Combined electrosurgery/cautery system and method

• US 4,196,734 A
• Filed: 02/16/1978
• Issued: 04/08/1980
• Est. Priority Date: 02/16/1978
• Status: Expired due to Term

• Current Assignee: Valleylab Inc. (Medtronic Plc)
• Original Assignee: Valleylab Inc. (Medtronic Plc)
• Inventors: Harris, Frank W.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US05/878,529
• Time in Patent Office: 782 Days
• Field of Search: 128/303.1, 128/303.13-303.19, 219/233-235, 219/240, 219/241
• US Class Current: 606/31
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1233 with circuits for assuring patient safety
• CPC Class Codes: A61B 2018/1273 including multiple generators in one device

Abstract

A combined electrosurgery/cautery system wherein a common heater/electrode element is employed to effect electrosurgical and cautery procedures.

Claims

1. A combined electrosurgery and cautery system for use with a patient, said system comprising

a combined heater and electrode element;

cautery power supply means for applying a first electrical current through said combined heater and electrode element to heat said element, said cautery power supply means including means for passing said first current through said element back to the cautery power supply means without passing through said patient so that tissue of said patient is necrosed by said first current in response to the element being positioned adjacent the tissue;

electrosurgical generator means for applying a second electrical current to said combined heater and electrode element, said electrosurgical generator means including means for passing said second current through said patient back to the electrosurgical generator means where said electrosurgical generator means produces a voltage on said element, the magnitude of which is sufficiently high to permit arcing from the element to the patient after said tissue has been necrosed by said first current.

2. A system as in claim 1 including current limiting means for limiting said second electrical current through said patient to an arcing only value at which desiccation of the patient'"'"'s tissue is not likely.

3. A system as in claim 2 where said arcing only value is not more than about 200 ma.

4. A system as in claim 2 where said electrosurgical generator means includes power adjusting means for adjusting the output power delivered to said combined heater and electrode element and where said current limiting means includes feedback means for providing a feedback signal from said element, said power adjusting means being responsive to said feedback signal to thereby limit said second current to said arcing only value.

5. A system as in claim 2 including a first isolation transformer, the primary winding of which is connected to said electrosurgical generator meanns and the secondary winding of which is connected to said combined heater and electrode element and where the output impedance of said transformer is sufficiently high to limit said second current to said arcing only value.

6. A system as in claim 1 including a handpiece adapted for manual manipulation, said combined heater and electrode element being mounted on said handpiece and a current step-up transformer disposed within said handpiece, the secondary winding of said transformer being connected across said element and first and second wires connected from said cautery power supply means to the respective ends of the primary winding of said transformer whereby said wires may be of a fine gauge due to the current step-up effected by the transformer.

7. A system as in claim 6 where said cautery power supply means is an alternating current source, the frequency of which is high enough to avoid neuromuscular stimulation.

8. A system as in claim 7 where the frequency of said alternating current is about 120 KHz.

9. A system as in claim 8 including an isolating transformer, the primary winding of which is connected to said cautery power supply means and the secondary of which is respectively connected to said first and second wires.

10. A system as in claim 6 where said electrosurgical generator means is connected to one of said first and second wires.

11. A system as in claim 1 including means for isolating said cautery power supply means from ground.

12. A system as in claim 1 where said cautery power supply means is an alternating current source.

13. A system as in claim 1 wherre said combined heater and electrode element comprises a resistance wire wound about an electrically insulative core.

14. A system as in claim 13 where said core comprises glass fibers.

15. A system as in claim 1 where said combined heater and electrode element comprises a substrate of electrically insulating material, an electrically conductive wire deposited thereon, said wire being connected to said cautery power supply means and said electrosurgical generator means and a high resistivity, conductive covering disposed over said electrically conductive wire.

16. A system as in claim 15 where said substrate comprises a ceramic material, said wire comprises a nickel alloy and said cover comprises a carbon film.

17. A system as in claim 1 where said combined heater and electrode element has a loop configuration.

18. A system as in claim 17 including means for moving the loop in a predetermined direction whereby the loop may be encircled about a growth or the like on the patient to thereby effect electrosurgical removal of the growth.

19. A system as in claim 17 where said loop configuration is an elongated hairpin configuration.

20. A system as in claim 1 including means for regulating the amount of said first current passing through said combined heater and electrode element to thereby maintain the temperature of said element at a predetermined value.

21. A system as in claim 20 including means for establishing the predetermined value of the temperature of said combined heater and electrode element.

22. A system as in claim 21 where said temperature establishing means includes means for setting the temperature of said element to a value which will cause desiccation of the patient'"'"'s tissue.

23. A system as in claim 22 where said temperature establishing means includes means for setting the temperature of said element to a value which will cause cutting of the patient'"'"'s tissue.

24. A system as in claim 1 where said cautery power supply means is a direct current source.

25. A system as in claim 24 including a handpiece upon which is disposed said combined heater and electrode element and where said direct current source comprises a battery disposed within said handpiece.

26. A system as in claim 25 including means for recharging said battery.

27. A system as in claim 1 including a return electrode adapted for contact with said patient, said return electrode being connected to said electrosurgical generator means to thereby provide a return path for said second current to said electrosurgical generator means.

28. A system as in claim 27 where the surface area of said return electrode adapted for contact with said patient is no more than 60 square centimeters.

29. A system as in claim 28 where said surface area is no more than 10 square centimeters.

30. A system as in claim 27 including switching means having a first position in which said return electrode is connected to said electrosurgical generator means and a second position in which said electrosurgical generator means is disconnected from said return electrode and connected to ground so that, when no return electrode is employed, a return path for said second current is provided through said patient to said ground and then from said ground back to the electrosurgical generator means.

31. A system as in claim 1 including means for providing the intended return path for said second current through said patient to ground and then from said ground back to the electrosurgical generator means whereby a large area return electrode does not have to be applied to said patient to provide a return path for said second current.

32. A system as in claim 1 where said combined heater and electrode element comprises a cautery heater and an electrosurgical electrode.

33. A system as in claim 32 where cautery heater and said electrosurgical electrode are one and the same element.

34. An electrosurgical method comprising

placing a combined heater and electrode element adjacent tissue to a patient to be treated;

passing a first current through said combined heater and electrode element to effect necrosis of said tissue where said first current is passed through said element without passing through said tissue; and

passing a second current through said combined heater and electrode element and through said patient so that an arc is established between said element and said patient after the tissue is necrosed by said first current.

35. A method as in claim 34 where the magnitude of said second current is less than that which is needed to initiate said arc.

36. A method as in claim 35 where said magnitude of the second current is not more than about 200 ma.

37. A method as in claim 34 where said second current comprises a sine wave suitable for cutting said tissue.

38. A method as in claim 34 where said second current comprises bursts of high frequency electrical energy suitable for fulguration of said tissue.

39. A method as in claim 34 where said second current passes directly from said patient without passing through a return electrode.