An evoked compound electromyogram simulator with external microprocessor control facility

A circuit for an evoked electromyogram simulator is described, which produces a biphasic triangular waveform similar to the evoked compound action potential seen during clinical quantitative neuromuscular monitoring. The device can produce a fading train-of-four sequence, which can be controlled using a single externally-derived voltage. The simulator is useful for bench-testing of closed loop muscle relaxant administration systems, and for teaching aspects of neuromuscular monitoring in anaesthesia.