部分肌松条件下术中面神经运动诱发电位监护的临床应用

Clinical study on intraoperative facial nerve motor evoked potentials monitoring under partial neuromuscular blockade

目的 测定术中面神经运动诱发电位（FNMEP）监护的最佳肌松程度,并探讨听神经瘤切除术中部分肌松下进行FNMEP监护的可行性.方法 本研究的第一部分通过记录30例患者在不同肌松程度下获得眼轮匝肌和口轮匝肌的波幅和潜伏期以及患者的经颅电刺激诱发的体动反应来确定最佳的肌松程度;第二部分对15例择期行听神经瘤切除术的患者在最佳肌松程度下进行术中FNMEP监护,并分析其预测术后面神经功能的敏感性和特异性.结果 在单颤搐刺激肌松监测模式下,当T1=30%～40%时,既可记录到清晰可辨的FNMEP的波形,体动的影响也最小.在此肌松程度下,15例听神经瘤切除术均成功进行了术中FNMEP的监护.而术后/术前FNMEP波幅比值预测术后神经功能的敏感度和特异度分别达到了90%和91%.结论 单次肌颤搐刺激下T1=30%～40%是适用于术中FNMEP监护的肌松程度.在此肌松程度下进行术中监护同样能够及时发现听神经瘤切除术中的面神经损伤.

Objective To find optimal partial neuromuscular blockade used for intraoperative facial nerve motor evoked potential （FNMEP） monitoring and its feasibility for application in patients undergoing acoustic neuroma resection.Methods Two parties were included： the amplitude and latency of FNMEP and electrical stimulation-induced body movement scores were recorded under various degree of neuromuscular blockade in thirty neurosurgical patients.After the optimal partial neuromuscular blockade was obtained,intraoperative FNMEP monitoring was performed in fifteen patients undergoing acoustic neuroma resection .The sensitivity and specificity of FNMEP were analyzed according to postoperative/preoperative amplitude of FNMEP and postoperative facial nerve function.Results The FNMEP waveforms were discernible and less electrical stimulation induced body movement was observed when T1 =30%～40% was used.Fifteen patients were monitored successfully with FNMEP.And the sensitivity and specificity of postoperative/preoperative FNMEP amplitude ratio to predict postoperative facial nerve function were 90% and 91% respectively.Conclusions T1=30%～40% is optimal partial neuromuscular blockade used for intraoperative FNMEP monitoring and FNMEP monitoring under such partial neuromuscular block is feasible and reliable.