ELECTROSURGICAL SYSTEM AND METHOD FOR STERILIZING CHRONIC WOUND TISSUE

• US 20100318083A1
• Filed: 07/28/2010
• Published: 12/16/2010
• Est. Priority Date: 01/06/2006
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Davison, Terry S., Warne, Brian, Kwende, Martin
• Granted Patent: US 9,168,087 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 2018/00452 Skin
• CPC Class Codes: A61B 2018/1213 creating an arc
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2218/007 Aspiration

Abstract

An electrosurgical method for sterilizing chronic wound tissue, comprising: positioning an active electrode in proximity to the chronic wound tissue; delivering an electrically conductive fluid proximate the active electrode; and applying a high frequency voltage between the active electrode and a return electrode in the presence of the electrically conductive liquid sufficient to generate an ionized vapor layer at the active electrode, wherein the ionized vapor layer sterilizes at least a portion of the chronic wound tissue.

Claims

1. An electrosurgical method of treating a chronic wound tissue comprising:

positioning an active electrode in proximity to the chronic wound tissue, wherein the chronic wound tissue comprises a wound bed;

delivering an electrically conductive fluid proximate the active electrode;

applying a high frequency voltage between the active electrode and a return electrode in the presence of the electrically conductive liquid sufficient to generate an ionized vapor layer at the active electrode and induce a discharge of energy from the vapor layer, wherein the ionized vapor layer and the discharge of energy molecularly dissociates at least a portion of the chronic wound tissue; and

applying the energy induced from the vapor layer to a target tissue in the vicinity of the chronic wound tissue to sterilize at least a portion of the wound bed.

2. The method of claim 1, wherein the step of molecularly dissociating comprises debriding the at least a portion of the chronic wound tissue.

3. The method of claim 2, wherein debriding further comprises removing tissue to a controlled depth to prepare a bleeding wound bed.

4. The method of claim 1, wherein at least a portion of the energy induced is in the form of photons having a wavelength in the ultraviolet spectrum.

5. The method of claim 1, wherein at least a portion of the energy induced is in the form of energetic electrons.

6. The method of claim 5, wherein the energy evolved by the energetic electrons is greater than 3 eV.

7. The method of claim 1, wherein the step of sterilization comprises inducing the discharge of energy in the form of photons having a wavelength in the ultraviolet spectrum.

8. The method of claim 1, wherein sterilizing at least a portion of the chronic wound tissue comprises removing pathogens in the wound bed and in the vicinity of the chronic wound tissue.

9. The method of claim 1, wherein sterilizing at least a portion of the chronic wound tissue comprises removing bacteria in the wound bed and in the vicinity of the chronic wound tissue.

10. The method of claim 9, wherein removing bacteria in the wound bed and in the vicinity of the chronic wound tissue further comprises substantially reducing a concentration of bacteria in the wound bed.

11. The method of claim 9, further comprising inhibiting the growth of bacteria in the wound bed and in the vicinity of the wound tissue.

12. The method of claim 1, wherein the ionized vapor layer forms a plasma at the active electrode.

13. An electrosurgical method of treating a chronic wound tissue comprising:

positioning an active electrode in proximity to the chronic wound tissue, the chronic wound tissue comprising a wound bed having a surface layer;

positioning a return electrode in the presence of the chronic wound tissue, the return electrode proximally spaced away from the active electrode;

applying a high frequency voltage between the active electrode and the return electrode, wherein the high frequency voltage is sufficient to vaporize and ionize an electrically conductive fluid such that a vapor layer is formed and a discharge of plasma is induced from the vapor layer; and

applying the plasma to the chronic wound tissue wherein a concentration of pathogens in the wound bed is substantially reduced.

14. The method of claim 13, wherein the plasma is comprised of photons having a wavelength in the ultraviolet spectrum.

15. The method of claim 13, wherein the plasma is comprises of energetic electrons.

16. The method of claim 15, wherein the energy evolved by the energetic electrons is greater than 3 eV.

17. The method of claim 13, wherein the pathogens comprise bacteria.

18. The method of claim 17, further comprising inhibiting the growth of bacteria in the wound bed and in the vicinity of the chronic wound tissue.

19. The method of claim 13, further comprising applying the plasma to sterilize at least a portion of the wound bed.

20. An electrosurgical method of treating a chronic wound tissue comprising:

positioning an active electrode is proximity to the chronic wound tissue, wherein the chronic wound tissue comprises a wound bed;

positioning a return electrode in the presence of the chronic wound tissue, the return electrode proximally spaced from the active electrode;

applying a high frequency voltage between the active electrode and the return electrode, the high frequency voltage sufficient to develop high electric field intensities associated with an ionized vapor layer proximate the active electrode, wherein the ionized vapor layer engages the chronic wound tissue sufficient to molecularly dissociate at least a portion of the chronic wound tissue;

wherein the molecular dissociation of the at least a portion of the chronic wound tissue expresses hydroxyl radicals in the vicinity of the wound bed; and

whereby the hydroxyl radicals enhance sterilization of at least a portion of the wound bed.

21. The method of claim 20, wherein expressing hydroxyl radicals further comprises increasing a level of interleukin (IL)-8 expression.

22. The method of claim 21, wherein increasing the level of interleukin (IL)-8 expression results in a higher rate of neutrophil attraction to the chronic wound tissue, whereby the neutrophil attraction produces reactive oxygen species (ROS) for substantially reducing a concentration of bacteria in the wound bed.

23. The method of claim 20, wherein molecularly dissociating the at least a portion of the chronic wound tissue further comprises debriding the tissue to a controlled depth to form a bleeding wound bed.