Wound treatment employing reduced pressure

• US 5,636,643 A
• Filed: 03/09/1993
• Issued: 06/10/1997
• Est. Priority Date: 11/14/1991
• Status: Expired due to Term

• Current Assignee: Wake Forest University Health Sciences
• Original Assignee: Wake Forest University
• Inventors: Morykwas, Michael J., Argenta, Louis C.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Lacyk, John P.
• Application Number:
  US08/028,677
• Time in Patent Office: 1,554 Days
• Field of Search: 128/897-898, 602/42-53
• US Class Current: 128/897
• CPC Class Codes: A61B 17/08 Wound clamps or clips, i.e. not or only partly penetrating the tissue suture bridges A61B17/0466; Devices for bringing together the edges of a wound
• CPC Class Codes: A61B 17/085 with adhesive layer
• CPC Class Codes: A61B 2017/00557 inflatable A61B2017/22051 takes precedence
• CPC Class Codes: A61B 2017/306 holding by means of suction
• CPC Class Codes: A61B 2090/401 using air flow
• CPC Class Codes: A61B 90/00 Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges protective face masks A41D13/11; surgeon's or patient's gowns or dresses A41D13/12; devices for carrying-off, for treatment of, or for carrying-over, body liquids A61M1/00
• 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 2013/00174 possibility of applying pressure
• CPC Class Codes: A61F 2013/00519 for treating burn bandages for burns or skin transplants A61F2013/00157
• CPC Class Codes: A61F 2013/0054 for deep wounds
• CPC Class Codes: A61F 2013/00919 for physical therapy, e.g. cold or magnetic
• CPC Class Codes: A61M 1/08 Cupping glasses , i.e. for enhancing blood circulation
• CPC Class Codes: A61M 1/75 Intermittent or pulsating suction A61M1/63, A61M1/772 take precedence
• CPC Class Codes: A61M 1/782 using valves with freely moving parts, e.g. float valves
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/79 Filters for solid matter specially adapted for dental use A61C17/065
• CPC Class Codes: A61M 1/84 Drainage tubes; Aspiration tips for negative pressure wound therapy A61M1/90; for surgical cutting instruments A61B17/32
• CPC Class Codes: A61M 1/96 Suction control thereof
• CPC Class Codes: A61M 1/982 with means for detecting level of collected exudate
• CPC Class Codes: A61M 2205/3379 : Masses, volumes, levels of fluids in reservoirs, flow rates
• 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 method of treating tissue damage comprises applying a negative pressure to a wound sufficient in time and magnitude to promote tissue migration and thus facilitate closure of the wound. The method is applicable to wounds, burns, infected wounds, and live tissue attachments. A wound treatment apparatus is provided in which a fluid impermeable wound cover is sealed over a wound site. A screen in the form of an open-cell foam screen or a rigid porous screen is placed beneath the wound cover over the wound. A vacuum pump supplies suction within the wound cover over the treatment site.

Claims

1. An appliance for administering a reduced pressure treatment to a would comprising:

(a) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound;

(b) a seal adapted to seal said cover to tissue surrounding the wound;

(c) reduced pressure supply means for connection to a source of suction, said reduced pressure supply means cooperating with said cover to supply said reduced pressure beneath said cover; and

(d) a screen adapted to prevent overgrowth of wound tissue, said screen being located between said wound and said cover.

2. The appliance as recited in claim 1 wherein said screen comprises a porous sheet.

3. The appliance as recited in claim 1 wherein said seal includes an adhesive material on the cover adapted to secure said cover to the tissue surrounding the wound.

4. The appliance as recited in claim 1 wherein said screen comprises a foam screen.

5. An appliance for administering a reduced pressure treatment to a wound comprising:

(a) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound;

(b) a seal adapted to seal said cover to tissue surrounding the wound; and

(c) reduced pressure supply means for connection to a source of suction, said reduced pressure supply means cooperating with said cover to supply said reduced pressure beneath said cover, wherein said reduced pressure supply means comprises a screen having an open cell foam and said reduced pressure supply means includes a segment of tubing embedded within said screen.

6. An apparatus for treating a wound comprising:

(a) a vacuum system adapted to produce a reduced pressure, wherein said vacuum system includes a collection device for collecting fluid aspirated from the wound, wherein said collection device includes means for halting said application of reduced pressure to the wound when said fluid exceeds a predetermined quantity; and

(b) a reduced pressure appliance operably connected with said vacuum system adapted to apply said reduced pressure to the wound, the appliance including;

(i) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound;

(ii) a seal adapted to seal said cover to tissue surrounding the wound; and

(iii) reduced pressure supply means for connection with the vacuum system adapted to supply said reduced pressure within said cover to the wound.

7. The apparatus as recited in claim 6 wherein said reduced pressure is from about 2 in. Hg below atmospheric pressure to about 7 in. Hg below atmospheric pressure.

8. The apparatus of claim 6 wherein said reduced pressure supply means comprises a length of tubing, said collection device comprises an aspirating container connected along said length of tubing between said vacuum system and cover, and said halting means comprises a flotation valve within said aspirating container for blocking said tubing when a predetermined amount of fluid is collected within said container.

9. The apparatus of claim 6 wherein said collection device comprises an expandable chamber and said means for halting said application of reduced pressure comprises sensing means for sensing expansion of said expandable chamber, said sensing means operatively connected with said vacuum system so that said reduced pressure is halted when a predetermined expansion of said expandable chamber is sensed by said sensing means.

10. The apparatus of claim 6 wherein said reduced pressure supply means comprises a length of tubing and said halting means comprises a filter along said tubing, said filter having pores that block the supply of reduced pressure via said tubing when said pores are filled with said fluid.

11. A method treating a wound comprising the steps of:

(a) applying a reduced pressure to the wound, wherein said applying step comprises the steps of;

(i) placing a porous screen over the wound;

(ii) locating an impermeable cover over the wound, said cover having a suction port;

(iii) sealing the periphery of said impermeable cover to tissue surrounding the wound; and

(iv) operably connecting said suction port with a vacuum system for producing said reduced pressure; and

(b) maintaining said reduced pressure until the wound has progressed toward a selected stage of healing.

12. The method as recited in claim 11 wherein said reduced pressure is from about 2 in. Hg below atmospheric pressure to about 7 in. Hg below atmospheric pressure.

13. A method of treating a wound comprising the steps of:

(a) securing an appliance for applying reduced pressure to the wound; and

(b) providing reduced pressure to said appliance in alternating intervals of application and non-application.

14. The method as recited in claim 13 wherein said reduced pressure is from about 2 in. Hg below atmospheric pressure to about 7 in. Hg below atmospheric pressure.

15. A method of pretreating a skin flap to promote attachment of the flap to a wound comprising the step of applying reduced pressure to a region of skin tissue adjacent to the wound prior to detachment of said skin tissue adjacent to the wound to form the flap from said region of skin.

16. An appliance for administering a reduced pressure treatment to a wound comprising:

(a) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound, wherein said cover comprises a flexible sheet;

(b) a seal adapted to seal said cover to tissue surrounding the wound; and

(c) reduced pressure supply means for connection to a source of suction, said reduced pressure supply means cooperating with said cover to supply said reduced pressure beneath said cover.

17. The appliance of claim 16 comprising support means for supporting said sheet outward from the wound.

18. The appliance of claim 17 wherein said support means comprises a support member located between said sheet and the wound.

19. The appliance of claim 18 wherein said support member includes a porous cup member having attachment means for connecting with said reduced pressure supply means.

20. The appliance of claim 18 further comprising a pad between the wound and said support member for alleviating discomfort caused in the wound by said support member.

21. The appliance of claim 17 wherein said support means comprises a support member extending outwardly over the wound and external to said sheet.

22. The appliance of claim 21 wherein said support means comprises attachment means for attaching said sheet to said support means, said attachment means having a connecting member for connecting with said reduced pressure supply means for providing said reduced pressure beneath said sheet, and said support member comprising a plurality of leg members attached to said attachment means for holding said attachment means and said sheet outward from the wound.

23. An appliance for administering a reduced pressure treatment to a wound comprising:

(a) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound, wherein said cover is sufficiently rigid to support said cover out of contact with the wound;

(b) a seal adapted to seal said cover to tissue surrounding the wound;

(c) reduced pressure supply means for connection to a source of suction, said reduced pressure supply means cooperating with said cover to supply said reduced pressure beneath said cover, wherein said reduced pressure supply means comprises a suction port on said cover; and

(d) a screen adapted to prevent overgrowth of the wound for placement at a location between the wound and said cover and secured in said location by the periphery of said cover.

24. The appliance of claim 23 wherein said screen comprises a sheet-like mesh.

25. The appliance of claim 23 wherein said seal includes an adhesive material on the cover adapted to adhere to tissue surrounding the wound and a seal member at least partially overlying said cover.

26. An apparatus for treating a wound comprising:

(a) a vacuum system adapted to produce a reduced pressure, wherein said vacuum system comprises;

(i) a vacuum pump; and

(ii) a filter for preventing said pump from venting micro-organisms aspirated from the wound; and

(b) a reduced pressure appliance operably connected with said vacuum system adapted to apply said reduced pressure to the wound, the appliance including;

(i) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound;

(ii) a seal adapted to seal said cover to tissue surrounding the wound; and

(iii) reduced pressure supply means for connection with the vacuum system adapted to supply said reduced pressure to the wound, wherein said reduced pressure supply means comprises a length of tubing connected between said vacuum system and said cover.

27. The apparatus of claim 26 wherein said filter is connected along said tubing between said pump and said cover for preventing contamination of said pump.

28. An apparatus for treating a wound comprising:

(a) a vacuum system adapted to produce a reduced pressure, wherein said vacuum system comprises control means for cyclically controlling said production of reduced pressure in alternating periods of production and non-production of reduced pressure; and

(b) a reduced pressure appliance operably connected with said vacuum system adapted to apply said reduced pressure to the wound, the appliance including;

(i) an impermeable cover adapted to cover and enclose the wound and adapted to maintain reduced pressure at the site of the wound;

(ii) a seal adapted to seal said cover to tissue surrounding the wound; and

(iii) reduced pressure supply means for connection with the vacuum system adapted to supply said reduced pressure to the wound.

29. A method of treating a wound comprising the steps of:

(a) applying a reduced pressure to the wound; and

(b) maintaining said reduced pressure until the wound has progressed toward a selected stage of healing, wherein said maintaining of said reduced pressure is conducted in alternating periods of application and non-application of the reduced pressure.

30. The method of claim 29 wherein each of said alternating periods is about 5 minutes.

31. A method of treating a wound comprising the steps of:

(a) applying a reduced pressure to the wound; and

(b) maintaining said reduced pressure until the wound has progressed toward a selected stage of healing, wherein said selected stage of healing is cessation of partial thickness burn progression.

32. A method of treating a wound comprising the steps of:

(a) applying a reduced pressure to the wound; and

(b) maintaining said reduced pressure until the wound has progressed toward a selected stage of healing, wherein said selected stage of healing is a reduction in bacterial density in the wound by at least 50%.

33. A device for promoting closure of a wound comprising:

(a) an impermeable deformable cover adapted to be placed over the wound;

(b) an adhesive layer on the cover adapted to form a seal between said cover and tissue surrounding the wound;

(c) support means for supporting said cover outward from the wound forming an enclosed volume bounded by said cover and the wound and tissue surrounding the wound; and

(d) supply means for supplying reduced pressure to said enclosed volume and for deforming said cover so as to exert tension upon the tissue surrounding the wound.

34. The device of claim 33 wherein said support means comprises a support member located within said enclosed volume.

35. The device of claim 34 wherein said support member comprises a porous cup member.

36. The device of claim 33 wherein said support means comprises a support member located external to said enclosed volume.

37. The appliance of claim 36 wherein said support means comprises attachment means for attaching said cover to said support means, and said support means comprises a plurality of leg members for supporting said cover out of contact with the wound.

38. A method of promoting attachment of a skin graft onto a wound comprising steps of:

(a) attaching the graft to the wound, and

(b) applying reduced pressure to the graft to promote blood circulation within the graft.

39. The method of claim 38 wherein the graft is a skin flap, the method further comprising steps of:

(a) applying reduced pressure to a region of skin adjacent to the wound, and

(b) forming the flap by detaching skin from said region prior to said attaching step.

40. The method of claim 38 comprising steps of:

(a) applying reduced pressure to a region of skin for use as the skin graft; and

(b) forming the graft by detaching skin from said region.