Abstract
To compare accelography with electromyography (EMG) as a method of evaluating neuromuscular blockade on the hand and the foot, train-of-four (TOF) stimuli were simultaneously applied to the right ulnar nerve and bilateral tibial nerves. Two accelographs were applied to the right ulnar and the left tibial nerves. EMG was applied to the right tibial nerve. Twenty adult patients, aged 21 to 65 years, were studied. Anesthesia was induced with an intravenous injection of thiopental, and vecuronium 0.1mg•kg-1 was used for muscle relaxation. Anesthesia was maintained with nitrous oxide (66%)-oxygen and sevoflurane (1MAC). Times from initial administration of vecuronium to completion of maximal block were 136.5±25.7sec (the hand, accelograph), 180.8±32.5sec (the foot, accelograph) and 149.5±22.6sec (the foot, EMG), respectively. The maximal block of the foot (accelograph) was significantly longer than those of the hand (accelograph) and the foot (EMG). The times from maximal block to 25% recovery were 46.9±14.2min (the hand, accelograph), 36.1±8.9min (the foot, accelograph) and 47.4±8.9min (the foot, EMG), respectively. The result for the foot (accelograph) was significantly shorter than results for the hand (accelograph) and the foot (EMG). When the block was reversed at 25% of TOF ratio on the foot (accelograph), the TOF ratio on the hand (accelograph) and the foot (EMG) were 13.0±7.1% (P<.05) and 6.5±5.5% (P<0.01), respectively. We concluded from this study that accelography is more useful for assessing the degree of neuromuscular blockade than EMG and other methods after the administration of muscle relaxant. Head lifting, protruding of the tongue and sustaining a hand grip are also important in clinically evaluating the degree of blockade.
