Govindarajan Ramasamy, Shah Ajay, Ravikumar Saiganesh, Reddy Sunil K, Kannan Umashankkar, Mukerji Amar N, Cherian Jasmine G, Foster Crista, Livingstone Dave
Division of North American Partners in Anesthesia, Department of Anesthesia, BronxCare Health System, 1650 Grand Concourse, Bronx, NY 10457, USA.
Department of Surgery, BronxCare Health System, 1650 Grand Concourse, Bronx, NY 10457, USA.
J Clin Med Res. 2021 Apr;13(4):214-221. doi: 10.14740/jocmr4458. Epub 2021 Apr 27.
Intraoperative nerve monitoring (IONM) to assess the recurrent laryngeal nerve function during thyroid surgery is becoming the standard of care across many institutions. The successful deployment and data analysis from the IONM require complete laryngeal relaxation and reflex suppression. We investigated the role of intravenous lidocaine infusion (IVLI) to provide such operating conditions, under a lighter plane of anesthesia and fewer hemodynamic fluctuations.
Sixty-five patients were randomly assigned to lidocaine group (LG) or placebo group (PG) based on the computer-generated coding developed by the pharmacy department. The study medication (SM) was delivered by the pharmacist in a pre-filled coded syringe to the investigator 30 min prior to the surgery. All the patients were anesthetized by narcotic and inhalation based general anesthesia. The SM was administered at the rate of 1.5mg/kg/h following a loading dose of 1 mg/kg. Dragonfly laryngeal surface electrode and Nerveana nerve locator system were used for IONM during surgery.
The proportion of patients requiring lower strength stimulating current (StMC) at 0.5 mA was significantly higher in the LG than in the PG (X (1, N = 61) = 10.1615, P = 0.001434). Similarly, the proportion of patients with the drop in the aggregate impedance level (DAIL) by < 50% at the end of surgery was significantly higher in the LG than in the PG (X (1, N = 61) = 15.982, P = 0.000064). In addition, the proportion of patients with the hypotensive episodes requiring rescue medications more than twice during surgery was significantly lower in the LG than in the PG (X (1, N = 61) = 0.0183, P < 0.05).
The enhanced laryngeal relaxation and the reflex suppression afforded by the IVLI could have enabled a lower StMC to elicit a positive signal. The lower StMC promotes less intense laryngeal alterations as evidenced by the lower DAIL in the LG. IVLI can enhance the functionality of the IONM during prolonged operating time and the resultant increased number of IONM stimulations, while providing a stable hemodynamic environment.
术中神经监测（IONM）用于评估甲状腺手术期间喉返神经功能，正成为许多机构的护理标准。IONM的成功部署和数据分析需要完全的喉部松弛和反射抑制。我们研究了静脉输注利多卡因（IVLI）在较浅麻醉平面和较少血流动力学波动情况下提供此类手术条件的作用。
根据药房制定的计算机生成编码，将65例患者随机分为利多卡因组（LG）或安慰剂组（PG）。研究药物（SM）由药剂师在手术前30分钟通过预先填充编码的注射器提供给研究者。所有患者均采用基于麻醉剂和吸入的全身麻醉。在给予1mg/kg负荷剂量后，以1.5mg/kg/h的速率给予SM。术中使用蜻蜓喉表面电极和Nerveana神经定位系统进行IONM。
LG组中在0.5mA时需要较低强度刺激电流（StMC）的患者比例显著高于PG组（X（1，N = 61）= 10.1615，P = 0.001434）。同样，手术结束时总阻抗水平下降（DAIL）< 50%的患者比例在LG组中显著高于PG组（X（1，N = 61）= 15.982，P = 0.000064）。此外，术中需要抢救药物超过两次的低血压发作患者比例在LG组中显著低于PG组（X（1，N = 61）= 0.0183，P < 0.05）。
IVLI提供的增强喉部松弛和反射抑制可能使较低的StMC就能引出阳性信号。较低的StMC导致喉部改变较轻，如LG组中较低的DAIL所示。IVLI可在延长的手术时间和由此增加的IONM刺激次数期间增强IONM的功能，同时提供稳定的血流动力学环境。
