颈丛麻醉下甲状腺手术中喉返神经的功能监测

目的 探讨在颈丛麻醉下,通过针电极记录环杓侧肌复合肌肉动作电位(CMAP)对甲状腺手术中喉返神经功能进行监测的可行性.方法 使用美国尼高力Endeavor CR术中神经功能监测仪,通过针电极记录环杓侧肌CMAP,同心圆电极间断性刺激暴露或未暴露的喉返神经,对颈丛麻醉下甲状腺手术中喉返神经功能进行监测.结果 28例患者术中暴露31条喉返神经,刺激后均出现潜伏期恒定的CMAP;所需要的刺激强度为0.2～1.6mA,平均为0.96mA;而沿着同一神经未暴露段的可能行径进行刺激时,其中25条神经出现稳定的复合肌肉动作电位,刺激强度1.3～3.5 mA,平均为2.03 mA,其余6条神经即使刺激强度达5 mA未能诱发出CMAP,但该6例神经完全解剖暴露后,仍可出现稳定的环杓侧肌诱发肌电图.28例患者术后发音全部正常.结论 通过环杓侧肌记录CMAP对颈丛麻醉下甲状腺术中的喉返神经功能进行监测,是一项安全、有效、可行的方法.

Intraoperative recurrent laryngeal nerve monitoring during thyroid surgery under block anaesthesia of the cervical plexus

Objective To investigate the monitoring of the recurrent laryngeal nerve (RLN)function during thyroid surgery by recording the compound muscle action potential (CMAP) of lateral cricoarytenoid muscle(LCA) under block anaesthesia of the cervical plexus. Methods Nicolet Endeavor CR(Viasys Healthcare, USA) was applied for the intraoperative monitoring. A pair of needle electrodes were inserted into LCA to record CMAP, and a concentric electrode was used to intermittently stimulate the RLN for monitoring the RLN function during operation under block anaesthesia of the cervical plexus.Results In these 28 cases 31 RLNs were exposed during operation, CMAPs appeared with consistent latency when stimulation was applied at the exposed segment. The stimulating intensity threshold ranged from 0.2 to 1.6 mA. The average value was 0.96 mA. 25 of 31 showed CMAPs with consistent latency when stimulation was provided along the possible pathway of the unexposed segment. The stimulating intensity threshold ranged from 1.3 to 3.5 mA. The average value was 2. 03 mA. 6 of 31 did not evoked CMAP even though the maximal stimulating intensity was 5 mA. When these six nerves were exposured, compound muscle action potential were evoked consistently. All of the 28 patients had normal phonation function after surgery.Conclusions It is a safe, effective and feasible method to monitor the RL N function by recording the CMAP of lateral cricoarytenoid muscle under block anaesthesia of the cervical plexus.