Fluid-assisted electrosurgical device

• US 7,364,579 B2
• Filed: 01/23/2007
• Issued: 04/29/2008
• Est. Priority Date: 02/22/1995
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Hoey, Michael F., Mulier, Peter M. J.
• Primary Examiner(s): Cohen; Lee S.
• Application Number:
  US11/656,607
• Publication Number:
  US 20070118114A1
• Time in Patent Office: 462 Days
• Field of Search: 606/41, 606/45, 606/46, 606/49, 607/99
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61B 2018/00196 reciprocating lengthwise
• CPC Class Codes: A61B 2018/00291 using suction
• CPC Class Codes: A61B 2018/1253 monopolar
• CPC Class Codes: A61B 2018/1417 Ball
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2018/1475 Electrodes retractable in or deployable from a housing
• CPC Class Codes: A61B 2018/1861 with an instrument inserted into a body lumen or cavity, e.g. a catheter
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 2218/007 Aspiration

Abstract

An electrocautery device is disclosed. In accordance with one aspect of the invention, the electrocautery electrode/tip is provided with a hollow, conductive tube terminating at its distal end in a ball point type tip. Fluid, preferably conductive fluid, is applied to the proximal end of the hollow electode/tip, and expelled from the distal end thereof during electrocautery. The ball point distal tip allows the distal tip to be directly applied to the tissue and “rolled” or slid along the tissue. This allows the distal tip to be moved across the tissue without dragging or snagging on the tissue. In addition, the conductive fluid expelled from the distal tip further lubricates the distal tip as it moves across the tissue. If conductive fluid is used, the conductive fluid emanating from the electrode/tip conducts the RF electrocautery energy away from the distal tip so that it is primarily the fluid, rather than the distal tip that actually accomplishes the cauterizing of tissue. That is, the fluid serves as a “virtual” electrocautery electrode. Since it is the fluid, rather than the distal tip that cauterizes, coagulates and ablates, no burns or perforations are made to the tissue, reducing the amount of debris at the site. Also, the flow of fluid through the electrode/tip tends to keep the distal tip clean and cool.

Claims

1. A fluid-assisted electrosurgical instrument, comprising:

a handle maintaining a tube having a proximal and a distal end, at least a portion of the distal end of the tube being electrically conductive, the tube defining a lumen extending proximally from the distal end of the tube, the lumen being connectable to a source of fluid under pressure, the electrically conductive portion of the tube being connectable to a source of radio-frequency energy; and

an electrically conductive contact element, wherein a first portion of the contact element is enclosed within the tube at the distal end of the tube and a second portion of the contact element extends distally beyond the distal end of the tube.

2. The electrosurgical instrument according to claim 1, wherein the contact element is freely rotatable within the tube.

3. The electrosurgical instrument according to claim 1, wherein a portion of the tube is crimped around the contact element.

4. The electrosurgical instrument according to claim 1, further including a fluid source in communication with the lumen.

5. The electrosurgical instrument according to claim 4, wherein the fluid source comprises an input line and a pump.

6. The electrosurgical instrument according to claim 4, wherein the fluid source comprises a canister.

7. The electrosurgical instrument according to claim 6, wherein the canister is pre-pressurized.

8. The electrosurgical instrument according to claim 7, wherein the canister is received within the handle.

9. The electrosurgical instrument according to claim 1, wherein the contact element is porous.

10. The electrosurgical instrument according to claim 1, further including a suction tube disposed within the tube.

11. The electrosurgical instrument according to claim 1, wherein the tube is fabricated from an electrically insulating material except for a portion at the distal end that contacts the contact element.

12. The electrosurgical instrument of claim 1, wherein the contact element is made of metal.

13. The electrosurgical instrument of claim 1, wherein the tube is made of metal.

14. The electrosurgical instrument of claim 1, wherein the handle is made of a sterilizable material.

15. The electrosurgical instrument of claim 1, further comprising wiring electrically connected to the electrically conductive portion of the tube for connecting a source of radiofrequency energy to the tube.

16. The electrosurgical instrument according to claim 1, further including a source of radiofrequency energy electrically connected to the electrically conductive portion of the tube.

17. The electrosurgical instrument of claim 16, wherein the source of radiofrequency energy includes a radiofrequency generator, and further wherein a positive terminal of the radiofrequency generator is electrically coupled to the tube.

18. The electrosurgical instrument of claim 1, further comprising a source of fluid under pressure connected to the lumen, wherein the fluid is selected from the group consisting of saline, saturated saline and Ringer'"'"'s solution.

19. The electrosurgical instrument of claim 1, further comprising a source of fluid under pressure connected to the lumen, wherein the fluid includes a dye.

20. The electrosurgical instrument of claim 19, wherein the dye is methylene blue.

21. The electrosurgical instrument of claim 1, wherein the contact element is spherical.

22. The electrosurgical instrument of claim 1, wherein the contact element is non-spherical.

23. The electrosurgical instrument of claim 1, wherein the contact element is a plug.

24. The electrosurgical instrument of claim 1, wherein the contact element is adapted to expel fluid applied to the lumen through the second portion.

25. The electrosurgical instrument of claim 1, wherein the second portion of the contact element is rounded.

26. An electrosurgical instrument comprising:

a handle;

a tube mounted to the handle and having a proximal and a distal end, at least a portion of the distal end of the tube being electrically conductive and connectable to a source of radiofrequency energy;

a fluid passage for delivering a fluid to the distal end of the tube; and

an electrically conductive contact element at least a portion of which is enclosed within the tube at the distal end of the tube.

27. The electrosurgical instrument according to claim 26, wherein the contact element is freely rotatable within the tube.

28. The electrosurgical instrument according to claim 26, wherein a portion of the tube is crimped around the contact element.

29. The electrosurgical instrument according to claim 26, further including a fluid source in communication with the fluid passage.

30. The electrosurgical instrument according to claim 29, wherein the fluid source comprises an input line and a pump.

31. The electrosurgical instrument according to claim 29, wherein the fluid source comprises a canister.

32. The electrosurgical instrument according to claim 31, wherein the canister is pre-pressurized.

33. The electrosurgical instrument according to claim 31, wherein the canister is received within the handle.

34. The electrosurgical instrument according to claim 26, wherein the contact element is porous.

35. The electrosurgical instrument according to claim 26, further including a suction tube disposed within the tube.

36. The electrosurgical instrument according to claim 26, wherein the tube is fabricated from an electrically insulating material except for a portion at the distal end that contacts the contact element.

37. The electrosurgical instrument of claim 26, wherein the contact element is made of metal.

38. The electrosurgical instrument of claim 26, wherein the tube is made of metal.

39. The electrosurgical instrument of claim 26, wherein the handle is made of sterilizable material.

40. The electrosurgical instrument of claim 26, further comprising wiring electrically connected to the electrically conductive portion of the tube for connecting the source of radiofrequency energy to the tube.

41. The electrosurgical instrument according to claim 26, further including a source of radiofrequency energy electrically connected to the electrically conductive portion of the tube.

42. The electrosurgical instrument of claim 41, wherein the source of radiofrequency energy includes a radiofrequency generator, and further wherein a positive terminal of the radiofrequency generator is electrically coupled to the tube.

43. The electrosurgical instrument of claim 26, further comprising a source of fluid under pressure connected to the fluid passage, wherein the fluid is selected from the group consisting of saline, saturated saline and Ringer'"'"'s solution.

44. The electrosurgical instrument of claim 26, further comprising a source of fluid under pressure connected to the fluid passage, wherein the fluid includes a dye.

45. The electrosurgical instrument of claim 44, wherein the dye is methylene blue.

46. The electrosurgical instrument of claim 26, wherein the contact element is spherical.

47. The electrosurgical instrument of claim 26, wherein the contact element is non-spherical.

48. The electrosurgical instrument of claim 26, wherein the contact element is a plug.

49. The electrosurgical instrument of claim 26, wherein the contact element defines a first portion maintained within the tube and a second portion extending distal the tube, the contact element adapted to expel fluid applied to the fluid passage through the second portion.

50. The electrosurgical instrument of claim 49, wherein the second portion is rounded.

51. An electrosurgical instrument for ablating through a chest of a patient a length of tissue for treating atrial fibrillation, the electrosurgical instrument comprising:

a rigid, elongated electrode having a proximal end, a distal end, and an internal lumen extending from the proximal end for delivering a conductive fluid to the distal end, the distal end of the electrode including an electrically conductive contact element;

wherein the electrode includes a tubular body terminating at the distal end, the tubular body forming at least one passage proximal the distal end, the passage being in fluid communication with the internal lumen;

an electrical insulator surrounding at least a portion of the electrode;

a non-conductive handle rigidly coupled to the proximal end of the electrode such that the distal end of the electrode is readily manipulated in a sliding fashion via movement of the handle;

a source of radiofrequency energy electrically coupled to the electrode; and

a source of conductive fluid fluidly connected to the internal lumen of the electrode.

52. The electrosurgical instrument of claim 51, wherein the contact element is made of metal.

53. The electrosurgical instrument of claim 51, wherein the electrode is made of metal.

54. The electrosurgical instrument of claim 51, wherein the handle is made of sterilizable material.

55. The electrosurgical instrument of claim 51, further comprising wiring electrically connecting the source of radiofrequency energy to the electrode.

56. The electrosurgical instrument of claim 55, wherein the source of radiofrequency energy includes a radiofrequency generator, and further wherein a positive terminal of the radiofrequency generator is electrically coupled to the electrode.

57. The electrosurgical instrument of claim 51, further comprising a suction tube for removing smoke or fluid.

58. The electrosurgical instrument of claim 51, wherein the source of conductive fluid includes a fluid pump.

59. The electrosurgical instrument of claim 51, wherein the source of conductive fluid includes a pressurized canister.

60. The electrosurgical instrument of claim 51, wherein the conductive fluid is selected from the group consisting of saline, saturated saline and Ringer'"'"'s solution.

61. The electrosurgical instrument of claim 51, wherein the conductive fluid includes a dye.

62. The electrosurgical instrument of claim 61, wherein the dye is methylene blue.

63. The electrosurgical instrument of claim 51, wherein the handle is directly mounted to the electrode.

64. An electrosurgical instrument for ablating through a chest of a patient a length of tissue for treating atrial fibrillation, the electrosurgical instrument comprising:

a rigid, elongated electrode having a proximal end, a distal end, and an internal lumen extending from the proximal end for delivering a conductive fluid to the distal end, the distal end of the electrode including an electrically conductive contact element;

wherein the contact element is porous;

an electrical insulator surrounding at least a portion of the electrode;

a non-conductive handle rigidly coupled to the proximal end of the electrode such that the distal end of the electrode is readily manipulated in a sliding fashion via movement of the handle;

a source of radiofrequency energy electrically coupled to the electrode; and

a source of conductive fluid fluidly connected to the internal lumen of the electrode.

65. The electrosurgical instrument of claim 64, wherein the contact element is made of metal.

66. The electrosurgical instrument of claim 64, wherein the electrode is made of metal.

67. The electrosurgical instrument of claim 64, wherein the handle is made of sterilizable material.

68. The electrosurgical instrument of claim 67, further comprising wiring electrically connecting the source of radiofrequency energy to the electrode.

69. A method of performing electrosurgery, comprising the steps of:

(a) applying radio-frequency energy from a source of radio-frequency energy to an electrosurgery site via an electrically conductive contact element at least partially enclosed in an end of an electrically conductive tube connected to the source of radiofrequency energy; and

(b) simultaneously with step (a), infusing the electrosurgery site with a conductive fluid expelled from the tube past the contact element.

70. The method of claim 69, wherein the conductive fluid is cooled before infusing the electrosurgery site with the conductive fluid.

71. The method of claim 69, wherein the conductive fluid is selected from the group consisting of saline, saturated saline and Ringer'"'"'s solution.

72. The method of claim 69, wherein step (b) includes supplying between about 0.5 and about 2 cc per minute conductive fluid.

73. The method of claim 69, wherein step (a) includes supplying about 50 Watts radiofrequency energy.

74. The method of claim 69, wherein step (a) includes supplying about 25 Watts radiofrequency energy.