Electromyography in anaesthesia A comparison between two methods

Abstract

Two instruments measuring evoked compound muscle action potentials (EMG) produced by train of four stimulation of the ulnar nerve were compared. The neuromuscular transmission section of a Datex Anaesthesia and Brain Monitor (ABM), which utilises an integration technique to measure the EMG, and the Medelec MS6 , by which amplitude of the EMG was recorded and measured were attached to the same electrodes placed over adductor pollicis. Eight patients scheduled for surgery requiring non-depolarising neuromuscular blockade were studied. The changes in neuromuscular transmission measured by the two methods correlated well, with no statistically significant difference in results. The ABM provides a simple and accurate automatic measurement of evoked EMG for use in the study of neuromuscular transmission.