it onto the textured surface.

  The flexibility of fiber fabrics extends to ease of adaptation to complex applications. Individual fiber materials may be varied to optimize physical parameters such as stiffness or flexibility. Individual fiber materials can also be selected for their well-known ability to aid wound healing. Examples of the fiber material are calcium alginate and collagen. Alternatively, the fibers may be treated with well-known wound healing agents such as hyaluronic acid or antibacterial silver. The proportion of fiber material can be varied to suit the wound requirements. In accordance with certain desirable aspects of the invention, various fibers with a variety of wound healing properties may be added as desired.

  A wound contact material comprising fibers also has the advantage of being somewhat conformal to a roughly irregular wound surface. Also, the fiber fabric can be formed into a structure having a large number of small interlinked spaces between connected or intertwined fibers. The gaps connected to each other in this way allow or assist the drainage of harmful wound exudate from the wound surface. The number, size and orientation of the gaps can be controlled and optimized depending on the fabrication method employed to fabricate the fibrous contact material.

  In one example, the substrate includes intertwined fibers that define gaps or gaps therebetween. The gap provides a space for liquid and gas to be aspirated from the wound, so that the substrate is generally permeable. The gap is smaller than the void created in the substrate, based on the average cross-sectional area or nominal diameter. Usually the gap is less than half the size of the gap, and in some cases much smaller than the gap. In the exemplary wound contact material 300 illustrated in FIGS. 3A-3E, the void 304 has a diameter in the range of about 1000 microns to about 2000 microns at the wound contact surface 310. The air gap 304 typically penetrates or reaches a depth in the range of about 250 microns to 1000 microns. In contrast, the gaps or gaps between fibers throughout the substrate are typically from about 0 microns to about 400 microns.

  Other fibrous structures that are expected to be beneficial additions include (1) fluid absorbent fibers, (2) non-absorbable fibers, (3) bioabsorbable fibers, and (4) wicks that draw fluid from the wound surface. King fibers, (5) fibers with known healing effects such as calcium alginate, (6) biodegradable fibers that control the release of healing agents, (7) conductive fibers that deliver charge or current, (8) undesired tissue , Adhesive fibers that selectively remove substances or microorganisms, and (9) non-adhesive fibers that protect sensitive fibers.

  One exemplary embodiment of a wound contact material is illustrated in FIG. Grooved wound contact material 100 generally includes a conformable substrate 102 and contains a wound contact surface 110. The substrate 102 is preferably made from a polyester material. The polyester material can contain a polyester fabric such as felt, knitted fabric, woven fabric or blade. Creep resistance, as shown by polyester, is particularly desirable because it allows the substrate 102 to retain its structure when exposed to moisture and when subjected to compression by forces such as suction applied to the wound dressing. Felt materials such as Masterflow RTM manufactured by the BBA Group (Wakefield, Mass., USA) have the advantage that the interstitial gap facilitates fluid drainage from the wound surface. The substrate can further contain a polyolefin such as polyethylene or polypropylene. The substrate can further contain a polyamide such as nylon. Wound contact surface 110 is discontinuous and contains void grooves 104 that are sandwiched between wound contact elements 106. The void groove 104 reaches a depth that enters the substrate 102 and provides an empty space in which new tissue can grow. The discontinuities or openings in the wound contact surface 110 promote new tissue growth.

  In use, the grooved wound contact material 100 is pressed against the wound and brought into direct contact with the wound surface. Apply pressure of 0.1 PSI (5 mm Hg) or higher applied by aspiration or other means to press the wound contact surface 110 against the surface of the wound and bring the wound contact element 106 into direct contact with the injured tissue and the void 104 It is desirable to leave the wound surface open to accept new tissue growth. Preferably, the suction force is applied in the range between about 0.25 PSI (12 mmHg) to about 5 PSI (260 mmHg). More preferably, the suction force is applied at a level between about 0.67 PSI (35 mmHg) and about 1.45 PSI (75 mmHg).

  2A and 2B illustrate a wound composite contact material 200 that includes a grooved contact material 100 and a vapor permeable backside adhesive sheet 202. Vapor permeable backside adhesive sheets are generally well known in the art and are believed to contribute to wound healing by maintaining an optimal moisture level for a wound. In use, the wound composite contact material 200 is applied to the wound surface with the wound contact surface 100 of the grooved wound contact material 100 in contact with the wound. The adhesive sheet 202 covers the wound contact material 100, adheres to the skin adjacent to the wound, secures the contact material 100 to the wound, and protects the wound from bacteria and other external contaminants and / or scratches, Permeate water vapor from the wound.

  3A through 3E illustrate a recessed wound contact material 300 that includes a substrate 302 and a wound contact layer 320 having a wound contact surface 310. When the wound contact material 300 is used to treat a wound, the wound contact layer 320 is disposed proximal to the wound and the substrate 302 is disposed distally therefrom. The substrate 302 can be constructed using materials and fabrication methods similar to those employed for the grooved wound contact material 100. As illustrated in FIG. 3A, the wound contact layer 320 is preferably relatively thin compared to the substrate 302. The wound contact layer 320 can be fused or bonded to one side of the underlying material 302. Alternatively, the wound contact layer can be integrally formed with the substrate 302 as illustrated in FIGS. 9A-9D. The wound contact layer 320 and the substrate 302 can be made of the same material or different materials.

  As best shown in FIGS. 3B and 3D, the wound contact material includes a plurality of recessed voids 304 that are generally surrounded by wound contact elements 306. The indentation gap 304 extends from the opening 312 of the contact layer 320 to a certain depth of the substrate 302. Preferably, the recessed void 304 occupies at least about 25% of the total area of the wound contact surface 310 in total area. More preferably, the total area of the recessed voids occupies at least about 50% of the total area of the wound contact surface. The recessed gap 304 is partially defined by the side wall 308. The sidewall 308 provides rigidity and helps resist compression of the indented wound contact material 300 under the compressive force generated by suction or by contacting and fixing the wound contact material 300 to the wound. The wound contact element 306 is generally flat. However, in certain embodiments, each wound contact element 306 may be configured to provide an arcuate contact surface with a contact radius of about 0.1 mm to about 1 mm.

The indentation gap 304 can be formed in a variety of regular or irregular shapes, such as those illustrated in FIGS. 1A, 3A, 5A, 7, 8. In some embodiments, the void 304 can be configured not to “undercut” such that the recessed void 304 is no larger than its corresponding opening 312 at the nominal diameter or circumference. (Undercut voids would be characterized by the size of the mouth of the opening being smaller than the size of the corresponding internal void, as measured, for example, in diameter or perimeter for a generally circular opening. For non-circular openings and voids, other relevant dimensions can be used, such as the outer edge or average width.)
In certain embodiments, the substrate 302 of the wound contact material 300 is made from Masterflow RTM. In another embodiment, the substrate 302 is made from a polyester needle felt. The substrate 302 has a thickness in the range of about 1.0 mm to about 1.5 mm. Recessed voids 304 are formed in the material 302, and the average depth of the recessed voids 304 is about 0.75 mm and the average diameter is about 2 mm. The indentation void 304 may be formed in the material 302 prior to attaching to the wound contact layer 320, or the wound contact layer 320 may first be attached to the material 302 and then the void 304 may penetrate the wound contact layer 320. (To create the opening 312), and even material 302 may be formed (to create the recessed void 304).

  The wound contact material 300 is regularly replaced at intervals ranging from several hours to several days after being applied to a normal wound. Because tissue growth occurs preferentially in the area of the gap 304 compared to the area of the wound contact element 306, the indentation gap 304 and the wound contact element 306 of the replacement wound contact material 300 are indented in the old wound contact material 300. Preferably, the gap 304 and the wound contact element 306 are positioned so that they are not generally aligned with the area where they exist. Thus, several approaches can be employed to change the positioning of the indentation gap 304 and the contact element 306 within the wound to facilitate the creation of new tissue throughout the area of the wound. In one example, the indentations 304 are randomly arranged so that the indentations 304 do not align one site of the wound contact material with another. In another example, the wound contact material 300 can be provided with indentations 304 having various diameters within the same wound contact material 300 or between successive wound contact materials 300. In yet another example, the wound contact material 300 may be provided with various spacings and voids 304 within the same wound contact material 300 or between successive wound contact materials 300.

  As illustrated in FIGS. 3B and 3C, the indentation gap 304 only reaches partway through the material 302 from the wound contact surface 310 and is hidden within the substrate 302. In one variation of the wound contact material 300, contact elements 306 corresponding to the indented voids 304 are disposed on both the upper and lower surfaces of the indented wound contact material 300, ie, the contact material 300 contacts the contact material 300 to the wound. When indented, it has a well cavity 304 and a wound contact element 306 that are both proximal and distal to the wound surface. In another variation, some or all of the recessed voids 304 span the entire thickness of the substrate 302.

When using the contact material for wound 300, the hollow space 304 can be partially filled with a substance having a healing effect. For example, a disinfectant may be placed in the void 304 to treat the infected wound. Also, a biological healing agent could be delivered to the void 304 to increase the rate of new tissue formation. Further, the wound contact material 300 could have different functions on each side. In one example, one side of the contact material 300 could be optimized for new tissue growth and the opposite side of the contact material 300 could be optimized for antimicrobial delivery. In another example, one side of the contact material 300 has small gaps or uneven areas that are optimal for debridement of necrotic cells from the wound, while the opposite side of the contact material 300 is intertwined with new tissue growth. It would be possible to have a contact element 306 with a smooth contact surface 310 to prevent this.

  As specifically shown in FIGS. 3A and 3D, the wound contact layer 320 is applied to one side of the substrate 302 to form an impermeable thin film that forms a wound contact surface 310 that includes a wound contact element 306 and an indentation void. And an intervening opening 312 corresponding to 304. The impermeable membrane is preferably a polyester membrane made from polyethylene terephthalate (PET) resin such as that sold under the trademark Mylar ™. Other membrane materials may be used including but not limited to silicon, acetylcellulose, vinyl, urethane, or polylactic acid. The membrane of the contact layer 320 is relatively thin compared to the permeable material 302 from which the voids 304 extend. Available membranes having a thickness of about 0.51 millimeters (0.020 inches) or less are generally sufficient, and membranes having a thickness of about 0.102 millimeters (0.004 inches) or less are preferred. In one embodiment, a membrane having a thickness of about 0.0127 millimeters (0.0005 inches) is used. The membrane is a generally smooth surface that minimizes gaps or openings that allow tissue to grow and become entangled. In this way, almost all tissue growth enters the void 304, so that there is little tissue rupture when the wound contact material 300 is pulled away from the wound, minimizing patient discomfort.

  The wound contact surface 310, including the membrane layer 320, can be further peeled away from the healing wound tissue by applying a coating, such as a hydrogel, to the wound contact layer 320. In a preferred embodiment, the membrane is a plastic membrane, and when the polymer hydrogel is cross-linked to the plastic membrane to remove and replace the wound contact material 300, delamination and the potential of the gel into the wound Form a hydrogel laminate to prevent indwelling. By providing a cold, wet and slippery contact surface 310 to the wound contact layer 320 of the contact material 300, the gel can be removed from the wound with minimal tissue rupture and discomfort.

  In some embodiments, the membrane layer 320 can include a meltable membrane. One or more drugs or other agents can be integrated into the meltable film. When the membrane melts in the presence of moisture, the drug or agent is released.

  As specifically shown in FIG. 6, the wound contact material 600 includes a substrate 602 and a wound contact layer 620 on one side of the material 602. The wound contact layer 620 is attached to the substrate 602 to form a wound contact surface 610 containing the wound contact element 606 and a thin sheet of permeable nonwoven and intervening openings 612 corresponding to the recessed voids 604 reaching the material 602. Including. This permeable fabric sheet is highly rolled by pressing the fabric between rollers or plates to exhibit a generally uniform or glossy surface with an average surface roughness of about 0 microns to about 200 microns with gaps. Since this has small surface gaps or uneven areas, the contact material 600 with the contact layer 620 can be advantageously applied to the wound healing stage where the benefit of tangling some tissue with the wound contact material 600 is obtained. Specifically, some wounds may show necrotic tissue at an early stage. It is preferred to debride the necrotic tissue from the wound when changing the wound contact material. Thus, dead or necrotic tissue is provided by providing a contact layer 620 that facilitates the adhesion of such tissue in the early stages of wound healing, and further removing it when the wound contact material 600 is peeled from the wound. Can be removed. The removal of necrotic tissue thus done promotes healthy new growth when a new wound contact material is applied.

  The preferred fabric sheet for forming the contact layer 620 is a spunbond (nonwoven) low lint 100% polyester fiber fabric, although other synthetic fibers such as spunbond polypropylene and spunbond composite fibers are also possible. It can be rolled to a sufficiently fine flat surface. The fabric is preferably no more than about 0.51 millimeters (0.020 inches) thick, and more preferably is about 0.102 millimeters (0.004 inches) thick.

  One or more wound contact materials 600 including a fabric contact layer 620 having small surface gaps or irregular areas, each having a different effect on the different contact layers 620, 320 in the early and late stages of healing, respectively Together, it is advantageous to provide a staged healing kit that includes one or more wound contact materials 300 that include a membrane contact layer 320 that is essentially free of surface irregularities or gaps. The wound contact material in the kit removes the necrotic tissue with the contact material 600 including the cloth contact layer 620 early in the healing process, and the patient contact with the contact material 300 including the membrane laminate contact layer 320 later in the healing process. It can be used to reduce pleasure.

  A recessed contact material, such as a wound contact material 300, is illustrated in FIGS. 4A, 4B, and 4C. In particular, FIG. 4A shows the wound surface 400 before applying the wound contact material, FIG. 4B shows the wound surface 400 while applying the wound contact material, and FIG. 4C shows the wound after removal of the wound contact material. Shows the surface. The wound surface 400 may be part of a wound including, for example, all or most of a small surface portion of a shallow surface wound or deep tissue wound. As illustrated in FIG. 4B, the wound contact element 306 directly contacts the wound surface 400 and new tissue growth 410 protrudes from the wound surface 400 into the indentation cavity 302 of the wound contact material 300. The wound contact material 300 can be pressed against the wound surface 400 by suction or by other means such as tape the contact material 300 to the skin around the wound, or by wrapping the contact material 300 and the affected area. As illustrated in FIG. 4C, when the wound contact material 300 is removed, the new tissue growth 410 remains intact.

  As shown in FIGS. 5A and 5B, a rough irregular wound contact material 500 is a rough wound contact surface 510 that includes a substrate 502 and irregular voids 504 that intervene in irregular contact elements 506. Including. The irregular contact element 506 can function as a “cane” member that is adapted to contact and adhere to necrotic tissue when the contact material 500 is applied in contact with the wound. When the contact material 500 is removed from the wound, the gangrene tissue adhered to the hook-shaped protrusion 506 is debleed and removed from the wound. Since necrotic tissue is a nutrient source of harmful bacteria, removal of necrotic tissue is an important part of wound healing.

  Even after removal of the necrotic tissue, the wound may still be infected, thus inhibiting healing. The material 502 of the wound contact material 500 can include an antimicrobial agent such as antimicrobial silver, which helps kill bacteria. The removal of necrotic tissue and the killing of bacteria present in the wound can help the wound enter a growth stage where new tissue is formed. The continuous use of the wound contact material 500 containing an antibacterial agent promotes the growth and proliferation of new cells and tissues because it can maintain low bacterial levels in the wound and promote healing. By adding another growth promoter to the material 502 of the wound contact material 500, the growth of new cells can be further promoted.

As shown specifically in FIG. 5B, the irregular wound contact material 500 has voids 504 and contact elements 506 with random cross-sectional shapes. The material 502 of the contact material 500 may be made from a polyester felt or a core material. In some embodiments, the felt is roasted with hot air to melt a proportion of the felt fibers to form a textured surface 520 with a number of ridge elements 506. In another embodiment, the saddle-like element 506 can mimic what is typically used with Velcro. The irregular surface 510 of the irregular contact material 500 can also be formed by passing the material 502 through convective heat at or near the melting point of the material including the material 502.
For example, polyester materials typically melt in the range of about 250 ° C to about 290 ° C. When the polyester felt material is passed through a convective heat source operating in this temperature range for a short time, the surface melts and then the polyester yarn on the surface fuses. The degree to which the surface melts can be controlled by temperature and exposure time to achieve a desired roughness surface 510 that exhibits irregular voids 504 and irregular contact elements 506. Although the irregular contact material 500 is shown as having only one uneven surface 510, the upper and lower surfaces of the contact material 500 may be uneven as well. The wound contact material 500 having concave and convex surfaces on both sides will be useful, for example, for treating a digging wound.

  As shown in FIG. 7, the wound contact material 700 includes a substrate 702 and a plurality of wound contact elements 706 that define a void space 704, each wound contact element having a wound contact layer 720. When the contact material 700 is applied to the wound, the contact layer 720 of the pedestal-shaped wound contact element 706 contacts the wound surface and the void space 704 remains free for tissue growth. The substrate 702 has sufficient resistance to the compressive force of the therapeutic suction to maintain an empty void space 704 near the wound surface when suction is applied to the wound. In certain embodiments, the wound contact layer 720 includes a thin film having minimal surface cuts or gaps, as described above with respect to the embodiment of FIGS. 3A-3E. In another embodiment, the wound contact layer 720 includes a thin sheet of nonwoven as described above with respect to FIGS. 6A-6D. In yet another embodiment, the wound contact layer 720 is integrated with and is part of the substrate 702.

  As illustrated in FIG. 8, the wound contact material 800 includes a substrate 802 having a plurality of generally square or square voids 804 and a wound contact surface 810 that includes a wound contact element 806. Wound contact surface 810 can be formed from wound contact layer 812.

The treatment with the wound contact material described herein is most effective when the contact material is held in direct contact with the wound surface. The contact material is preferably held at a pressure of at least about 0.1 PSI (5 mmHg). Typically, the wound site is sealed with a suitable dressing and suction is applied to the dressing under the dressing. Recessed wound contact material 300 has its structure containing voids 304 so that material 302 remains empty inside the voids under the compressive force of suction and in the presence of moisture and other wound exudates. Because it is designed to stay, it is particularly well adapted to the application of suction. As illustrated generally in FIG. 4B, the wound contact material 300 is arranged such that the wound contact surface 310 contacts the wound surface and the void 304 is open on the wound surface. Typically, the suction force is applied at a level in the range between about 0.25 PSI (12 mmHg) to about 5 PSI (260 mmHg). Preferably, the suction is applied at a level between about 0.67 PSI (35 mmHg) and about 1.45 PSI (75 mmHg). By applying a wound packing material to the back of the wound contact material as part of the wound dressing, the suction effect can be further enhanced. One wound packing material suitable for this is described in US patent application Ser. No. 10 / 981,119, filed Nov. 4, 2004.
Case study 1
Patient A is a 70-year-old male with stage IV pressure ulcers dug down significantly on his right hip. A wound contact material containing a substrate of the present invention and a wound contact surface was applied to the wound and an adhesive film was applied over the wound and wound contact material. A force of about 1.1 PSI was applied under the adhesive film to apply force to the wound. Aspiration was maintained substantially continuously. The wound contact material was changed every 2 to 4 days. After using the wound contact material for 30 days, the wound site was nearly healed and the wound area was reduced from 66 square centimeters to 45 square centimeters. A split skin graft was applied to the wound.
Case study 2
Patient B is a 50 year old male with a fractured right ankle and exposed bone. The plate was used to reduce the fracture, and a rectus abdominal muscle free flap was performed to cover the exposed bone and metal fittings. Only a portion of the flap survived, leaving open bones in the exposed bone and metal fittings. The wound contact material of the present invention was applied to a wound, and an adhesive film was applied on the wound and the contact material. A force was applied to the contact structure by wrapping an elastic bandage around the ankle and / or applying a suction force. About half a day of suction was applied to the whole, and the bandaging force was maintained for the remaining half day. Over the course of several days, he applied force only using the bandage. When the force was applied by suction, a suction force between about 1 PSI and about 2 PSI was utilized. Within two weeks, a new organization has grown on the exposed hardware. Within 7 weeks, the wound area decreased from 50 square centimeters to 28 square centimeters.

  While preferred embodiments of the invention have been illustrated and described herein, it will be understood that the embodiments are provided by way of example only. Many variations, modifications and alternatives will occur to those skilled in the art without departing from the spirit of the invention. Accordingly, the appended claims are intended to cover all such modifications within the spirit and scope of the invention.

1 is a perspective view of a grooved wound contact material according to an exemplary embodiment of the present invention. FIG. 1 is a perspective view of a grooved wound composite contact material according to an exemplary embodiment of the present invention. FIG. 2B is a cross-sectional view of the grooved wound composite contact material of FIG. 2A. FIG. 1 is a perspective view of a recessed wound contact material according to an exemplary embodiment of the present invention. FIG. FIG. 3B is a top view of the indented wound contact material of FIG. 3A. FIG. 3B is a bottom view of the indented wound contact material of FIG. 3A. FIG. 3B is a cross-sectional view of the indented wound contact material of FIG. 3A. FIG. 3B is an enlarged cross-sectional view showing in detail one indentation of the indented wound contact material of FIG. 3A. FIG. 3B is a cross-sectional view illustrating a method of using the indented wound contact material of FIG. 3A. FIG. 3B is a cross-sectional view illustrating a method of using the indented wound contact material of FIG. 3A. FIG. 3B is a cross-sectional view illustrating a method of using the indented wound contact material of FIG. 3A. 1 is a perspective view of an irregular wound contact material according to an exemplary embodiment of the present invention. FIG. FIG. 5B is a cross-sectional view of the irregular wound contact material of FIG. 5A. 1 is a perspective view of a recessed wound contact material according to an exemplary embodiment of the present invention. FIG. 1 is a perspective view of a wound contact material according to an exemplary embodiment of the present invention. FIG. 1 is a perspective view of a wound contact material according to an exemplary embodiment of the present invention. FIG. 1 is a perspective view of a recessed wound contact material according to an exemplary embodiment of the present invention. FIG. FIG. 9B is a top view of the indented wound contact material of FIG. 9A. FIG. 9B is a bottom view of the indented wound contact material of FIG. 9A. FIG. 9B is a cross-sectional view of the indented wound contact material of FIG. 9A.

Claims (40)

A wound contact material for use in the treatment of wounds by suction, the wound contact material comprising a permeable material and a wound contact layer on the permeable material, wherein the wound contact layer is a wound contact surface The wound contact material extends from the contact layer to a depth of the permeable material and has a plurality of voids defining a wound contact element on the wound contact surface. Contact material. The void is a void void, and the permeable material is aspirated into the wound dressing in wound treatment by aspiration to maintain the hollow void in which the void void allows tissue to grow from the wound surface. The wound contact material according to claim 1, which has resistance to compression when force is applied. Wherein the applied suction force is at least 6.89 × ¹⁰ 2 Pa (about 0.1 psi), wound contact material according to claim 2. The wound contact material of claim 3, wherein the applied suction force is between 1.72 × 10 ^{3 to} 3.45 × 10 ⁴ Pa (about 0.25 PSIG to about 5.0 PSI). The wound contact material of claim 4, wherein the applied suction force is between 4.62 × 10 ^{3 to} 1.00 × 10 ⁴ Pa (about 0.67 PSI to about 1.45 PSI). The voids are connected to each other so as to define a substantially separate wound contact element on the wound contact surface, and the permeable material causes the interconnected voids to grow tissue from the wound surface. The wound contact material of claim 1, wherein the wound contact material is resistant to compression when a suction force is applied to the wound dressing in a wound treatment by suction to maintain a possible hollow. The void is a groove-type void, and the osmotic material is used for the wound dressing in wound treatment by suction so that the groove-shaped void maintains a hollow where tissue can grow from the wound surface. The wound contact material according to claim 1, which has a resistance against compression when a suction force is applied to the wound contact material. The wound contact material of claim 1, wherein the thin film comprises a thin plastic sheet. The wound contact material according to claim 1, wherein the thin film includes a film selected from the group consisting of a polyester film, an acetylcellulose film, and a vinyl film. The wound contact material according to claim 9, wherein the polyester film is formed of polyethylene terephthalate. The wound contact material of claim 1, wherein the thin film has a thickness of about 0.51 millimeter (0.020 inches) or less. 12. The wound contact material of claim 11, wherein the thickness of the thin film is about 0.004 inches or less. The wound contact material of claim 12, wherein the thickness of the thin film is about 0.0005 inch. The wound contact material of claim 1, further comprising a coating on the wound contact surface of the wound contact layer. The wound contact material of claim 14, wherein the coating is a hydrogel coating. The wound contact material of claim 15, wherein the hydrogel coating is cross-bonded to the wound contact layer. A wound contact material for use in a wound treatment by suction, the wound contact material comprising a permeable material and a wound contact layer on the permeable material, the contact layer forming a wound contact surface The wound contact material has a plurality of voids extending from the contact layer to a depth of the permeable material to define a wound contact element on the wound contact surface; Wound contact material. The void is a void void, and the permeable material is aspirated into the wound dressing in wound treatment by aspiration to maintain the hollow void in which the void void allows tissue to grow from the wound surface. 18. A wound contact material according to claim 17, which is resistant to compression when force is applied. Wherein the applied suction force is at least 6.89 × ¹⁰ 2 Pa (about 0.1 psi), wound contact material according to claim 18. 20. The wound contact material of claim 19, wherein the applied suction force is between 1.72 x 10 < ³ > to 3.45 x 10 < ⁴ > Pa (about 0.25 PSIG to about 5.0 PSI). 21. The wound contact material of claim 20, wherein the applied suction force is between 4.62 x 10 < ³ > to 1.00 x 10 < ⁴ > Pa (about 0.67 PSI to about 1.45 PSI). The voids are connected together to define a substantially separate wound contact element on the wound contact surface, and the permeable material allows the interconnected voids to grow tissue from the wound surface. 19. The wound contact material of claim 18, wherein the wound contact material is resistant to compression when a suction force is applied to the wound dressing in a wound treatment by suction to maintain a possible hollow. The void is a groove-type void, and the osmotic material is used for the wound dressing in wound treatment by suction so that the groove-shaped void maintains a hollow where tissue can grow from the wound surface. The wound contact material of claim 18, which is resistant to compression when a suction force is applied thereto. 19. The wound contact material of claim 18, wherein the fabric is rolled to exhibit a generally smooth surface having an average surface roughness in the range of about 0 microns to about 200 microns. 19. The wound contact material of claim 18, wherein the fabric is selected from the group consisting of spunbond polyester, spunbond polypropylene, and spunbond composite fibers. 19. The wound contact material of claim 18, wherein the fabric thickness is about 0.51 millimeter (0.020 inch mil) or less. 27. The wound contact material of claim 26, wherein the fabric thickness is about 0.004 inches or less. A wound dressing for use in a wound treatment by suction, said wound dressing comprising a plurality of gaps connected to each other for draining fluid from said wound and a plurality of depths reaching a certain depth of said wound dressing A wound contact surface having a void, wherein the wound dressing has sufficient compression resistance to maintain a hollow space in the void under the compressive force of suction therapy and promotes tissue growth in the void space , Dressing for wounds. 29. A wound dressing according to claim 28, wherein the wound contact material comprises synthetic fibers and the interconnected gaps are disposed between the fibers. 29. A wound dressing according to claim 28, wherein the average size of the gap is larger than the average size of the gap. 32. The wound dressing of claim 30, wherein the average size of the gap is twice the average size of the gap. 29. The wound dressing of claim 28, wherein the average size of the gap between the fibers is less than about 400 microns and the average diameter of the voids is greater than about 1000 microns. 30. The wound dressing of claim 28, wherein the wound contact surface is impermeable. 30. The wound dressing of claim 28, wherein the wound contact surface is permeable. 30. The wound dressing of claim 28, wherein the voids are connected to each other and the wound contact surface includes a pedestal wound contact element. Having a plurality of voids comprising a permeable material and a wound contact surface and defining a wound contact element on the wound contact surface extending from a contact layer to a depth of the osmotic material; In a wound treatment method by suction using a wound contact material,
Directing the wound contact surface to the wound surface and applying the wound contact material to the wound;
Sealing the wound site with a conformal dressing;
Applying a suction force to the wound contact material under the dressing. 37. The wound treatment method of claim 36, wherein a suction force of at least about 6.89 x 10 < ² > Pa (about 0.1 PSI) is applied. 38. The wound treatment method of claim 37, wherein a suction force of 4.62 × 10 ^{3 to} 1.00 × 10 ⁴ Pa (about 0.67 PSI to about 1.45 PSI) is applied. The wound treatment method of claim 36, wherein the wound contact material further comprises a thin film forming the wound contact surface. 38. The wound treatment method of claim 36, wherein the wound contact material further comprises a thin sheet of nonwoven fabric that forms the wound contact surface.

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