VACUUM ASSISTED WOUND DRESSING

• US 20110009838A1
• Filed: 11/20/2008
• Published: 01/13/2011
• Est. Priority Date: 11/21/2007
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Greener, Bryan
• Granted Patent: US 8,715,256 B2
• Time in Patent Office: Days
• US Class Current: 604/319
• CPC Class Codes: A61F 13/0206 with absorbent fibrous layers, e.g. woven or non-woven absorbent pads or island dressings
• CPC Class Codes: A61F 13/0209 comprising superabsorbent material
• CPC Class Codes: A61F 13/0226 characterised by the support layer
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61F 2013/0094 for sensing physical parameters
• CPC Class Codes: A61M 1/78 Means for preventing overflow or contamination of the pumping systems combined with drainage containers A61M1/60
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/964 having venting means on or near the dressing
• CPC Class Codes: A61M 1/985 the dressing itself forming the collection container
• CPC Class Codes: A61M 39/24 Check- or non-return valves

Abstract

Apparatus for the application of topical negative pressure therapy to a wound site is described, the apparatus comprising: a wound contacting element for retaining wound exudate fluid therein; a wound covering element that provides a substantially airtight seal over the wound contacting element and wound site; a vacuum connection tube connecting a wound cavity to a vacuum source; and a vacuum source connected to a distal end of the vacuum connection tube.

Claims

1. Apparatus for the application of topical negative pressure therapy to a wound site, the apparatus comprising:

a wound contacting element for retaining wound exudate fluid therein;

a wound covering element that provides a substantially airtight seal over the wound contacting element and wound site;

a vacuum connection tube connecting a wound cavity to a vacuum source; and

a vacuum source connected to a distal end of the vacuum connection tube.

2. Apparatus according to claim 1 wherein the wound contacting element blocks liquid transport beyond itself under pressures between atmospheric pressure and 200 mmHg below atmospheric pressure.

3. Apparatus according to claim 2 where the wound contacting element blocks liquid transport beyond itself between atmospheric and 250 mmHg below atmospheric pressure.

4. Apparatus according to any one preceding claim wherein liquid transport out of the wound cavity is blocked by closing of a liquid contact triggered valve located between the wound contacting element and the vacuum connection tube.

5. Apparatus according to any one of preceding claims 1 to 3 wherein liquid transport is blocked by the wound contacting element being able to absorb but not transmit liquid under the applied negative pressure.

6. An apparatus according to claim 5 wherein the wound contacting element is a self-coalescent material.

7. An apparatus according to claim 6 where the self-coalescent material is selected from the group comprising:

carboxymethylchitosan; and

a derivative of carboxymethylchitosan.

8. An apparatus according to claim 4 wherein the liquid contact-triggered valve is constructed of an absorbent material placed in a restricted aperture.

9. An apparatus according to claim 8 wherein the absorbent material is able to absorb but not transmit fluid under the applied negative pressure.

10. An apparatus according to any of the claims 1-9 wherein the coupling of the vacuum connection tube to the wound cavity is achieved via an aperture in the wound covering element.

11. An apparatus according to claim 10 wherein the aperture in the wound covering element has a pressure-sensitive valve.

12. An apparatus according to claim 11 wherein the pressure sensitive valve opens when a surface-to-surface pressure differential of 5 to 200 mmHg exists.

13. An apparatus according to any of the claims 1-12 wherein coupling of the vacuum connection tube to the wound covering element is by non-adhesive means.

14. An apparatus according to claim 13 wherein coupling is achieved by a surface-to-surface pressure differential.

15. An apparatus according to claim 1 wherein the wound contacting element and the wound covering element are combined in a single physical entity.

16. An apparatus according to claim 1 wherein the wound contacting element, the wound covering element and the vacuum connection tube are combined into a single physical entity.

17. Apparatus for the application of topical negative pressure therapy to a wound site substantially as hereinbefore described with reference to the accompanying description and drawings.

18. Apparatus for the application of topical negative pressure therapy to a wound site, the apparatus comprising:

a wound covering element that provides a substantially airtight seal over the wound site;

a vacuum connection tube connecting the wound covering element to a vacuum source;

a vacuum source connected to a distal end of the vacuum connection tube;

the wound covering element having valve means associated therewith which permits only fluid flow out of a wound cavity defined by the wound covering element and the wound.

19. Apparatus according to claim 18 wherein said valve means is a self-closing one-way valve.

20. Apparatus according to either claim 18 or 19 wherein the valve means is in an aperture formed in the wound covering element.

21. Apparatus according to any one of claims 18 to 21 wherein the valve means is a pressure sensitive valve.

22. An apparatus according to claim 21 wherein the pressure sensitive valve opens when a surface-to-surface pressure differential of 5 to 200 mmHg exists.

23. An apparatus according to any of claims 19 to 22 wherein coupling of the vacuum connection tube to the wound covering element is by non-adhesive means.

24. An apparatus according to claim 23 wherein coupling is achieved by a surface-to-surface pressure differential.

25. Apparatus according to claim 24 wherein the vacuum connection tube may be repeatedly connected and disconnected from the wound covering element without damage thereto.