The effects of different effect-site target-controlled infusion concentration of remifentanil to the ECe50 of propofol with target-controlled infusion in eldly patients.

Objective: To investigate the effects of different target-controlled infusion concentration of remifentanil to the ECe50 of propofol with target-controlled infusion in eldly patients.Methods: Sixty patients aged 65-85,undergoing transurethral resection of prostate,were divided randomly into three groups(R0.5,R1.0,R1.5) with 20 cases each and given remifentanil with the target concentration of 0.5,1,1.5 ng/ml,respectively.Propofol was performed when remifentanil reached to the target concentration.Propofol was given by up and down method according to the movement of body and the ratio of two close effect concent rations was 1.2.Results: The ECe50 of the R0.5 group was 2.37 μg/ml.The 95% confidence interval was 2.22-2.53 μg/ml.The ECe50 of the R1.0 group was 1.84 μg/ml.The 95% confidence interval was 1.75-1.94 μg/ml.The ECe50 of the R1.5 group was 1.66 μg/ml.The 95% confidence interval was 1.60-1.71.Conclusion: The increasing of target-controlled infusion concentration of remifentanil help to decrease the ECe50 of propofol,but the danger of anesthesia will be bigger accordingly.