咪唑安定对丙泊酚诱导需要量的影响

Effects of midazolam on induction dose requirements of propofol

目的 评估咪唑安定预先给药对减少丙泊酚需要量的影响。方法 ASAⅠ～Ⅱ择期手术病人 1 2 0例 ,随机分为丙泊酚组 (A组 )、咪唑安定 0 0 4mg/kg +丙泊酚组 (B组 )和咪唑安定 0 0 6mg/kg +丙泊酚组 (C组 ) ,按丙泊酚剂量每组又分为 4个亚组 :A组分为 0 75、1 1 3、1 6 8和 2 5mg/kg 4个亚组 ;B和C组均分为 0 33、0 5、0 75和 1 1 3mg/kg 4个亚组。A组直接静注丙泊酚 ,B和C组分别静注咪唑安定 0 0 4mg/kg或 0 0 6mg/kg ,6min后静注丙泊酚 ,速度均为1 5mg/s。静注丙泊酚或咪唑安定后 6min内每分钟进行OAA/S评分 ,并记录BIS。结果 (1 )OAA/S与BIS具有显著等级相关 (r =0 81 9,P <0 0 1 )。三次模型拟合曲线可表示OAA/S与BIS之间的关系 (r =0 6 83,P<0 0 1 )。 (2 )以OAA/S =0分为判断丙泊酚效应指标 ,A组丙泊酚的ED50 和ED95分别为 1 0 9mg/kg和 1 6 4mg/kg ;B组和C组分别使丙泊酚的ED50 下降 5 2 3%和 6 0 5 % ,ED95下降 4 7 6 %和5 1 8%。 (3)静注丙泊酚后 1～ 2min ,BIS下降到最低值。与A组相比 ,B和C组使BIS降至相应值的丙泊酚需要量明显减少 ,同时BIS维持低水平的时间显著延长。结论 预先静注咪唑安定 0 0 4mg/kg可显著减少丙泊酚用量 。

Objective To evaluate the effects of midazolam on induction dose requirements of propofol.Methods One hundred and twenty patients,ASA Ⅰ Ⅱ,were randomly divided into three groups,and each group was further divided to four subgroups according to the dose of propofol used.Group A received propofol alone in the dose of 0 75 mg/kg,1 13 mg/kg,1 68 mg/kg and 2 5 mg/kg respectively,and group B and C were pretreated with midazolam of 0 04 mg/kg and 0 06 mg/kg 6 min before to propofol injection in the doses of 0 33 mg/kg,0 5 mg/kg,0 75 mg/kg and 1 13 mg/kg respectively. Bolus propofol was intravenously administrated to all patients at a rate of 15 mg/s,then the observer's assessment of alertness/ sedation scale (OAA/S) was evaluated and bispectral index (BIS) was recorded in every minute.Results (1) OAA/S had a high positive spearmans correlation to BIS ( r= 0 819, P< 0 01).Cubic curve estimation was adapt to describe the relationship between OAA/S and BIS ( r= 0 683, P< 0 01).(2) The ED 50 and ED 95 of propofol at OAA/S=0 in group A were 1 09 mg/kg and 1 64 mg/kg respectively.Pretreatment with midazolam of 0 04 mg/kg and 0 06 mg/kg significantly lowered the ED 50 and ED 95 by 52 3%, 60 5% and 47 6%,51 8%,respectively.(3) BIS in three groups decreased to its lowest values in 1 2 minutes after intravenous propofol.Compared to group A,group B and C significantly decreased the dose requirement of propofol to make the corresponding BIS values lowered,and the time of lower BIS prolonged .Conclusion Pretreatment with midazolam significantly decreases the dose requirement of propofol and prolonges the duriation of action of propofol.