RU2257918C2 - Medical open-pore sorption material and articles based thereof - Google Patents

Abstract

FIELD: medical-destination absorption materials.

SUBSTANCE: invention relates to medical open-pore sorption nonwoven materials and articles based thereof, in particular to bandaging and draining articles etc. The articles can be used in ophthalmology, microsurgery, general, cardiovascular, and dentofacial surgery, gynecology, stomatology, otolaryngology, and other areas of applied medicine. More specifically, invention provides open-pore sorption material based on polyvinyl alcohol, crosslinking agent, surfactant, plasticizer, loosening agent, and foam suppressor. Equilibration of qualitative and quantitative composition regarding indicated constituents enables formation of strong multifunctional material allowing adequate effluent of exudate and irreversible removal of microbial bodies and their vital activity products from wound surface, suppresses pathogenic microflora, and also allows anti-inflammatory, anti-edematous, and analgesic effects thereby stimulating reparative processes in the wound.

EFFECT: enhanced therapeutical effect.

16 cl

Description

The invention relates to medicine, namely to medical open-porous sorption non-woven materials and products based on it, in particular wound coverings, dressings, drainage and etc. Products from this material can be used in ophthalmology, microsurgery, general, cardiovascular and maxillofacial surgery, gynecology, dentistry, otolaryngology and other fields of practical medicine.

Known non-woven materials from cellulose fibers and products based on it. However, these materials during rupture or deformation, as a rule, form uneven and fleecy surfaces. Fiber bonding through a chemical binder increases the density of such materials and gives them other valuable practical properties. However, as soon as the material is wetted, valuable properties are sharply reduced, and especially when the material is saturated with liquid.

Known materials made from synthetic fibers are characterized by structural integrity and significant tensile strength. However, they do not meet the affixation requirements necessary for use in the hygiene industry.

Another category of medical materials are porous polymeric materials. The closest analogue to this invention is a lint-free porous sorption material for medical purposes based on polyvinyl alcohol, a crosslinking agent, mineral acid, sodium chloride, a foaming agent (RU 2151615).

The disadvantage of this material is its lack of sorption ability and ductility, which does not allow to accurately model the wound surface.

The aim of this invention is to provide a lyophilized medical material having enhanced sorption, drainage ability and good plasticity to simulate the shape of the wound surface or wound cavity.

This goal is achieved by creating an open-porous, plastic, sorption material based on polyvinyl alcohol (PVA), a crosslinking agent, a surfactant, a plasticizer, a loosening agent, and a foam suppressing agent.

The balance of the qualitative and quantitative composition of these components allows to obtain a complex action material with a hemostatic effect, providing an adequate outflow of exudate. This material irreversibly removes microbial bodies and products of their vital activity from the wound surface, suppresses pathogenic microflora, provides anti-inflammatory, decongestant, analgesic effects, thereby stimulating the effect on reparative processes in the wound.

The degree of crosslinking of PVA affects such functional properties of the material as the ability to absorb wound fluid, modeling the wound surface of the wound, and adhesion to tissue. The amount of crosslinking agent is sufficient to achieve the desired properties, such as strength in dry and wet conditions. However, the amount of crosslinking agent may be different from the end use of the material. So, for example, to increase the strength of the material, the amount of crosslinking agent can reach a high value, while a smaller amount of chemical crosslinking agent can be used to increase the ductility of the material. Fatty aldehydes, for example, succinic aldehyde, isovalerian aldehyde, can act as a crosslinking agent. The crosslinking agent may contain a hydrophilic segment. The desired quantitative ratio of PVA to crosslinking agent may be about 5: 1-1: 5, more preferably 3: 1-1: 3, and most preferably about 2: 1-1: 2.

As a plasticizer, any known plasticizer can be used, for example polyethylene glycol, glycerin. As a baking powder, starch is mainly used.

The thickness of this material largely depends on the intended use and can vary widely from 0.15 to 5 mm.

According to a preferred embodiment of the invention, the material is obtained by carrying out the polymerization process in any conventional manner known to a person skilled in the art, PVA with a crosslinking agent in the presence of disintegrant, surfactant and antifoam agent, wherein the disintegrant, antifoam agent and surfactant are subsequently washed with water. After the polymerization process is completed, the material is formed in accordance with its purpose, dried and sterilized.

The material of the present invention may optionally further comprise water-based ointments, medicinal substances that are administered during mixing of the PVA with a crosslinking agent or applied directly to the finished material.

A directional regulation of the pharmacodynamic properties of this material due to changes in the molding temperature and the introduction of antimicrobial substances containing functional groups of a basic nature has been established. So, the material can be modified with various growth enzymes, antiseptic drugs, for example, gentamicin, lincomycin, chlorhexidine, etc., as well as saturated with solutions of glucose (20-40%), ascorbic acid (5%). The material may also optionally contain a local analgesic, such as lidocaine.

When studying the deformation-strength characteristics, it was found that the strength of the analog material when wetted drops by 5-10 times, as a result of this, in some cases, the material loses its structural strength. The maximum tensile elongation, reflecting the elasticity of the material according to this invention, when moistened increases by 2 times. The degree of adhesion to the wound surface (or atraumatism) with respect to medical gauze was 48-55%, which indicates the possibility of fixing this material without using an adhesive layer and removing without significant trauma to the underlying tissues. However, if necessary, the material may contain a layer of adhesive coating around the perimeter.

Thus, an atraumatic, sorption, plastic, and durable material was obtained whose inhibitory activity persists after two days of contact with a model liquid medium.

The material is used in surgery, namely when closing clean chipped, cut, bruised wounds, which allowed to reduce the number of purulent complications by one and a half times. Closure of postoperative wounds during primary treatment, purulent wounds after surgery, closure of sutures during celiac surgery also reduced the number of purulent complications by 40%. In the treatment of traumatic injuries, accelerated healing processes, a rapid decrease in edema and hyperemia were noted.

This material is also applicable for parenchymal bleeding. In place, a combination of this material with hemostatic agents, for example with lyophilized feracryl, is possible.

Topical application of this material in combination with lyophilized feracryl for anatomical resection of dogs’ spleens leads to a stop of bleeding for 8-10 seconds after application. During histological examination, thrombosed vessels, fibrin filaments and polymorphonuclear leukocytes are visible in the plane of the spleen section. At the border with healthy tissue, there is proliferation of fibroblasts, the rudiments of granular tissue.

Based on this material, a combined coating for wounds and burns was created, consisting of at least one additional layer of the 3 listed layers:

- adjacent to the wound material according to this invention,

- the middle layer of hydrophilic superabsorbent,

- the upper air- and vapor-permeable micro-impermeable layer.

In these cases, the material may further comprise a porous nylon membrane with an average pore size of 0.2 μm. The membrane is chemically resistant and biologically inert, sterilized in an autoclave. The membrane instantly absorbs water up to three times its own weight, the surface is smooth and highly elastic.

The comparative results of studying the effect of the material on the wound process reflect the following data: the use of material for the treatment of purulent wounds immobilized by enzymes (trypsin, terrilithin, lysozyme, collagenase-C, protease-C, etc.) leads to a significant reduction in the time for cleansing wounds from purulent necrotic masses and reduces their bacterial contamination in relation to the group of untreated experimental animals by 43.3-52.5% in the case of using the native form of the material, and when immobilizing enzymes - by 48.3-64.6%; healing by 16.7-24.7% and 32.2-33.3%, respectively.

The introduction of chlorhexidine bigluconate (1.0%) additionally into the material modified with enzymes leads to a significant reduction in the time of purification and healing of purulent wounds.

Also, based on this material, a drainage device can be made in the form of a coating, strip, rolled into a roll or tube. The drainage device may further be perforated. After the formation of juicy granulation, the drainage device is easily separated.

Based on the material, medical products can be produced, for example, such as applicator plates, napkins, tuffers, turunds of various shapes, in particular for draining the surgical field or wound and burn surfaces.

A wound cover made of this material is convenient and safe, it can be used for dressing at home, to cover household injuries (burns, cuts, abrasions, etc.). Thanks to the calming effect, coatings are especially suitable for treating minor injuries in children. There were no allergic complications when using the material as a medical material of widespread use.

The proposed material is recommended for its widespread use in various fields of surgery, in transdermal administration of drugs, in the treatment of wounds and burns of various etiologies, as well as in first aid in everyday conditions.

Claims (16)

1. Medical open-porous sorption material based on polyvinyl alcohol (PVA), a crosslinking agent, a surfactant, a plasticizer, a loosening agent, and a foam suppressing agent. 2. The material according to claim 1, characterized in that it contains a fatty series aldehydes as a crosslinking agent. 3. The material according to claims 1 and 2, characterized in that the crosslinking agent contains a hydrophilic segment. 4. The material according to claims 1 to 3, characterized in that it contains at least one of the above 3 layers: the material adjacent to the wound according to this invention, a hydrophilic superabsorbent layer, an upper air- and vapor-permeable micro-impermeable layer. 5. The material according to claims 1 to 4, characterized in that it additionally contains a drug. 6. The material according to claims 1-5, characterized in that it contains enzymes. 7. The material according to claims 1 to 6, characterized in that it contains a local analgesic, for example lidocaine. 8. The material according to claims 1 to 7, characterized in that it additionally contains lyophilized feracryl. 9. The material according to claims 1 to 8, characterized in that it is the basis for the manufacture of dressings. 10. A dressing made of a medical open-porous sorption material based on polyvinyl alcohol (PVA), a crosslinking agent, a surfactant, a plasticizer, a loosening agent, and a foam suppressing agent. 11. The dressing according to claim 10, characterized in that the material contains at least an additional one of the 3 listed layers: the material adjacent to the wound according to this invention, a hydrophilic superabsorbent layer, an upper air- and vapor-permeable micro-impermeable layer. 12. A dressing according to claim 10, characterized in that it is made of material according to claims 2-8. 13. The dressing of claim 10, characterized in that it is made in the form of a plate-applicator, wipes, tupfer, turunda of various shapes. 14. The dressing according to claim 10, characterized in that it is made in the form of a drainage device. 15. The dressing according to claim 10, characterized in that the drainage device is made in the form of a coating, strip, rolled up into a roll or tube. 16. The dressing according to claim 10, characterized in that the drainage device can additionally be subjected to perforation.