ECT practice

Propofol anaesthesia in electroconvulsive therapy. Reduced seizure duration may not be relevant

BACKGROUND

The induction agent propofol is known to reduce electroconvulsive therapy (ECT) seizure duration. It is assumed that outcome from depression is adversely affected by this agent. This study compares propofol and methohexitone as induction agents for ECT.

METHOD

In a prospective, randomised, double-blind study 20 subjects with major depressive disorder (DSM-III-R criteria) received propofol or methohexitone anaesthesia. The Hamilton Depression Rating Scale and Beck Depression Inventory were used to assess depression before therapy, at every third treatment, and at the end of therapy. Seizure duration was measured using the cuff technique.

RESULTS

Mean seizure durations (P < 0.01) and mean total seizure duration (P < 0.01) were shorter in the propofol group. There was no difference in outcome.

CONCLUSIONS

Use of propofol may not adversely affect outcome from depression and it is not necessarily contraindicated as an induction agent for ECT. Our results should be interpreted cautiously, and larger studies are needed.

Would monitoring by electroencephalogram improve the practice of electroconvulsive therapy?

Estimates of seizure length made by the treating psychiatrist were compared with estimates made by six-channel EEG in 100 electroconvulsive treatments in 22 depressed patients. In 70 treatments the doctor observed a fit which was shorter than 25 seconds. No doctor restimulated a patient in such a case and on only three occasions was the electrical stimulus increased at the next treatment. EEG monitoring revealed that only 30 of the treatments resulted in a seizure of less than 25 seconds, and this was detected in almost all cases by the treating doctor. The potential value of EEG monitoring was to identify patients whose visible seizure was short but where cerebral seizure length was satisfactory. Trainee psychiatrists often mismanage patients who have short seizures.