Up-and-down sequential method in determining median effective effect-site concentration (EC5O) of remifentanil required for inhibiting intubation-inducedhemodynamic responses in patients with parkinson's disease during target-controlled infusion of propofol / 第二军医大学学报

ABSTRACT

Objective To determine the median effective effect-site concentration (EC50) of remifentanil required to inhibit hemodynamic responses induced by intubation during target-controlled infusion (TCI) of propofol in patients with Parkinson' disease. Methods A1 (1 matched case control design was used in the study. Thirty-one ASA I E patients with Parkinson's disease undergoing general anesthesia were enrolled, and 31 controls were the hospitalized patients with non-Parkinson' disease during the same period (same sex, age ±3 years old). A TCI of propofol was used to maintain a predetermined effect-site concentrationof 3 fg/mL. The target effect-site concentration of remifentanil was determined by a modified Dixon' up-and-down sequential method. The initial target effect-site concentrations of remifentanil were 3 ng/mL in the two groups and the increments or decrements between the two consecutive patients were 0. 2ng/mL. A positive response meant that either the heart rate or the systolic blood pressure was elevated by 15% in the first5 min after intubation. Results There was no patient showed sign of muscle rigidity, and no patient recalled awareness during anesthesia in postoperative follow-up. During TCI of propofol, the EC50 of remifentanil required for inhibiting intubation induced hemodynamic responses for patientswith Parkinson' disease was 2. 20 ng/mL (95% confidence interval 1. 86-2. 60 ng/mL). And the EC50f remifentanil required for control group was significantly higher than for patients with Parkinson' disease (2. 93 ng/mL, 95% confidence interval 2. 72-3. 15 ng/mL). Conclusion When combined with TCI of propofol (target effect-site concentration 3 μg/mL), the EC50f remifentanil required for inhibiting intubation induced hemodynamic responses for patients with Parkinson' disease is less than that for non-Parkinson' disease.