Apparatus and method for wound treatment employing periodic sub-atmospheric pressure

• US 9,737,455 B2
• Filed: 11/18/2013
• Issued: 08/22/2017
• Est. Priority Date: 01/10/2007
• Status: Active Grant

• Current Assignee: Wake Forest University Health Sciences
• Original Assignee: Wake Forest University Health Sciences
• Inventors: Argenta, Louis C, Morykwas, Michael J, Webb, Lawrence X
• Primary Examiner(s): Zalukaeva, Tatyana
• Assistant Examiner(s): TREYGER, ILYA Y
• Application Number:
  US14/082,951
• Publication Number:
  US 20140155790A1
• Time in Patent Office: 1,373 Days
• Field of Search: 604305, 604306, 604307, 604308, 604313, 604315, 604316
• CPC Class Codes: A61H 7/001 without substantial movement between the skin and the device
• CPC Class Codes: A61M 1/75 Intermittent or pulsating suction A61M1/63, A61M1/772 take precedence
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/96 Suction control thereof

Abstract

A tissue treatment apparatus and method are provided for treating tissue by the application of the time-varying sub-atmospheric pressure. The apparatus includes a cover adapted to cover a wound and adapted to maintain sub-atmospheric pressure the site of the wound. The apparatus further includes a source of suction configured to generate a time-varying sub-atmospheric pressure having a periodic waveform comprising a gradual change in pressure. The suction source cooperates with the cover to supply the time-varying sub-atmospheric pressure under the cover to the wound. The time-varying sub-atmospheric pressure may vary between a first pressure value below the inherent tissue tension of the wound tissue and a second pressure value above the inherent tissue tension of the wound tissue.

Claims

1. A method for growing wound tissue employing gradually varying sub-atmospheric pressure, the method comprising:

(a) overlaying wound tissue with a reticulated screen configured to stimulate tissue growth at the wound tissue;

(b) enclosing the reticulated screen and the wound tissue under a cover to provide an enclosure above the wound tissue and the reticulated screen in which sub-atmospheric pressure may be maintained; and

(c) applying a non-intermittent, gradually varying sub-atmospheric pressure to the enclosure from a source of sub-atmospheric pressure operably connected to the cover, and maintaining the non-intermittent, gradually varying sub-atmospheric pressure for a time sufficient to stimulate tissue growth at the wound tissue.

2. The method of claim 1, wherein the step of applying a non-intermittent, gradually varying sub-atmospheric pressure comprises applying a sinusoidal waveform variation in sub-atmospheric pressure.

3. The method of claim 1, wherein the step of applying a non-intermittent, gradually varying sub-atmospheric pressure comprises applying a triangular waveform variation in sub-atmospheric pressure.

4. The method of claim 1, wherein the step of applying a non-intermittent, gradually varying sub-atmospheric pressure comprises applying a saw-tooth waveform variation in sub-atmospheric pressure.

5. The method according to any one of claims 1-4, wherein the step of applying a non-intermittent, gradually varying sub-atmospheric pressure comprises applying a pressure value of between about 25 mmHg below atmospheric pressure and 100mmHg below atmospheric pressure.

6. The method according to any one of claims 1-4, wherein the cover comprises a flexible self-adhesive sheet.

7. The method according to any one of claims 1-4, wherein the reticulated screen comprises an open-cell foam, a synthetic polymer material, a non-adherent material, a polymer mesh, or a combination thereof.

8. The method according to any one of claims 1-4, wherein the step of applying a sub-atmospheric pressure comprises communicating the sub-atmospheric pressure through a port that is operably connected to both the source of sub-atmospheric pressure and the cover.

9. The method according to claim 8, wherein the step of applying a sub-atmospheric pressure comprises communicating the sub-atmospheric pressure through a tube that is operably connected to the port and the source of sub-atmospheric pressure.

10. The method according to any one of claims 1-4, wherein step of applying a non-intermittent, gradually varying sub-atmospheric pressure comprises applying a digitized waveform.

21. The method according to any one of claims 1-4, wherein the screen has a degree of reticulation is selected to deter tissue growth within the reticulated screen.

22. The method according to any one of claims 1-4, wherein the screen comprises a bioabsorbable material.

11. An apparatus employing gradually varying sub-atmospheric pressure for growing wound tissue, the apparatus comprising:

(a) a reticulated screen configured to stimulate tissue growth at the wound tissue;

(b) a cover configured to enclose the wound tissue and the reticulated screen and provide an enclosure above the wound tissue and the reticulated screen in which sub-atmospheric pressure may be maintained; and

(c) a source of sub-atmospheric pressure configured to apply and maintain a non-intermittent, gradually varying sub-atmospheric pressure to the enclosure for a time sufficient to stimulate tissue growth at the wound tissue.

12. The apparatus of claim 11, wherein the source of sub-atmospheric pressure is configured to apply and maintain a sinusoidal waveform variation in sub-atmospheric pressure.

13. The apparatus of claim 11, wherein the source of sub-atmospheric pressure is configured to apply and maintain a triangular waveform variation in sub-atmospheric pressure.

14. The apparatus of claim 11, wherein the source of sub-atmospheric pressure is configured to apply and maintain a saw-tooth waveform variation in sub-atmospheric pressure.

15. The apparatus of claim 11, wherein the source of sub-atmospheric pressure is configured to provide a sub-atmospheric pressure having a pressure value of between about 25 mmHg below atmospheric pressure and 100 mmHg below atmospheric pressure.

16. The apparatus of claim 11, wherein the cover comprises a flexible self-adhesive sheet.

17. The apparatus of claim 11, wherein the reticulated screen comprises an open-cell foam, a synthetic polymer material, a non-adherent material, a polymer mesh, or a combination thereof.

18. The apparatus of claim 11, comprising a port operably connected to the cover.

19. The apparatus of claim 18, comprising a tube operably connected to the source of sub-atmospheric pressure and the port.

20. The apparatus of claim 11, wherein the source of sub-atmospheric pressure is configured to apply and maintain a digitized waveform variation in sub-atmospheric pressure.

23. The apparatus of any one of claims 11-14, wherein the screen has a degree of reticulation selected to deter tissue growth within the reticulated screen.

24. The apparatus of any one of claims 11-14, wherein the screen comprises a bioabsorbable material.