Saitoh Y, Fujii Y, Makita K, Tanaka H, Amaha K
Department of Anesthesiology and Critical Care Medicine, Tokyo Medical and Dental University, Japan.
Acta Anaesthesiol Scand. 1998 Aug;42(7):851-7. doi: 10.1111/j.1399-6576.1998.tb05333.x.
Using modified double burst stimulation (modified DBS), sufficient level of recovery from neuromuscular blockade (train-of-four (TOF) ratio > 0.7) can properly be diagnosed. Modified DBS may often be applied in awake patients in the postanesthetic care unit. As the stimulating current decreases, the neurostimulation-induced discomfort becomes less for awake subjects. It is relevant to investigate the usefulness of the modified DBS delivered at low currents.
One hundred and twenty-one adult patients undergoing nitrous oxide-oxygen-isoflurane anesthesia were randomly divided into one of four groups: group 50 (n = 40), group 30 (n = 40), group 20 (n = 40), and supramaximality group (n = 1). After administration of vecuronium, in one hand and forearm (fixed arm), the degree of neuromuscular blockade was quantified mechanically. In the contralateral arm (free arm), modified DBS stimuli were delivered at 50, 30, and 20 mA in groups 50, 30, and 20, respectively. An observer determined tactilely on the free arm the presence or absence of fade in response to the modified DBS applied at 50, 30, and 20 mA. In one patient (the supramaximality group), modified DBS ratios (D2/D1) were examined at 50, 40, 30, 20, and 10 mA before administration of vecuronium. Moreover, discomfort associated with modified DBS applied at 50, 30, and 20 mA was evaluated using a 10-cm visual analog scale (VAS) in 15 awake volunteers.
Probabilities of detection of fade in response to modified DBS in groups 50, 30, and 20 were 90, 86, and 96% (TOF ratios of 0.61-0.70), 62, 73, 94*#% (0.71-0.80), 26, 39, and 79*#% (0.81-0.90), and 4, 33*, and 51*#% (0.91-1.00), respectively. P < 0.05 as compared to group 50. #P < 0.05 as compared to group 30. Supramaximal responses to D1 and D2 could be elicited at a current > or = 30 mA. The mean VAS scores were 8.7, 6.5, and 4.1* when stimulated at 50, 30, and 20 mA, respectively. *P < 0.05 as compared to 50 mA. #P < 0.05 as compared to 30 mA.
Modified DBS-induced discomfort becomes less as the stimulating current decreases. However, when stimulated at 30 or 20 mA, fade in response to modified DBS is felt in too many cases, even after neuromuscular blockage subsides to an adequate level.
使用改良双爆发刺激（modified DBS），可以准确诊断出从神经肌肉阻滞中充分恢复的水平（四个成串刺激（TOF）比值>0.7）。改良DBS通常可应用于麻醉后护理单元中的清醒患者。随着刺激电流降低，神经刺激引起的不适对于清醒受试者会减轻。研究低电流下改良DBS的有效性具有重要意义。
121例接受氧化亚氮-氧气-异氟烷麻醉的成年患者被随机分为四组之一：50mA组（n = 40）、30mA组（n = 40）、20mA组（n = 40）和超强刺激组（n = 1）。给予维库溴铵后，在一只手和前臂（固定臂），通过机械方法对神经肌肉阻滞程度进行量化。在对侧手臂（自由臂），50mA组、30mA组和20mA组分别以50、30和20mA给予改良DBS刺激。一名观察者通过触觉判断自由臂对50、30和20mA改良DBS刺激是否存在衰减。在一名患者（超强刺激组）中，在给予维库溴铵前，分别以50、40、30、20和10mA检查改良DBS比值（D2/D1）。此外，使用10厘米视觉模拟量表（VAS）对15名清醒志愿者中50、30和20mA改良DBS刺激相关的不适进行评估。
50mA组、30mA组和20mA组对改良DBS刺激出现衰减的检测概率分别为90%、86%和96%（TOF比值为0.61 - 0.70），62%、73%和94*#%（0.71 - 0.80），26%、39%和79*#%（0.81 - 0.90），以及4%、33*%和51*#%（0.91 - 1.00）。与50mA组相比，P < 0.05。#与30mA组相比，P < 0.05。在电流≥30mA时可引发对D1和D2的超强反应。分别在50、30和20mA刺激时，平均VAS评分分别为8.7、6.5和4.1*。*与50mA相比，P < 0.05。#与30mA相比，P < 0.05。
随着刺激电流降低，改良DBS引起的不适减轻。然而，当以30或20mA刺激时，即使神经肌肉阻滞消退至适当水平，仍有太多情况下会感觉到对改良DBS刺激的衰减。
