Electrosurgical electrode with a conductive, non-stick coating

• US 5,925,043 A
• Filed: 04/30/1997
• Issued: 07/20/1999
• Est. Priority Date: 04/30/1997
• Status: Expired due to Term

• Current Assignee: World Heart Corporation (Medtronic Plc), University of Utah (State of Utah)
• Original Assignee: Medquest Products, Inc. (Maverick Venture Management LLC)
• Inventors: Olsen, Don B., Kumar, B. Ajit
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/846,268
• Time in Patent Office: 811 Days
• Field of Search: 606/41, 606/45, 606/48, 606/49, 606/50, 606/51, 606/52, 29/825
• US Class Current: 606/45
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 2017/0088 ceramic
• CPC Class Codes: A61B 2018/00107 Coatings on the energy applicator
• CPC Class Codes: A61B 2018/00119 with metal oxide nitride
• CPC Class Codes: A61B 2018/0013 non-sticking
• CPC Class Codes: A61B 2018/00142 lubricating
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing

Abstract

An electrosurgical blade is provided having a ceramic coating which is conductive, flexible and provides a surface which inhibits the build up of charred tissue. These properties enable the electrosurgical blade to deliver controlled amounts of radio-frequency energy to tissue. The manufacturing process produces a coating of titanium nitride on a stainless steel blade which is amorphous, enabling the electrosurgical blade to bend with the blade in order to perform a wide variety of surgical procedures without damaging the coating. The electrosurgical blade can therefore be used to efficiently cut, coagulate, fulgurate and desiccate tissue. While the blade is primarily used in the monopolar mode, the present invention also encompasses at least two electrosurgical electrodes having the same ceramic coating as the electrosurgical blade, and used in the bipolar mode for coagulation. The coating can be applied on a variety of shapes of electrocautery instruments.

Claims

1. An electrosurgical instrument for use in surgical procedures where it is desired to cut or cauterize tissue utilizing radio frequency energy, and wherein the electrosurgical instrument is comprised of:

a substrate having at least one cutting edge, and wherein the substrate is adapted to be electrically coupled to a source of radio frequency energy which can be directed to the at least one cutting edge; and

a continuous, conductive, ceramic coating disposed on the substrate to thereby cover the at least one cutting edge with an amorphous coating which can flex with the substrate without damaging the continuity of the continuous ceramic coating.

2. The electrosurgical instrument as defined in claim 1 wherein the substrate is further comprised of at least one cauterizing surface, wherein the continuous, conductive, ceramic coating is disposed on the at least one cauterizing surface, and wherein the radio frequency energy can be directed to the at least one cauterizing surface to thereby enable the at least one cauterizing surface to promote hemostasis of tissue with which it comes in contact.

3. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating is sufficiently conductive to enable fulguration of tissue by propagating a spark from the continuous ceramic coating to the tissue.

4. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating is selected from the group of ceramics consisting of transition metal nitrides of which some are (i) amorphous and (ii) conductive.

5. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating is comprised of at least two ceramics which are transition metal nitrides.

6. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating is comprised of (I) at least one ceramic which is a transition metal nitride, and (ii) at least one material which is not a transition metal nitride.

7. The electrosurgical instrument as defined in claim 1 wherein the substrate is composed of a conductive base metal.

8. The electrosurgical instrument as defined in claim 7 wherein the conductive base metal is stainless steel.

9. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating is deposited on the substrate to a thickness of at least 0.1 micrometers.

10. The electrosurgical instrument as defined in claim 1 wherein the continuous ceramic coating does not burn away after repeatedly performing the functions of cutting, cauterizing, fulguration and desiccation.

11. The electrosurgical instrument as defined in claim 1 wherein the at least one cutting edge has generally uniform electrical current density therealong when radio frequency energy is applied to thereto.

12. The electrosurgical instrument as defined in claim 2 wherein the at least one cauterizing surface has generally uniform electrical current density therealong when radio frequency energy is applied to thereto.

13. An electrosurgical instrument for use in surgical procedures where it is desired to coagulate utilizing radio frequency energy, and wherein the electrosurgical instrument is comprised of:

a substrate having a plurality of electrodes at a coagulating end thereof, and wherein the substrate is adapted to be electrically coupled to a source of radio frequency energy which can be directed to the electrodes so as to provide a first path for the radio frequency energy to travel to the electrodes, and a second path for the radio frequency energy to return from the electrodes; and

a continuous, conductive, ceramic coating disposed on the substrate to thereby cover the electrodes with an amorphous coating which can flex with the electrodes without damaging the continuity of the continuous ceramic coating.

14. The electrosurgical instrument as defined in claim 13 wherein the plurality of electrodes have a shape of forceps, tweezers or scissors.

15. A method for providing an electrosurgical instrument that enables electrosurgical procedures to be performed while minimizing thermal damage to tissue, the method comprising the steps of:

a) disposing an amorphous, conductive, ceramic coating on an electrosurgical instrument, wherein the amorphous, conductive, ceramic coating resists build up of charred tissue thereon so that the at least one electrosurgical procedure can be performed using a minimum level of radio frequency energy applied to the electrosurgical instrument; and

b) performing the functions of cutting, cauterizing, fulguration or desiccation during the electrosurgical procedures by using the electrosurgical instrument which minimizes thermal damage to tissue.

16. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the step of disposing an amorphous ceramic coating includes the step of applying a ceramic coating from the group of ceramics consisting of transition metal nitrides of which some are (i) amorphous and (ii) conductive.

17. The method for performing at least one electrosurgical procedure as defined in claim 16 wherein the step of disposing an amorphous and ceramic coating includes the step of applying at least two ceramics which are transition metal nitrides.

18. The method for performing the at least one electrosurgical procedure as defined in claim 16 wherein the step of disposing an amorphous and ceramic coating includes the steps of applying:

(i) at least one ceramic which is a transition metal nitride; and

(ii) at least one material which is not a transition metal nitride.

19. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the method further includes the step of applying an amorphous ceramic coating which is not worn away by application of RE energy, by scrubbing or by repeated sterilization of the amorphous ceramic coating.

20. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the method of performing at least one electrosurgical procedure includes the step of performing an electrosurgical procedure which requires that the electrosurgical instrument be deformed from a resting state, and wherein the amorphous ceramic coating is deformed with the electrosurgical instrument without damage to the amorphous ceramic coating.

21. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the method further includes the step of minimizing plumes during the at least one electrosurgical procedure by preventing build up of charred tissue on the electrosurgical instrument by using an amorphous ceramic coating thereon.

22. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the method further includes the step of reducing introduction of foreign body contamination in a surgical field by reducing build up of charred tissue on the electrosurgical instrument which can break away therefrom during the at least one electrosurgical procedure.

23. The method for performing the at least one electrosurgical procedure as defined in claim 15 wherein the method further includes the step of creating a controlled incision in the tissue by reducing build up of charred tissue on the electrosurgical instrument.

24. A method of manufacturing an electrosurgical instrument for use in surgical procedures where it is desired to cut or cauterize tissue utilizing radio frequency energy, the method comprising the steps of:

(1) providing a substrate having at least one cutting edge, and wherein the substrate is adapted to be electrically coupled to a source of radio frequency energy which can be directed to the at least one cutting edge; and

(2) depositing a thin, conductive, continuous, amorphous ceramic coating on the substrate, wherein the thin, conductive, continuous, amorphous ceramic coating is capable of being deformed integrally with the electrosurgical instrument without sustaining damage thereto.

25. The method of manufacturing as defined in claim 24 wherein the method comprises the further step of depositing the amorphous ceramic coating using room or near room temperature sputtering.

26. The method of manufacturing as defined in claim 24 wherein the step of depositing the thin, conductive, continuous, amorphous coating further comprises the steps of:

(1) substituting titanium nitride as the coating; and

(2) sputtering the titanium nitride onto the substrate.

27. An electrosurgical instrument for use in surgical procedures where it is desired to cut or cauterize tissue utilizing radio frequency energy, and wherein the electrosurgical instrument is comprised of:

a substrate having at least one means for cutting/coagulation, and wherein the substrate is adapted to be electrically coupled to a source of radio frequency energy which can be directed to the at least one cutting/coagulation means; and

a continuous, conductive, ceramic coating disposed on the substrate to thereby cover the at least one cutting/coagulation means with an amorphous coating which can flex with the substrate without damaging the continuity of the continuous ceramic coating.

28. The electrosurgical instrument as defined in claim 27 wherein the at least one cutting/coagulation means is selected from the group of cutting/coagulation means consisting of a loop, square, ball, blade, triangle, diamond and needle.

29. An electrosurgical instrument for use in surgical procedures where it is desired to cut or cauterize tissue utilizing radio frequency energy, and wherein the electrosurgical instrument is comprised of:

a substrate having a working end, wherein the working end is adapted to be electrically coupled to a source of radio frequency energy which can be directed to the working end; and

a continuous, conductive, ceramic coating disposed on the substrate to thereby cover the working end with an amorphous coating which can flex with the substrate without damaging the continuity of the continuous ceramic coating.