ABSTRACT
Objective To investigate whether the median(50%)effective effect-concentration(EC50)of propofol inducing loss of consciousness (LOC) varies. Methods 56 patients undergoing gastroscopy under general anaesthesia were enrolled on the study. Anaesthesia was conducted with a target-controlled infusion(TCI) of propofol. The initial target effect-site propofol concentration (Ceprop) was 5.00 μg/mL and was adjusted stepwise by 0.50μg/mL by an up-down sequential method to reach no-movement. Results Propofol EC50 to induce no-movement was higher in patients with anxiety than those without anxiety(6.46μg/mL vs. 5.75μg/mL,P<0.05). Conclusions During general anaesthesia ,patients with anxiety had a higher propofol EC50 for no-movement compared with those without anxiety. Differences in preoperative anxiety levels may reduce anaesthetic effects.
ABSTRACT
Objective To investigate whether the median(50%)effective effect-concentration(EC50)of propofol inducing loss of consciousness (LOC) varies. Methods 56 patients undergoing gastroscopy under general anaesthesia were enrolled on the study. Anaesthesia was conducted with a target-controlled infusion(TCI) of propofol. The initial target effect-site propofol concentration (Ceprop) was 5.00 μg/mL and was adjusted stepwise by 0.50μg/mL by an up-down sequential method to reach no-movement. Results Propofol EC50 to induce no-movement was higher in patients with anxiety than those without anxiety(6.46μg/mL vs. 5.75μg/mL,P<0.05). Conclusions During general anaesthesia ,patients with anxiety had a higher propofol EC50 for no-movement compared with those without anxiety. Differences in preoperative anxiety levels may reduce anaesthetic effects.