Effects of different doses of fentanyl by target-controlled infusion on stress responses in patients undergoing abdominal surgery under general anesthesia / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of two different doses of fentanyl given by target-controlled infusion (TCI) on stress responses during operation under general anesthesia and evaluate the accuracy of TCI of fentanyl.Methods Thirty ASA Ⅰ-Ⅱ patients (14 males, 16 females) aged 24-69 yr, weighing 48-77 kg scheduled for elective abdominal surgery under general anesthesia were randomly divided into three groups with 10 patients in each group : group Ⅰ and Ⅱ received fentanyl by TCI with the target effect-site concentration set at 2 ng Ⅲ ml 1 (Ⅰ) and 4 ng ? ml-1 ( Ⅱ ) during induction and maintenance of anesthesia, while group Ⅲ received a bolus of fentanyl 3 ?g?kg-1 during induction of anesthesia. In addition to fentanyl, anesthesia was induced with propofol 2mg?kg-1 and vecuromum 0.1 mg?kg-1 and maintained with propofol infusion at 6 mg?kg-1?h-1 and intermittent i. v. doses of vecuronium BP (SBP, DBP, MAP ) , HR, SpO2 and PET CO2 were recorded before induction of anesthesia (T0 ,baseline), at the loss of consciousness (T1), immediately after tracheal intubation (T2), 5 and 10 rnin after intubation (T3 , T4), during skin incision (T5) and exploration of abdominal cavity (T6). Blood samples were obtained for determination of plasma norepinephrine (NE) and epinephrine (E) concentrations and blood glucose ( BG) and fentanyl concentrations at T0, T2, T4 and T5 by HPLC. Results There were no significant differences in sex, age and body weight among the three groups. There were no significant changes in plasma NE, E and BG concentrations, which were all within normal range in the three groups. The SBP and MAP in group Ⅲ were significantly lower than those in group Ⅰ and Ⅱ at T1 ( P