右美托咪定对平稳拔除气管导管时七氟烷半数有效浓度的影响

Effects of Dexmedetomidine on Sevoflurane Median Effective Concentration during Extubation

目的观察术中应用右美托咪定对全麻患者术后平稳拔除气管导管时七氟烷半数有效浓度(EC50),以及患者苏醒质量的影响,探讨右美托咪定改善全麻苏醒质量的可行性.方法将60例患者随机分为两组(n=30).右美托咪定组:诱导后静脉泵注右美托咪定1μg/kg.对照组:诱导后输注同等量的生理盐水.常规给予麻醉诱导及维持,手术结束时根据Dixon序贯法确定拔除气管导管的七氟烷浓度,并观察患者拔管时间、睁眼时间、Ramsay评分达3分、1分时间以及并发症情况.结果 2组患者的一般资料相比无统计学差异(P>0.05).右美托咪定组和对照组患者拔除气管导管时七氟烷半数有效浓度(EC50)分别是0.22MAC和0.61MAC,其95%的可信区间分别为(0.14~0.30)MAC和(0.47~0.75)MAC,2组相比差异有统计学意义(P<0.01).右美托咪定组和对照组患者在全麻苏醒时的气管导管拔管时间、睁眼时间、Ramsay评分达3分、1分时间相比,2组均无统计学意义(P>0.05);2组出现并发症的例数相比具差异有统计学意义(P<0.05).结论围术期应用右美托咪定可降低平稳拔除气管导管所需七氟烷的半数有效浓度(EC50),对患者苏醒时间无明显影响,但减少了拔管后七氟烷所致呼吸抑制的发生率,改善了苏醒质量.

Objective To investigate the effects on sevoflurane median effective concentration （EC50） of intraoperative dexmedetomidine during postoperative extubation and the effects of awaking quality, to explore the feasibility of dexmedetomidine and to improve the quality of recovery from general anesthesia. Methods 60 patients were randomly divided into two groups （n=30） . Dexmedetomidine group： 1 μg/kg intravenous infusion of dexmedetomidine after induction. Control group ： the same amount of normal saline injection after induction. At the end of the operation, sevoflurane concentrations of tracheal extubation was determined according to the Dixon sequential method, while extubating time, waking time, the time of Ramsay score of 3 points and 1 point and complications were observed. Results There was no significant difference in general data between the two groups （P〉0.05） . Sevoflurane ECs0 of dexmedetomidine group and control group were 0.22 MAC and 0.61 MAC, the 95% confidence interval was （0.14 - 0.30） MAC and MAC （0.47 - 0.75）, and there were significant differences between the two groups （P〈O.01） . There was no significant difference in extubating time, waking time, the time of Ramsay score of 3 points, 1 point between the two groups （P〉0.05） . There were statistically significant differences in the number of complications between the two groups （P 〈0.05） . Conclusions Apolication ofdexmedetomidine can reduce the sevoflurane EC50 during extubation without side effect on the recovery time of patients, decrease the incidence of respiratory depression after extubation, and improve the recovery quality.