GB2128479A

GB2128479A - Application of surgical dressings

Info

Publication number: GB2128479A
Application number: GB08327331A
Authority: GB
Inventors: Peter William Berry
Original assignee: Smith and Nephew Associated Companies PLC
Current assignee: Smith and Nephew PLC
Priority date: 1982-10-20
Filing date: 1983-10-12
Publication date: 1984-05-02
Also published as: GB8327331D0

Abstract

Adhesive dressing 1 comprises a) a bacteria-proof transparent film 2 b) an adhesive coating 3 c) a pair of release sheets 5, 6 having their free edges 7, 8 situated away from the sides of the dressing, so that the middle part of the dressing can be applied first. <IMAGE>

Description

SPECIFICATION Application of surgical dressings The present invention relates to conformable, bacteria proof adhesive dressings for use on the skin and to the application of such dressings to the human body. In particular, this invention relates to self-adhesive conformable dressings in a presentation which allows easy and sterile application of the dressings.

Certain favoured self-adhesive conformable dressings known in the art comprise a polymeric film having an adhesive on at least part of its surface. Such dressings are sold for various uses which include attaching catheters to the body.

Several presentations of such dressings are known and include the following: A first dressing, known as Bioclusive Transparent Dressing (trade mark of Johnson and Johnson Products Inc.), is a self-adhesive conformable film presented so that it is adhesive over the major part of one of its surfaces, leaving a non-adhesive tab at one side-edge, the total area of the film being co-terminous with a backing sheet to which the self-adhesive part of the film is adhered, the non-adhesive tab and the corresponding part of the backing sheet being perforated to allow removal of the tab.

A second dressing, known as Ensure (trade mark of Parke Davis and Co.), is a self-adhesive conformable film, presented with the adhesive surface of the film adhered to a removable backing sheet, the film having attached thereto, along one side-edge, a first non-adhesive tab, the nonadhesive surface of the film being covered with a removable protective layer which has, along one side-edge, a second non-adhesive tab attached by the side-edge of the tab remote from the centre of the protective layer.

A third dressing is known which is a selfadhesive conformable film, presented as described in European Patent Application No. 51-935. In one of these presentations, available as Tegaderm Transparent Dressing (trade mark of Minnesota Mining and Manufacturing Co.), the adhesive surface of the film is adhered to a backing sheet or release liner, the backing sheet being wider than the film, thus forming a tab at one side-edge to allow removal of the backing sheet, the nonadhesive surface of the film being covered with a removable protective layer or releasable layer having a centre cut-out which, when removed, forms a window, the remaining frame being removable by means of a tab along its side-edge or by means of a split in the frame.

In each of the known presentations, therefore, the means for releasing the backing sheet from the film is situated at a side-edge of the film. It has been found that this can result in difficulties in centring the dressing about a catheter (or part of the body), since one side of the dressing adheres to the catheter before the other side can be positioned. This in itself also leads to the possibility of 'rucking' of the dressing, leaving gaps around the catheter and surrounding skin which defeats the aim of sterility.

Other difficulties arising with the abovedescribed hitherto known presentations include major problems in applying the dressing without touching the adhesive, thereby defeating the aim of sterility.

The first dressing described above also suffers from the disadvantage of having to remove a tab from the dressing once it is in place; this can cause movement and rucking of the dressing.

The present invention helps overcome these problems by providing a dressing comprising a self-adhesive conformable film adhered to a removable protector, which protector has means in the form of handles for releasing it from the film, characterised in that the release means is situated away from the side-edges of the protector.

It is clear from the above therefore that the present invention provides an adhesive dressing suitable for use on the skin which consists essentially of (a) a bacteria proof, transparent film, coated with adhesive on one face, (b) a protector over the whole of the adhesive which protector consists of a first part and a second part, the first part disposed over one side of the dressing and the second part disposed over the remainder of the dressing said first and second parts being adapted to provide handles whereby said first and second parts can be grasped and peeled away from the adhesive.

The first and second parts of the protector together cover the whole of the adhesive face of the film. The two parts meet or overlap at a point away from the edge of the dressing. The two parts may be of unequal areas but preferably they will have an approximately equal area in contact with the adhesive face in which case the two parts will meet or overlap about a line approximately at the centre of the dressing. Such a dressing is within the scope of the present invention.

Thus in a favoured aspect the present invention provides a dressing which consists essentially of (a) a bacteria proof transparent film coated with adhesive on one face and (b) a protector over the whole of the adhesive characterised in that the protector comprises a first and second part, the first part disposed to one side of the dressing and the second part disposed over the remainder of the dressing, said first and second parts abutting and each of said first and second parts possessing a a portion bent back away from the plane of the dressing whereby said first and second parts can be grasped and peeled away from the adhesive.

Most aptly the first and second parts abut along an approximately central line across the face of the dressing.

This invention therefore includes the advantage of being able to position the dressing over a catheter (or part of the body) so that a middle part of the dressing first adheres to the catheter. By 'a middle part' is meant a part of the dressing which is not a side-edge. The protector can then be gradually released from the middle in a direction towards each side-edge, thereby greatly reducing the possibility of rucking the dressing and increasing the chances of maintaining sterility.

The two parts of the protector may abut each other where they meet as described above or more preferably the second part may overlie a portion of the first part of the protector without having a bent back portion or may overlie a portion of the first part of the protector and then have a bent back portion.

Thus in a preferred aspect the present invention provides an adhesive dressing suitable for use on skin which consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector layer over the whole of the adhesive which protector comprises a first part and a second part, the first part disposed to one side of the dressing and the second part disposed over the remainder of the dressing, said first part possessing a portion which is bent back away from the plane of the dressing, said second part overlapping on to the first part over the bent back portion whereby said first and second parts can be grasped and peeled away from the adhesive.

In a further preferred aspect the present invention provides an adhesive dressing suitable for use on the skin which consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector layer over the whole of the adhesive which protector comprises a first part and a second part, the first part disposed to one side of the dressing and the second disposed over the remainder of the dressing, each of said first and second parts possessing a portion bent back away from the plane of the dressing, the second part being adapted to overlap the first part at least over part of the bent over portion of the first part whereby said first and second parts can be grasped and peeled away from the adhesive.

The conformable film for use in the present invention is preferably a transparent polymeric film so as to allow observation of the surface to which the dressing is to be adhered.

The film may itself be multi-layer and may include more than one continuous and/or interrupted polymeric layer.

Examples of suitable films, and adhesives therefor, are described in British Patent Specification No. 1 ,280,63 1, European Patent Specification No.51-935 (especially the polyurethanes) and suitable films prepared from the hydrophilic polyurethanes are disclosed in European Patent Specification No. 50035. Films, and adhesives, described in these specifications as 'preferred' are also to be taken to be preferred for use in the device of this invention.

The adhesive coated film most suitably transmits moisture vapour at a rate of at least 300 g/m2/24 hrs/370C/100-10% RH, desirably at least 400 g/m2 and more favourably at least 500 g/m2 and preferably at least 700 g/m2.

The film is desirably formed from polyurethane which is 9 to 35 microns thick, more suitable 10 to 30 microns thick and preferably from 20 to 25 microns thick.

The adhesive may be an all over spread, pattern spread, a microporous layer or a porous layer or the like. The adhesive may be pattern spread using the method described in British Patent No.

819635. The adhesive may be formed as a porous layer by the method described in British Patent No. 1,563,695. Both these patents are incorporated herein by cross reference. However, it is preferred that the adhesive is in the form of an all over spread, that is as continuous layer containing no pores or micropores.

Suitable adhesives which are moisture vapour transmitting as an all over spread or continuous layer include various acrylate ester copolymer and polyvinyl ether pressure sensitive adhesives for example as disclosed in British Patent No.

1,280,631. Favoured pressure sensitive adhesives comprise copolymers of acrylic ester with acrylic acid for example as disclosed in United Kingdom Application No. 2,070,631.

A preferred pressure sensitive adhesive comprises a blend of high and low viscosity polyvinyl ethyl ether disclosed in British Patent No.

1 280,631. A second preferred pressure sensitive adhesive is disclosed in United Kingdom Application No.2,070,631 as a copolymer of 47 parts by weight 2-ethyl-hexylacrylate, 47 parts by weight butyl acrylate and 6 parts by weight acrylic acid polymerised in acetone.

The adhesive is suitable employed at weights per unit area of 10 to 75 gum~2, more usually 15 to 65 gum~2, preferably at 25 to 40 gum~2 for example 29 gum~2,32 gum~2 The protector may be any convenient material used for such purposes such as a polymer or paper film and especially those treated for easy release properties, for example by siliconisation.

The protector for use in this invention may comprise any material known to those skilled in the art or described in the above-listed specific#tions. Preferably, the backing sheet is of transparent or translucent material such as poly(vinyl chloride) or siliconised paper, such as siliconised glassite paper or other siliconised polymers such as high or low density polyethylene which have been surface treated.

In another aspect, the present invention therefore provides a method of applying a dressing as hereinbefore described, which method comprises positioning the dressing over the surface to which it is to be applied, such that the protector is adjacent the surface, and removing the protector from the film, characterised in that the first part of the dressing to adhere to the surface is way from the side-edges of the backing sheet.

Especially preferred is a method wherein release means, situated away from the side-edges of the protector are used to release the protector.

In a further aspect, the present invention provides a method of preparing such a dressing comprising applying adhesive to at least a part of a conformable transparent polymeric film, affixing to said part of the film a protector having means for removing the protector from the film which means is situated away from the side-edges of the protector, and sterilising the resulting dressing.

In a still further aspect, the present invention provides a dressing according to the invention contained in a bacteria proof package.

Preferably, the package contains or incorporates instructions on how to use the device according to the invention.

One favoured dressing of this invention comprises a dressing 10 cm x 10 cm which is a 25 micron thick polyurethane film (such as an Estane 5701 F, trade mark of B. F. Goodrich) coated over one face with a 25 micron thick layer of acrylic adhesive (such as the preferred adhesive of European Patent Application No. 51935) in which dressing a protector comprises two 10 cm x 6 cm pieces of siliconised glassite paper placed so that each has a 10 cm x 5 cm portion which overlays the adhesive and a 10 cm x 1 cm strip folded back to provide a handle.

A second favoured dressing of this invention comprises a dressing 10 cm x 10 cm which is a 25 micron thick polyurethane film (such as an Estane 5701 F, trade mark of B. F. Goodrich) coated over one face with a 25 micron thick layer of acrylic adhesive (such as that whose preparation is described in Example 1 of United Kingdom Patent Application No. 2070631) in which dressing a protector comprises two 10 cm x 6 cm pieces of siliconised high density polyethylene so that for the first part a 10 cm x 5 cm portion overlays the adhesive and a 10 cm x 1 cm strip is folded back and for the second part a 10 cm x 5 cm portion overlaps the adhesive and the remaining 10 cm x 1 cm strip is unfolded and overlays the first part.Alternatively the second part may be a piece which is 10 cm x 7 cm, a 10 cm x 5 cm portion overlays the adhesive whilst a strip 10 cm x 0.5 cm overlays the first part of the protector, the remaining 10 cm x 1.5 cm strip being folded back to provide a handle.

The present invention will now be illustrated by way of example only, with reference to the accompanying drawings in which: Figure 1 shows a cross-sectional view of a dressing according to this invention; and Figure 2 shows a plan view of a dressing according to this invention.

Figure 3 shows a cross-section view of a dressing according to another aspect of this invention; Figure 4 shows a cross-section view of a dressing according to a further aspect of this invention.

Referring first to Figure 1 , the dressing 1 comprises a conformable film 2 of polyurethane on one surface of which is spread an acrylic adhesive 3 to which surface is adhered a protector 4 of poly(vinyl chloride) or siliconised paper or siliconised polyethylene.

The protector 4 just overlaps the film 2 and is in two parts 5 and 6. Each of the two parts 5 and 6 terminate towards the middle (but not necessarily in the centre) of the sheet 4 in tabs 7 and 8 which overlap so that the total surface of the adhesive 3 is covered.

Figure 2 shows the extent of the overlapping 9 between tabs 7 and 8; and also the overlapping 10 between backing sheet 4 and film 2.

In use, the dressing 1 is positioned so that overlap 9 (Figure 2) is over that part of the catheter (or other surface) which centralises the dressing about the catheter. Tabs 7 and 8 are grasped and gradually pulled toward the corresponding edges of the device, exposing adhesive 3, and gentle pressure is applied so that the dressing adheres to the catheter. The two parts 5 and 6 of the protector 4 are thus removed entirely and disposed of. Thus, film 2 remains adhered to the catheter by adhesive 3.

Figure 3 shows a similar dressing to that described in Figure 1 except that the second part of the protector instead of having a bent back portion 8, overlaps onto the first portion of the protector 5.

Figure 4 shows a similar dressing to that described in Figure 1 except that the first and second parts of the protector abut each other and do not overlap.

The adhesive films employed in this invention may be represented by a membrane coated over one surface with an adhesive layer. Most suitably the membrane is 10 to 40 microns thick and preferably from 20 to 35 microns thick, for example 25 microns thick. Most suitable the adhesive layer is 1#5 to 65 microns thick and preferably from 20 to 40 microns thick, for example 25 to 35 microns thick. Desirably both membrane and adhesive are formed from moisture vapour permeable materials.

Preferably the protector is in two parts which are approximately equal in size so that the two parts come together at approximately the middle of the sheet. Preferably each of the two parts of the protector is adapted to provide handles for example in the form of tabs projecting away from the middle of the sheet (that is part of each of the two parts of the protector is folded back upon itself providing handles).

This invention is particularly effective for materials having an extension of at least 300% at 300 kg/sq. cm.

EXAMPLE 1 Preparation of an Adhesive Dressing A syrup of a polyurethane (Estane 5701 F, trade mark of B. F. Goodrich) in tetrahydrofuran/acetone (solids content 15%) is cast onto a siliconised release paper and the'solvent removed to give a film 30 microns thick.

A solution is acetone of an acrylic ester copolymer formed from the copolymerisation of 47 parts by weight 2-ethyl hexylacrylate, 47 parts by weight butylacrylate and 6 parts by weight acrylic acid is cast onto a siliconised release paper to give a film at a weight of 32 g/m2 after removal of the solvent.

The adhesive layer is then transfer coated by conventional means onto the polyurethane film.

The folded protector in two parts is then placed on the adhesive layer by conventional means so as to cover the whole of the adhesive surface.

The strip thus produced is cut to give individual dressings of the desired size.

The individual dressings may be placed and sealed in a bacteria proof pack and sterilised in a conventional manner.

In use, the sterile dressing is removed from the pack, the two parts of the protector pulled back a little way to expose a small area of adhesive which may be accurately and smoothly placed where required. The remainder of the adjesive surface is then exposed and positioned by removal of the protector.

Claims

1. An adhesive dressing suitable for use on the skin consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector over the whole of the adhesive, which protector comprises a first part and a second part, the first part disposed over one side of the dressing and the second part disposed over the remainder of the dressing, said first and second parts being adapted to provide handles whereby said first and second parts can be grasped and peeled away from the adhesive.

2. An adhesive dressing suitable for use on the skin consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector over the whole of the adhesive, which protector comprises a first and second part, the first part disposed to one side of the dressing and the second part disposed over the remainder of the dressing, said first and second parts abutting and each of said first and second parts possessing a portion bent back away from the plane of the dressing whereby said first and second parts can be grasped and peeled away from the adhesive.

3. An adhesive dressing suitable for use on the skin consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector over the whole of the adhesive, which protector comprises a first and second part, the first part disposed to one side of the dressing and the second part disposed over the remainder of the dressing, said first part possessing a portion which is bent back away from the plane of the dressing, said second part overlapping onto the first part over the bent back portion whereby said first and second parts can be grasped and peeled away from the adhesive.

4. An adhesive dressing suitable for use on the skin consists essentially of (a) a bacteria proof, transparent film coated with adhesive on one face and (b) a protector over the whole of the adhesive, which protector comprises a first and second part, the first part disposed to one side of the dressing and the second part disposed over the remainder of the dressing, each of said first and second parts possessing a portion bent back away from the plane of the dressing, the second part being adapted to overlap the first part at least over a part of the bent over portion of the first part whereby said first and second parts can be grasped and peeled away from the adhesive.

5. An adhesive dressing as claimed in any of claims 1 to 4 in which the first and second parts of the protector abut or overlap along an approximately central line across the face of the dressing.

6. An adhesive dressing as claimed in any of claims 1 to 5 in which the adhesive-coated film has a moisture vapour transmission rate of at least 300 g/m2/24 hrs when measured at 370C and 100% to 10% relative humidity.

7. An adhesive dressing as claimed in any of claims 1 to 6 in which the film is formed from a polyurethane which is from 9 to 35 microns in thickness.

8. An adhesive dressing as claimed in any of claims 1 to 7 in which the in which the adhesive is a polyvinyl ethyl ether adhesive.

9. An adhesive dressing as claimed in any of claims 1 to 7 in which the adhesive is an acrylate ester adhesive.

10. An adhesive dressing as claimed in any of claims 1 to 9 in which the weight per unit area of the adhesive is from 10 to 75 g/m2.

11. An adhesive dressing as claimed in any of claims 1 to 10 in which the protector is a siliconised high density polyethylene.

12. An adhesive dressing as claimed in any of claims 1 to 11 in a sterile form and packaged in a bacteria proof pack.