Patent EA-002484-B1 (EA)
Title: Electrosurgical system for reducing/removing eschar accumulations on lectrosurgical instruments
Inventor: HEIM WARREN PAUL
IPC: A61B18/12
Filed: 1998-10-05
Abstract: 1. An electrosurgical method for providing an electrically-closed circuit and supplying an electrosurgical signal to a working surface of an electrosurgical instrument for conveying electrical energy to the tissue site from said working surface, characterized in that said electrosurgical signal is used having a negative average voltage bias. 2. An electrosurgical method as recited in claim 1, said supplying step including combining a first signal component and a second signal component to obtain said electrosurgical signal. 3. An electrosurgical method as recited in claim 2, said supplying step further including utilizing a radio frequency electrosurgical generator to generate said first signal component. 4. An electrosurgical method as recited in claim 3, said supplying step further including employing said first signal component to obtain said second signal component. 5. An electrosurgical method as recited in claim 4, wherein said first signal component has a first frequency and said second signal component has a second frequency, said second frequency being less than said first frequency. 6. An electrosurgical method as recited in claim 5, wherein said first frequency is more than about 100 kHz and said second frequency is less than about 10 kHz. 7. An electrosurgical method as recited in claim 3, said supplying step further including employing an electrical energy source, separate from said radio frequency electrosurgical generator, to provide said second signal component. 8. An electrosurgical method as recited in claim 5, further comprising utilizing at least one first frequency-biased blocking component to isolate said electrosurgical generator from said electrical energy source; employing at least one second-frequency biased blocking component to isolate said electrical energy source from said electrosurgical generator. 9. An electrosurgical method as recited in claim 7, wherein said electrical energy source is selected from the group comprising a DC energy source, and a time-varying energy source having an operating frequency less than an operating frequency of the radio frequency electrosurgical generator. 10. A clectrosurgical method as recited in claim 4, wherein said second signal component is a DC signal. 11. An electrosurgical method as recited in claim 2, further comprising cleaning said working surface of said electrosurgical instrument, wherein said cleaning step includes applying an electrical cleaning signal, different from said electrosurgical signal, to said working surface. 12. An electrosurgical method as recited in claim 11, further comprising contacting said electrosurgical instrument with a conductive liquid; contacting a conductive return electrode with said conductive liquid, wherein a negative voltage bias is provided at said electrosurgical instrument relative to said return electrode. 13. The method as recited in claim 1, wherein the average bias voltage exceeds about 1 volt. 14. The method as recited in claim 13, wherein the average bias voltage is between about 1 and 60 volts. 15. The method as recited in claim 1, wherein the working surface comprises stainless steel. 16. The method as recited in claim 1, wherein the working surface comprises at least one material having a standard reduction potential that is positive with respect to a standard hydrogen electrode. 17. The method as recited in claim 16, wherein the working surface comprises at least one material selected from a group comprising the elements of Group IB of the Periodic Chart of Elements. 18. The method as recited in claim 17, wherein the working surface comprises at least one of the group comprising, copper, silver and gold. 19. The method as recited in claim 1, further comprising spraying the working surfaces with a conductive liquid during at least said conveying step. 20. An electrical system comprising an electrical circuit having an electrode for supplying an electrosurgical signal to an electrosurgical instrument and a return electrode, characterized in that comprises means for providing a negative-biasing signal component and means for combining said negative-biasing signal component with a radio frequency signal component to provide an electrosurgical signal. 21. The electrical system as recited in claim 20 further comprising an electrosurgical generator for providing said radio frequency signal component. 22. The electrical system as recited in claim 21, said means for providing including an electrical energy source separate from said electrosurgical generator. 23. The electrical system as recited in claim 22, wherein said electrical energy source comprises at least one of a direct current energy source and a time-varying energy source. 24. The electrical system as recited in claim 22, wherein said time-varying energy source and said electrosurgical generator are isolated by blocking components. 25. The electrical system as recited in claim 21, wherein said means for providing utilizes said radio-frequency signal component to generate said negative biasing signal component. 26. An electrical system as recited in claim 20, further comprising a hand-held electrosurgical instrument defining said supply path and having working surfaces comprising stainless steel. 27. An electrical system as recited in claim 20, further comprising a hand-held electrosurgical instrument defining said supply path and having working surfaces comprising at least one material from the group comprising: copper, silver and gold. 28. An electrical system as recited in claim 20, further comprising a hand-held electrosurgical instrument defining said supply path; and means for applying an electrical signal, separate from said electrosurgical signal, to said electrosurgical instrument during a cleaning procedure. 29. An electrical system as recited in claim 28, further comprising a cleaning assembly for receiving said electrosurgical instrument during said cleaning procedure, comprising a conductive liquid; and a return electrode in electrical contact with said liquid.