Patent ID: 8187263
Filing Date: 2012-05-29
Classification: A61B

Abstract:
1. A return electrode monitoring system comprising: at least one return electrode including at least one pair of split electrode pads; a detection circuit operatively coupled to the at least one pair of split electrode pads, wherein the detection circuit and the at least one pair of split electrode pads are adapted to resonate across a predetermined resonance; and a controller coupled to the detection circuit and configured to provide a sweeping drive signal to the detection circuit across a resonance range of the predetermined resonance, the detection circuit configured to measure a voltage and a current of a response drive signal and a phase difference therebetween, wherein the controller determines a complex impedance across the at least one pair of split electrode pads as a function of the response drive signal and is configured to determine a phase of the response drive signal with respect to a frequency of the sweeping drive signal and a frequency shift as a function of the phase of the response drive signal.