WO1990011744A1

WO1990011744A1 - Wound dressing

Info

Publication number: WO1990011744A1
Application number: PCT/GB1990/000499
Authority: WO
Inventors: Leung Lit Hung
Original assignee: Leung Lit Hung
Priority date: 1989-04-03
Filing date: 1990-04-03
Publication date: 1990-10-18
Also published as: GB8907444D0; AU5355590A

Abstract

A dressing for a wound comprises an inflatable device (3) which is applied over the wound and inflated to exert external pressure on the wound to improve healing thereof. The inflatable device (3) may be attached to the wound by means of an adhesive strip (2) having the inflatable device secured to its external surface (4). In an alternative embodiment to be used as a dressing for a fractured bone, the inflatable device, in a partially inflated state, is applied to the limb having the fractured bone and the limb is set with a plaster cast applied over the inflatable device. Inflation of the latter can then be adjusted to vary the tightness of the cast.

Description

WOϋ D DRESSING

The present invention relates to dressings for wounds, for example, surgical wounds or other injuries, such as, bone fractures.

As medical science advances, surgery is becoming increasingly common and, in most cases, is accompanied by a skin wound. However, healing of the skin wound is often unsatisf ctory in that infection, or occasionally wound dehiscence, can occur. The exact mechanism or the factors affecting wound healing are still relatively unknown to the medical profession and the achievement of a well-healed wound without complications is still being pursued. Some facrors are known to affect wound healing unfavourably, and some of these are related to surgical technique which, with proper training and correct procedure, could be avoided. Other indigenous factors could also probably be avoided by good planning. However, one factor which is consistently present is the swelling of tissue in a surgical wound. This tissue swelling can be due to cellular swelling as a direct result of injury to the cells; exudation of inter¬ stitial fluid; and/or accumulation of serous fluid in the wound. Any of these causes of tissue swelling can effec¬ tively lead to a decrease in the chance of good healing of the wound and an increase in the likelihood of infection.

In order to reduce such tissue swelling, it has been found that the application of external pressure to the wound is effective. This pressure can be achieved to a certain extent by using a pile of cotton dressing on the wound, over which a tight elastic dressing is applied so that the cotton dressing presses onto the wound. However, this procedure is often tedious and sometimes cannot be used for physiological reasons. For instance, such a dressing cannot be applied to the neck or chest, as it would restrict the patient's breathing.

It is an object of the present invention to provide a wound dressing which inhibits tissue swelling of the wound and overcomes the problems of known types of dressing

SUBSTITUTESHEET -z-

used for this purpose.

Accordingly, the present invention consists in a dressing for a wound or other injury including inflatable means for applying external pressure to the wound or other injury.

In a preferred embodiment, the inflatable means comprises an airtight bag made, for example, from a plas¬ tics material, having an air inlet/outlet to enable the bag to be inflated and deflated in similar manner to a balloon. The air inlet/outlet may include a shut-off valve, for example a stop cock, to maintain the bag in an inflated state.

Advantageously, the dressing includes means for securing the inflatable means over the wound. For example the inflatable means may be attached to a piece of suitable material for covering ^"the wound. Preferably, the inflata¬ ble means is attached to an outer surface of the material which is intended to face away from the wound, and an inner or under surface of the material which is intended to face the wound may be made adhesive to adhere directly to the skin surface surrounding the wound. The adhesive surface may be covered by a removable layer made, for example, of paper, which is intended to be peeled off before the piece of material is adhered to the skin surface.

The invention will be further described by way of example with reference to the accompanying drawings, in which:-

Figure 1 shows schematically a plan view of a wound dressing, in accordance with an embodiment of the present invention, when in an inflated state,

Figure 2 shows schematically an end view in the direction indicated by arrow A in Figure 1,

Figure 3 shows schematically a sectional view taken along line B-B in Figure 1,

Figure 4 shows schematically an end view of the wound dressing when in a deflated state, and

Figures 5 and 6 show schematically a plan view and end view respectively of another embodiment of the present invention .

Referring to Figures 1 to 4 of the drawings, a dressing for a surgical wound, the position of which is shown by a dotted line 1 in Figure 1, consists of a strip 2 of dressing material and an inflatable device 3 attached to an outer surface 4 of the material, which is intended to face away from the wound.

The material strip 2 has an adhesive inner surface 5, which is intended to face the wound and adhere to the skin surface around the wound. The adhesive surface 5 is protected by a paper line 6 which, when peeled away, ex¬ poses the adhesive surface 5 to enable it to be applied to the skin surface.

The inflatable device 3 consists of a balloon-like airtight bag 7 made from a plastics material and having an air inlet/outlet to enable the bag 7 to be inflated and deflated. The air inlet/outlet consists of a plastics tubing 8 connected to, or integral with, the bag 7 and a stop cock 9 to prevent air escaping from the bag 7 once it has been inflated.

In Figures 1 to 3, the device 3 is illustrated in its inflated state to provide the applied pressure, and Figure 4 shows the device when it is deflated and thus not applying any pressure.

When the dressing is required to be applied to a surgical wound, the paper liner 6 is peeled off and the dressing material is adhered to the skin with the inflata¬ ble device 3 positioned over the wound. The bag 7 is then inflated with air, via the air inlet/outlet, which may be connected to a suitable air supply, such as a syringe. When the air inside the bag 7 is at a required pressure, the stop cock 9 is closed to maintain the bag in its in¬ flated state.

The device, when inflated in this manner, thus applies external pressure to the wound to inhibit swelling of the wound tissue.

The dressing in accordance with the present invention, can be used to apply external pressure to a wound on any part of the patient's body without any poten¬ tially harmful physiological restrictions.

By application of such external pressure to the wound, it has been found that cellular swelling is reduced. Furthermore, the applied pressure causes the two sides of the wound actually to adhere to each other, thereby reduc¬ ing the space available for the accumulation of fluid in the wound.

The bag of the inflatable device, as illustrated in Figures 1 to 4, has an elongated shape and a generally rectangular cross-section. However, the bag may have any appropriate shape and/or size depending on the shape or size of wound to be dressed.

Figures 5 and 6 illustrate another embodiment of the present invention, which consists of an inflatable device 10 comprising an elongated inflatable strip 11 formed with a plurality of longitudinal grooves 12.

This inflatable device 10 is particularly useful as a dressing for fractured bones, when a plaster cast is applied to immobilise a fractured long bone, it may be too tight thereby causing tissue necrosis, or too loose thereby not fulfilling its function of immobilising the bone. Furthermore, there may also be circumstances where the tension of the plaster cast is correct when first applied, but after a short period, when initial swelling of the tissue subsides, the cast becomes too loose.

To overcome these problems, the inflatable device 10 is first applied over the limb with the fractured bone and half inflated and the plaster cast is then applied over the device. If the final cast is too tight, the device 10 can be deflated to reduce the pressure on the fracture. On the other hand, if the cast subsequently becomes too loose, then the device 10 can be further inflated to increase the pressure on the fracture.

Whilst particular embodiments of the present inven¬ tion have been described, various modifications will be envisaged without departure from the scope of the inven¬ tion, as defined by the appended claims.

Claims

C AIMS

1. A dressing for a wound or other injury, characte¬ rised by inflatable means (3,10) for applying external pressure to the wound or other injury.

2. A dressing according to claim 1, characterised by means (2) for securing the inflatable means (3) over the wound.

3. A dressing according to claim 2, characterised in that the inflatable means (3) is disposed on the outer surface (4) of a strip or other piece of flexible dressing material ( 2 ) for covering the wound.

4. A dressing according to claim 3, characterised in that the flexible dressing material (2) has adhesive on its under surface (5) for adhering the dressing to the skin surface about the wound.

5. A dressing according to claim 4, characterised by a protective liner (6) releasably attached to the adhesive surface (5) .

6. A dressing according to any preceding claim, cha¬ racterised in that the inflatable means (3) comprises a fluid-tight bag, for example, made from plastics material, and having an inlet/outlet (8) for permitting inflation and deflation of the bag.

7. A dressing according to claim 6, characterised in that the inlet/outlet (8) includes a shut-off valve (9).

8. A dressing according to claim 1, characterised in that the inflatable means (10) is in the form of an in¬ flatable strip-like device (11) having a plurality of longitudinal grooves (12) in one face thereof.

9. A method of treating a wound or other injury, characterised by the steps of disposing an inflatable means (3,10) over the wound or other injury, and inflating the inflatable means to apply external pressure thereto.

10. A method according to claim 9, characterised by adhering the inflatable means (3) over the wound and there¬ a er inflating said inflatable means.

11. A method according to claim 8 for treating a rac- tured bone injury, characterised by the steps of applying the inflatable means (10) to the limb having the injury, partially inflating the inflatable means, applying a plaster cast to the limb and over the inflatable means, and adjusting the inflation pressure of the inflatable means to adjust the tightness of the plaster cast.