GB2423019A

GB2423019A - Wound dressing and wound treatment system including the wound dressing

Info

Publication number: GB2423019A
Application number: GB0502650A
Authority: GB
Inventors: Allen Green; Keith Williams; Mark Holmes
Original assignee: IND Ltd AK
Current assignee: IND Ltd AK
Priority date: 2005-02-09
Filing date: 2005-02-09
Publication date: 2006-08-16
Also published as: GB0502650D0

Abstract

A wound suction dressing (10) including a continuous surface provided with a plurality of suction apertures. The wound dressing (10) may be of coiled whole or part tubular form. The dressing (10) can be sized to the wound area by uncoiling part of the dressing (10) and cutting the uncoiled portion. This is a simple procedure which does not impair the effectiveness of the dressing (10). A plurality of apertures (18) is provided in the dressing (10) and suction means is connectable to the dressing (10) to provide a suction force at a contact surface of the dressing (10) and thus to a wound bed for the purposes of removing exudate from the wound. The dressing structure provides a more reliable and controllable suction force at the wound area. A wound treatment system including the wound suction dressing (10), a suction overlay and connections to vacuum source.

Description

The present invention relates to wound management apparatus and in

particular to a dressing system for treating open wounds.

Open wounds, in particular incisional and cutaneous fistulae which are too large to close rapidly, pose particular treatment problems. More specifically, it is necessary to treat sepsis at the wound and to drain the fistula during the healing process. Furthermore, the wound is an area stasis in which there is swelling of the tissues, resulting in insufficient flow of blood to the tissues and thus a reduction in the amount of nutrients to the wound area.

The closure of such wounds by suturing, for example, is far from an ideal solution because this causes stressing of the surrounding skin tissue, does not treat sepsis or allow proper healing. Often, such covered wounds become infected and there is substantial scarring.

Another approach, practised since the 1950's, has been to drain wounds of their exudate, particularly by the use of ostomy pouches and more recently by pouches Is specifically designed for such purposes.

In 1989, Mark E Chariker et al, in "Effective Management of Incisional and Cutaneous Fistulae with Closed Suction Wound Drainage", Contemporary Surgery, Volume 34, June 1989, published the results of research they carried out on such prior art systems. They discovered that healing is substantially improved if exudate from the wound is continually removed, which can contribute to a significant reduction in inflammation at the wound and of necrosis of the localised tissue. Inflammation of the tissue and the formation of eschar produce a mechanical barrier to wound healing.

Chariker et al developed a closed suction system in which a gauze moist dressing is applied over the open wound. The gauze dressing is sized and shaped to fit into the open wound area. A vacuum drain is then placed over the gauze and a closed suction system then fitted over the wound and dressing, operated continuously during treatment. They found that this prevents eschar formation which in turn decreases the degree of fibroplasia, with an increased rate of reepitheliazation. The conformation of the gauze dressing to the wound bed can prevent overgrowth of surrounding tissue, reduce inflammation of the wound and contribute to the natural formation of new skin tissue at the wound area.

WO93/09727 discloses a similar closed suction system, in which the gauze is replaced by a flat porous semi-rigid element, made for example from an open cell polymer foam material configured to overlie the wound. This foam element, as the gauze, acts to absorb exudate form the wound bed, which is then removed by the vacuum drain.

The gauze and foam element need to be replaced at regular intervals, the length of the intervals being dependant primarily on the rate of production and viscosity of the exudate. Moreover, these elements need to be shaped and sized to the wound bed but are materials not particularly suited for such a purpose considering the applications in question.

The present invention seeks to provide improved wound treatment apparatus.

According to an aspect of the present invention, there is provided a wound dressing for application on a wound bed, the dressing including at least one continuous surface providing a contact surface of the dressing, the contact surface being provided with a pluralities of apertures therein. In use, the dressing is coupled to a vacuum chamber of the apparatus formed by a shroud or cover, the vacuum chamber being connectable to a vacuum source so as to provide a suction through the apertures on application of the vacuum source.

Such a dressing can provide a reliable and substantially even suction force at the wound bed itself. Thus, the wound can be covered by a continuous membrane with openings which all provide suction. The suction provided by the apertures is controllable and, at least in the preferred embodiment, even from aperture to aperture. This is not necessarily the case with the prior art systems, in which parts of the dressings might not provide adequate suction at the wound throughout the dressing area and thus ineffective drainage of exudate and early clogging of those parts of the dressing.

Advantageously, the dressing is conformable, preferably by cutting.

In the preferred embodiment the dressing has a coiled form. With this arrangement, the dressing can be sized by cutting from the outer perimeter of the dressing while leaving intact the inner coiled part of the chamber.

Most preferably, the dressing is in the form of a coiled tubing held in a substantially planar shape, with the surfaces of the tubing forming the contact surface of the dressing.

The tubing may be whole or may be a partial tubing. Particularly where the dressing is made from whole tubing, apertures may he provided on more than just the lower surfaces of the coils of tubing.

The tubing can be held in place by connecting together adjacent surfaces of each coil. Advantageously, the inner end of the coiled tubing is closed, with the outer end providing a coupling to a vacuum source. It will be apparent, however, that in an alternative embodiment the outer end of the coiled tubing could be sealed with the inner end being connected to the low pressure source, in which case there is no need for a nurse or other clinician to make the connection to the vacuum source, merely to close off the outer end of the coiled tubing after cutting it to size the dressing to the wound area. In yet another alternative, both ends of the tubing could be connected to the source of low pressure or both could be closed off with the connection being located elsewhere than at the ends of the tubing. The end or ends could be supplied closed or could be closed by the clinician.

According to another aspect of the present invention, there is provided a wound dressing for application on a wound bed, the dressing including at least one contact surface for application at a wound bed, the dressing having a coiled form and including a plurality of apertures in said contact surface.

Preferably, the dressing is in the form of a coiled whole or partial tubing held in a substantially planar shape, with the surfaces of the tubing forming the contact surface of the dressing.

The dressing may be made of any suitable material, in the preferred embodiments of a polymeric material such as silicone, polyurethane, polyvinyichloride. In other embodiments the dressing could be made from a fabric material or mesh.

It is envisaged that in some embodiments there could be provided at least one reinforcing feature to prevent collapse of the dressing during use.

According to another aspect of the present invention, there is provided a wound treatment system including a dressing as herein specified, a suction overlay member and means to connect to a vacuum source.

Embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawing, in which the sole Figure is a perspective view from below of an embodiment of dressing.

Referring to the Figure, the embodiment of dressing 10 shown is in the form of coils 12 of tubing 14 in a substantially planar arrangement.

The dressing 10 is intended to be placed on a wound bed such that the lower surface of the dressing is placed against the open wound, preferably directly on the wound. The dressing 10 is covered with a vacuum element (not shown) which is operable to create a vacuum over the dressing and in use to provide a suction force through apertures 18 in the dressing 10. This suction force draws exudate from the wound surface to achieve the objectives described, for example, by Chariker el a! in the above-mentioned publication.

The tubing 14 is in this embodiment a half tube, as shown particularly at its outer end 16.

Adjacent coils 12 of the tubing 14 are weakly connected together such that the tubing 14 keeps the arrangement shown but the tubing can be separated, from its outer end 16 for sizing purposes as described below. Suitable means by which adjacent coils are connected together will he apparent to the skilled person and can include, for example, the application of adhesive, plastic welding and so on. One example would be by forming the coil of tubing when still soft/slightly molten allowing them to fuse together to form weak is bonds between adjacent coils.

The tubing 14 is provided with a plurality of apertures 18 such that the lower surface of the dressing 20 has many apertures 18. In this embodiment, apertures are provided even in parts of the tubing 14 which could be described as not being in the lowest surface 20 of the dressing 10, that is the plane on which it sits. Such apertures are useful in sucking up exudate located above such a plane. However, in other embodiments, there may be provided apertures I 8 only at this lowest surface 20.

The tubing 14 is preferably made from a polymeric material, such as silicone, polyurethane or PVC. It could also he made from materials more conventionally used in dressings, such as cotton, and could be in the form of a fabric, mesh or the like. The dressing 10 is preferably flexible so as to conform to the wound surface, thereby to maximise contact at the wound while minimising patient discomfort.

While the dressing 10 can be made to con form to the surfaces at the wound and therefore to fit within the wound itself with the outer coils 14 resting over undamaged skin tissue, it is preferred that the dressing can be cut to size by a nurse so as to fit only in the wound bed. For this purpose, the tubing 14 can be uncoiled from its outer end 16 by pulling apart the weak connections between adjacent coils 12. The tubing 14 can then be uncoiled to the extent necessary to reduced it to the size of the wound bed and the uncoiled tubing cut away, for example with surgical scissors. This is a much simpler arrangement that the cutting of a foam or gauze dressing of the prior art types and does not compromise the effectiveness of the dressing when in use. The reason for this is that the tubing 14 retains is original structure and thus there is no loss of suction through the apertures 18, for

example.

In another embodiment (not shown), the dressing 10 is made from whole tubing rather than the half tubing shown. In this alternative, the tubing may have apertures 18 only on the lower side of the dressing 10 or may have apertures 18 all around. The latter can facilitate production of the dressing.

The vacuum can be applied to the dressing 10 of the above-described embodiments in a variety of ways. For example, with the half-tubing embodiments, a flexible cover or shroud member can be applied over the dressing 10 to contain the suction force required through the apertures 1 8. The cover or shroud would not be needed if the dressing is is submerged in fluid. In the whole tubing embodiments, connections could be made to the outer and/or inner ends of the tubing 14, in which case the tubing 14 itself could be said to provide a vacuum chamber.

These arrangements can provide a controllable vacuum throughout the dressing 10 via control from the vacuum supply itself and thus controlled suction at the wound surface.

Such a vacuum can be adjusted as suited by surgical requirements and can be much more effectively controlled than prior art systems because of the retained integrity of the dressing structure. That is, substantially even vacuum can be generated throughout the area of the dressing and this vacuum can be adjusted quickly and efficiently by adjustment of the vacuum or low pressure source. Such accurate and direct suction control is not possible

with the prior art systems.

Furthermore, the structure of the dressing 10, particularly that of the provision of a continuous dressing surface with apertures therein, provides a reliable suction effect through all the apertures, not only better for wound cleaning but also preventing or reducing premature blocking of the apertures and thus failure of the dressing, particularly compared to the prior art dressings. In particular, the dressing can be designed to allow the passage of granulate of larger size than would be allowed to pass through a typical open cell polymeric foam or gauze.

It will be apparent that the system would be provided with a suction cover over the whole dressing and wound area of the type described in the above-mentioned two references.

[he number of apertures 18 and their size will primarily be dependant upon application and could be produced specifically for a particular application. Alternatively, there could he provided a plurality of different dressing types, that is with different numbers and sizes of apertures, selectable by the clinician on the basis of the wound type and behaviour.

In some embodiments it may be desired to provide reinforcing elements in the tubing 14, preferably internal to the tubing itself. Such reinforcing elements can prevent collapse of the tubing in those cases where its structure or the materials used may make it prone to such collapse when empty or partially full. Collapse is not to be confused with flexibility of the tubing for coiling purposes and also for patient comfort purposes.

The structure of the dressing 10 allows the creation of dressing areas providing different suction effects. For example, the number of apertures 18 can be varied in the tubing to provide greater suction in some areas relative to others. Additionally or alternatively, the sizes of the apertures 1 8 can be varied. In another embodiment, the internal structure of the dressing 10, that is of the tubing 14, can be varied. For example the internal diameter of the tubing can he altered to alter the suction at various points in the tubing 14.

Although the preferred embodiments use a structure formed from tubing, alternatives are possible. For example, the dressing could be provided with a lower apertured surface and a coiled upstanding wall extending from that surface. The coiled wall will provide the spiral structure of the embodiment shown in the Figure and also a structure which can be sized by cutting from the outer perimeter of the dressing, in similar manner to the above-described embodiments.

The overall geometry of the coil could be fashioned to fit irregularly shaped wounds. For example, an oval or roughly square wound can be accommodated.

Moreover, the dressing need not be generally planar. For example, it could be curved, such as a spinal cone, to accommodate deeper wounds.

Claims

1. A wound suction dressing for application on a wound bed, the dressing including at least one continuous surface providing a contact surface of the dressing, the contact surface being provided with a pluralities of suction apertures therein.

2. A wound suction dressing according to claim I, including a vacuum chamber connectable to a vacuum source so as to provide a suction at the apertures.

3. A wound suction dressing according to claim I or 2, wherein the dressing is conformable.

4. A wound suction dressing according to claim 3, wherein the dressing is conformable by cutting.

5. A wound suction dressing according to any preceding claim, wherein the dressing has a coiled form.

6. A wound suction dressing according to claim 5, wherein the dressing is in the form of a coiled tubing.

7. A wound suction dressing according to claim 6, wherein the surfaces of the tubing forming a lower or application surfiice of the dressing are provided with a plurality of said apertures.

8. A wound suction dressing according to claim 6 or 7, wherein the tubing is whole or a partial tubing.

9. A wound suction dressing according to any one of claims 5 to 8, wherein the coil is separable and severable.

10. A wound suction dressing according to any one of claims 5 to 9, wherein one or both of the coil ends is closed.

11. A wound suction dressing according to any one of claims 5 to 9, wherein one or both of the coil ends is connectable to a vacuum source.

12. A wound suction dressing according to any preceding claim, wherein apertures are provided on more than just said at least one continuous surface of the dressing.

13. A wound suction dressing according to any preceding claim, wherein the dressing is substantially planar.

14. A wound suction dressing for application on a wound bed, the dressing including at least one contact surface for application at a wound bed, the dressing having a coi!ed form and including a plurality of apertures in said contact surface.

15. A wound suction dressing according to claim 14, wherein the dressing is in the form of a coiled whole or partial tubing held in a substantially planar shape, with the surfaces of the tubing forming the application surface of the dressing.

16. A wound suction dressing according to any preceding claim, wherein the dressing is made of a polymeric material.

17. A wound suction dressing according to claim 16, wherein the dressing is made from silicone, polyurethane or polyvinyichloride.

18. A wound suction dressing according to any preceding claim, wherein the dressing is made from a fabric material or mesh.

19. A wound suction dressing according to any preceding claim, including at least one reinforcing feature to prevent collapse of the dressing during use.

20. A wound treatment system including a dressing according to any preceding claim, a suction overlay member and means to connect to a vacuum source.