微血管减压术中异常肌反应监测的适宜神经肌肉阻滞程度

Appropriate degree of neuromuscular block for monitoring abnormal muscle response during microvascular decompression

目的:确定微血管减压术中异常肌反应(AMR)监测的适宜神经肌肉阻滞(NMB)程度。方法:选择术前诊断为面肌痉挛并拟行微血管减压术患者50例,性别不限,年龄20~64岁,体重指数≤30 kg/m^(2),ASA分级Ⅰ或Ⅱ级。静脉注射咪达唑仑0.05~0.10 mg/kg、舒芬太尼0.3~0.5μg/kg和丙泊酚1.5~2.5 mg/kg,待患者意识消失后行电生理监测,电刺激面神经颧支,在颏肌记录AMR的基础值;同时使用TOF-Watch SX肌松监测仪监测NMB程度,静脉注射罗库溴铵0.6 mg/kg后,在不同NMB程度(100%、75%、50%和25%)时测定AMR的振幅和潜伏期,计算振幅保留比率(实测AMR振幅与基础值的比值),分析振幅保留比率和潜伏期与NMB的关系。AMR监测中适宜NMB程度的判断标准:1.AMR振幅保留比率≥50%;2.电刺激面神经无任何体动反应。结果:在不同NMB程度进行电刺激面神经时,均无患者发生体动反应。振幅保留比率(Y)与NMB程度(X)呈负相关(r=-0.943,t=-42.73,P<0.001),回归方程为Y=90.36-0.8947 X,决定系数R2为0.8804(F=1825.41,P<0.001);潜伏期与外周NMB程度呈正相关(r=0.879,t=28.67,P<0.001),回归方程为Y=10.77+0.0743 X,决定系数R2为0.7681(F=821.30,P<0.001)。判断微血管减压术中AMR监测的适宜NMB程度为25%~45%。结论:微血管减压术中AMR监测的适宜NMB程度为25%~45%。

Objective To determine the appropriate degree of neuromuscular block(NMB)for abnormal muscle response(AMR)monitoring during microvascular decompression.Methods Fifty American Society of Anesthesiologists physical statusⅠorⅡpatients of both sexes,aged 20-64 yr,with body mass index≤30 kg/m^(2),who were diagnosed with facial spasm before surgery,scheduled for elective microvascular decompression,were selected.Anesthesia was induced with midazolam 0.05-0.10 mg/kg,sufentanil 0.3-0.5μg/kg and propofol 1.5-2.5 mg/kg.After patients lost consciousness,electrophysiological monitoring was performed,the zygomatic branch of the facial nerve was stimulated,and the baseline of AMR was recorded in the mental muscle.NMB was monitored with TOF-Watch SX monitor.After rocuronium 0.6 mg/kg was intravenously injected,the amplitude and latency of AMR were measured at different degrees of NMB(100%,75%,50%and 25%).The amplitude reservation ratio(the ratio of the amplitude of AMR monitored to the baseline value)was calculated.Linear correlation of the amplitude reservation ratio or latency of AMR with the degree of NMB was analyzed.The criteria for determining the appropriate degree of NMB in AMR monitoring were:1.amplitude reservation ratio of AMR≥50%;2.no body movement during electrical stimulatation of facial nerve.Results No patients had any body movement during electrical stimulation performed at different degrees of NMB.The amplitude reservation ratio(Y)was negatively correlated with the degree of NMB(X)(r=-0.943,t=-42.73,P<0.001),the linear regression equation of the interaction between the degree of NMB(X)and the amplitude reservation ratio(Y)was Y=90.36-0.8947X,and the coefficient of determination R2 was 0.8804(F=1825.41,P<0.001).The amplitude reservation ratio(Y)was positively correlated with the degree of NMB(X)(r=0.879,t=28.67,P<0.001)in the latency period,the linear regression equation of the interaction between the degree of NMB(X)and the latency(Y)was Y=10.77+0.0743X,and the coefficient of determination R2 was 0.7681(F=821.30,P<0.001).The estimated appropriate degree of NMB for AMR monitoring during microvascular decompression was 25%-45%.Conclusions The appropriate degree of NMB for AMR monitoring during microvascular decompression was 25%-45%.