RU2005493C1 - Bandage for treatment of pyo-septic and infected wounds - Google Patents

Abstract

FIELD: medical engineering. SUBSTANCE: bandage comprising a layer of hydrophilic permeable carbon-containing fabric is distinguished from currently known ones in that it is made of graphitized viscose fabric with a specific area of 3-4.5 m²/g. Possessing a low sorption ability, this fabric prevents changes in the composition of liquid discharge and precipitation of fibrin. Therefore, this bandage retains permeability for wound discharge and medicaments for a long time without interfering with aeration of the wound. EFFECT: higher curative efficiency and accelerated healing of infected and pyo-septic wounds.

Description

 The invention relates to medical equipment and can be used in the treatment of purulent-septic and sluggish wounds.

 Known means for the protection of open injuries of the skin and bone tissue, made in the form of a hard shell in the form of a damaged organ (in particular, in the form of sections of the cranial vault) based on carbon tissue.

 Such funds are intended to temporarily compensate for the lost function of bone tissue and the skull and to protect the open wound from contamination and mechanical injuries. They cannot be used to heal infected wounds due to their stiffness and shape of the skull.

 Dressings using carbon-containing tissue are also known that are applied to an infected wound.

 The disadvantage of this dressing is its high sorption ability. Adsorption on the surface of such tissue is characterized by high selectivity, therefore, in the wound layer adjacent to the dressing, the ratio between the components of the fluid released from the wound is violated. As a result of this, a dense layer of fibrin occurs on the surface of the wound, in the capillaries between the fibers and the internodes of the tissue. This prevents the removal of purulent secretions from the wound, injured blood cells and lymph, the aeration of the wound surface and its thermal regime are sharply reduced. Therefore, during the treatment process, a partial replacement of the dressing is required, which is undesirable due to significant injuries to the wound and the growth of wound infection.

 It was found that this drawback can be completely eliminated by removing the liquid wound discharge without changing their composition, increasing their viscosity, forming a dense sub-dressing scab.

 The aim of the invention is to increase the effectiveness of treatment and accelerate the healing of infected and purulent wounds by eliminating the loss of a fibrin layer dressing on the surface of the wound and capillaries.

The goal is achieved in that the dressing for the treatment of purulent, septic and trophic wounds, containing a layer of hydrophilic permeable carbon-containing tissue, is made of graphitized viscose fabric having a specific surface (determined by the method of low-temperature nitrogen adsorption using the Brunauer, Emmett, Teller (BET) 3-4 isotherm , 5 m ² / g and a contact angle (θ) of water and aqueous solutions of not more than 10 ^about .

Intervals of values of S _beats. 3-4.5 m ² / g correspond to experimental tests. Tissues with a specific surface area of less than 3 m ³ / g are characterized by increased stiffness, poorly adhere to the wound surface of a complex relief, and after removal of such a lot of small fragments of fibers, which leads to mechanical irritation of the tissues. Fabrics with S _beats > 4.5 m ² / g hydrophilize worse, on the wound surface they show less permeability to exudate, increase the healing time of wounds.

The differences in the specific surface area values are associated with the final temperature of tissue processing during graphitization, with the composition of the atmosphere in the graphitization furnace and, ultimately, with the degree of graphitization of the fabric itself and with the surface properties of its fibers. Outside the indicated intervals of values of S _beats. negative phenomena in tissue behavior increase significantly. At values of S _beats . <3 m ³ / g the wettability of the tissue flap with distilled water and aqueous solutions is deteriorating. On tissues with S _beats. > 4.5 m ² / g due to adsorption, fibrin deposition is noticeable and permeability decreases for liquid discharge by its amount in the drainage layer.

A tissue whose specific surface values lie in the range of 3-4.5 m ² / g has a low sorption capacity, as a result of which there is no change in the composition of the wound fluid in contact with the tissue surface, and fibrin does not precipitate. Therefore, the bandage for a long time (up to several days) retains permeability for both the wound discharge and for medicinal preparations, and does not prevent the aeration of wound tissue. In addition, the dressing does not stick to the wound and, if necessary, is painlessly removed, which indicates its high non-invasiveness, which is 2.5-7 times higher than that for medical gauze.

The experimental determination on individual fibers shows a change in the contact angle of 0-10 ^about . By increasing the contact angle of more than 10 ^{of the} observed deterioration of the therapeutic properties of the fabric: less exudate is removed in the area of the drainage material terms of rehabilitation of patients are extended for 7-10 days.

The dressing is made of viscose graphite at 2000-2200 ^о С hydrophobic fabric with an initial specific surface area of 1-3 m ² / g. To improve wettability and remove impurities, the original tissue is washed in a bath of water containing 0.5 wt. % NH ₄ OH and 0,25% J ₅ O ₂ at 30-60 ° ^C. During the washing solution is passed through a constant electric current connecting carbon cloth as the anode.

 Washing the tissue in the indicated electrolyte frees the surface of its constituent fibers from mechanical impurities in the form of dispersed particles and fragments of the fiber itself, water-soluble impurities are intensively removed. The application of direct current in this process significantly improves cleaning. Simultaneously with cleaning the surface of the fibers of graphitized tissue, its high hydrophilicity is formed, which is so necessary in conditions of subsequent medical use.

The hydrophilicity value of the treated graphitized tissue is determined by the speed and limit value of the capillary rise of distilled water along the vertically suspended tape of the test sample, as well as by the weight of the water absorbed by the fabric. As shown by physical, mechanical and analytical studies, the optimum mode for hydrophilization (activation) of graphitized tissue is a voltage of 70-90 V between it and a stainless steel cathode at a current density of 0.3-0.5 A / dm ² . The tissue processing time is 6-8 minutes at a bath temperature of 30-60 ° ^C. After treatment, on the surface of the fabric fibers found carboxyl, carbonyl, lactone and the phenolic groups in small quantities, causing the high hydrophilicity of tissue. The specific surface of hydrophilic tissue lies in the range of 3-4.5 m ² / g.

 The process described above is distinguished by the simplicity of technical design, low cost and environmental safety. The raw material for the production of carbon fabric for medical use is the large-scale, non-deficient technical graphite fabric. Graphitized carbon cloth wipes, being sterilized and packaged in airtight containers, certainly retain layers of healing qualities for five to seven years (direct observation). These napkins or fabric cloth can be combined arbitrarily with any draining, sorbing and coating materials of dressings, any combination of drugs used in solutions used by antiseptics, without making any changes to them, since an aqueous extract from such fabric invariably has pH = 7.

After drying, the BET specific surface area of the fabric remains in the range of 3-4.5 m ² / g. Before use, the tissue is sterilized by boiling in distilled water for 45 minutes.

 In order to prevent infection of wounds, the tissue after cooling is applied to a wound surface previously treated with hydrogen peroxide, chlorhexidine or antibiotics and fixed with a cotton-gauze dressing. A graphite viscose dressing can remain unchanged for several days, depending on its contamination.

 In order to treat purulent wounds after a necroectomy, opening the sagging, the wound is treated with a solution of furatsilina, chlorhexidine and antibiotics, and the tissue is applied to the wound. On the opposite side, it is recommended to apply a draining sorbent, or a cotton-gauze layer, which changes as the wound is soaked. A dressing made of carbon tissue can be on the wound surface of a purulent wound for three to five days continuously. With viscous discharge from the wound, proteolytic enzymes are added if necessary. In some cases, to enhance the antibacterial and detoxification effect, it is advisable to use various drugs by the endolymphatic route: broad-spectrum antibiotics, antiseptics (dioxidine, metrogyl), neohaemodesis and antiplatelet agents.

 The morphological characteristics of wound healing on the example of burns (provided they are closed with hydrophilic carbon wipes) differ significantly from those for ordinary gauze dressings with Vishnevsky ointment.

 On the 7-8th day from the moment of burn of the III B degree with the formation of a dense coagulation scab (removed on the fifth day by a combined chemical-surgical necroectomy with subsequent dressing), the wound is covered with a thin transparent secondary scab, the edges of the wound are even without noticeable edema. The control wound is characterized by an uneven contour larger than the original, swelling with areas of necrosis and bleeding on the surface of the secondary scab.

 Histologically, the wound bottom under a carbon dressing on the seventh day was covered with a continuous layer of granulation tissue with sharp plethora of capillaries. Young granulation tissue contains fibroblasts, a few leukocytes, lymphoid elements. Under granulation is a weakly edematous connective tissue with foci of collagen formation.

 In the control, the bottom of the wound is formed by a thin layer of granulations densely infiltrated by polynuclear cells, everything is covered with a layer of detritus, fibrin with numerous white blood cells. The underlying connective tissue is sharply edematous with foci of hemorrhage, in some places foci of destruction and myolysis of muscle fibers are noted. Starting from the tenth day, the size of the wounds on which carbon napkins were used are reduced due to the active epithelization of peripheral zones. Complete healing occurs on the 30-37th day.

 In the control, a wet wound with bleeding coarse granulations, covered with white coating, showed the onset of epithelization only on the 20th-25th day with constant foci of necrosis, chronic inflammation. This led in the final stage to the formation of a rough post-burn scar.

 Thus, it is stated that when the burn wounds were closed with a hydrophilic carbon napkin with a standard drainage layer (cotton wool, canvas, non-threading hygroscopic felt, etc.), the inflammatory reactions quickly subsided. The wounds did not contain purulent discharge, uncomplicated granulation and epithelization of their surface with the formation of a gentle soft scar actively proceeded. The terms of treatment were reduced by 30-45%. With early closure of wounds with hydrophilic carbon tissue, the local use of potent antimicrobial drugs and drugs was significantly reduced. The overall comfort of patients sharply increased. All this applies equally to the observed processes and results of treatment of wounds of various origins and accompanied by wound infection. The contact of the wound surface with hydrophilized carbon tissue significantly intensifies all the regenerative, regenerative reactions of living body tissues.

PRI me R. A carbon cloth dressing (S _beats = 3 m ² / g, θ = 0 ^о ) was used to treat purulent wounds of patients suffering from osteomyelitis. The tissue was tightly attached to the wounds on parts of the body with different reliefs, did not cause skin irritation and itching, did not have an allergenic and locally irritating effect on the wound and skin, and was removed painlessly. After the first or second day from the moment of application of the tissue, the inflammatory phenomena subsided. The wound was cleansed of purulent contents. After 3-4 days, live granulation and marginal epithelization of wounds appeared. The use of the dressing made it possible to quickly eliminate inflammation, cleanse the wound from purulent discharge, significantly accelerate the granulation process, which contributed to the rapid epithelization of the wound. The cure period, in comparison with the known method, was reduced by half. PRI me R 2. A bandage made of carbon tissue (S _beats. = 4.3 m ² / g, θ = 10 ^about ) was used in the treatment of burn wounds in severe and extremely severe patients. After treating the burn wound with hydrogen peroxide with the addition of antiseptics and drying the wound with gauze napkins, the tissue was applied to the burn wounds, fixed with a gauze or mesh bandage. The tissue is well modeled on burn wounds, repeating their configuration, does not dry to the wound surface, freely separates from it during dressings, without causing additional injury to the wound itself and the skin surrounding it. At the same time, the tissue has significant capillary activity, well removing wound and contributing to the purification of the wound from purulent exudate. Under the influence of the application, a decrease in the intoxication of the patient’s organism and a significant decrease in the microbial contamination of burn wounds were noted. There was a positive effect on the healing of subdermal burns of grade III A at the optimal time and a reduction in the preparation time of burn wounds for autodermoplasty surgery.

PRI me R 3. The intracavitary application of carbon hydrophilic tissue (S _beats = 3.5 m ² g, θ = 7 ^o ) in the form of tampons in the treatment of patients with peritonitis contributed to the reduction of mortality, complications and the average duration of the disease. (56) Patent of England N 2206495, cl. A 61 F 13/00, 1989.

Claims (1)

Dressing for the treatment of purulent-septic and infected wounds containing a layer of hydrophilic permeable carbon-containing tissue, characterized in that, in order to increase the effectiveness of treatment and accelerate healing of infected and purulent wounds by eliminating fibrin on the surface of the wound, it is made of graphitized viscose tissue having specific surface area 3 - 4.5 m ² / g, and the angle of wetting with water and aqueous solutions of not more than 10 ^o .