ABSTRACT
Objective To determine the half-effective target effect-site concentration (Ce) (EC50) of sufentanil required to inhibit the body movement during insertion of ureteroscopes when combined with propofol in patients undergoing transureteroscopic holmium laser lithotripsy. Methods Fifty ASA Ⅰ or Ⅱ patients of both sexes, aged 20-60 yr, BMI ＜ 30 kg/m2 , undergoing transureteroscopic holmium laser lithotripsy were randomly divided into 5 groups according to the different C es of sufentanil ( n = 10 each): group S1 (Ce 0.21 ng/ml), group S2(Ce 0.14 ng/ml), group S3(Ce 0.09 ng/ml), group S4(Ce 0.06 ng/ml), group S5(Ce 0.04 ng/ml). TCI of propofol with target plasma concentration set at 2.5-3.0 μg/ml was given. Sufentanil with the corresponding Ce was infused in each group. The ureteroscopes were inserted as soon as the patients lost consciousness and the effect-site concentration of sunfentanil was achieved. The response was defined as positive when body movement occurred within 1 min after insertion of ureteroscopes. The EC50 of sufentanil required to inhibit the body movement during insertion of ureteroscopes when combined with propofol and 95% confidence interval (CI) were calculated. Results The EC50 of sufentanil required to inhibit the body movement during insertion of ureteroscopes when combined with propofol was 0.084 ng/ml and 95% CI was 0.066-0.107 ng/ml. Conclusion The EC50 of sufentanil required to inhibit the body movement during insertion of ureteroscopes was 0.084 ng/ml when combined with propofol.