Device and method for wound therapy

• US 7,615,036 B2
• Filed: 05/11/2006
• Issued: 11/10/2009
• Est. Priority Date: 05/11/2006
• Status: Active Grant

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Kalypto Medical, Inc. (Smith & Nephew PLC)
• Inventors: Gordon, John Howard, Joshi, Ashok V., Bhavaraju, Sai, Dayton, Troy C.
• Primary Examiner(s): Kidwell; Michele
• Assistant Examiner(s): Treyger; Ilya Y
• Application Number:
  US11/432,855
• Publication Number:
  US 20070265585A1
• Time in Patent Office: 1,279 Days
• Field of Search: 604304-307, 604/313, 604/315, 604/316, 604/317, 604/541, 604/543, 602/42, 602/43, 602/46
• US Class Current: 604/313
• CPC Class Codes: A61M 1/602 Mechanical means for preventing flexible containers from collapsing when vacuum is applied inside, e.g. stents
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/882 Draining devices provided with means for releasing antimicrobial or gelation agents in the drained fluid
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/962 having pumping means on the suction site, e.g. miniature pump on dressing or dressing capable of exerting suction
• CPC Class Codes: A61M 1/964 having venting means on or near the dressing
• CPC Class Codes: A61M 1/982 with means for detecting level of collected exudate
• CPC Class Codes: A61M 2205/7536 allowing gas passage, but preventing liquid passage, e.g. liquophobic, hydrophobic, water-repellent membranes
• CPC Class Codes: A61M 27/00 Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202

Abstract

A wound therapy device is disclosed. The wound therapy device may include a housing for covering at least a portion of a wound and for sealing to a body surface of a patient. The housing may also include a liquid-retention chamber for retaining liquid therein and a vacuum connection for coupling to a vacuum source. The vacuum connection may be in gaseous communication with the liquid-retention chamber. The vacuum connection may be separated from the liquid-retention chamber by a liquid barrier.

Claims

1. A wound therapy device, comprising:

a housing to cover at least a portion of a wound site;

a liquid retention chamber position within the housing, wherein the liquid retention chamber collects and stores at least one of liquid exudate and bodily fluid from the wound site, and, wherein the liquid retention chamber retains the collected liquid exudate and bodily fluid stored therein upon application of negative pressure thereto;

an opening in the housing operatively associated with a vacuum source for creating negative pressure within at least the liquid retention chamber; and

,

a gas permeable liquid barrier associated with the housing for precluding migration of the liquid exudate and bodily fluid into and through the opening and into the vacuum source.

2. The wound therapy device of claim 1, further comprising a seal for sealing the housing to a body surface of a patient.

3. The wound therapy device of claim 1, wherein the housing is constructed of a material having a rigidity sufficient to prevent significant collapse of the liquid retention chamber when subject to a pressure lower than atmospheric pressure.

4. The wound therapy device of claim 3, wherein the housing material is chosen from a rigid plastic, semi rigid plastic, rigid rubber, semi rigid rubber and combinations thereof.

5. The wound therapy device of claim 1, wherein the housing comprises a flexible baffler.

6. The wound therapy device of claim 1, further comprising:

structural supports to prevent significant collapse of the liquid-retention chamber when subject to a pressure lower than atmospheric pressure.

7. The wound therapy device of claim 6, wherein the structural supports provide support to the housing, and the structural supports are chosen from:

customizable rigid and customizable semi-rigid structural supports.

8. The wound therapy device of claim 1, further comprising structural foam within the liquid-retention chamber to prevent significant collapse of the liquid-retention chamber when subject to a pressure lower than atmospheric pressure.

9. The wound therapy device of claim 1, wherein the liquid baffler is chosen from:

porous polytetrafluoroethylene, microporous polytetrafluoroethylene, porous polypropylene, microporous polypropylene, porous polyethylene, microporous polyethylene, and combinations thereof.

10. The wound therapy device of claim 1, wherein the liquid barrier is a labyrinth.

11. The wound therapy device of claim 1, wherein the liquid barrier is a droplet gap.

12. The wound therapy device of claim 1, wherein the liquid retention chamber further comprises a porous structure for retaining liquid.

13. The wound therapy device of claim 12, wherein the porous structure is chosen from:

a sponge, packing material, a gelling agent, a super-absorbent polymer material and combinations thereof.

14. The wound therapy device of claim 1, wherein the liquid retention chamber further comprises an antimicrobial agent.

15. The wound therapy device of claim 1, wherein the opening comprises a vacuum port configured to be coupled to a vacuum supply line.

16. The wound therapy device of claim 1, wherein the opening is coupled to a micro-vacuum pump disposed adjacent the wound.

17. The wound therapy device of claim 1, further comprising a pressure relief valve to maintain pressure within the housing.

18. The wound therapy device of claim 17, wherein the pressure relief valve further comprises an inflow filter.

19. The wound therapy device of claim 1, wherein a pressure inside the housing is controlled by a switch that deactivates the vacuum source below a lower negative pressure threshold.

20. The wound therapy device of claim 19, wherein the switch further activates the vacuum source above an upper negative pressure threshold.

21. The wound therapy device of claim 1, further comprising a fill indicator.

22. The wound therapy device of claim 21, wherein the fill indicator provides a signal that prompts a deactivation of the vacuum source.

23. The wound therapy device of claim 1, further comprising an overflow valve.

24. The wound therapy device of claim 1, wherein the housing is constructed of plastic chosen from:

polypropylene, polyurethane, polyvinyl chlorides, polyethylene, acrylonitrile copolymers, nylon, polyester, polychlorotrifluoroethylene, fluoropolymer, and polytetrafluoroethylene and combinations thereof.

25. The wound therapy device of claim 1, further comprising a wound interface layer.

26. The wound therapy device of claim 25, wherein the wound interface layer comprises multiple layers.

27. The wound therapy device of claim 25, wherein the wound interface layer is configured to be disposed adjacent the wound.

28. The wound therapy device of claim 25, wherein the wound interface layer is at least one of the following:

a degradable copolymer foil, dermal regeneration templates, bioabsorbable gels, bioabsorbable foams, tissue adhesion prevention bafflers, a skin substitute, a layer that selectively maintains moisture, an angiogenic layer, and an antimicrobial layer.

29. The wound therapy device of claim 1, wherein the housing is semi-permeable.

30. The wound therapy device of claim 29, wherein the semi-permeable housing has a water vapor transmission rate of greater than about 836/m²day.