Wound dressing

Abstract

The invention relates to a sterile wound dressing having a backing and a nonabsorbent elastomer wound contact layer, wherein the elastomer matrix is formed by a synthetic three-block elastomer, preferably a copolymer of polystyrene block and polyolefin block (SEPS, SEBS, SEEPS, etc.) or mixtures thereof, wherein the total polymer content is less than 3.2 wt %, in particular 3.0 wt % or less, preferably 2.6 wt % or less, and is plasticized by an apolar oil and / or petroleum jelly.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is based on and claims priority to European Patent Application No. 11 004 167.0, filed on May 19, 2011, which is incorporated herein by reference in its entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]Not applicable.BACKGROUND OF THE INVENTION[0003]The invention relates to a sterile wound dressing with a backing and an elastomeric polymer matrix as the wound contact layer.[0004]Wound dressings containing fat have been used successfully for many years for topical treatment of traumatic wounds such as cuts and scrapes and chronic wounds, such as decubital ulcers, leg ulcers, and the like, as well as burns on humans and animals.[0005]LOMATUELL H from the company Lohmann & Rauscher GmbH & Co. KG (“L&R”) is tulle impregnated with fat and is one of the products often used for medical care of skin wounds. This product, which is formed from a woven cotton impregnated with a fatty substance based on p...

AI Technical Summary

Benefits of technology

[0025]According to the invention, this object is achieved by a refinement of the known wound dressings, characterized essentially in that the wound contact layer contains an elastomer matrix comprising less than 3.2% of an elastomer, in particular 3.0% or less, preferably less than 2.7% of a total polymer component, so that better tissue compatibility is obtained in addition to the economic advantage.

Problems solved by technology

This product, which is formed from a woven cotton impregnated with a fatty substance based on petroleum jelly, nevertheless has disadvantages such as loss of fatty substances to the handling tools (such as gloves) and to the wound and the wound environment.

This phenomenon often results in the backing being exposed and coming in direct contact with the wound.

If the backing sticks to the wound, this often leads to traumatic changing of the dressing and a disturbance in the wound healing process.

Other commercially available products, e.g., the dressing from Johnson & Johnson ADAPTIC, which is a knit viscose material impregnated with an oil-in-water emulsion, or the product JELONET (Smith & Nephew), which is cotton gauze impregnated with paraffin, fulfill the same purpose as LOMATUELL H but also have properties that are a disadvantage with respect to the loss of fatty substances.

Furthermore, it seems that the known dressings of the fat-impregnated tulle type are too hydrophobic during use and facilitate an unwanted drying of the wound.

When these agents are used, it has proven problematical that the absorbent (superabsorber) in the dressing binds liquid in a gel form.

Under some circumstances, this may cause maceration of the wound.

This is problematical in view of the desired avoidance of direct contact between the elastomer and the wound.

Furthermore, the use of surfactants is not without problems because they have a certain cytotoxic potential.

Wound infections have been shown to delay healing.

However, none of these techniques is suitable without reservation for production of products, in particular those with pharmaceutical applications and in particular products which contain a fat-based elastomer matrix.

Sterilization by saturated steam or dry heat therefore cannot be used because the elastomer matrix and the hydrocolloid do not tolerate high temperatures and extremely high atmospheric humidity well.

Furthermore, with this technique it is not usually possible to obtain a distribution of the sterilizing agent over the entire volume of the elastomer polymer composition, which limits its efficacy.

However, these two known techniques of radiation sterilization also have unwanted effects on the treated elastomer matrix.

In particular, the energy introduced into the matrix by this radiation is high enough to break the carbon-carbon bonds and carbon-hydrogen bonds in the elastomers used and to also cause breaks in the chains in these polymer macromolecules and thereby reduce their average molecular weight, which in turn influences / reduces their properties, in particular their cohesion ability.

Consequently, these aforementioned products are not completely satisfactory either because of difficulties associated with handling in applying or removing the dressing or because of a relatively high polymer price or a certain tissue intolerance of the elastomer polymers or due to the loss of cohesion after radiation sterilization.