Half Effective-site Concentration Of Remifentanil Inhibiting Cardiovascular Response To Tracheal Intubation And Skin Incision Combined With Propofol In Patients Of Uygur Nationality

Objective: To determine the half-effective effect-site concentration ofremifentanil(ECe50) inhibiting cardiovascular response to tracheal intubation and skinincision combined with propofol in patients of Uygur nationality. Methods: Thirty ASAⅠorⅡ Uighurs aged20-60yr，BMI18-30kg/m2undergoing elective laparoscopiccholecystectomy(LC). Propofol was intravenously infusion to maintain BIS value at40-50.ECe50of remifentanil was determined by modified Dixon’s up-and-down methods, eachtime Ce increased/decreased by0.5ng/ml. Tracheal intubation was facilitated withcisatracurium0.1mg/kg after4min. The initial Ce of remifentanil was6.0ng/ml.Tracheal intubation and skin incision was made after the balance of remifentanil of thetarget effect-side and plasma concentrations(Cp). The cardiovascular reaction was definedas positive when SBP increased by15%,HR＞90bpm and15s persistented. The EC50(95%confidence interval) of remifentanil blunting responses to trancheal intubation andskin incision were calculated by Modified up-and-down rule analysis and Probitregression probabilistic analysis. Results: ECe50of remifentanil inhibiting cardiovascularresponse to tracheal intubation and skin incision combined with propofol, Modifiedup-and-down rule analysis were3.4(2.3-4.5)ng/ml and3.8(2.8-4.9)ng/ml; Probitregression probabilistic analysis were3.3(2.2~4.4)ng/ml and3.5(2.5~4.5)ng/mlrespectively. Conclusion: EC50of remifentanil inhibiting cardiovascular response totracheal intubation and skin incision combined with propofol in Uighurs were3.4(3.3) and3.8(3.5) ng/ml.