不同剂量右美托咪定对丙泊酚诱导效应室靶浓度的影响

Effects of different doses of dexmedetomidine on effect-site concentration of propofol during intubation of general anesthesia induction

目的观察不同剂量右美托咪定在全麻患者气管插管时有效性和安全性及对丙泊酚效应室靶浓度(Ce)的影响。方法 60例全麻下行择期上腹部手术患者,随机均分为四组:D1、D2、D3、C组,分别在麻醉诱导前10min静脉泵注右美托咪定0.25μg/kg(D1组)、0.5μg/kg(D2组)和1.0μg/kg(D3组)及10ml生理盐水(C组)。麻醉诱导采用靶控输注丙泊酚,以BIS为靶控目标。丙泊酚初始Ce设为1.5μg/ml,递增梯度为0.5μg/ml,同时泵注瑞芬太尼0.2μg·kg-1·min-1。BIS≤60时推注罗库溴铵0.9mg/kg,BIS≤50并维持5s行气管插管。于输注右美托咪定前(T0)、诱导前(T1)、气管插管前(T2)、气管插管后1min(T3)、3min(T4)、5min(T5)、10min(T6)时记录SBP、DBP、HR、BIS、丙泊酚Ce。结果与T0时比较,T1时D2、D3组HR减慢、D3组SBP、DBP升高(P<0.05);与T1时比较,T2时D1组和C组SBP、DBP下降,HR减慢(P<0.05);与T2时比较,T3～T5时D1组和C组SBP、DBP升高,HR增快,T3时C组BIS升高(P<0.05)。T2～T6时丙泊酚CeD1、D2、D3组明显低于C组(P<0.05)。不同剂量右美托咪定各时点对丙泊酚Ce存在明显负相关关系。结论麻醉诱导前静脉输注不同剂量右美托咪定对丙泊酚诱导效应室浓度存在负相关关系。麻醉诱导前静脉输注右美托咪定0.5μg/kg心血管反应平稳并能显著减少诱导时所需丙泊酚Ce。

Objective To investigate the effects of different doses of dexmedetomidinthe in patients safety and availability during intubation of general anesthesia induction effect-site concentration （Ce） of propofol. Methods Sixty patients undergoing elective upper abdominal surgery under general anesthesia were randomly divided into 4 groups, 15 cases each. Patients in the group D1, group 192, group D3 and group C were respectively administered with dexmedetomidine 0. 25, 0.5, 1.0 mg/kg, or sodium chloride injection by micro pump in 10 minutes before anesthesia induction. After infusion, anesthesia was induced with target-controlled infusion （TCI） of propofol, the initial Ce of propofol was set 1.5 mg/ml, according to bispectral index （BIS） increased 0.5μg/ml every one minute, remifentanil was infused at 0.2 mg·kg^-1 · min^-1. Rocuronium 0. 9 mg/kg were injected and tracheal were intubated when BIS 460 and BIS 450 maintained 5 s, respectively. SBP, DBP, HR, BIS, and propofol Ce were recorded at the time before dexmedetomidine infusion （T0）, before induction （T1）, just before tracheal intubation （T2） and 1,3, 5, 10 minutes （T3-T6） after intubatioru Results Compared with To, HR in groups D2 and D3 were decreased and SBP and DBP in group D3 were increased at T1 （P〈0.05）. Compared with T1, there were decreased for SBP,DBP and HR in group C and group D1 at T2. Compared with T2, SBP, DBP and HR in group C and group D1 were higher than those at T3 Ts. BIS at T3 was elevated in group C （P〈0.05）. The propofol Ce of group DI, D2 and D3 were lower than in group C at T2-T6 （P〈0.05）. In addition, there was a negative correlation that different dose at different time points of propofol Ce. Conclusion There is a negative correlation that intravenous infusion different dose dexmedetomidine before given propofol Ce induction of anesthesia. Intravenous infusion 0. 5mg/kg dexmedetomidine, the concentration of propofol can significantly decrease and cardiovascular response may steady.