Monitoring of the Electroencephalogram and Electromyogram During Anaesthesia

Abstract

Little attention has been paid to central nervous system monitoring of patients during general anesthesia. The lack of suitable instrumentation combined with the difficulty of electroencephalogram (EEG) interpretation has been among the discouraging factors. However, recent technological advances have made continuous quantitative EEG and electromyogram (EMG) recording possible during surgery. Bickford⁽¹⁾ pioneered in EEG monitoring during anaesthesia and since 1969 a highly simplified device, a brain function monitor has been used in several investigations⁽²⁾. Harmel, Klein and Davis⁽³⁾ introduced frontal muscle EMG activity recording as an index of relaxation and arousal caused by anaesthetic or surgical stimulation under general anaesthesia.