Device and method for wound therapy

• US 8,460,255 B2
• Filed: 11/18/2009
• Issued: 06/11/2013
• 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: Joshi, Ashok V., Gordon, John Howard, Bhavaraju, Sai, Dayton, Troy C., Heiser, Jeremy
• Primary Examiner(s): Zalukaeva, Tatyana
• Assistant Examiner(s): TREYGER, ILYA Y
• Application Number:
  US12/592,049
• Publication Number:
  US 20100100063A1
• Time in Patent Office: 1,301 Days
• Field of Search: 604/313, 604/315, 604/316, 604/317
• US Class Current: 604/313
• 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 13/0213 the fluid retention member being a layer of hydrocolloid, gel forming material
• CPC Class Codes: A61F 13/0243 characterised by the properties of the skin contacting layer, e.g. air-vapor permeability
• 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: A61L 15/28 Polysaccharides or their derivatives A61L15/225 takes precedence
• CPC Class Codes: A61L 15/425 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 15/58 Adhesives
• CPC Class Codes: A61L 15/60 Liquid-swellable gel-forming materials, e.g. super-absorbents
• CPC Class Codes: A61M 1/73 comprising sensors or indicators for physical values
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/743 by changing the cross-section of the line, e.g. flow regulating valves A61M1/7413 takes precedence
• 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 1/784 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 1/90 Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing
• 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 2205/13 with means for the detection of operative contact with patient, e.g. lip sensor
• CPC Class Codes: A61M 2205/15 : Detection of leaks
• CPC Class Codes: A61M 2205/7509 : for virus
• CPC Class Codes: A61M 2205/7518 : bacterial
• 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 collector 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 collector. The vacuum connection may be separated from the liquid collector by a liquid barrier.

Claims

1. A wound therapy device, comprising:

a wound cover configured to cover at least a portion of a wound;

a vacuum source configured to be in fluid communication with the wound cover;

a liquid-retaining structure integrated with and positioned under the wound cover, wherein said liquid-retaining structure is configured to collect and retain substantially all liquid wound exudate that enters into the liquid-retaining structure while simultaneously communicating negative pressure generated by the vacuum source to the wound; and

a liquid barrier configured to substantially block liquid flow from out of the liquid-retaining structure.

2. The wound therapy device of claim 1, wherein the liquid-retaining structure comprises a porous material defining a plurality of passages to allow fluid communication between the vacuum source and the wound through the liquid-retaining structure.

3. The wound therapy device of claim 2, wherein the liquid-retaining structure is sufficiently rigid to allow fluid communication between the vacuum source and the wound through the liquid-retaining structure when the device is subject to a pressure lower than atmospheric pressure.

4. The wound therapy device of claim 2, wherein the wound cover is sufficiently rigid to allow fluid communication between the vacuum source and the wound through the liquid-retaining structure when the device is subject to a pressure lower than atmospheric pressure.

5. The wound therapy device of claim 2, wherein the wound cover in combination with the liquid-retaining structure is sufficiently rigid to allow fluid communication between the vacuum source and the wound through the liquid-retaining structure when the device is subject to a pressure lower than atmospheric pressure.

6. The wound therapy device of claim 1, wherein the liquid-retaining structure is configured to retain liquid under a predetermined amount of mechanical force applied to the liquid-retaining structure.

7. The wound therapy device of claim 1, wherein the vacuum source is internal to the wound cover.

8. The wound therapy device of claim 1, wherein the vacuum source is external to the wound cover.

9. The wound therapy device of claim 1, further comprising a vacuum chamber in fluid communication with the vacuum source.

10. The wound therapy device of claim 1, further comprising a liquid-retention chamber.

11. The wound therapy device of claim 10, wherein the liquid-retaining structure is positioned within the liquid-retention chamber.

12. The wound therapy device of claim 11, wherein the liquid retention chamber is sufficiently rigid to allow fluid communication between the vacuum source and the wound through the liquid-retaining structure when the device is subject to a pressure lower than atmospheric pressure.

13. The wound therapy device of claim 10, wherein the liquid-retention chamber extends from within a wound perimeter to a position outside the wound perimeter.

14. The wound therapy device of claim 1, wherein the wound cover comprises a first portion configured to cover at least a portion of the wound, and a second portion configured to be outside a wound perimeter.

15. The wound therapy device of claim 14, wherein the vacuum source is attached to the wound cover adjacent the second portion.

16. The wound therapy device of claim 14, wherein the vacuum source is attached to the wound cover adjacent the first portion.

17. The wound therapy device of claim 1, further comprising means for maintaining operation of the device independent of device orientation.

18. The wound therapy device of claim 1, wherein the vacuum source comprises a power supply.

19. The wound therapy device of claim 1, wherein the wound cover comprises one of the group consisting of polystyrene, polyester, polyether, polyethylene, silicone, neoprene, and combinations thereof.

20. The wound therapy device of claim 1, wherein the wound cover comprises a flexible barrier.

21. The wound therapy device of claim 20, wherein the flexible barrier comprises polyurethane.

22. The wound therapy device of claim 1, further comprising a seal for attaching the device to a surface.

23. The wound therapy device of claim 1, further comprising a skin protection layer for protecting a user'"'"'s skin.

24. The wound therapy device of claim 1, further comprising a vacuum disperser in communication with the liquid-retaining structure.

25. The wound therapy device of claim 1, further comprising a moisture disperser in communication with the liquid-retaining structure.

26. The wound therapy device of claim 1, wherein the liquid-retaining structure comprises one of the group consisting of sponges, fibers, fabrics, gauzes, absorbent material, adsorbent material, polymers, gels, gelling agents, foams, packing material, and combinations thereof.

27. The wound therapy device of claim 1, wherein the liquid-retaining structure further comprises an antimicrobial agent.

28. The wound therapy device of claim 1, wherein the liquid barrier comprises a gas permeable membrane.

29. The wound therapy device of claim 1, wherein the liquid barrier comprises a hydrophobic structure.

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

31. The wound therapy device of claim 30, wherein the wound interface comprises one of the group consisting of a sheet, foam, gel, gauze, a porous matrix, a honeycomb, a mop, confetti, a self-contained tubular structure, and combinations thereof.

32. The wound therapy device of claim 30, wherein the wound interface layer comprises an antimicrobial agent.

33. The wound therapy device of claim 30, wherein the wound interface layer comprises a surface in contact with the wound, said surface comprising at least one pore larger than about 100 microns in diameter.

34. The wound therapy device of claim 1, further comprising an outlet to allow the vacuum source to vent.

35. The wound therapy device of claim 34, wherein the outlet comprises a filter.

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

37. The wound therapy device of claim 1, further comprising means for controlling pressure within the wound cover.

38. The wound therapy device of claim 37, wherein in the means for controlling pressure within the wound cover comprises a pressure sensor.

39. The wound therapy device of claim 1, further comprising a gas sensor.

40. The wound therapy device of claim 1, further comprising an oxygen sensor.

41. The wound therapy device of claim 1, further comprising a temperature sensor.

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

43. The wound therapy device of claim 42, wherein the fill indicator comprises a moisture detector.

44. The wound therapy device of claim 42, wherein the fill indicator comprises an electrical conductivity detector.

45. The wound therapy device of claim 22, further comprising leak detector in operable communication with the seal.

46. The wound therapy device of claim 1, further comprising a blood detector.

47. The wound therapy device of claim 1, wherein the device is conformable for use with wounds in various locations.

48. The wound therapy device of claim 1, wherein the liquid barrier is disposed underneath the wound cover.

49. A wound therapy device, comprising:

a wound cover configured to cover at least a portion of a wound;

a vacuum connection configured to connect the wound cover to a vacuum pump;

a liquid retention chamber under the wound cover and integrated with the wound cover, wherein said liquid retention chamber is configured to collect and retain liquid wound exudate under the wound cover while simultaneously communicating negative pressure generated by the vacuum source to the wound; and

a liquid barrier disposed between the vacuum connection and liquid retention chamber configured to substantially block liquid from the liquid retention chamber from traveling to the vacuum connection.

50. The wound therapy device of claim 49, wherein the liquid barrier is positioned underneath the wound cover.

51. The wound therapy device of claim 49, wherein the liquid barrier comprises a porous hydrophobic material.

52. The wound therapy device of claim 49, wherein the liquid retention chamber comprises a structure and/or substance to assist in retaining liquid drawn into the chamber.

53. The wound therapy device of claim 52, wherein the structure and/or substance is selected from the group consisting of sponges, wicking fibers, fabrics, gauzes;

super-absorbent material, super-absorbent polymers, gels, absorbent foams and gelling agents.

54. The wound therapy device of claim 52, further comprising a porous material positioned within the liquid retention chamber.

55. The wound therapy device of claim 49, further comprising an adapter that connects a vacuum connection tube to the wound cover.

56. The wound therapy device of claim 49, wherein the wound cover is flexible.

57. The wound therapy device of claim 49, wherein the wound cover is semi-rigid.

58. The wound therapy device of claim 49, wherein the wound cover is substantially impermeable to liquids but at least partially permeable to water vapor and other gases.

59. The wound therapy device of claim 49, further comprising a wound interface layer.

60. The wound therapy device of claim 49, further comprising an adhesive film configured to seal the wound cover to a patient.

61. The wound therapy device of claim 49, further comprising a vacuum source configured to provide vacuum through the vacuum connection to the wound through the wound cover.