Turner G A, Williams J D, Baker D J
Department of Anaesthetics, Royal Naval Hospital, Haslar, Gosport Hampshire.
Br J Anaesth. 1989 Mar;62(3):279-86. doi: 10.1093/bja/62.3.279.
The actions of alcuronium, vecuronium and tubocurarine have been studied in the isolated forearms of six healthy, non-anaesthetized volunteers. The responses of adductor pollicis were measured during onset and recovery of neuromuscular block for each agent. There was a drug-related disparity between mechanomyogram (MMG) and electromyogram (EMG) measurement of the first response of the train-of-four (T1) and of the ratio of the fourth (T4) to the first response (TOF ratio). There were significantly higher T1 values for the EMG than for MMG during alcuronium blockade (P = 0.03). For tubocurarine, however, the relationship was reversed. The relationship between T1 and TOF ratio during onset and recovery of neuromuscular block was a hysteresis. The TOF ratio at 50% T1 was significantly higher during onset than during recovery for all three drugs, measured by MMG or EMG (P less than 0.005). Analysis of variance of the differential fade loops failed to show a drug-related effect. We conclude that care should be taken in assuming interchangeability between MMG and EMG measurement of T1. Relationships between T1 and TOF ratio derived during recovery do not necessarily apply during onset and may lead to error in estimating the degree of muscle relaxation.
已在6名健康、未麻醉的志愿者的离体前臂中研究了阿库氯铵、维库溴铵和筒箭毒碱的作用。在每种药物引起的神经肌肉阻滞起效和恢复过程中，测量拇内收肌的反应。在四个成串刺激（T1）的首次反应以及第四个反应（T4）与第一个反应的比值（强直刺激比值，TOF比值）的机械肌电图（MMG）和肌电图（EMG）测量之间，存在与药物相关的差异。在阿库氯铵阻滞期间，EMG的T1值显著高于MMG（P = 0.03）。然而，对于筒箭毒碱，这种关系则相反。神经肌肉阻滞起效和恢复过程中T1与TOF比值之间的关系呈滞后现象。通过MMG或EMG测量，所有三种药物在T1为50%时的TOF比值在起效期间显著高于恢复期间（P < 0.005）。对差异衰减环的方差分析未显示出与药物相关的效应。我们得出结论，在假设MMG和EMG对T1的测量具有互换性时应谨慎。恢复过程中得出的T1与TOF比值之间的关系不一定适用于起效期间，可能会导致在估计肌肉松弛程度时出现误差。
