Alfentanil has no proconvulsive effect during electroconvulsive therapy.

To the Editor: The efficacy of electroconvulsive therapy (ECT) relates to seizure duration.1 We explored whether alfentanil has an effect on seizure duration during anesthesia for ECT. In addition, we investigated the effects of alfentanil on the cardiovascular response during ECT, and on the duration of apnea. Etomidate was used as the anesthetic agent because it has the least effect on seizure duration compared with methohexital, propofol and thiopentone.2,3 After approval from the Hospital’s Ethics Committee, 21 consecutive patients were studied. In the second and subsequent five sessions patients received iv administration of metoclopramide 10 mg, glycopyrrolate 0.002–0.003 mg·kg–1, a bolus injection of either alfentanil (0.010–0.015 mg·kg–1 ) or placebo (0.9% NaCl) in identical volumes and etomidate 0.2–0.3 mg·kg–1 followed by succinylcholine 0.5–1.0 mg·kg–1. The administration of alfentanil or placebo was done in a doubleblind cross-over fashion with four sequences of six periods with two treatments. Blinded syringes were prepared by the pharmacy according to a computer-generated randomization list. Seizure duration was recorded by a two-channel electroencephalograph (EEG). Systolic and diastolic blood pressure (SBP, DBP), mean arterial pressure (MAP) and heart rate (HR) were monitored from arrival in the ECT suite until the patient started breathing adequately. Before the ECT, measurements were made once per minute and continuously thereafter. Differences in hemodynamic variables, seizureand apnea duration between the alfentanil and placebo sessions were estimated and tested using mixed model analysis of variance. Blood pressure and HR one hour before each treatment session was taken as covariate. There was no significant difference in mean seizure duration as measured with EEG between alfentanil and placebo sessions (placebo = 86 sec, alfentanil = 80 sec). Immediately before and after the stimulus the means of DBP, MAP and HR but not SBP were significantly lower after alfentanil than after placebo (Table). Apnea duration in the alfentanil sessions was on average 73 sec longer than in the placebo sessions (standard error = 17.5, P = 0.0001). Alfentanil itself does not lengthen seizure duration in combination with etomidate; it can be used to reduce the dosage of 198