Device and method for wound therapy

• US 20070265585A1
• Filed: 05/11/2006
• Published: 11/15/2007
• Est. Priority Date: 05/11/2006
• Status: Active Grant

• Current Assignee: Smith+Nephew, Inc.
• Original Assignee: Kalypto Medical, Inc. (Smith & Nephew PLC)
• Inventors: Gordon, John, Bhavaraju, Sai, Joshi, Ashok, Dayton, Troy
• Granted Patent: US 7,615,036 B2
• Time in Patent Office: Days
• 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 configured to cover at least a portion of a wound;

a liquid-retention chamber positioned inside of the house; and

a vacuum connection for coupling to a vacuum source, the vacuum connection is gaseous communication with the liquid-retention chamber, the vacuum connection being separated from the liquid-retention chamber by a liquid barrier.

2. The wound therapy device of claim 1, further comprising a deal 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 then atmosphere 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 barrier.

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 then the atmosphere 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 atmosphere pressure.

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

porous polytetrafluoroethylene, microporous, polytetrafluorothylene, 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 2, 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 vacuum connection comprises a vacuum port configured to be coupled to a vacuum supply line.

16. The wound therapy device of claim 1, wherein the vacuum connection 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 at a therapeutic value at a wound site.

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 about 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, polyvinyl chlorides, polyethlene, 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 barriers, a skin substitute, a layer that selectively maintains moisture, an angiogenic later, and an antimicrobial layer.

39. The wound therapy device of claim 1, wherein the vacuum connection is coupled to an electro-osmotic pump disposed adjacent the wound.

40. The wound therapy device of claim 1, wherein the vacuum connection is coupled to an osmotic pump disposed adjacent the wound.

29. The wound therapy device of claim, 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/m² day.

33. The wound therapy device of claim 30, further comprising:

a wound interface module to be placed in contact with the wound site, the wound interface module in communication with the liquid-retention module; and

a vacuum pump module in communication with the liquid-retention module via the passage.

34. The wound therapy device of claim 33, wherein the wound interface module, the liquid-retention module and the vacuum pump module are each separately replaceable.

35. The wound therapy device of claim 33, wherein the wound interface module, the liquid-retention module and the vacuum pump module are configured to be disposed adjacent the wound site.

31. A wound therapy device, comprising:

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

a liquid-retention chamber configured to retain exudate from the wound site adjacent the wound site; and

a passage through which negative pressure is applied to the wound sire whole exudate is maintained within the liquid-retention chamber.

32. The wound therapy device of claim 31, wherein the device is modular and the liquid-retention chamber is a component of liquid-retention module.

36. A wound therapy device, comprising:

a substantially liquid impermeable housing, comprising;

a liquid-retention chamber;

a vacuum connection for coupling to a vacuum source, the vacuum connection is gaseous communication with the liquid-retention chamber, the vacuum connection being separated from the liquid-retention chamber by means for preventing liquid droplets from passing; and

means for preventing collapse of the liquid-retention chamber when subject to a vacuum.

37. The wound therapy device of claim 36, wherein the means for preventing liquid droplets from passing is at least one of the following:

a porous hydrophobic film, a microporous hydrophobic film, a structure comprising hydrophobic fibers, a droplet gap, and a liquid labyrinth.

38. The wound therapy device of claim 36, wherein the means for preventing collapse of the liquid-retention chamber is at least one of the following:

a material of the liquid impermeable housing having a rigidity sufficient to withstand a vacuum, structural supports having a rigidity sufficient to provide support to the liquid impermeable housing under a vacuum, and a structural foam disposed within the liquid-retention chamber.