Electrosurgical forceps

• US 5,891,142 A
• Filed: 06/18/1997
• Issued: 04/06/1999
• Est. Priority Date: 12/06/1996
• Status: Expired due to Term

• Current Assignee: Intuitive Surgical Operations, Inc. (Intuitive Surgical Holdings, LLC)
• Original Assignee: Eggers & Associates, Inc.
• Inventors: Eggers, Philip E., Eggers, Andrew R.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/878,400
• Time in Patent Office: 657 Days
• Field of Search: 606/50-52, 606/43
• US Class Current: 606/51
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 2017/0088 ceramic
• CPC Class Codes: A61B 2018/00107 Coatings on the energy applicator
• CPC Class Codes: A61B 2018/00136 with polymer
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/143 multiple needles
• CPC Class Codes: A61B 2018/1462 Tweezers

Abstract

Surgical forceps which are configured having oppositely disposed tissue grasping surfaces at the tip regions of corresponding tines. An electrically insulative spacer assembly is positioned on and supported from at least one of the tissue grasping surfaces to space the tissue contacting surfaces apart an optimized distance, T, when the tines are in a substantially closed orientation. A preferred, strip form of spacer assembly formed of an electrically insulative material is employed and improved current paths are defined between the grasping surfaces to derive an efficient and effective hemostasis substantially without sticking of tissue to the surfaces. The geometric configuration of the spacer regions functions to enhance cleanability of the forceps and the tines of the forceps additionally are formed with side and nose surfaces at the tip regions having effective side surface current delivery areas improving forceps performance when used in a coagulative painting modality.

Claims

1. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive tissue grasping surface with a first periphery of predetermined shape;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive tissue grasping surface with a periphery of predetermined shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open tankard a closed orientation for grasping said tissue; and

at least two, electrically insulative, spaced apart spacer regions mounted upon at least one said grasping surface for spacing said electrically conductive surfaces apart a distance, T, when substantially in said closed orientation effective to derive a substantially uniform power density along current paths between said surfaces and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing and said spacer regions having a geometry effective to securely grasp and extrude said tissue into electrically conducting contact with each interstitial contact surface adjacent said spacer regions at said grasping surfaces to derive said current paths and avoid slippage from said tissue during its surgical manipulation.

2. The surgical forceps of claim 1 in which said distance, T, is less than about 0.020 inch.

3. The surgical forceps of claim 1 in which said distance, T, is less than or equal to about 0.010 inch.

4. The surgical forceps of claim 1 in which said distance, T, has a minimum value of about 0.003 inch.

5. The surgical forceps of claim 1 in which said electrically insulative spaced apart spacer regions are parallel strips of insulative material.

6. The surgical forceps of claim 1 in which said electrically insulative spaced apart spacer regions are parallel strips of insulative material fixed to said grasping surface at said first tip region and having a thickness corresponding with said distance, T.

7. The surgical forceps of claim 6 in which:

said first tine extends to a first tip periphery of said first tip region;

said second tine extends to a second tip periphery of said second tip region;

said parallel strips of insulative material extend across the said first periphery of said grasping surface transversely to the longitudinal extent of said first tine; and

one said strip of insulative material is located at said first tip periphery to provide a tissue snagging function.

8. The surgical forceps of claim 7 in which:

said first and second tip regions are formed of a thermally conductive, biologically compatible metal; and

said first and second tip regions are coated with an electro-deposited biocompatible metallic layer.

9. The surgical forceps of claim 6 in which said parallel strips of insulative material extend in substantially parallel relationship with the longitudinal extent of said first tine.

10. The surgical forceps of claim 1 in which said electrically insulative spaced apart regions comprise:

a first array of parallel strips of insulative material fixed to said grasping surface at said first tip region and having a thickness, T1;

a second array of strips of insulative material fixed to said grasping surface at said second tip region, said strips thereof having a thickness, T2, and being aligned for movement into mutual contact with corresponding strips of said first array when said first and second tip regions are in a said closed orientation; and

the sum of said thickness'"'"', T1 and T2 corresponds with said distance, T.

11. The surgical forceps of claim 1 in which:

said electrically insulative spaced apart spacer regions are first parallel strips of insulative material fixed to said grasping surface at said first tip region; and

second parallel strips of insulative material fixed to said grasping surface at said second tip region; and

said first parallel strips and second parallel strips having thicknesses deriving said distance, T.

12. The surgical forceps of claim 1 in which said electrically insulative spaced apart spacer regions are configured as an array of discrete, spaced apart cubes.

13. The surgical forceps of claim 1 in which said electrically insulative, spaced apart spacer regions are configured as an array of discrete, spaced apart circular layers.

14. The surgical forceps of claim 1 in which each said tine tip region is configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component;

said spacer regions are deposited upon and supported by a said biocompatible component.

15. The surgical forceps of claim 14 in which said thermally conductive component is copper, said biocompatible component is stainless steel, and said spacer regions are formed of alumina.

16. The surgical forceps of claim 14 in which said composite is provided as a bonded copper and stainless steel laminate having a copper content of about 50% to 90% by volume.

17. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive metal first tissue grasping surface;

a second tine connectable with said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive metal second tissue grasping surface, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon said second tip region metal second tissue grasping surface and having a configuration with said first tissue grasping surface for spacing them apart a distance, T, when said first and second tines are in said closed orientation, the geometric surface shape of said configuration and said distance, T, being effective to establish electrical contact between metal tissue grasping surface exposed portions of said second tissue grasping surface at said second tip region and grasped tissue and to derive current paths defining a substantially uniform power density, between said first and second tissue grasping surfaces and through grasped tissue therebetween of lengths not exceeding a value achieving effective coagulation of said grasped tissue, said geometric surface shape being effective to securely grasp and extrude said tissue into electrically conducting contact with each said first and second tissue grasping surface.

18. The surgical forceps of claim 17 in which said electrically insulative spacer assembly spacing distance, T, has a minimum value of about 0.003 inch.

19. The surgical forceps of claim 17 in which said electrically insulative spacer assembly comprises at least one strip of insulative material fixed to said second electrically conductive metal tissue grasping surface.

20. The surgical forceps of claim 17 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips disposed normally to the longitudinal extent of said second tine, one said strip being located at the longitudinally outermost portion of said first tissue grasping surface.

21. The surgical forceps of claim 20 in which at least one said first and second tissue grasping surface includes a portion adjacent said spacer assembly with a biocompatible surface coating formed of polytetrafluoroethylene polymer or copolymer.

22. The surgical forceps of claim 21 in which said surface coating contains metal particles.

23. The surgical forceps of claim 17 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips disposed in parallel relationship with the longitudinal extent of said second tine.

24. The surgical forceps of claim 17 in which said electrically insulative spacer assembly is configured as an array of discrete spaced apart cubes.

25. The surgical forceps of claim 17 in which said electrically insulative spacer assembly is configured as an array of discrete spaced apart circular layers.

26. The surgical forceps of claim 17 in which at least one of said first and second tissue grasping surfaces includes a portion adjacent said spacer assembly with a biocompatible surface coating formed of a polytetrafluoroethylene polymer or copolymer.

27. The surgical forceps of claim 26 in which said biocompatible surface coating contains metal particles.

28. The surgical forceps of claim 17 in which each said tine tip region is configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component;

said spacer assembly is deposited upon and supported by a said biocompatible component.

29. The surgical forceps of claim 28 in which said thermally conductive component is copper, said biocompatible component is stainless steel, and said spacer assembly is formed of alumina.

30. The surgical forceps of claim 28 in which said composite is provided as a bonded copper and stainless steel laminate having a copper content of about 50% to 90% by volume.

31. Surgical forceps connectable with the bipolar output of an electrosurgical generator having a power output to load impedance characteristic exhibiting a preferred load impedance range for effecting hemostasis of grasped tissue, comprising:

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive first tissue grasping surface with a first periphery of predetermined shape;

a second tine connectable with said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive second tissue grasping surface with a second periphery of predetermined shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly fixed to at least one said first and second tissue grasping surface and having a configuration for spacing said first and second grasping surfaces apart a distance, T, when said first and second tines are in said closed orientation, said distance, T, and the surface configuration of said spacer assembly being selected to derive a load impedance with respect to said grasped tissue within said desired load impedance range when said first and second grasping surfaces are grasping tissue while spaced apart substantially about said distance, T, said configuration being effective to derive current paths between said first and second grasping surfaces corresponding with said load impedance and said spacer assembly, having a geometry effective to securely grasp and extrude said tissue into electrically conducting contact with each interstitial contact surface adjacent said spacer assembly at said grasping surfaces to derive said current paths and avoid slippage from said tissue during its surgical manipulation.

32. The surgical forceps of claim 31 in which said electrically insulative spacer assembly spacing distance, T, has minimum value of about 0.003 inch.

33. The surgical forceps of claim 31 in which said electrically insulative spacer assembly comprises at least one strip of insulative material fixed to said first tissue grasping surface at the outermost periphery of said first tip region longitudinal extent.

34. The surgical forceps of claim 39 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips located upon said first tissue grasping surface and disposed normally to the longitudinal extent of said first tine.

35. The surgical forceps of claim 31 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips located upon said first tissue grasping surface and disposed in parallel relationship with the longitudinal extent of said first tine.

36. The surgical forceps of claim 31 in which said electrically insulative spacer assembly is configured as an array of discrete spaced apart cubes.

37. The surgical forceps of claim 31 in which said electrically insulative spacer assembly is configured as an array of discrete spaced apart circular layers.

38. The surgical forceps of claim 31 in which:

said first tine first tip region is of generally rectangular cross-section, one surface of which is said first tissue grasping surface having a width, L1, transverse to the longitudinal extent of said first tine and having a first side surface of an effective length, L2, disposed at an angle, α

, with respect to said first tissue grasping surface;

said second tine second tip region is of generally rectangular cross-section, one surface of which is said second tissue grasping surface having a width, L1, transverse to the longitudinal extent of said second tine and having a second side surface of an effective length, L3, disposed at said angle, α

with respect to said second tissue grasping surface; and

said angle, α

is selected from within a range of between about 80° and

100°

establishing adjacent said first and second side surfaces at respective said first and second tip regions having said effective lengths L2 and L3 with values effective to provide hemostasis in tissue when in sliding contact with them, said effective lengths L2 and L3 having values selected to evoke load impedances substantially within said preferred impedance range.

39. The surgical forceps of claim 38 the ratio of said width L1, to each said effective lengths L2 and L3 is within a range of about 0.25 to 10.

40. The surgical forceps of claim 31 in which each said tine tip region is configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component;

said spacer regions are deposited upon and supported by a said biocompatible component.

41. The surgical forceps of claim 40 in which said thermally conductive component comprises copper, said biocompatible component comprises stainless steel, and said spacer assembly comprises alumina.

42. The surgical forceps of claim 40 in which said composite is provided as a bonded copper and stainless steel laminate having a copper content of about 50% to 90% by volume.

43. Surgical forceps connectable with the bipolar output of an electrosurgical generator for contacting tissue to effect hemostasis, said generator exhibiting a given power output to load impedance characteristic having an impedance range of efficient coagulation performance comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region of generally rectangular cross-section, one surface of which is an inwardly disposed electrically conductive tissue grasping surface having a width, L1, transverse to said longitudinal extent and having a first side surface of an effective length, L2, disposed at an angle, α

with respect to said tissue grasping surface;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region of generally rectangular cross-section and one surface of which is an inwardly disposed electrically conductive tissue grasping surface having a said width, L1, transverse to said longitudinal extent and having a second side surface of an effective length, L3, disposed at said angle, α

with respect to said tissue grasping surface of said second tip region, said first and second tip regions and said first and second side surfaces being mutually oppositely disposed in substantial alignment and said first and second tip regions being relatively movable from an open toward a closed orientation for grasping said tissue;

an electrically insulative spacer assembly fixed to at least one said tissue grasping surface for spacing said electrically conducting tissue grasping surfaces apart a distance, T, when said first and second tines substantially are in said closed orientation; and

said angle, α

is selected from within a range between about 80° and

100°

establishing adjacent said first and second side surfaces at respective said first and second tip regions having said effective lengths L2 and L3 with values effective to provide hemostasis in tissue in sliding contact with them, said effective lengths. L2 and L3, having values selected to evoke load impedances substantially within said impedance range.

44. The surgical forceps of claim 43 in which the ratio of said width, L1, to each said effective lengths L2 and L3 is within a range of about 0.25 to 10.

45. The surgical forceps of claim 43 in which the ratio of said width L1, to each said effective lengths L2 and L3 is within a range of about 0.4 to 5.

46. The surgical forceps of claim 43 in which said electrically insulative spacer assembly has a configuration to provide said distance, T, at a value effective to establish electrical contact between the exposed portions of said metal tissue grasping surfaces and tissue grasped thereby to derive current paths defining a substantially uniform power density between said tissue grasping surfaces and through grasped tissue therebetween of length not exceeding a value achieving effective coagulation of said grasped tissue.

47. The surgical forceps of claim 46 in which said distance, T, has a minimum value of about 0.003 inch.

48. The method for grasping a select component of tissue of a body and effecting hemostasis at such tissue comprising the steps of:

providing an electrosurgical generator controllable to have a bipolar output;

providing surgical forceps, including;

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive metal first tissue grasping surface,

a second tine connectable with said output and extending longitudinally to a second tip region having an inwardly disposed electrically conductive metal second tissue grasping surface, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue, and

an electrically insulative spacer assembly mounted upon at least one said first and second tissue grasping surface and having a configuration for spacing them apart a distance, T, when said first and second tines substantially are in said closed orientation, the geometric surface shape of said configuration and said distance, T, being effective to derive current paths defining a substantially uniform power density between said surfaces and through grasped tissue of lengths not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing, said geometric surface shape being effective to securely grasp and extrude said tissue into electrically conducting contact with each said grasping surface;

grasping said component of tissue between said first and second tip regions by manually urging said first and second tines toward said closed orientation such that said component of tissue is extruded into contact with said metal first tissue grasping surface and said second metal tissue grasping surface to an extent said length is substantially derived; and

controlling said electrosurgical generator to convey current from said output to said first and second tines to establish current flow along said current path for an interval effective to establish said hemostasis.

49. The method of claim 48 in which said electrically insulative spacer assembly configuration provides said distance, T, as having a value less than about 0.020 inch.

50. The method of claim 48 in which said electrically insulative spacer assembly configuration provides said distance, T, as having a value less than or equal to about 0.010 inch.

51. The method of claim 48 in which said electrically insulative spacer assembly configuration provides a distance, T, as having a minimum value of about 0.003 inch.

52. The method of claim 48 in which:

said electrosurgical generator is provided having a power output to load impedance characteristic exhibiting a preferred load impedance range for effecting hemostasis of said tissue component; and

said electrically insulated spacer assembly established distance, T, is effective to derive said current path between said first and second tissue grasping surfaces and through said tissue component of length not exceeding a value achieving effective coagulation of said grasped tissue and establishing a load impedance through said grasped tissue within said preferred load impedance range.

53. The method of claim 48 in which said electrically insulative spacer assembly is provided as parallel strips of insulative material fixed to at least one said first and second tissue grasping surface.

54. The method for effecting hemostasis at the surface of tissue comprising the steps of:

providing an electrosurgical generator controllable to have an output, said generator exhibiting a given power output to load impedance characteristic having an impedance range of efficient coagulation performance,

providing surgical forceps, including;

a first tine connectable with said output and extending longitudinally to a first tip region of generally rectangular cross-section, one surface of which is an inwardly disposed electrically conductive tissue grasping surface having a width, L1, transverse to said longitudinal extent and having a first side surface of an effective length, L2, disposed at an angle, α

, with respect to said tissue grasping surface,

a second tine connectable with said output and extending longitudinally to a second tip region of generally rectangular cross-section and one surface of which is an inwardly disposed electrically conductive tissue grasping surface, having a said width, L1, transverse to said longitudinal extent and having a second side surface of an effective length, L3, disposed at said angle, α

, with respect to said tissue grasping surface of said second tip region, said first and second tip regions and said first and second side surfaces being mutually oppositely disposed in substantial alignment and said first and second tip regions being relatively movable from an open toward a closed orientation for grasping said tissue,

an electrically insulative spacer assembly fixed to at least one said tissue grasping surface for spacing said electrically conducting tissue grasping surfaces apart a distance, T, when said first and second tines substantially are in closed orientation, and

said angle, α

, is selected from within a range between about 80° and

100°

establishing adjacent said first and second side surfaces at respective said first and second tip regions having said effective lengths L2 and L3 with values effective to provide hemostasis in tissue in sliding contact with them said effective lengths, L2 and L3 having values selected to evoke load impedances substantially within said impedance range;

manually moving said first and second tines substantially into said closed orientation;

contacting said surface simultaneously with said first and second side surfaces while said first and second tines are substantially in said closed orientation;

controlling said electrosurgical generator to convey current from said output to said first and second tines to establish a flow of current from said first side surface, through said tissue to said second side surface to effect said hemostasis; and

moving said forceps to deliver said effected hemostasis along a predetermined path while said first and second tines are substantially in said closed orientation and said flow of current is established.

55. The method of claim 54 in which said surgical forceps are provided wherein the ratio of said width, L1, to each said effective lengths L2 and L3 is within a range of about 0.25 to 10.

56. The method of claim 54 in which said surgical forceps are provided wherein the ratio of said width, L1, of said effective lengths, L2 and L3, is within a range of about 0.4 to 5.

57. The method of claim 54 in which said electrically insulative spacer assembly provides said distance, T, as having a value less than about 0.020 inch.

58. The method of claim 54 in which said electrically insulative spacer assembly provides said distance, T, as having a value less than or equal to about 0.010 inch.

59. The method of claim 54 in which said electrically insulative spacer assembly provides a distance, T, as having a minimum value of about 0.003 inch.

60. Surgical forceps connectable with the output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region, said first tip region being a first laminar composite having a first thermally conductive outwardly disposed metal component bonded with a first biocompatible, electrically conductive metal inwardly disposed component configured to provide a first tissue grasping region,

a second tine connectable with said output and extending longitudinally to a second tip region, said second tip region being a second laminar component having a second thermally conductive outwardly disposed metal component bonded with a second biocompatible electrically conductive metal inwardly disposed component configured to provide a second tissue grasping region, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon at least one said first and second tissue grasping region respective first and second biocompatible electrically conductive metal component and having a configuration for spacing them apart a distance, T, when said firs and second tines are in said closed orientation, the geometric surface shape of said configuration, and said distance, T, being effective to derive a substantially uniform power density along current paths between said first an second regions and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing, and said spacer assembly, having a geometry effective to securely grasp and extrude said tissue into electrically conducting contact with each interstitial contact surface adjacent said spacer assembly at said grasping regions to derive said current paths and avoid slippage from said tissue during its surgical manipulation.

61. The surgical forceps of claim 60 in which said first and second thermally conductive metal components comprise copper and said first and second biocompatible electrically conductive components comprise stainless steel.

62. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive metal first tissue grasping surface;

a second tine connectable with said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed second electrically conductive metal tissue grasping surface, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon at least one said first and second tip region metal tissue grasping surface and having a configuration for spacing them apart a distance, T, when said first and second tines are in said closed orientation, said distance, T, being limited to an extent effective to cause the extrusion of said tissue into intimate electrical contact with each said first and second tissue grasping surfaces when said first and second tip regions are moved toward said closed orientation to define current paths between said first and second tissue grasping surfaces and through grasped tissue therebetween deriving uniform power density and achieving effective coagulation of said grasped tissue.

63. The surgical forceps of claim 62 in which said electrically insulative spacer assembly spacing distance, T, has a minimum value of about 0.003 inch.

64. The surgical forceps of claim 62 in which said electrically insulative spacer assembly comprises at least one strip of insulative material fixed to a said first or second electrically conductive metal tissue grasping surface.

65. The surgical forceps of claim 62 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips disposed normally to the longitudinal extent of a said first or second tine upon which it is mounted, one of said strips being located at the longitudinally outermost portion of said first tissue grasping surface.

66. The surgical forceps of claim 62 in which said electrically insulative spacer assembly comprises an array of spaced apart parallel strips disposed in parallel relationship with the longitudinal extent of a said first or second tine upon which it is mounted.

67. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive tissue grasping surface with a first periphery of predetermined shape and configured to provide said electrically conductive surface as a first array of sequentially disposed grooves and lands;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive tissue grasping surface with a periphery of predetermined shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping said tissue, and said second tip region being configured to provide said electrically conductive surface as a second array of sequentially disposed grooves and lands displaced along the longitudinal extent of said second tine with respect to said first array an amount effective to align each said groove of said first array with a corresponding said land of said second array; and

at least two, electrically insulative, spaced apart spacer regions mounted upon at least one said grasping surface for spacing said electrically conductive surfaces apart a distance, T, when substantially in said closed orientation effective to derive a current path between said surfaces and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing, said spacer regions being located only within the said grooves of said second array.

68. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive tissue grasping surface with a first periphery of predetermined shape, said first tip region being configured having an array of discrete, spaced apart holes of circular peripheral shape;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive tissue grasping surface with a periphery of predetermined shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping said tissue; and

at least two, electrically insulative, spaced apart spacer regions provided as discrete pegs mounted within said spaced apart holes and spacing said electrically conductive surfaces apart a distance, T, when substantially in said closed orientation, effective to derive a current path between said surfaces and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing.

69. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive tissue grasping surface with a first periphery of predetermined shape and extending to a first tip periphery, and including an inwardly depending tooth located at said tip periphery and having a predetermined tooth length;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive tissue grasping surface with a periphery of predetermined shape and extending to a second tip periphery, including a recess at said tip periphery extending to a bottom surface at a depth corresponding with said predetermined tooth length having a configuration corresponding with said tooth, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping said tissue;

an electrically insulative, spaced apart spacer region mounted upon at least one said grasping surface for spacing said electrically conductive surfaces apart a distance, T, when substantially in said closed orientation effective to derive a current path between said surfaces and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing; and

said bottom surface of said second tip region being spaced in electrically insulative relationship from said tooth said distance, T, in the presence of said substantially closed orientation.

70. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with a said output of first polarity and extending longitudinally to a first tip region configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component, said first tip region having an inwardly disposed electrically conductive tissue grasping surface with a first periphery of predetermined shape;

a second tine connectable with a said output of second polarity and extending longitudinally to a second tip region configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component, said second tip region having an inwardly disposed electrically conductive tissue grasping surface with a periphery of predetermined shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping said tissue; and

at least two electrically insulative, spaced apart spacer regions deposited upon and supported by at least one said biocompatible component for spacing said electrically conductive surfaces apart a distance, T, when substantially in said closed orientation effective to derive a current path between said surfaces and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing; and

said composite being coated with an electro-deposited biocompatible metallic layer to provide said grasping surfaces.

71. Surgical forceps connectable with the output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having an inwardly disposed electrically conductive metal first tissue grasping surface;

a second tine connectable with said output and extending longitudinally to a second tip region having an inwardly disposed second electrically conductive metal tissue grasping surface, and configured having an array of discrete, spaced apart holes of circular peripheral shape, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon said second tip region metal tissue grasping surface comprising discrete pegs mounted within said spaced apart holes and extending outwardly from said second electrically conductive metal tissue grasping surface, and having a configuration with said first tissue grasping surface for spacing them apart a distance, T, when said first and second tines are in said closed orientation, the geometric surface shape of said configuration and said distance, T, being effective to establish electrical contact between metal tissue grasping surface exposed portions of said second surface at said second tip region and grasped tissue and to derive a current path between said first and second tissue grasping surfaces and through grasped tissue therebetween of length not exceeding a value achieving effective coagulation of said grasped tissue.

72. Surgical forceps connectable with the output of an electrosurgical generator for grasping tissue and for effecting hemostasis comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having a tip periphery and an inwardly disposed electrically conductive metal first tissue grasping surface, and including an inwardly depending tooth located at said tip periphery and having a predetermined tooth length extending to an engaging surface;

a second tine connectable with said output and extending longitudinally to a second tip region having a tip periphery and an inwardly disposed second electrically conductive metal tissue grasping surface, including a recess extending a length corresponding with said predetermined tooth length to a bottom surface and configured in correspondence with said tooth, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly comprising an insulative coating located at said recess bottom surfaced having a thickness for spacing said engaging surface from said bottom surface a distance, T, when said first and second tines are in said closed orientation, said distance, T, being effective to establish electrical contact between metal tissue grasping surface exposed portions of said second surface at said second tip region and grasped tissue and to derive a current path between said first and second tissue grasping surfaces and through grasped tissue therebetween of length not exceeding a value achieving effective coagulation of said grasped tissue.

73. Surgical forceps connectable with the output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having a tip periphery and an inwardly disposed electrically conductive metal first tissue grasping surface and including an inwardly depending tooth located at said tip periphery and having a predetermined tooth length extending to a tooth end;

a second tine connectable with said output and extending longitudinally to a second tip region having a tip periphery and an inwardly disposed second electrically conductive metal tissue grasping surface including a recess extending to a bottom surface at a depth corresponding, with said predetermined tooth length, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon said second tip region metal tissue grasping surface and having a configuration spacing said tooth end from said bottom surface a distance, T, when said first and second tines are in said closed orientation, the geometric;

surface shape of said configuration and said distance, T, being effective to establish electrical contact between metal tissue grasping surface exposed portions of said second surface at said second tip region and grasped tissue and to derive a current path between said first and second tissue grasping surfaces and through grasped tissue therebetween of length not exceeding a value achieving effective coagulation of said grasped tissue.

74. Surgical forceps connectable with the output of an electrosurgical generator having a power output to load impedance characteristic exhibiting a preferred load impedance range for effecting hemostasis of grasped tissue, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having an inwardly disposed electrically conductive first tissue grasping surface with a first periphery of predetermined shape extending to a tip periphery and including an inwardly depending tooth located in said tip periphery and having a predetermined tooth length extending to an engaging surface;

a second tine connectable with said output and extending longitudinally to a second tip region having an inwardly disposed electrically conductive second tissue grasping surface with a second periphery of predetermined shape, extending to a tip periphery, including a recess extending a length corresponding with said predetermined length to a bottom surface and configured in correspondence with said tooth, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly fixed to at least one said first and second tissue grasping surface comprising an insulative coating located at said recess bottom surface having a thickness for spacing said engaging surface from said bottom surface a distance, T, when said first and second tines are in said closed orientation, said distance, T, and the surface configuration of said spacer assembly being selected to derive a load impedance within said desired load impedance range when said first and second grasping surfaces are grasping tissue while spaced apart substantially about said distance, T.

75. Surgical forceps connectable with the output of an electrosurgical generator having a power output to load impedance characteristics exhibiting a preferred load impedance range for effecting hemostasis of grasped tissue, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having an inwardly disposed electrically conductive first tissue grasping surface with a first periphery of predetermined shape, extending to a tip periphery and including an inwardly depending tooth located at said tip periphery having a predetermined tooth length extending to a tooth end;

a second tine connectable with said output and extending longitudinally to a second tip region having and an inwardly disposed electrically conductive second tissue grasping surface with a second periphery of predetermined shape, extending to a tip periphery and including a recess extending to a bottom surface at a depth corresponding with said predetermined tooth length;

said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly fixed to at least one said first and second tissue grasping surface and having a configuration for spacing said tooth end from said bottom surface a distance, T;

when said first and second tines are in said closed orientation, said distance, T, and the surface configuration of said spacer assembly being selected to derive a load impedance within said desired load impedance range when said first and second grasping surfaces are grasping tissue while spaced apart substantially about said distance, T.

76. Surgical forceps connectable with the output of an electrosurgical generator having a power output to load impedance characteristic exhibiting a preferred load impedance range for effecting hemostasis of grasped tissue, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region having an inwardly disposed electrically conductive first tissue grasping surface with a first periphery of predetermined shape, said first tip region being configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component;

a second tine connectable with said output and extending longitudinally to a second tip region having an inwardly disposed electrically conductive second tissue grasping surface with a second periphery of predetermined shape, said second tip region being configured as a laminar composite having a thermally conductive component bonded with an inwardly disposed biocompatible component, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue;

an electrically insulative spacer assembly fixed to at least one said first and second tissue grasping surface at said biocompatible component and having a configuration for spacing said first and second grasping surfaces apart a distance, T, when said first and second tines are in said closed orientation, said distance, T, and the surface configuration of said spacer assembly being selected to derive a load impedance within said desired load impedance range when said first and second grasping surfaces are grasping tissue while spaced apart substantially about said distance, T; and

said composite being coated with an electro-deposited biocompatible metallic layer.

77. The surgical forceps of claim 76 in which said electrically insulative spacer assembly is an alumina deposit.

78. Surgical forceps connectable with the output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output and extending longitudinally to a first tip region, said first tip region being a first laminar composite having a first thermally conductive outwardly disposed copper metal component bonded with a first biocompatible, electrically conductive stainless steel metal inwardly disposed component configured to provide a first tissue grasping region;

a second tine connectable with said output and extending longitudinally to a second tip region, said second tip region being a second laminar component having a second thermally conductive outwardly disposed copper metal component bonded with a second biocompatible, electrically conductive stainless steel metal inwardly disposed component configured to provide a second tissue grasping region, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue;

an electrically insulative spacer assembly mounted upon at least one said first and second tissue grasping region first and second biocompatible electrically conductive metal component and having a configuration for spacing them apart a distance, T, when said first and second tines are in said closed orientation, the geometric surface shape of said configuration and said distance, T, being effective to derive current paths between said first and second regions and through grasped tissue of length not exceeding a value achieving effective coagulation of said grasped tissue while avoiding arcing; and

each said first and second laminar composites being coated with an electro-deposited layer of biocompatible metal.

79. Surgical forceps connectable with the bipolar output of an electrosurgical generator for grasping tissue and for effecting hemostasis, comprising:

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive metal first tissue grasping surface extending to an outer tip periphery of said first tip region;

a second tine connectable with said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed second electrically conductive metal tissue grasping surface, extending to an outer tip periphery said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue; and

an electrically insulative spacer assembly mounted upon said first tip region metal tissue grasping surface including a first array of parallel strips of insulative material fixed to said first tissue grasping surface at said first tip region, extending transversely to the longitudinal extent of said first tine, one said strip of insulative, material being located at said outer periphery of said first tip, said first array of parallel strips having a configuration with respect to said second grasping surface for spacing them apart a distance, T, when said first and second tines are in said closed orientation, said distance, T, being effective to establish electrical contact between metal tissue grasping surface exposed portions of said first surface at said first tip region and grasped tissue and to define a substantially uniform power density between said first and second tissue grasping surfaces and through grasped tissue therebetween achieving effective coagulation of said grasped tissue, said array of strips being effective to securely grasp and extrude said tissue into electrically conducting contact with each said first and second grasping surface; and

said first and second tissue grasping surface being coated with an electro-deposited biocompatible metallic layer.

80. The surgical forceps of claim 79 in which said spacer assembly includes a second array of parallel strips of insulative material fixed to said second tissue grasping surface.

81. The surgical forceps of claim 79 in which said electrically insulative spacer assembly spacing distance, T, has a minimum value of about 0.003 inch.

82. The surgical forceps of claim 79 in which:

said generator exhibits given power output to load impedance characteristics having an impedance range of efficient coagulation performance;

said first tine first tip region is of generally rectangular cross-section, one surface of which is said first tissue grasping surface having a width, L1, transverse to the longitudinal extent of said first tine and having a first side surface of an effective length, L2, disposed at an angle, α

, with respect to said first tissue grasping surface;

said second tine second tip region is of generally rectangular cross-section, one surface of which is said second tissue grasping surface having a width, L1, transverse to the longitudinal extent of said second tine and having a second side surface of an effective length, L3, disposed at said angle α

, with respect to said second tissue grasping surface;

said angle, α

, is selected from within a range of between about 80° and

100°

establishing adjacent said first and second side surfaces at respective said first and second tip regions having said effective lengths L2 and L3 with values effective to provide hemostasis in tissue when in sliding contact with them; and

said effective lengths L2 and L3 have values selected to evoke load impedances substantially within said impedance range.

83. The surgical forceps of claim 79 in which said biocompatible layer comprises a surface coating formed of polytetrafluoroethylene polymer or copolymer.

84. The surgical forceps of claim 83 in which said surface coating contains metal particles.

85. Surgical forceps connectable with the bipolar output of an electrosurgical generator having a power output to load impedance characteristic exhibiting a preferred load impedance range for effecting hemostasis of grasped tissue, comprising:

a first tine connectable with said output of first polarity and extending longitudinally to a first tip region having an inwardly disposed electrically conductive first tissue grasping surface with a first periphery of predetermined shape and extending to a tip periphery;

a second tine connectable with said output of second polarity and extending longitudinally to a second tip region having an inwardly disposed electrically conductive second tissue grasping surface with a second periphery of predetermined shape and extending to a tip periphery, said first and second tip regions being mutually oppositely disposed in alignment and relatively movable from an open toward a closed orientation for grasping tissue;

an electrically insulative spacer assembly fixed to at least one said first and second tissue grasping surface and having a configuration for spacing said first and second grasping surfaces apart a distance, T, when said first and second tines are in said closed orientation, said spacer assembly including a first array of parallel strips of insulative material fixed to said first tissue grasping surface at said first tip region, extending transversely to the longitudinal extent of said first tine, one said strip of insulative material being located at said outer periphery of said first tip, said distance, T, being selected to derive a load impedance within said desired load impedance range when said first and second grasping surfaces are grasping tissue while spaced apart substantially about said distance, T, said configuration being effective to derive current paths between said first and second grasping surfaces corresponding with said load competence; and

said first and second tissue grasping surfaces being coated with an electro-deposited, biocompatible metallic layer.

86. The surgical forceps of claim 85 in which said electrically insulative spacer assembly spacing distance, T, has minimum value of about 0.003 inch.

87. The surgical forceps of claim 86 in which said spacer assembly includes a second array of parallel strips of insulative material fixed to said second tissue grasping surface.