Wound cleansing apparatus in-situ

• US 8,080,702 B2
• Filed: 08/02/2010
• Issued: 12/20/2011
• Est. Priority Date: 10/28/2003
• Status: Active Grant

• Current Assignee: Smith & Nephew PLC
• Original Assignee: Smith & Nephew PLC
• Inventors: Blott, Patrick Lewis, Greener, Bryan, Hartwell, Edward Yerbury, Nicolini, Derek, Walker, Tina Michelle, Lee-Webb, Julian
• Primary Examiner(s): Bianco, Patricia
• Application Number:
  US12/848,817
• Publication Number:
  US 20100298793A1
• Time in Patent Office: 505 Days
• Field of Search: 602 41- 43, 424443-449, 424/78.05, 424/78.06, 424/78.07, 604/304, 604/307, 604/289, 604/313, 604/78.05, 604/78.06, 604/78.07
• US Class Current: 602/41
• 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 13/0259 characterised by the release liner covering the skin adhering 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 2013/00357 implanted wound fillings or covers
• CPC Class Codes: A61M 1/75 Intermittent or pulsating suction A61M1/63, A61M1/772 take precedence
• CPC Class Codes: A61M 1/77 Suction-irrigation systems aspiration tips supplying fluids A61M1/85; specific for negative pressure wound therapy A61M1/92; combined with tracheal tubes A61M16/0463
• CPC Class Codes: A61M 1/772 operating alternately
• CPC Class Codes: A61M 1/81 Piston pumps, e.g. syringes
• CPC Class Codes: A61M 1/82 Membrane pumps, e.g. bulbs
• CPC Class Codes: A61M 1/85 with gas or fluid supply means, e.g. for supplying rinsing fluids or anticoagulants for negative pressure wound therapy A61M1/92, A61M1/94; combined with tracheal tubes A61M16/0463; dental instruments with combined rinsing and aspirating A61C17/0208
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/916 specially adapted for deep wounds
• CPC Class Codes: A61M 1/92 with liquid supply means
• 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 1/985 the dressing itself forming the collection container
• CPC Class Codes: A61M 2205/075 Bulb type
• CPC Class Codes: A61M 2205/106 reciprocating
• CPC Class Codes: A61M 2205/7518 bacterial
• CPC Class Codes: A61M 2205/8206 battery-operated
• 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
• CPC Class Codes: A61M 3/0216 : Pressure
• CPC Class Codes: A61M 3/022 : Volume; Flow rate
• CPC Class Codes: A61M 3/0229 : Devices operating in a closed circuit, i.e. recycling the irrigating fluid
• CPC Class Codes: A61M 35/30 : Gas therapy for therapeutic treatment of the skin
• CPC Class Codes: Y10T 29/49826 : Assembling or joining

Abstract

An apparatus for cleansing wounds, in which wound exudate is removed from a wound bed and selectively cleansed and returned to the wound. The cleansing means removes materials deleterious to wound healing, and the cleansed fluid, still containing materials that are beneficial in promoting wound healing, is returned to the wound bed. The associated wound dressing and cleansing means are conformable to the wound, and may have irrigant fluid circulated from a reservoir by a device for moving fluid through a flow path which passes through the dressing and a means for fluid cleansing and back to the dressing.

Claims

1. A wound dressing apparatus, which comprises:

a wound dressing including a backing layer for positioning over a wound area; and

a negative pressure system comprising;

a miniature pump for applying negative pressure to the wound dressing to move wound exudate from the wound area, the miniature pump being integral with and mounted to the backing layer of the dressing; and

a pressure control device configured to control or vary the pressure under the backing layer applied by the pump in response to a pressure detected underneath the backing layer.

2. The wound dressing apparatus of claim 1, wherein the wound dressing comprises:

a film positionable adjacent to the wound area, an absorbent member positioned adjacent the film, and a top member.

3. The wound dressing apparatus of claim 2, further comprising an adhesive film, the adhesive film adapted to secure the wound dressing in place and to provide a fluid-tight seal between the wound dressing and the wound area.

4. The wound dressing apparatus of claim 2, further comprising a chamber including at least one of medicaments, anti-infectives, anti-inflammatory agents, anti-oxidants, protease inhibitors, vitamins, ion exchangers, and pH adjusting agents.

5. The wound dressing apparatus of claim 2, wherein the absorbent member comprises a material selected from the group consisting of foams, hydrophilic polymeric materials, and hydrophobic materials.

6. The wound dressing apparatus of claim 2, wherein the absorbent member includes at least one of medicaments, anti-infectives, anti-inflammatory agents, anti-oxidants, protease inhibitors, vitamins, ion exchangers, and pH adjusting agents.

7. The wound dressing apparatus of claim 1, wherein the pump is adapted to apply negative pressure of up to 114 mmHg.

8. The wound dressing apparatus of claim 1, wherein the pump is adapted to apply negative pressure of up to 380 mmHg.

9. The wound dressing apparatus of claim 1, wherein the pump includes a battery for powering the pump, the battery adapted to be mounted to the backing layer.

10. The wound dressing apparatus of claim 1, wherein the backing layer comprises a transparent or translucent material.

11. The wound dressing apparatus of claim 1, wherein the wound dressing includes a bleed valve adapted to respond to a degree of pressure in the wound dressing.

12. The wound dressing apparatus of claim 1, wherein the wound dressing includes a bleed valve adapted to respond to a degree of exudate build-up in the wound dressing.

13. A negative pressure wound therapy system comprising:

a backing layer having a proximal, wound-facing face, the proximal, wound-facing face bearing an adhesive thereon;

a permeable polymer film on a proximal side of the backing layer configured to allow wound exudate to move through the film into a chamber between the backing layer and the permeable polymer film;

a permeable integer on a distal side of the chamber configured to retain said wound exudate within the space; and

a vacuum source in fluid communication with the backing layer configured to draw wound exudate through the permeable polymer film into the chamber.

14. The system of claim 13, comprising a resiliently flexible chamber positioned between the backing layer and the permeable polymer film and configured to sequester wound exudate during operation of the vacuum source.

15. The system of claim 14, wherein the chamber comprises foam.

16. The system of claim 14, wherein the chamber comprises a sorption unit.

17. The system of claim 14, wherein the chamber comprises an array with spaces therebetween.

18. The system of claim 13, wherein the permeable integer is a filter.

19. The system of claim 13, further comprising an additional adhesive configured to secure the edge of a wound to a portion of the backing layer.

20. The system of claim 13, wherein the system is disposable after use.

21. The system of claim 13, wherein the vacuum source is battery-powered.

22. The system of claim 13, wherein the vacuum source comprises a piezoelectric transducer.

23. An apparatus for the treatment of a wound, comprising:

a backing layer configured to be positioned over at least a portion of the wound;

a porous layer configured to be positioned between the wound and the backing layer to define a space beneath the backing layer and an upper surface of the porous layer;

a filter configured to retain wound exudate in the space between the porous layer and the backing layer; and

,

a vacuum source for applying vacuum to the wound to draw wound exudate into the space between the porous layer and the backing layer.

24. The apparatus of claim 23, wherein the space beneath the backing layer additionally comprises a resiliently-flexible filler.

25. The apparatus of claim 24, wherein the filler comprises foam.

26. The apparatus of claim 25, wherein the foam is a reticulated polyurethane foam.

27. The apparatus of claim 23, wherein the vacuum source is a pump.

28. The apparatus of claim 27, wherein the pump is mounted on the backing layer.

29. The apparatus of claim 23, wherein the filter is hydrophobic.

30. The apparatus of claim 23, wherein the filter comprises a flat polymeric material.

31. The apparatus of claim 23, wherein the filter comprises a micropore filter.

32. The apparatus of claim 23, further comprising a conduit for applying negative pressure from the vacuum source to the backing layer.

33. The apparatus of claim 23, wherein the backing layer is flexible.

34. The apparatus of claim 23, wherein the backing layer is attached to the porous layer.

35. A wound dressing apparatus, comprising:

a wound dressing including an absorbent member positionable relative to a wound area, the absorbent member being disposed underneath a backing layer; and

a negative pressure system mounted on the wound dressing, the negative pressure system including;

a miniature pump for applying negative pressure to the wound area to facilitate removal of wound exudate from the wound area, the miniature pump being integral with and mounted to the wound dressing,

a pressure control device configured to control or vary the pressure under the backing layer applied by the pump in response to a pressure detected underneath the backing layer.

36. The wound dressing apparatus of claim 35, wherein the pump includes a battery for powering the pump.

37. A method of treating a wound comprising:

positioning a wound dressing over the wound, the wound dressing comprising;

a backing layer having a proximal, wound-facing side; and

a permeable polymer film on a proximal side of the backing layer and defining a space between the backing layer and the permeable polymer film;

sealing the wound dressing to a region of skin surrounding the wound so as to create a substantially fluid-tight seal;

applying negative pressure to the wound dressing with a source of negative pressure to draw wound exudate through the permeable polymer film into the space; and

retaining wound exudate in the space while negative pressure is being applied.

38. The method of claim 37, further comprising sequestering wound exudate in the space with a resiliently flexible filler.

39. The method of claim 38, wherein the resiliently flexible filler comprises foam.

40. The method of claim 37, further comprising positioning a filter between the space and the source of negative pressure to retain wound exudate in the space while negative pressure is being applied.

41. The method of claim 37, where the permeable polymer film is attached to the proximal side of the backing layer.

42. The method of claim 37, wherein wound exudate is sequestered using a sorption unit.

43. The method of claim 37, wherein the negative pressure is applied with a battery-powered source of negative pressure.

44. The method of claim 37, further comprising sealing the backing layer to the region of skin surrounding the wound with a supplemental adhesive.

45. The method of claim 40, wherein the filter comprises part of the wound dressing.

46. A negative pressure wound therapy system comprising:

a negative pressure pump;

a wound dressing comprising;

a resiliently deformable backing layer having a proximal, wound-facing face, the proximal, wound-facing face bearing an adhesive film thereon for adhering the backing layer to skin surrounding a wound;

a resiliently flexible chamber configured to be positioned beneath the backing layer on a proximal side of the backing layer and configured to sequester wound exudate during application of negative pressure;

a permeable membrane on a distal side of the chamber adjacent the backing layer configured to retain said wound exudate within the chamber; and

a permeable polymer film on a proximal side of the chamber adjacent the wound configured to pass wound exudate through the film into the chamber; and

a tube configured to supply negative pressure from the pump through the backing layer to the wound.

47. The system of claim 46, wherein the dressing is disposable after use.

48. The system of claim 46, wherein the chamber comprises an array with spaces therebetween.

49. The system of claim 46, wherein the chamber comprises foam.

50. The system of claim 46, wherein the pump is battery-powered.

51. The system of claim 46, wherein the permeable membrane is a filter.

52. A method of treating a wound comprising:

positioning a wound dressing over the wound, the wound dressing comprising;

a backing layer;

a porous layer beneath the backing layer;

a resiliently-flexible filler located in a space between the backing layer and the porous layer; and

a filter configured to retain wound exudate in the space between the backing layer and the porous layer;

sealing the wound dressing over the wound; and

applying negative pressure to the wound dressing to draw wound exudate into the space between the backing layer and the porous layer.

53. The method of claim 52, wherein the resiliently-flexible filler is a foam configured to sequester wound exudate.

54. A wound dressing apparatus, comprising:

a backing layer for positioning over a wound area; and

a miniature pump mounted to the backing layer, wherein the miniature pump is operated by a piezoelectric transducer.

55. The wound dressing apparatus of claim 54, wherein the miniature pump is battery-driven.