Comparison of acceleromyography and electromyography in vecuronium-induced neuromuscular blockade with xenon or sevoflurane anesthesia.

Study Objectives: To compare acceleromyography (AMG) and electromyography (EMG) with xenon or sevoflurane anesthesia during vecuronium-induced neuromuscular blockade.

Design: Prospective randomized study.

Setting: University hospital.

Patients: 28 ASA physical status I and II adult patients presenting for elective surgery.

Interventions: Patients received vecuronium for neuromuscular blockade and either xenon (n = 11) or sevoflurane (n = 17) anesthesia.

Measurements And Main Results: The first twitch depression, which was expressed as a ratio of the first twitch to that obtained before the blocking drug was administered (T1/Tc), was measured simultaneously by AMG and EMG. T1/Tc as measured by AMG consistently demonstrated greater depression than that by EMG during recovery. The limits of agreement were unacceptably wide, suggesting that T1/Tc obtained by AMG is a poor predictor of T1/Tc as measured by EMG. Such relations were not affected by the anesthetic (xenon or sevoflurane) used.

Conclusion: AMG and EMG-cannot be used interchangeably with either xenon or sevoflurane anesthesia.