Three-part neutral electrode for a high frequency surgery device

US5000753A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Uwe Hagen · Forchheim, DE
• Peter Feucht · Teltow, DE

Key dates

• Filing date: Jan 30, 1990
• Grant date: Mar 19, 1991
• Expiry date: Jan 30, 2010

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61B5/276
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A neutral electrode for a high frequency surgery device has three planar sub-electrodes, which are arranged side by side on a carrier consisting of insulating material. To improve monitoring of the contact of the sub-electrodes with the body of the patient, the two outer sub-electrodes have substantially triangular contact surfaces, with the respective hypotenuses of the triangular contact surfaces proceeding parallel to and spaced from each other, with a central, strip-shaped sub-electrode disposed between the hypotenuses of the outer sub-electrodes. The neutral electrode is intended for use with a monitoring system which will activate an alarm if the neutral electrode becomes detached from the patient to such an extent that the danger of injury to the patient exists. This is accomplished by monitoring a current or currents flowing through the patient between sub-electrodes. The neutral electrode does not have an axis of symmetry along which a detachment of the neutral electrode from the patient could occur which would fail to cause a sufficient impedance change to trigger the alarm in time to avoid injury to the patient.