Abstract:

 Objective To observe the effect of dexmedetomidine on reducing the myoclonus rates caused by etomidate for patients with thyroid surgery anesthesia awakening period. Methods Sixty patients with thyroid surgery（ASA I to II, 20 to 44 years old）were divided into the observation group（n= 30）and the control group（n=30）. The patients in two groups were treated with intravenous midazolam （0.03 mg · kg- 1）, fentanyl（0.003 mg · kg- 1）, etomidate（0.3 mg · kg- 1）for general anesthesia induction intubation, and both were followed by continuous infusion of etomidate（8 μg/kg- 1 · min- 1）and remifent-anil（0.2 μg · kg-1 · min-1）for maintaining anesthesia. On this basis, the observation group were given in-travenous infusion of dexmedetomidine（4 μg · kg- 1 · h- 1, 4 μg · ml- 1）, while the control group was given the same dose of normal saline（1 ml · kg- 1 · h- 1）. The temperature before induction（T1）, after tracheal intubation（T2）, the end of operation（T3）, awake after extubation（T4）, heart rate（HR）, mean arte-rial pressure（MAP）and the occurrence of myoclonus after recovery and the severity of myoclonus were recorded. The intraoperative additional amount of sevoflurane, intraoperative and postoperative adverse reactions were also recorded. Results There were significant differences between HR and MAP T2- T4 at each time point in the two groups（all P values < 0.05）；the incidence of restlessness and postopera-tive shivering in the observation group after surgery was significantly lower than the control group （P=0.046 and 0.023）. There were 2 and 9 patients who suffered from myoclonus occurring in the induced pe-riod in the observation and control group, respectively（P=0.021）, and 2 and 8 in the recovery period, respectively（P=0.039）. About the severity of comparison, 2 cases in observation group were 1 and 2, no grade 3, while the control group was treated mainly with 3 and 2 grade myoclonus. The total numberof cases and clonus grade in two group composition were statistically significant （P=0.003）. Moreover, the recovery time, extubation time and the recovery time of the directional force in the observation group were significantly shorter than those in the control group（all P<0.05）. Conclusion Dexmedetomidine can effectively reducing the myoclonus rates caused by etomidate for patients with thyroid surgery anes-thesia awakening period, maintain hemodynamic stability, shorten the recovery time, extubation, direc-tional force recovery time and reduce the adverse reactions.

Key words: myoclonus, thyroid surgery, dexmedetomidine, general anesthesia, etomidate

摘要：

目的 观察右美托咪定对抗依托咪酯致甲状腺手术全麻苏醒期患者肌阵挛的效果评价。方法 选择择期甲状腺手术患者60例，ASAⅠ~Ⅱ级，年龄20~44岁，分为观察组及对照组各30例，两组均采用静脉注射咪达唑仑0.03mg·kg-1、芬太尼0.003mg·kg-1、依托咪酯0.3mg·kg-1全麻诱导插管，随后持续泵注依托咪酯8μg·kg-1min-1和瑞芬太尼0.2μg·kg-1min-1作麻醉维持；观察组在此基础上给予分别静注右美托咪定4μg·kg-1·h-（14μg·mL-1），而对照组给予等量（1mL/kg·h）生理盐水；记录诱导前（T1）、气管插管后（T2）、手术完毕（T3）、清醒拔管后（T4）的体温、心率（HR）、平均动脉压（MAP）以及苏醒后肌阵挛的发生情况，并记录肌阵挛的严重程度；记录术中追加七氟醚用量以及术中和术后不良反应发生情况。结果 T2~T4各时点两组的HR与MAP的差异有统计学意义（所有P<0.05）；观察组患者术后躁动及术后寒颤的发生率显著低于对照组（P=0.046及0.023）；观察组分别有2例在诱导期及苏醒期出现肌阵挛，而对照组为9例及8例，两组例数构成有统计学差异（P=0.021及0.039））；在程度的比较方面，观察组苏醒期出现肌阵挛的2例分别为1及2级，无3级阵挛；而对照组以3及2级阵挛为主，两组构成均有统计学差异（P=0.003），但两组肌阵挛所致的严重并发症无统计学差异（P=0.154）。观察组的苏醒时间、拔管时间、定向力恢复时间较对照组有明显的缩短（所有P<0.05）。结论 右美托咪定能有效对抗依托咪酯致甲状腺手术全麻苏醒期肌阵挛的发生，维持血流动力学稳定，可缩短苏醒、拔管、定向力恢复时间，并减少不良反应发生。

关键词: 右美托咪定, 肌阵挛, 甲状腺手术, 全身麻醉, 依托咪酯