CS254459B1 - Skin imitation for temporary covering the traumatic defects namely burnt parts of skin - Google Patents

Abstract

The solution is to replace the skin with a temporary one covering traumatic defects, especially burns, before skin transplantation, consisting of from a multi-layered solid formation whose at least one layer is of nonwoven fabrics made of staple fibers of which at least a portion is a fiber synthetic. Synthetic, such as polypropylene, polyester or polyamide the fibers are in the nonwoven web structure randomly oriented and partially sintered v permeable surface matrix, wherein from the outside of the fabric or inside a multi-layered solid form is a plastic perforated foil, for example polyethylene, is fixed. Skin replacement is especially suited to applications for heavily infected deep burns, partially surgically treated as well as fresh accidental defects character, loss, injury, and that especially with deep structures such as injuries to tendons, nerves, blood vessels and bones.

Description

BACKGROUND OF THE INVENTION The present invention relates to a skin substitute for temporarily covering traumatic defects, particularly burns, prior to a skin transplantation, consisting of a multi-layered unitary structure, at least one layer of which is a nonwoven fabric.

There are certain rules in the treatment of burns that must be followed in certain variations. The burned area, irrespective of the surface area, must be covered as quickly as possible to reduce the loss of fluid from the body. At the same time, it is necessary to get rid of the patient's shock so that treatment can be started, usually surgical.

In addition to limiting the loss of body fluids, temporary skin replacement should meet good modeling ability, immunological compatibility, health safety, reduced heat and energy loss, adhesion to the burn with the least possible traumatization of the patient, matrix for newly formed granulation tissue, and nerves.

For temporary dressing there is the possibility of covering with biological material, which can be an autograph of the patient's own skin, human donor skin homograph or another animal skin heterograft, mostly pig skin, or synthetic materials manufactured by many manufacturers under different trade names.

For example, a temporary leather synthetic cover according to the author's certificate 160 567, which was essentially a two-layer type consisting of an ether type polyurethane foam layer on the back of which a gauze fabric was fixed.

Clinical experience with virtually all known and available polyurethane materials has proven their suitability especially for the treatment of granulation areas prior to transplantation, but not for other indications in the treatment of local burns.

Temporary dermal synthetic cover according to the author's certificate 160 567 has proven itself for its sorption on various granulating surfaces. The fact that it was used for other indications was due to the fact that there was no other suitable covering material with the corresponding properties for which indication. Long-term experimental and clinical tests have convincingly demonstrated that each of the above-mentioned synthetic cover types of temporary skin substitutes has its advantages but also disadvantages. Therefore, it is not realistic, based on the current level of knowledge, to expect that one type of skin replacement will have all the required properties for all situations and indications.

These circumstances and many others, especially humane ones, led to further development and led to the creation of a temporary leather synthetic cover, which by its composition and technological adjustments ensures better utility properties of material, which is raw material and therefore more cost effective and whose production process is technologically simpler .

A temporary skin cover of this type according to the author's certificate 252 578 is a multi-layered unitary structure, at least one layer of which is a non-woven fabric made of staple fibers, at least a part of which are synthetic fibers, for example polypropylene, polyester or polyamide.

Synthetic fibers are randomly oriented in the structure of the nonwoven and are partially rolled into a permeable surface matrix. A membrane of plastic, for example polyethylene, is fixed from the outside, the back of the nonwoven or inside the multilayer unitary formation.

The temporary skin cover in the form of a unitary body formed of suitable synthetic or other hydrophilic fibers according to the invention will replace the polyurethane foam, thereby improving in particular health safety. The plasma membrane not only enhances the utility properties of the unitary formation, such as impermeability to microorganisms, and prevents dehydration of the injured area, but simplifies the technological manufacturing process by eliminating the entire gauze manufacturing process including spinning, chemical weaving, treatment and the like.

Temporary skin cover of this type is particularly suitable for applications on freshly uncrectomized, low-infected deep burns, collection areas in preparation for autotrans plantation, fresh injury defects such as scalpaces, loss of injury, especially with deep structures such as injuries of tendons, nerves, blood vessels and bones, or abdominal organs, which are thus protected from dehydration.

However, it is not suitable for heavily infected deep burns that cause significant secretion.

In these cases, the temporary skin cover cannot perform well because it does not adhere to the injured area and is washed away by secretion.

This deficiency is eliminated by replacing the skin to temporarily cover traumatic defects, in particular burns, before skin transplantation, consisting of a multi-layered unitary structure of which at least one layer is a non-woven fabric made of staple fibers of which at least a part are synthetic fibers such as polypropylene, polyamide, which are randomly oriented in the structure of the nonwoven fabric and partially sintered in a permeable surface matrix according to the invention, characterized in that a perforated plastic sheet, such as polyethylene, is fixed from the outer, backside of the nonwoven fabric or inside the multilayer unitary structure .

The skin substitute according to the invention in the form of a unitary body formed of a nonwoven fabric provided with a plastic film perforated on its outer side, for example polyethylene or subsequently perforated with a polymeric substance, is usable on one side, which makes it possible to monitor the color, appearance and consistency of the secretion. This type is well-suited for applications to heavily infected deep burns, partially surgically treated, as well as to fresh injury defects such as scalpaces, loss injury, especially with deep structures such as tendon, nerve, blood vessel and bone injuries. .

An integral perforated plastic sheet according to the invention excels in particular by its good permeability for secretion, the possibility of controlling the viscosity of the secretion and its transport to the next layer of covering material, good ventilation of injuries requiring by nature, good suction ability, harmlessness, , good manageability, good controlling capabilities, no loosening of its parts into the wound, suppleness after application and moistening, and forms the perfect matrix for the newly formed granulation tissue.

Further advantages of the skin replacement according to the invention will be apparent from the examples given below.

Example 1

On a pneumatic nonwoven machine, a fiber web of randomly oriented fibers having a basis weight of about 300 g.m is formed from polypropylene staple fibers of a fineness of 3.9 dtex and a length of 60 mm. This fibrous web containing 100% polypropylene staple fibers is thermally solidified without needling using a calender at temperatures of 160 ° C upper roll, 159 ° C lower roll, 18 t down pressure and 6 m.min. . The upper calendering roller contains a special engraved and tested engraving which is formed on the nonwoven matrix of the matrix for the newly formed granulation tissue. The surface of the nonwoven treated in this way has proven itself both under experimental and clinical conditions.

The prepared textile formation is cut to the required dimensions. At the same time, a perforated polyethylene foil having an original basis weight of 35 gm is prepared to the same dimensions and welded with the textile material at the periphery.

Example 2

On a pneumatic nonwoven device, a fiber web of randomly arranged fibers having a basis weight of 150 gm ^{-2 is} formed from polyamide staple fibers of 3.9 dtex and a length of 60 mm. This fibrous web containing 100% polyamide staple fibers is thermally bonded to a calender whose upper roll is heated to 165 ° C and the lower roll is unheated.

At the same time, a perforated film having an original basis weight of 2 is laminated onto the fiber web

g.m, which enters the calender between the lower roller and the fiber web. The calendering speed during laminating is approximately 10 m.min.

Example 3

In a further operation, a fiber web produced and thermally bonded as described in Example 1 is coated with a melt layer formed from polyethylene granules or powder on a coating apparatus at a temperature of 135 to 140 ° C, thereby forming a -2 polyethylene foil with a flat area on one surface of the fabric. weight 35 gm. The whole formation is finally perforated.

Example 4

Polyester staple fibers are fineness on a pneumatic nonwoven device

3.1 dtex and a length of 60 mm form a fibrous web with randomly arranged fibers having a basis weight of 150 g.m. This fibrous web containing 100% polyester staple fibers is thermally consolidated by calender at temperatures of the upper roller 220 ° C, the lower roller 205 ° C, a pressure of 20 t and a speed of 8 m.min. wherein a layer of amorphous synthetic material is formed on both its surfaces.

The textile formation thus prepared is in the next operation flat-bonded with a perforated polyethylene-2 foil with an original basis weight of 35 g.m

The bonding of the textile formation and the perforated polyethylene film is carried out on the calender by laminating. This operation results in a layered formation, one surface of which is provided with a perforated polyethylene film firmly bonded to the textile base and the other surface is non-adhesive to burns or other skin defects.

Example 5

On a pneumatic nonwoven device, a mixture of polyester staple fibers is fineness

3.1 dtex and 60 mm length and hydrophilic viscose staple fibers of 3.9 dtex and -2 mm length will form a fibrous web with randomly arranged fibers of 150 g.m.

This fibrous web comprising 80% polyester staple fibers and 20% hydrophilic viscose staple fibers is thermally consolidated by calender at temperatures of 225 ° C top roller, 210 ° C bottom roller, 20 t down pressure and 8 m / min.

Furthermore, fineness is produced from polyester fibers on the nonwoven pneumatic device

3.1 dtex and 60 mm long fiber web with randomly arranged fibers of 30 g.m.

This fibrous web of 100% polyester staple fibers is thermally hardened by calender at temperatures of the upper roller of 220 ° C, the lower roller of 205 ° C, a pressure of 20 t and a speed of 16 m / min. substances.

Between the two nonwoven webs prepared above, a -2 perforated polyethylene film having an original basis weight of 35 gm is thermoplastically fixed and the resulting formation is adjusted to the desired size.

The sheets formed according to Examples 1 to 5 are packaged in an impermeable package, which may be made of polyethylene film, polyethylene-coated paper and the like. The wrapped blanks are sterilized by irradiation at a dose of 25 kGy.

Claims (1)

SUBJECT OF THE INVENTION Replacement skin for the temporary coverage of traumatic defects, in particular burns, before skin transplantation, consisting of a multilayer unitary body, at least one layer of which is a non-woven fabric of staple fibers, at least a part of which is synthetic, for example polypropylene, polyester or polyamide they are randomly oriented in the structure of the nonwoven fabric and are partially sintered in a permeable surface matrix, characterized in that a plastic film, such as polyethylene, is fixed from outside, the back of the nonwoven fabric or within the multilayer unitary formation.