Electrically heated surgical blade and methods of making

United States Patent [19]

Eggers et al.

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US005308311A

[ii] Patent Number: 5,308,311 [453 Date of Patent: May 3, 1994

[54] ELECTRICALLY HEATED SURGICAL BLADE AND METHODS OF MAKING

[75] Inventors: Philip E. Eggers, Dublin, Ohio;

Robert F. Shaw, 1750 Taylor St., San
Francisco, Calif. 94108

[73] Assignee: Robert F. Shaw, San Francisco, Calif.

[21] Appl. No.: 877,698

[22] Filed: May 1, 1992

[51] Int. CI.* A61B 17/38

[52] U.S. CI 606/28; 606/31;

606/45; 606/29

[58] Field of Search 606/27, 28, 29, 30,

606/31, 32, 34, 37, 38, 39, 40, 41, 42, 45, 49

[56] References Cited

U.S. PATENT DOCUMENTS

Re. 31.723 11/1984 Shaw 606/31

3.768,482 10/1973 Shaw 128/303.1

3.826.263 7/1974 Cage et al 128/303.1

4.161.950 7/1979 Doss et al 128/303.14

4,231.371 11/1980 Lipp 606/31

4.314.559 2/1982 Allen 606/45

4.364.390 12/1982 Shaw 606/29

4.481.057 11/1984 Beard 156/216

4.485.810 12/1984 Beard 128/303.1

4.754.754 7/1988 Garito et al 128/303.14

4.770.067 9/1988 Liu et al 76/104 R

4.785.807 11/1988 Blanch 128/303.14

4.802.476 2/1989 Noerenberg et al 128/303.14

4.848.337 7/1989 Shaw et al 606/28

4.850,353 7/1989 Stasz et al 128/303.14

4,862,890 9/1989 Stasz et al 128/303.14

4,958,539 9/1990 Stasz et al 76/104.1

Primary Examiner—Peter A. Aschenbrenner
Attorney, Agent, or Firm—Nicola A. Pisano

[57] ABSTRACT

A hemostatic surgical blade and methods of manufacturing such blades are provided, wherein the blade comprises a laminate region having a hardenable center layer and highly thermally conductive outer layers, joined to a second region of a low thermal conductivity material. A heating element is secured to the laminate region and in thermal communication therewith to thermally reform the collagen of tissue as it is incised. The heat generated by the heating element is conducted to the cutting edge of the blade to maintain the cutting edge temperature within 20° C. to 70° C. of a userselected operating temperature. The second region reduces the conduction of heat to the handle of the instrument. The heating element comprises a thermally conductive dielectric layer attached to an outer surface of the laminate region, resistive conductive elements deposited on the dielectric, a second dielectric layer covering the resistive conductor elements, and an abherent coating disposed thereon to reduce coagulum buildup on the blade.

29 Claims, 4 Drawing Sheets