Abherent surgical instrument and method

• US 4,848,337 A
• Filed: 06/13/1986
• Issued: 07/18/1989
• Est. Priority Date: 09/10/1979
• Status: Expired due to Term

• Current Assignee: Hemostatic Surgery Corporation
• Original Assignee: Hemostatic Surgery Corporation
• Inventors: Eggers, Philip E., Shaw, Robert F.
• Primary Examiner(s): Thaler, Michael H.
• Application Number:
  US06/874,814
• Time in Patent Office: 1,131 Days
• Field of Search: 128/303.1, 128/303.13, 128/303.14, 128/303.17, 128/303.11, 128/303.12, 128/399, 128/24.1, 30/140, 219/221, 219/227, 219/229, 219/230, 219/233, 219/235-240, 219/243, 228/51-55, 156/583
• US Class Current: 606/28
• CPC Class Codes: A61B 18/082 Probes or electrodes therefor
• CPC Class Codes: A61B 18/085 Forceps, scissors
• CPC Class Codes: A61B 2018/00107 Coatings on the energy applicator
• CPC Class Codes: A61B 2018/0097 Cleaning probe surfaces

Abstract

Method and means are disclosed for preventing tissue from adhering to surgical apparatus while operating at tissue temperatures at which hemostasis with minimal tissue damage occurs, and include interposing between the surgical apparatus and the tissue being heated thereby an abherent coating which exhibits electrical insulation and thermal impedance, thickness and thermal drop thereacross within specified limits.

Claims

1. A surgical apparatus for hemostatic cutting of tissue under surgical conditions comprising a scalpel blade, means for heating the blade to a preselected temperature in the range from about 100°

C. to about 500°

C. for causing hemostasis of cut tissue with minimal tissue damage, the means for heating selectively delivering heat to those areas of the blade selectively cooled by heat transfer from the blade to the tissue thereby maintaining the blade substantially at the preselected temperature, and an electrically insulating abherent coating on the scalpel blade for contactng the tissue to be cut, thermally conducting heat flux from the blade to the tissue, and reducing the accumulation of cut tissue on the apparatus so that the tissue to be cut may be cut and heated with a temperature drop across the abherent coating not substantially exceeding about 50°

C., the coating having an inner side in thermal contact with the blade or means for heating and an outer side for contacting tissue.

2. The apparatus of claim 1 wherein the abherent coating has a thermal impedence of less than 5°

C.-cm² /watt.

3. The apparatus of claim 1 wherein the abherent coating comprising a material selected from the group consisting of silicones, polydimethylsiloxanes, fluoride-metal composites and fluorocarbon polymers.

4. The apparatus of claim 1 wherein the abherent coating comprises a porous or scintered material having substantially continuous passageways therethrough and being impregnated with an abherent sacrificial material for reducing the accumulation of cut tissue on the apparatus.

5. The apparatus of claim 4 wherein the abherent sacrificial material is selected from the group consisting of silicone oils and ethers.

6. The apparatus of claim 1 wherein the thickness of the abherent coating is not greater than 0.5 mil.

7. The apparatus of claim 1 wherein the abherent coating is a solid.

8. A method for hemostatic cutting of tissue with minimal tissue damage under surgical conditions comprising:

providing a surgical apparatus comprising a scalpel blade having coated thereon an electrically insulating abherent coating;

heating the blade to a preselected substantially constant temperature in the range from about 100°

C. to about 500°

C., the temperature being selected for producing in the type of tissue being cut substantial hemostasis with minimal tissue damage;

cutting the tissue with the heated coated blade so that heat is transferred from the blade through the abherent coating to the tissue being cut;

selectively heating those areas of the blade that are cooled by transfer of heat from the blade to the tissue as the tissue is cut in order to maintain the scalpel substantially at the preselected temperature; and

providing the abherent coating with a thermal impedence so that the temperature drop across the abherent coating does not substantially exceed about 50°

C.

9. The method of claim 8 wherein the thermal impedence of the abherent coating is less than 5°

C.-cm² /watt.

10. The method of claim 8 wherein the abherent coating comprises a sacrificial abherent material that is exuded from the surgical apparatus.

11. The method of claim 10 wherein the sacrificial abherent material is selected from the group consisting of silicone oils and ethers.

12. The method of claim 8 wherein the thickness of the abherent coating is not greater than 0.5 mil.

13. The method of claim 8 wherein the abherent coating is a solid.

14. A surgical apparatus for causing hemostasis of tissue under surgical conditions comprising a scalpel blade, means for heating the scalpel blade to a preselected temperature in the range from about 100°

C. to about 500°

C. for causing hemostasis of tissue with minimal tissue damage, the means for heating selectively delivering heat to those areas of the scalpel blade selectively cooled by heat transfer from the scalpel blade to the tissue to maintain the scalpel blade substantially at the preselected temperature, wherein the surgical apparatus further comprises;

an electrically insulating abherent coating for contacting the tissue, thermally conducting heat flux from the scalpel blade to the tissue, and reducing the accumulation of tissue on the apparatus whereby the temperature drop across the abherent coating does not substantially exceed about 50°

C., the coating having an inner side in thermal contact with the scalpel blade or means for heating and an outer side for contacting tissue.

15. The apparatus of claim 14 wherein the abherent coating has a thermal impedence of less than 5°

C.-cm² /watt.

16. The apparatus of claim 15 wherein the thickness of the abherent coating is not greater than 0.5 mil.

17. The apparatus of claim 16 wherein the abherent coating is a solid.