瑞芬太尼抑制双腔管插管时心血管反应的半数有效血浆浓度分析

目的测定复合异丙酚靶控输注时,瑞芬太尼抑制双腔管插管时心血管反应的半数有效血浆浓度。方法择期需行双腔管插管的开胸手术患者30例,采用3.0μg/mL的血浆靶浓度靶控输注异丙酚,待脑电双频指数(BIS)降至45～55,再静脉注射维库溴铵,然后靶控输注瑞芬太尼,达靶浓度后插入双腔气管导管。瑞芬太尼的血浆靶浓度按上下序贯法确定。结果瑞芬太尼抑制双腔管插管时心血管反应的Cp50为3.0 ng/mL,95%可信区间为2.8～3.1 ng/mL。结论复合靶控输注3.0μg/mL异丙酚时,瑞芬太尼抑制双腔管插管时心血管反应的Cp50为3.0 ng/mL。

Plasma concentration of remifentanil blunting cardiovascular responses to double lumen intubation in 50% of patients

Objective To determine the most suitable plasma concentration of remifentanil blunting cardiovascular responses to double-lumen intubation in 50% of patients.Methods Thirty patients undergoing elective thoracotomy with double lumen intubation were enrolled in the study.Anesthesia was performed using a TCI for administering propofol with a plasma concentration of 3.0 μg/mL.After obtaining a stable BIS value ranging between 45 and 55,vecuronium was infused for muscle relaxation,and then remifentanil infusion started.When the remifentanil plasma concentration reached a determined level,all patients underwent direct laryngoscopy with double lumen intubation.The dose of remifentanil given to each patient was determined by a modified Dixon′s up-and-down method.Results The Cp50 of remifentanil for block of cardiovascular responses to double lumen intubation was 3.0 ng/mL(95% CI:2.8～3.1 ng/mL).Conclusion The remifentanil plasma concentration is 3.0 ng/mL given after a propofol plasma concentration of 3 μg/mL in blunted cardiovascular responses to double-lumen intubation in 50% of patients.