Background: Among the drugs used for the induction of anesthesia for electroconvulsive therapy (ECT), thiopental induces a greater degree of cardiovascular alteration than other agents. Remifentanil has been found to reduce blood pressure and heart rate when administered as an adjuvant during general anesthesia, with unknown effects on the duration of motor or electroencephalographic seizure activity during ECT. The purpose of this prospective, randomized, double-blind, placebo-controlled, crossover study was to evaluate the effects of supplementing thiopental anesthesia with remifentanil on convulsion duration and cardiovascular response during ECT.
Methods: Twenty-four American Society of Anesthesiologists I and II patients receiving 6 sessions of ECT were randomly allocated to 2 groups. All patients were premedicated with atropine (0.4 mg, intravenously), then anesthesia was induced by thiopental (1.0 mg/kg), succinylcholine (0.5 mg/kg), and remifentanil (1.0 μg/kg) in the case group or normal saline (3 mL) in the control group in a crossover format. Stimulus amplitude for applying ECT was kept constant during the sessions of treatment in the course of study for each patient. Hemodynamic parameters, convulsion duration, and recovery parameters were recorded. Statistical analysis was done using paired t tests.
Results: There was no statistically significant difference between the groups regarding convulsion duration, recovery times to eye opening, obeying specific commands, and walking without help. Remifentanil significantly attenuated the increase in heart rate and arterial blood pressure (P < 0.05).
Conclusions: Remifentanil (1 μg/kg) administered before thiopental (1 mg/kg) has no adverse effect on the duration of ECT-induced convulsion and recovery time, but it can attenuate the increase in heart rate and arterial blood pressure.