ABSORPTIONAL BODY FOR APPLICATION TO HUMAN OR ANIMAL SKIN SURFACES

Description

[0001] The invention relates to a mixture of a quantity of strongly osmotically active substances produced on the basis of acrylic acid, with a quantity of osmotically comparatively weak or osmotically inactive substances for use in a method for the treatment of chronic wounds, edema therapy or the treatment of leg ulcers, for absorbing harmful proteases, wherein the mixture is present in an inner layer which essentially consists of the mixture, wherein the inner layer is enclosed by an outer covering which is permeable to liquids, wherein the inner layer and the outer covering form an absorbent body for application to human or animal skin surfaces in the area of ​​wounds.

[0002] An absorbent core is disclosed in German patent DE 100 59 439. The known absorbent core has proven effective in practice; however, there is a need to increase its absorbency, particularly in the case of moderately to heavily exuding, infected wounds, from which the wound exudate can be drawn more effectively from the wound bed. Another absorbent core is disclosed in US patent 5998032.

[0003] This problem is solved by the mixture according to claim 1. Further embodiments are the subject of the dependent claims.

[0004] In the absorption body containing the mixture according to the invention, the inner layer is filled with osmotically active substances in such a way that an osmotic pressure can be exerted on a wound with the wound fluids contained therein, by means of which the wound fluid can be drawn away from the organism to be treated and thus interstitial normohydration of tissue can be supported both in the superficial wound region and in the tissue depth, by directing the body's own fluids in their flow direction towards the skin surface of the patient into the absorption body.

[0005] According to the invention, the inner layer is designed such that the areal mass is at least 420g / m 2<, wherein the areal mass of the uniformly distributed portion of the osmotically active substances therein is at least 200g / m 2<.

[0006] The concepts of chronic wound treatment and edema therapy are often inseparable, as inflammatory processes, infectious events and vascular leaks occur in both types.

[0007] When edematous fluid, resulting from pathological processes, enters the cells of a tissue, these cells become compressed. Their distance from nourishing or draining vessels increases, diffusion processes become impaired, metabolic products accumulate, and oxygen becomes scarce. Furthermore, metabolic products leak from dying cells, causing sugar breakdown products such as lactic acid (lactate from glycolysis) or citric acid to accumulate, leading to active collagen degradation and tissue destruction.

[0008] According to hypotheses, this tissue breakdown, which is similar to wound formation, is subject to a multitude of other processes. Activated leukocytes, growth factors trapped by fibrin (growth factor trap hypothesis), and hypoxic areas support tissue breakdown.

[0009] The causes of impaired potency lie in the presence of overhydration and prolonged fluid retention in the tissue. One therapeutic approach that addresses this is vacuum therapy, in which the wound area is subjected to specific negative pressure using closed systems. The healing results are impressive.

[0010] A disadvantage is that this therapeutic approach is a very expensive, complex process requiring specialized equipment. It is therefore advantageous to apply analogous mechanisms via other physical principles of the wound region, for example, via a dressing encompassing the inventive mixture under high osmotic pressure. Oversized quantities of water-retaining polymers, e.g., 200 g / m², fulfill this purpose and take advantage of the fact that water molecules only relinquish contact with other water molecules under high separation force. The fact that a molecule as small as water must be heated to 100°C to achieve this separation confirms this.

[0011] The suction effect of surface water molecules also reaches water molecules in deeper tissue layers, where excess aqueous exudates are drawn out. The cohesive forces of the water allow for the chain-like removal of water molecules all the way to the site of origin of the edema.

[0012] This suction effect offers a multitude of benefits. Collagen-degrading substances, such as citric or lactic acid, which are present in the edema and actively maintain the wound, are removed. Diffusion processes become easier again, and the cells receive oxygen, building blocks, and mediators such as growth factors. Collagen synthesis can then begin.

[0013] By utilizing the unwanted exudate as a carrier substance and as a rinsing agent for the wound area, substances contained in the exudate are flushed through several tissue layers and cleanse the layers of the wound.

[0014] Known wound dressings with superabsorbent substances have the property of binding exuding fluid to prevent noticeable leakage. While a "deep penetration" is mentioned, it is not defined. In contrast, the present absorbent core, comprising the inventive mixture, achieves a deep penetration effect, for example in the case of leg ulcers (venous leg ulcers), reaching as far as the insufficient vein and thus the perivenous tissue and its edema. Through a swelling process within the absorbent core, adaptation to the wound bed is achieved, in the sense of wound morphology adaptation, since the saturated superabsorbent granules are mobile.

[0015] The absorbent core comprising the mixture according to the invention can be present in a dressing as a combination product. It can be embedded within additional pockets or coverings made of perforated films, similar to wound contact layers. In this case, it can also be used in conjunction with other dressing materials, such as foam dressings, alginates, hydrophilic fibers, polyhexanides and carriers, CMC (carboxymethylcellulose), hydrophilic fibers, hydrocolloids, lipocolloids, honey, activated charcoal, silver, cellulose, pharmaceuticals, hydrogels, detergents such as surfactants and poloxamers and their carriers, other superabsorbent materials, or mixtures of such devices.Depending on the application, the product can be placed with one side facing the wound, where the absorbent core has indirect contact with the wound; alternatively, it can be oriented with the other type of dressing towards the wound, in which case the dressing forms a flow body through which the absorbent core draws the exudates, thus increasing its absorption capacity and prolonging its contact time with the wound.

[0016] The dressing can consist of more than one film or covering, for example, a nonwoven fabric on one side and a waterproof or vapor-permeable backsheet on the other. Another possibility is to use a three-dimensionally shaped wound contact layer on the one hand and a covering with special functions, such as carrying activated charcoal or anti-infectives, etc., on the other. Two homogeneous coverings or a mixture of different coverings are also possible.

[0017] The covering, consisting of one or more blanks, is preferably bonded, ultrasonically welded, thermally generated, or mechanically welded. Preferably, the seam does not form the outer edge of the product, but leaves an unstitched portion of material with flexible and soft product edges, either single- or multi-layered. This covering may be partially or completely closed around its circumference, remain open along at least one length, or have folds.

[0018] In addition to products being spatially adjacent to the absorbent core within a covering, the aforementioned substances, such as foam dressings, alginates, hydrophilic fibers, polyhexanides and carriers, CMC, hydrocolloids, lipocolloids, honey, activated carbon, silver, cellulose, pharmaceuticals, hydrogels, detergents such as surfactants and poloxamers and their carriers, other superabsorbent-containing substances or mixtures of such substances, can be present in the absorbent core itself, for example, in such a way that the superabsorbent granules are incorporated into substances of this type, also in addition to other layers containing the superabsorbent particles or other osmotically active substances.

[0019] The incorporation of superabsorbent substances into hydrophilic fibers, which serve as a carrier substance, is disclosed. Within a covering of the inner layer, additional cover layers of other materials, such as cellulose, may be present. This product consists of superabsorbent substances, hydrophilic fibers, a cellulose cover layer, or a cover layer of hydrophilic fibers, and a covering within a second covering that additionally contains at least one of the aforementioned substances. This additional substance may also be present in this covering alone or adjacent to other substances in a further covering, so that the overall product comprises an interior space and two or more coverings. Intermediate layers may be arranged between these, which can be waterproof, vapor-tight, air-permeable, semi-permeable, or otherwise designed.

[0020] One way to ensure dimensional stability is to firmly press the aforementioned substances into the absorption body, which does not necessarily require adhesives.

[0021] This results in a product that incorporates substances such as CMC, hydrophilic fibers, alginates, or other materials in an encapsulated form. The purpose of this is to allow the more osmotically active substances, such as granular superabsorbent materials, to dry out other components of the dressing, thereby extending the lifespan and effectiveness of these materials and saving costs, material, and care time. Simultaneously, periods of wound rest are prolonged, stable wound temperatures, crucial for repair processes, are maintained, and a bilateral interaction occurs between the flat surfaces of the materials. On the one hand, these materials exert a beneficial effect on the wound area in the direction of the wound, while on the reverse side, facing away from the wound, they are dried out by other components of the dressing material.The substances applied closer to the wound thus exert their effect, and those on the opposite side can cause a flow-through flushing through them into the other parts of the dressing.

[0022] The superabsorbent substances, primarily granules, can be pressed or incorporated into fiber mats, but can also be glued, welded, or otherwise fixed in place. Here, two cover layers can encase a mixture of cellulose and superabsorbent substances, which are manufactured, for example, as airlaid mats. The superabsorbent substances can also be incorporated into all the other materials mentioned, especially hydrocolloid fibers, alginates, or a mixture of various substances of the type mentioned, or with other materials.

[0023] Two layers of cellulose with superabsorbent substances (without cellulose) in between, arranged in a sandwich configuration, are also conceivable.

[0024] Since changing a dressing causes the temperature of the wound area to drop, it is conceivable to add reagents to the absorbent material that maintain a stable wound temperature through a controlled, biocompatible, exothermic reaction. Chemical reactions such as pepper-based processes can be considered, especially since these will also create an additional osmotic suction.

[0025] The product can be used as part of compression therapy, as a dressing in the treatment of compartment syndrome, or in vacuum therapy using negative pressure. In the latter case, the two pressure types, subatmospheric and osmotic, are combined, resulting in a very effective edema therapy.

[0026] Known dressings containing superabsorbent particles fail to achieve the necessary potency for several reasons. These dressings contain too few superabsorbent substances, and their potency is further reduced by placing them far from the wound area behind polyurethane foams or cellulose layers. In other products, the osmotic effect is weakened with solutions. Overall, the superabsorbent particles applied in this way have very low osmotic potency, and their potential is depleted within the dressing.

[0027] The absorbent body comprising the mixture according to the invention is intended for use in acute and chronic wounds, iatrogenic skin transections, burns, weeping inflammatory skin conditions or ulcerating processes of neoplastic origin, weeping infections, fistulas, postoperative drains, stomas, atopically altered areas of the skin, skin folds near joints such as axillary or groin skin, mucous membrane surfaces of humans and animals, and in conjunction with other dressings that have a local therapeutic effect, as well as in other applications where an atraumatic wound dressing is indicated. Split-thickness skin graft donor sites, plastic reconstructions, abscesses, and urological applications are equally established as indications, as are proctological applications and prophylactic use for prevention, e.g., to contain the spread of germs and reduce their propagation.The functional combination with the other extensively described advantages is particularly important. Applications under atmospheric negative pressure, whether continuous or intermittent, electric or manual, as well as applications in compression therapy or carbon dioxide baths, represent further significant possibilities.

[0028] For a general understanding of the term "osmotically active", it should be noted that this refers to properties or sums of physical and / or chemical processes, such as electronegativities, molar masses, charge balance, molecular interactions or dilution tendencies of substances such as salts, sugars and proteins, which, due to their own properties or quantities and concentrations, cause a pressure gradient in the sense of a flow or suction tendency of, for example, aqueous substances.

[0029] Although the presence of a semipermeable membrane is necessary for the experimental demonstration, the underlying laws also take place at the molecular level without the membrane.

[0030] Laws and principles from the areas and topics of hypotonicity, isotonicity, and hypertonicity of individual components, diffusion, equalization processes and energies, equilibria, hydrostatic pressure, osmotic pressure, chemical potentials, mixing effects, concentrations, molar density, entropy, and Gibbs free energy can be applied individually or in aggregate. Alternatively or additionally, rule sets governing oncotic pressure processes, colloid osmotically relevant processes, and other events influenced by the number and / or properties of macromolecules may be used.

[0031] In simplified terms, processes that lead to interactions with water, directing it, storing it, or at least forming short-term connections with it are preferred here.

[0032] The significance of this definition of flow direction has far-reaching consequences. For example, two essential cleansing processes take place at the wound. First, the superabsorbent particles draw wound exudate from the wound bed, thereby supporting physiological normohydration (normal fluid content). The wound edges are stabilized, and the wound bed is positively conditioned. Second, excretions with low water content concentrate in front of the encapsulation material, adhere to it, and can be removed by replacing the used absorbent core.

[0033] The absorbent core comprising the mixture according to the invention counteracts undesirable granulation of the wound. Since the pathological exudate is absorbed, harmful proteases are also drawn up, including, for example, MMPs (matrix metalloproteases) and TIMPs (tissue-inhibiting metalloproteases). Due to the active absorption processes of the harmful proteases, a secondary anti-inflammatory effect is achieved. The absorbent core adapts to the morphology of the wound area via the absorption and swelling process.

[0034] The mat, locally saturated and swollen with wound fluid, fills the respective wound at least partially.

[0035] The mat can initially move freely within the covering.

[0036] Ideally, the swollen absorbent core should lie completely flat against the wound area. In this context, the outer layer facing away from the wound can consist of a textile or film material that is not, or only slightly, elastic, while the other layer, closer to the wound, is significantly more elastic.

[0037] The aim is to maximize the surface area of ​​the superabsorbent particles distributed within the core, as well as to achieve the greatest possible homogeneity of the core. The superabsorbent particles, preferably embedded without adhesives within the core, can form a substantially uniform matrix. The superabsorbent particles can have sharp edges to increase their surface area. These sharp edges also improve adhesion to the textile fibers, which are preferably processed into a randomly oriented or directional, mechanically bonded nonwoven fabric. The textile fibers can be bent, curved, or folded fiber sections of varying widths and lengths. The textile fibers can at least partially surround the individual superabsorbent particles, thus increasing the interfaces and consequently the absorbency. Suitable textile fibers include polymer fibers and natural fibers.The superabsorbent particles can be, for example, cross-linked, partially neutralized acrylic acid polymers. The superabsorbent particles can also be gel-like or ceramic.

[0038] The superabsorber particles may contain a core crosslinker, in this case as a core crosslinker (CXL) or as a surface crosslinker (SXL), or a mixture of both crosslinkers.

[0039] The absorbent body, with its superabsorbent particles, acts as a hydroactive wound dressing, allowing the absorbed fluid to evaporate again.

[0040] The applications of the absorbent material can be expanded by adding pharmacological substances at the atomic or elemental level, such as compounds containing zinc, calcium, or sodium. Examples of such pharmacological substances include anti-inflammatories, antibiotics, growth factors, homeopathic remedies, analgesics, antipyretics, and disinfectants.

[0041] The inner layer and / or the outer casing may contain extracts of brown algae, carboxymethylcellulose, alginates, hydrocapillaries, hydrogels, enzymes, ceramic-based compounds, growth factors, metallic additives (e.g., silver, gold, platinum, and titanium), and osmotically active substances such as salts, sugars, proteins, and enzymes like peroxidase to regulate osmotic pressure. The addition of antimicrobial agents such as octenidine or polyhexamide may also be included.

[0042] The pharmacological substances can be partially absorbed and dissolved by the body's own fluids, such as pathological wound exudate, without the use of electrolyte solution.

[0043] Thus, by reducing the number of germs through the physical properties of the dressing material, the risk of mutations, biofilms, resistances and infections is reduced, and the effectiveness of antibiotic measures is improved through pharmacological interventions.

[0044] For example, a suction effect directed towards the absorbent core is achieved with non-superficial exudate, altering both the amount and speed of drainage. The pathological tendency for particularly slow flow of wound fluids through the tissue, which can lead to fluid stasis deep within the tissue, results in cell edema and fluid overload in the intercellular space. The suction effect created by the external exudate shifts the fluid stasis towards the absorbent core, thus reducing fluid overload at the wound bed level and improving its overall nutritional status and healing potential.

[0045] Essentially, two cleansing processes are carried out at the wound. First, the superabsorbent particles draw wound exudate from the wound bed, thereby supporting physiological normohydration. The wound edges are stabilized, and the desired wound bed conditioning is achieved. Second, excretions with low water content concentrate in front of the encapsulation, adhere to the encapsulation material, and are removed when the used absorbent core is replaced. The absorbent core, comprising the mixture according to the invention, counteracts excessive granulation of the wound. Since the pathological exudate is absorbed, harmful proteases are also absorbed, including, for example, MMPs (matrix metalloproteases) and TIMPs (tissue-inhibiting metalloproteases). Due to the active absorption of the harmful proteases, a secondary anti-inflammatory effect is achieved.The absorbent body adapts to the morphology of the wound area through the absorption and swelling process.

[0046] Through the absorption process, the absorbent material can become so heavy that its own weight inhibits excessive granulation, thus contributing to wound bed homogenization. The weight-determining element is the wound exudate itself.

[0047] This results in a dressing material that, when viewed as a whole, has a homogeneous surface, but due to its technical design offers a general response specific to each wound phase.

[0048] In addition, necrotic areas of the wound are abraded and removed by the dressing material, whereby the subsequent wetting is absorbed by the dressing material.

[0049] Where a wound is infected, the absorbent pad draws in the germs and removes them, along with toxins, exudate, sources of inflammation, and edema. Since edema and parts of the inflammatory response promote the formation of organized bacterial systems called biofilms, the absorbent pad shortens the duration of the infection, reduces the likelihood of infection occurring, and works synergistically with other anti-infective measures. The development or proliferation of germs such as MRSA (methicillin-resistant Staphylococcus aureus) is combated. Particularly in outpatient, home-based, and non-hospital settings, the eradication of these population-threatening germs leads to rapid healing of chronic wounds, as this is the only place where they find the necessary pathogenic conditions and can cause potentially life-threatening, often uncontrollable infections. This also applies to germs such as VRE (vancomycin-resistant enterococci) and CA-MRSA (community-acquired MRSA).

[0050] Where a wound is in the cleansing phase, the absorbent core actively absorbs and binds the flushed-out fluids. Where a wound is granulating and new cells are forming, the absorbent core protects them from the pathological exudate from the surrounding wound area.

[0051] Where a wound hypergranulates, the absorptive tissue slows its growth to the desired rate through its own weight and the weight of the absorbed exudate. The wound edges are kept free of inflammatory edematous processes in the healthy skin.

[0052] Even where there is healthy tissue, the thinness of the absorbent core under compression bandages helps to prevent the bandage's transition edges from pressing too deeply into the patient's skin, whereas many other products are thicker and can cause constrictions, indentations, or persistent pressure edges, with the risk of reduced perfusion and thus promoting skin damage.

[0053] Compression from surrounding compression bandages is transmitted unimpeded, whereas, according to La Place's law, thicker bandages, even with the same compression environment, impede compression at greater depths due to a larger radius, resulting in less compression being transmitted, or even uncontrollably less compression being transmitted. This is particularly true for foam bandages and thick cellulose layers, as their elasticity further exacerbates this reduction.

[0054] The absorbent body comprising the mixture according to the invention can also be used for moist therapy without being wet beforehand.

[0055] At selected locations within the absorbent core or inner layer, a significantly higher quantity of comparatively small, rapidly absorbing superabsorbent particles may be present than at other locations, thus creating a local wound-filling function during the absorption process. If a wound-filling function is desired, a covering with walls of varying elasticity is advantageous. In particular, the wall closest to the wound can exhibit greater elasticity than the opposite wall furthest from the wound.

[0056] Furthermore, the absorption element can be backed by at least one layer of foam, which is connected to the casing via at least one adhesive point or a peripheral seam. The foam layer can be open- or closed-cell, hydrophilic or hydrophobic. If a closed-cell foam is used, it is recommended to incorporate through openings in the foam.

[0057] Incidentally, the through openings or holes can be incorporated into any flat material that is part of the absorption body.

[0058] The addition of surfactants can significantly increase wound exudation and may be desirable. In this case, biocompatible substances that are safe both systemically and locally should be used to avoid disrupting the complex cascade of interactions involving pressure, perfusion, venous drainage, cell metabolism, motility and inertness of cells such as erythrocytes and granulocytes, endogenous or added growth factors, immune-relevant cells and substances, and other factors important for tissue growth. A possible vasodilation in the wound area, even if it results from the addition of surfactants, can be beneficial, as the primary goal is to increase wound exudation and achieve deep cleansing of the wound area.This also applies to the visually recognizable wound floor, the causally therapeutically relevant wound base, and the wound edge, tissue parts that are protected from exudation and harmful substances by the superabsorbent granules or other wound contact surfaces, such as foams made of PU, PE or other polymers, cellulose, alginates, hydrogels, carbon compounds, silver preparations, honey, nonwovens, antiseptics, carriers of these substances, films or grease-impregnated surfaces fulfilling this function.

[0059] These additives, such as surfactants or other substances mentioned, can be covalently, soluble, or freely bonded to other surfaces.

[0060] Parts of the components can have different hole structures that facilitate the interaction of higher layers. This facilitates the passage of substances into the nearest layers in both directions, both adding to and drawing away from the wound.

[0061] In combination with a foam dressing in a shared additional cover, further advantages can be achieved. This allows for two forms of wound rest: In cases of heavy exudation, the side of the cover displaying the absorbent core is applied to the wound. Through the desired strong suction effect, the absorbent core relieves stress on the surrounding tissue by removing the unwanted pathological exudate containing harmful messenger substances and components. Interstitial and intercellular, as well as cellular and vascular spaces, achieve near-physiological irrigation, thus optimizing perfusion, arterial inflow, venous drainage, and transmembrane diffusion, preventing them from being hindered by long diffusion pathways, pathological aqueous solutions, and reactive biorelevant enzymes.Cell growth requires the arterial influx of proteins and oxygen, as well as the influx of blood vessels, nerves, and immune system components.

[0062] In cases of low exudate, the foam side of a foam dressing can be applied to the wound. Here, the absorbent core indirectly promotes wound healing by using its absorbency to dry the foam. For this to work, the foam must be nearly saturated with moisture so that, for example, capillary action allows blood to flow through the foam and gently into the absorbent core. The absorbent core then dries the foam, forming a secondary reservoir that increases the foam's capacity by the capacity of the absorbent core itself, without the latter having significant contact with the wound.

[0063] In this embodiment, a covering that surrounds the foam and the absorption body can be formed from perforated PE film having crater-shaped holes of the same or different geometry.

[0064] The principle of the single absorbent body makes it possible to carry out a simplified optical control of the emerging wound exudate when using such absorbent bodies impregnated with superabsorbent particles, provided that the absorbent body is used in the form of a corresponding size adapted to the wound.

[0065] A major advantage is that the absorbed wound exudate can occupy and maintain a limited position within the absorbent body, thus preventing the surrounding skin adjacent to the wound from being affected by the wound exudate.

[0066] To further clarify the general understanding of how this works, it's worth emphasizing that fluid overload, for example, represents an edema that develops as a result of chronic venous insufficiency (CVI). Due to pathological processes, the vessel wall of the affected vein becomes more permeable, and significant amounts of fluid initially contained within the vein leak out into the space outside the vein. This occurs particularly at the level of the ankle joint, as this is where the venous column originates and where hydrostatic pressure is highest.

[0067] This leads to overhydration of the surrounding tissue, including healthy cells, skin, and intercellular spaces. The diffusion of arterial and nutritionally important substances, as well as the removal of waste products via the veins, is impaired. The cells enter a reduced metabolic state, biorelevant processes and finely orchestrated metabolic cascades cease, and the cells die. A venous leg ulcer develops, penetrates to the skin, and remains overhydrated for life.

[0068] The same process in the lungs would be combated by increasing kidney function, at least if the entire lungs were affected.

[0069] Treating this fluid overload in the lower leg with diuretics is not indicated, as numerous medical reasons argue against it. This would involve interfering with cardio-relevant systems, and since there is no apparent acute danger to life, unlike in pulmonary edema, other approaches must be found.

[0070] In contrast to these findings, current therapy involves applying dressings with comparatively low absorbency and poor retention. The edema in the leg tissue is thus treated in a non-directional, passive, local, and physical manner.

[0071] Such therapeutic approaches have in common the combination of causal therapy (cardiac medication to strengthen the heart and therefore combat blood congestion in the lungs on the one hand, and wearing compression stockings to combat the leakage of venous fluid on the other) and symptom treatment (diuresis to drain the lungs on the one hand, and the application of supposedly highly absorbent dressings on the other).

[0072] While impaired function of, for example, lung tissue is considered threatening, edematous swelling of tissue near joints is often seen as transient and therefore unproblematic. This is where the first imbalance arises, which, while understandable in terms of vital functions and life preservation, underestimates the rapid path to patient suffering, pain, chronic illnesses, costs, sometimes even job loss, and a host of other disadvantages.

[0073] Every doctor knows that prescribed compression stockings are often not worn correctly or consistently. This demonstrates that their essential function—compressing leg tissue—doesn't fit into patients' daily lives, as putting them on, if even possible, is very difficult and perceived as very uncomfortable. In summer, patients sweat, and taking them off is often difficult as well.

[0074] As a result, either compression stockings are prescribed that generate too little pressure but are at least worn, or no stockings are worn at all. The causal therapeutic approach, which for the lungs involves increasing cardiac output with medication, often fails in the case of venous insufficiency, as this can only be achieved through effective compression therapy. If this therapy is not performed, or not performed ideally, the vein will continue to leak indefinitely.

[0075] Therapy using negative pressure systems, the so-called vacuum therapy, appears to be more effective, as it uses subatmospheric pressure conditions to draw fluids down to the depth of the leakage point.

[0076] However, since this choice of therapy also has a number of disadvantages, ranging from high costs and immobility to high application requirements and even deaths, it is necessary to find a third approach in addition to nephrological-diuretic and vacuum-assisted therapy approaches.

[0077] An easy-to-use dressing that utilizes known physical conditions and circumstances and avoids pharmacological processes would be advantageous.

[0078] In the present case, a composite comprising the inventive mixture is selected which achieves the advantages of subatmospheric approaches without having to contend with the disadvantages of negative air pressure, such as the creation of airtight and suction-tight chambers.

[0079] This is achieved through the use of significant osmotic negative pressure conditions, which are applied to the wound surface in the form of a dressing and follow physical laws in a novel way.

[0080] Preferably, the inner layer, which is in the form of a mat of cellulose carrier material for superabsorbent particles, has a basis mass of more than 300 g / m² and contains more than 50% osmotically active substances. The binding strength is 0.5 to 2 g of NaCl in a 0.9% solution per g of the inner layer.

[0081] The dressing thus creates such a high osmotic pressure (first force) in the wound that fluids from the wound surface are immediately absorbed. The cohesive forces of these fluids (second force) transfer this flow direction to adjacent wound fluids, creating a deep-penetrating effect. Within the wound, a flow direction for the excess wound fluids is therefore defined, and this is maintained and perpetuated by several other factors.

[0082] In addition to the cohesive tendency of fluids, their tendency to adhere (third force) must also be mentioned, so that although only a small amount of fluid experiences direct osmotic pressure, its directional influence is still present even at depth. It can be assumed that a mechanism (fourth force), arising from capillary ascent, also occurs between cells deep within the tissue, thus supporting the maintenance of the flow direction.

[0083] The pressure exerted deep within the vein (fifth force) reinforces this effect, as it only allows fluids to escape peripherally, towards the skin. This describes the fifth influencing factor, which, triggered by the high osmotic suction, leads to a reduction in the fluid buildup at the wound bed.

[0084] The sum of these factors leads to the sixth quantity. This is significant for the functioning of the interplay between the first five.

[0085] To explain this, some background information is necessary, as physical laws relating to flow are important for determining the prevailing forces: From a physical perspective, the cause of flow is always considered to be a pressure difference Ap along a section of a pipe system. While in our case there is no pipe system in the strict sense, the tissue through which the fluid flows can be considered a closed system through which the wound exudate must find its own paths and channels. In doing so, it is subject to braking influences such as shear forces, flow resistance, friction, mechanical pressure differences, shear stresses, current intensities, varying diameters of the paths and channels, and other influencing factors. Despite its slow flow rate, the conditions for classifying it as laminar flow are not met; conversely, the condition of a higher flow velocity for classifying it as turbulent flow is also not fulfilled.

[0086] Assuming that the Reynolds number Re, an empirical number that describes approximately a ratio between impulses (force impulses) and possible cushioning through friction, is below the limit of the transition height of 2300, it would be reasonable to assume that the conditions of a laminar flow are more likely to be present in untreated ulcers of the described origin.

[0087] There are certainly no constant laws regarding flow direction and flow velocity; rather, there are mixtures of different laws such as the Hagen-Poiseuille law or Bernoulli's law, or the influence of the Fahraeus-Lindquist effect (influence of vessel diameter, axial migration).

[0088] Following this rather purely physical consideration of flow conditions, it is important to note that in the untreated wound region there are a wide variety of phases, conditions, pressures and flow rates.

[0089] The five forces mentioned above then come into play. The osmotic potential of a superabsorbent breaks through this disorder and creates a flow direction for the wound fluid by drawing it away from the surface, thereby drawing out fluids from deeper wounds through the sum of the aforementioned forces. The momentum of the first water molecules entering the dressing generates momentum for all subsequent water molecules, as they are bound together in a chain-like fashion by the aforementioned forces, also known as van der Waals forces. The pull on the first link creates a pull on the last link, and in the sense of an independent, dynamic continuation of these processes, the water molecules permanently follow the initial flow, since the osmotic gradient of the superabsorbent creates a one-way street into the product.

[0090] The gradient of osmotic force and cohesion creates drainage deep within the tissue, directly in the vicinity of the insufficient vein. The dressing applied to the wound surface performs its primary function precisely at this tissue depth, drawing out water and dehydrating the edema. It achieves this by penetrating the tissue between the wound floor and the wound bed, absorbing perivenous excess fluid transtissively without being in close proximity to it. The high osmotic potential removes the non-superficial edema from the wound. Gently and without dehydrating cells or air, the amount of exudate flowing through these channels regulates the suction force. With high exudate volumes, the product actively engages and draws more readily towards the wound floor surface, while with low volumes, only humidity is generated through evaporation.In all cases, the principles of wet therapy are also granted and supported.

[0091] This creates an absorbent dressing that, under high osmotic pressure, gently and actively removes biorelevant substances such as germs, toxins, proteases, etc. Here, the pathological exudate is not seen as a problem to be controlled or as detrimental to wound healing, but rather as something that promotes healing: it forms the transport medium for this cleansing absorbent effect and, after entering the dressing, is released back into the wound as humidity, having been freed from its harmful substances, as these do not evaporate but remain in the dressing. The dressing thus cleanses parts of the exudate after it has carried its own and other harmful substances into the dressing.

[0092] It found its way into the dressing because it was stimulated to flow in a predefined direction. This dynamization of rather static water in the surgically accessible region and in the intercellular spaces leads to the formation of flow channels and thus to the relief of the perivenous tissue. In the course of this process, the pathological exudate becomes the irrigating solution for the wound surface and the wound depth, and the continuous flow keeps the flow channels open.

[0093] Unlike vacuum therapy, the maximum suction power is reduced locally and gradually over the course of the application. Therefore, it is not as static as an electronically set pump pressure and is thus less risky. The required absorbency of the dressing, achieved via the superabsorbent polymers, is determined by the amount of exudate present on the wound surface, resulting in wound-adapted suction control. Depending on the stage of wound healing and the condition of each square centimeter of the wound, a suction power is generated that is typical for the respective wound situation.

[0094] Furthermore, unlike vacuum therapy, the dressing eliminates the flushed-out germs and potentially infectious exudate directly after they emerge from deep within the body, and combats the germs immediately upon entering the dressing. The exudate is not drained and therefore does not pose a risk to staff. In some cases, endemic or epidemically relevant germs can only be disposed of as expensive and costly infectious liquid waste.

[0095] It is important to note that the desired effect requires a pressure of at least approximately 20 mmHg, as the suction is insufficient below this value in most cases. This negative pressure is created by the immediate proximity of the carrier of the osmotic potential to the wound bed via the thin covering.

[0096] This also highlights another significant difference compared to other dressing materials. When these dressings, especially those containing cellulose wadding, fluff pulp, or non-woven fabric, come into contact with exudates, they immediately lose their structural integrity and degenerate when saturated with moisture. Very soon after contact with exudate, these dressings become wet and lose their absorbency and tensile strength. Given the need for deep tissue absorption, the suitability of such a dressing for venous leg ulcers is questionable. Even though such conditions are treated with modern, hydroactive dressings like polyurethane foams, it's clear that insufficient progress has yet been made in this area.

[0097] Exudate and germs represent the weak point in the healing process. Exudate sustains germs, and germs lead to more exudate. Edema leads to a reduced immune response, and the cycle continues. Breaking this cycle allows the wound to heal and close.

[0098] This concept takes into account, in particular, that wounds are not homogeneous and uniform throughout. Many wounds experience all phases of wound healing simultaneously, being necrotic and dead in some areas, infected and coated in others, exuding and watery in some, fibrinous in others, and hypergranulating in still others. Here is the wound edge, there inflammation, here freshly epithelialized tissue, and there a bleeding lesion from the painful removal of stuck dressings.

[0099] The dressing described here allows for independent adaptation to the respective conditions, as it corresponds to each of the mentioned wound situations by providing the appropriate response at every point. It softens necrotic areas through atmospheric moisture and abrasion, absorbs germs along with the exudate from the regional inflammation, debris concentrates on the outer wall of the dressing and is removed when the dressing is taken off, aqueous exudate is absorbed with high retention capacity, hypergranulation is inhibited by the dressing's own weight and the weight of the absorbed exudate, fresh epithelium is protected from exudate, and adhesions do not occur; if they do, a standard wound contact layer can be used as a primary dressing.

[0100] All the typical advantages are further optimized by ensuring the dressing has full contact with the wound. It's important to consider that a wound surface isn't smooth like a pane of glass, but rather has an extremely heterogeneous morphology. From the perspective of a small cell, the comparison to an aerial photograph of Germany is quite apt: here in the south we have mountains, up there it's rather flat terrain, here in densely populated areas there are many tall buildings, and here are many lakes and perhaps even some areas slightly below sea level. The understanding that hardly any wound has only a single healing phase and healing state leads to the necessity of a dressing that adequately treats several phases simultaneously. This is guaranteed by the chosen technical approach.

[0101] It may be advisable to use one of the aforementioned foam dressings as a full-surface primary contact layer, provided the advantages of the absorbent core are also utilized. This could be achieved by having the foam in direct contact with the wound and the absorbent core placed directly on its reverse side. This ensures, firstly, that the foam adapts to a highly inhomogeneous wound bed morphology, acting as a flow and contact layer to direct wound fluids directly into the absorbent core. This function can also be fulfilled using alginates, charcoal dressings, or cotton and non-woven fabrics.

[0102] When polyurethane foams are used, they tend to curl up at the edges. The use of the absorption layer on the back provides a desirable mechanical counter-pressure, thus helping to maintain a full contact surface.

[0103] The outer shape of the bandage can be in the form of squares or other geometries, but it can also have anatomical shapes such as gloves for the treatment of extremities, for example.

[0104] In all cases, a new understanding of wound care, edema therapy, and vascular insufficiency treatment is of central importance. This involves dynamizing venous fluid, edema, and its associated fluids and directing them to the skin surface for forceful drainage, thus enabling wound closure. Stress reduction, swelling reduction, drainage, and the removal of harmful substances lead to a calming, deep relief, and decongestion of the tissue, which is cleansed through this irrigation process from the deep perivenous tissue down to the wound bed.

[0105] This new understanding also includes the possibility of combining it with vacuum therapy to achieve an increase in suction power. Modulations made possible by reducing the air suction power are conceivable, since osmotic suction forces are added and therefore allow for regulation of synergistic factors.

[0106] In all cases, with and without vacuum, exudation and pollution carried into the absorption body via the rinsing process are collected.

[0107] Synergistic factors can also be mutually dependent, for example in cases where exudation is stimulated and increased by surfactants, the use of the absorbent is necessary to control the resulting exudation.

[0108] Other additives can also be natural substances, for example extracts from fruits or nuts; in particular, saponins and extracts of soap nuts should be mentioned here: fruits of the soap nut tree (Sapindus mukorossi).

[0109] The swelling agents can reduce the number of germs in the wound area via ion exchange processes by inhibiting depolarization and its propagation, or by reducing concentration gradients across the cell membrane of organisms or germs. Here, combating resistant germs can play an endemic or epidemic role, because the colonized wound often sustains the germ, and the germ often sustains the wound. Breaking this cycle is a significant measure in containing the spread of germs and their infections.

[0110] Here, the possibility of embedding the superabsorbent granules in a bed of cut and folded cellulose fibers before they swell plays a significant role in generating humidity in the wound area, as this maximizes the surface area achieved. The cellulose covering layers, the large surface area of ​​the granules, and the fibers combined provide ample space and surface area for the evaporation of absorbed liquids, thus creating and maintaining the desired moist wound environment.

[0111] This form of an inner layer as a superabsorber carrier can be found particularly in airlaid mats.

[0112] Non-systemic, local, but necessary drainage is therefore carried out via an exudate-loving dressing with high osmotic potency. This is because it is not obvious that a vein is diseased and that skin and connective tissue would simply perish as a result.

[0113] Only through these rinsing processes is it conceivable to bring impurities, residues of germs, cell debris, metabolic products of bacteria and cells located in the wound area to the surface in order to suction them up directly and remove them in a controlled manner.

[0114] The advantage is that, in addition to excess wound fluids, substances that impair wound healing are also removed and can remain in the patient's tissue for a shorter time. The consequences of pathological processes can be reduced.

[0115] According to one embodiment, the inner layer contains more than 40% osmotically active substances, based on the total weight. Osmotically active substances can also be present in the outer layer.

[0116] The osmotically active substances can be in powder or granular form, whereby the granular form can have both regular spherical or prismatic shapes as well as irregular shapes, such as a sand grain shape.

[0117] The inner layer can be designed to hold liquids whose specific gravity is approximately that of water, i.e., a value of 1.00, or slightly exceeds that specific gravity and is around 1.020, with a design also possible for higher viscous liquids whose specific gravity can reach, for example, a value of 3.00.

[0118] The osmotically active substances include primarily so-called superabsorbents; however, the inner layer may also contain other osmotically active substances such as salts, sugars, proteins, electrolytes, etc.

[0119] The aforementioned osmotically active substances may also be part of the coating. Furthermore, the coating may contain antimicrobial, odor-inhibiting, disinfectant, fungicidal, or other wound-healing substances, such as pharmaceuticals.

[0120] The specified concentration of osmotically active substances, utilizing the adhesive or cohesive forces of water, contributes to the regulation of fluid overload in deeper, non-surface healthy or pathological tissue. The osmotically effective pressure gradients are primarily achieved through ion exchange processes.

[0121] The over-dimensioning of swelling agents, especially superabsorbent particles, contributes to the fact that wound exudate, as well as solid particles and germs from the wound bed, can be carried along with it.

[0122] The composition of the absorbent body, comprising the mixture according to the invention, influences the flow direction of wound fluids via concentration gradients, slopes, and differences compared to the wound area. The suction generated by the absorbent body, which grows towards the skin surface, channels the wound fluids, accelerates their transport, and leads to the local fixation of tissue- and growth-damaging proteases and factors on the inner layer, thereby more effectively protecting the wound tissue, the wound edge tissue, and the wound region.

[0123] The potency of the osmotically active substance can be selected such that the extent of a local increase in hydrostatic pressure due to increased vascular permeability is counteracted by an effective osmotic pressure gradient. This gradient regulates tissue fluid overload between the two opposing centers through a defined flow direction and velocity, so that functionally, the sum of hydrostatic overpressure and osmotic suction leads to a reduced accumulation of fluid in the interstitial space. The osmotic potency of the absorbent can also regulate cellular fluid overload.

[0124] The potency of the osmotically active substance of the absorption body can be chosen such that the extent of local capillary hypertension is counteracted by a proportional osmotic suction effect, which shortens the retention of fluid in unphysiological quantities towards physiological hydration.

[0125] Furthermore, the inner layer or the outer covering can serve as a depot for medications or solutions that can be continuously released to the wound area.

[0126] The inner layer can consist of a mixture of superabsorbent polymers with cellulose as a carrier material, as well as two planar cover layers. At least one of the cover layers can consist of cellulose, whereby the density of the cover layer can differ from that of the carrier material.

[0127] The inner layer may contain additives based on acrylic acid or activated carbon. The absorption capacity of the absorbent core may exceed a value of approximately 95 g / 100 cm³, as measured according to DIN EN ISO 53923.

[0128] The absorbent core can contain starch polymers at least at one point, as these have a particularly hydrophilic character. Examples of suitable starch polymers include native starch polymers based on corn, potatoes, or rice, which are highly sensitive to moisture.

[0129] The absorbent pad can be coolable and, at least partially pre-saturated with liquids, applied in frozen form to acute wounds, sutures, or other skin areas. The liquids can be antimicrobial agents, hyaluronic acid, or other substances that promote wound healing, such as quaternary ammonium salts.

[0130] The absorption material can be placed on body surfaces that have an applied electric field. Direct current is particularly preferred. Microbial substances resulting from fermentation processes can also be added.

[0131] One of the effective substances can be a compound that promotes the formation of molecular networks. This can occur particularly in hydrophilic processes when links with water molecules are formed and the storage bodies possess cross-links.

[0132] The technical approaches to hydrophilic processes can be based on fundamental physical principles, such as the striving for balance and harmony. Entropy-driven processes, enthalpy, Brownian motion, and the exploitation of rarefaction tendencies can be key factors. The reduction of electrostatic interactions can also be a primary focus.

[0133] The absorbent body can contain a substance that is partially or completely surrounded by at least partially liquid-permeable silicone coatings. This can be an airlaid-type mat that does not use pure cellulose as a carrier material for the superabsorbent particles, but rather carboxymethylcellulose (CMC). Here, for example, a mixture of superabsorbent particles with carboxymethylcellulose is subject to a possible coating with a thin cellulose layer; this coating may be present on several surfaces or entirely absent. This embodiment is particularly advantageous because the cellulose incorporated in the classic mat is highly compressed and can be perceived as hard and potentially damaging, while the carboxymethylcellulose fibers may remain softer. Instead of, or mixed with, these fibers, other substances such as alginates or other substances mentioned here may be added.The swelling process can partially penetrate any existing coverings and have direct contact with the wound surface.

[0134] Inhomogeneous carrier substances for superabsorbent particles can be present in at least one layer of the absorbent material to provide the layer or mat not only with storage capacity but also with additional functions such as temperature maintenance, wound bed adaptation, or bacterial reduction. For example, silver preparations or polyhexanide and activated carbon can be combined here. The polyhexanides can be in dried form, liquid form, or bound to parts of the absorbent material.

[0135] The absorbent body can be inserted into body openings, folds, elevations or other cavities of the patient's body, where it can be used in particular to heal ulcers and tissue defects, for example during dental surgical procedures in the oral cavity.

[0136] The inner layer can be 3% to 90% smaller in area than the outer layer, which is an area of ​​the outer layer bounded by the circumferential seam.

[0137] Preferably, the covering consists of a woven or nonwoven fabric weighing at least 20 grams per m². The covering can be made of woven or nonwoven synthetic fibers, such as polypropylene or polyethylene fibers, natural fibers, or a mixture of natural and synthetic fibers. The covering can be permeable to both liquid and viscous substances.

[0138] The covering can consist of one folded sheet or of two sheets joined at their periphery, with the connection between the sheets being made by ultrasound, gluing, sewing, or similar thermal, physical, or chemical processes. Furthermore, the covering can have soft edges at its periphery, for example, resulting from extending the covering material beyond the seam.

[0139] The coating can have pores or meshes that are smaller than the dimensions of the substances to be absorbed in granular or powder form. The pores or meshes can also be larger, preferably slightly larger, than the superabsorbent particles if the latter are embedded in the carrier material of the inner layer or are present there in an adhesive dispersion that has dried out due to use of the absorbent body.

[0140] The dressing serves several functions. Although a technically simple polypropylene nonwoven fabric may be used, it fulfills many functions by allowing water vapor to pass through to the outside after it has entered the absorbent core as liquid exudate. To prevent tissue and vessel ingrowth, it has perforations or pores of a size chosen to prevent the wound's granulation tissue, particularly at the wound edges, from growing into the dressing. For example, the perforations or pores around the circumference of the dressing may be smaller than those in the rest of the dressing area.

[0141] The outer covering can be made of natural materials, such as cotton or silk fabric, or of perforated plastic film or fabric. The covering surrounding the mat can be partially or entirely made of a so-called wound contact layer, with the orientation of its smooth or rough side depending on the specific purpose. The smooth side protects the wound from irritation and unwanted influences of a secondary dressing. A rough surface, on the other hand, appears to move with the wound and creates a desired chemotactic stimulus for tissue regeneration.

[0142] The casing with the mat inside and the foam layer can be arranged within an outer liquid-permeable casing.

[0143] Finally, the wrapping material can be designed to be adhesive, so that viscous, sticky, cross-linked or particulate substances adhere to the wrapping and are transported out of the wound when the absorbent body is changed.

[0144] The absorbent body comprising the mixture according to the invention can be used universally for different wound therapies (ulcus cruris, cuts, abrasions, inflammatory wounds, burns, etc.), wound healing phases, and for use in collection devices such as drainage, stoma, fistula or other collection bags.

[0145] Below are some selected uses: as a dressing for treating an edematous or inflamed wound area; as a dressing for treating a microbiologically contaminated wound surface by using absorbency to trap, dehydrate, or draw germs or cell debris into anaerobic areas of the swollen absorbent core; as a dressing for removing inflammatory cytokines, metrix metalloproteinases, TIMPs, degraded fibronectin (which constricts tissue), or other substances that contribute to chronicity; as a dressing material for combination with sponge-like, for example, open-pore wound dressings; as a dressing for regulating humidity, as the absorbent core releases the aqueous components back into the air via their vapor pressure; as a dressing over a primarily applied wound contact layer or gauze as a secondary dressing without direct, surface-level contact with the wound;as a dressing beneath a waterproof film that fixes the absorbent core to the patient; as a dressing beneath a vapor-permeable film to achieve a breathable dressing; as a dressing for chronic venous insufficiency (CVI) with a secondarily exuding wound to provide compression via the swelling process of the leakage from the affected vessel; as an application in wound treatment that exhibits at least temporarily subatmospheric air pressure conditions.

[0146] Exemplary embodiments of the invention are explained with reference to the drawing. The figures show: Figures 1a and 1b show a schematic representation of an absorbent body comprising the mixture according to the invention, used in the treatment of leg ulcers; Fig. 2 shows pressure and suction diagrams related to the wound situation according to Fig.1 ; Fig. 3 a second absorption body comprising the mixture according to the invention, with an additional inner layer, in a perspective view; Fig. 4 a section AA according to Fig. 3 ; Fig. 5 another absorption body with two inner layers, in a schematic section; Fig. 6 an absorption body with an additional inner coating, in a schematic section; and Fig. 7 another absorption body, with a hydrophilic inner layer of carboxymethylcellulose, also in a schematic section.

[0147] The Figuren 1a and 1bFigure 1 schematically shows a cross-sectional view of an absorption body 100, consisting of a liquid-absorbing inner layer 1 and a liquid-permeable, perforated outer layer 2. The inner layer 1 comprises a cellulose-like carrier material 3 and two planar, also cellulose-like, cover layers 4.1, 4.2, wherein only the core, i.e., the carrier material 3, is permeated with osmotically active, superabsorbent polymers in the form of superabsorbent particles 20. The cover layers 4.1, 4.2 are bonded to the carrier material 3 without adhesive; that is, the planar connection was achieved by compression.

[0148] The covering 2, formed from polypropylene fibers, has two congruent, liquid-permeable, rectangular sheets 2.1, 2.2, which are joined to each other at their edges by an ultrasonic seam 6 such that the layer 1 inside the covering, when dry, occupies an area bounded by the seam that corresponds to approximately 75% of the area of ​​sheet 2.1, 2.2 (see Fig. 1a). Furthermore, the covering 2 has soft edges 7 at its periphery, which are formed by extending the covering material beyond the seam area.

[0149] Although the cellulose-like material of the inner layer 1 is liquid-absorbent, satisfactory results are only achieved when this material is mixed with superabsorbent particles 20 using an empirically determined method. Accordingly, the nonwoven carrier material 3 was filled, laid, and prepared such that, together with the powdered and granular superabsorbent particles 20 contained therein, it had a basis mass of approximately 430 g / m², with the proportion of superabsorbent particles 20 in the carrier material 3 being 54 wt%.

[0150] As in Fig. 1b As shown, the absorbent body 100, initially placed dry on a wound (ulcus cruris) in the wound bed, swells after direct contact with the wound fluid. Through its function of absorbing wound fluid, it interacts with the wound bed by storing the wound exudate, releasing evaporated water, exchanging ions, and thereby reaching a weight that controls the extent of granulation in the wound bed.

[0151] The absorbent core separates the wound exudate entering it and releases portions of it, maximizing its surface area (droplets of atmospheric moisture). The inner layer 1 changes its thickness according to the local suction conditions caused by osmotic pressure.

[0152] The Fig. 2 shows pressure and suction diagrams that roughly correspond to the wound situation Fig. 1b This corresponds to the following: In venous area 10, the pressure is at its maximum and decreases towards the wound. Conversely, the suction is minimal in the venous area and increases to its maximum in the wound area. The suction arrows 9 indicate the channeled flow direction of the wound exudate.

[0153] The absorbed liquid does not flow back. The used, swollen absorbent body 100 can be disposed of along with any adhering particles.

[0154] Figuren 3 und 4 show a two-layer absorption body 200, in which the encapsulation 2 is, except for the one in Fig. 1a The first layer 1, which is permeated with superabsorbent particles 20, is surrounded by an additional layer 5 consisting of carboxymethylcellulose fibers. Since the absorbent body 200, together with layer 5, can be inserted into the respective wound, several through openings 8 are provided in layer 5 to allow wound fluids to be transported towards the second, cellulose-like layer 1. The openings 8 have a diameter of approximately 3 to 4 mm.

[0155] A little bit of the in Fig.4 A different embodiment (absorption body 300) is described in Fig. 5 The superabsorbent particles 20 are scattered between the two inner layers 1 and 5 in a medically safe, dried adhesive dispersion, which dissolves upon moistening with wound exudate. The adhesive dispersion can optionally be enriched with the aforementioned substances that promote wound healing.

[0156] Furthermore, in Fig. 6 An absorbent body 400 is shown, which, in addition to the outer layer 2, has a second, inner layer 7. Both layers 2 and 7 are fluid-permeable. Between the inner layer 7 and an inner surface 9 of the outer layer 2 lies the perforated layer 5, consisting of carboxymethylcellulose fibers. The inner layer 7 surrounds the first layer 1, which is permeated with superabsorbent particles 20. The absorbent body 400, with its perforated layer 5, can also be applied directly to the wound.

[0157] Finally, the Fig. 7 to remove an absorbent body 500, consisting of the fluid-permeable outer layer 2 and a hydrophilic inner layer 1 made of carboxymethylcellulose 1, which is additionally permeated with superabsorbent particles 20. The outer layer 2 consists of a perforated, wound-friendly film material, which is available on the market, for example, under the brand name Tredegar and which can be used to manufacture so-called wound contact layers. Optionally, the inner layer 1 can be perforated and, if necessary, covered with at least one top layer, as is the case with the Fig. 1a has been described, provided.

Claims

1. Mixture of a quantity of strongly osmotically active substances prepared on the basis of acrylic acid and a quantity of osmotically comparatively weak or osmotically inactive substances, for use in a method for treating chronic wounds, edema therapy or treating leg ulcers, in order to take up harmful proteinases, wherein the mixture is present in an inner layer (1) which substantially consists of the mixture, wherein the inner layer (1) is enclosed by an outer covering (2) which is permeable to liquids, wherein the inner layer (1) and the outer covering (2) form an absorbent body for applying to human or animal skin surfaces in the region of wounds, wherein the inner layer (1) is filled with osmotically active substances in such a way that an osmotic pressure can be exerted on a wound having the wound exudates contained therein, by means of which osmotic pressure the wound exudate can be drawn away from the organism to be treated and interstitial normohydration of tissue can thus be supported both in the superficial wound region and in the tissue depth, by directing body fluids into the absorbent body in the flow direction thereof towards the skin surface of the patient, and and wherein the inner layer (1) is structured such that the area density is at least 420 g / m2 and wherein the area density of the proportion of the osmotically active substances uniformly distributed therein is at least 200 g / m2.

2. Mixture according to claim 1, wherein the inner layer (1) consists of more than 40 wt.% of osmotically active substances, based on the total weight of the inner layer (1).

3. Mixture according to any of claims 1 or 2, characterized in that the application comprises the use in iatrogenic skin transections, burn wounds, weeping inflammatory processes of the skin or ulcerating processes of neoplastic origin, weeping infections, fistulas.

4. Mixture according to any of the preceding claims, characterized in that the absorbent body is used as a dressing as part of compression therapy, as part of therapy for compartment syndrome or in vacuum therapy.

5. Mixture according to any of the preceding claims, characterized in that the osmotically comparatively weak or osmotically inactive substance is cellulose.

6. Mixture according to any of the preceding claims, characterized in that the osmotically active substances are in powdered or granular form.

7. Mixture according to any of the preceding claims, characterized in that the covering (2) consists of two sheets (2.1, 2.2) which are connected together at the periphery thereof.

8. Mixture according to any of the preceding claims, characterized in that the covering (2) has pores which are each smaller than the dimensions of the granular or powdered substances to be absorbed.

9. Mixture according to any of the preceding claims, characterized in that the covering (2) adheres to viscous, sticky, cross-linked or corpuscular substances which can therefore be extracted from the wound when the absorbent body is changed.

10. Mixture according to any of the preceding claims, characterized in that the inner layer (1) is formed from an intermediate layer consisting of a mixture of superabsorbent polymers having cellulose as a carrier material (3), and from two planar cover layers (4.1, 4.2).

11. Mixture according to any of the preceding claims, characterized in that the inner layer (1) consists of hydrophilic fibers, such as carboxymethylcellulose fibers, and superabsorbent polymers with or without cellulose.

12. Mixture according to any of the preceding claims, characterized in that the inner layer (1) is composed in such a way that, when the absorbent body is placed on the wound, the re-release of fluid occurs only in the saturation region.

13. Mixture according to any of the preceding claims, characterized in that tissue- and growth-damaging proteinases and factors transported via wound exudates can be locally fixed by means of the inner layer (1).

14. Mixture according to any of the preceding claims, characterized in that the proteinases are matrix metalloproteinases or TIMPs (tissue inhibiting metalloproteinases).