Merits of EEG monitoring during ect: a prospective study on 485 patients

Abstract

Eliciting cerebral seizure during electroconvulsive therapy (ECT) is essential for therapeutic purposes. When it exceeds beyond 120 seconds (Freeman, 1995) i.e., prolonged, it adds to adverse effects of ECT. Estimating seizure duration using 'cuff method' alone has limitations. This study examined the merits of electroencephalographic (EEG) monitoring in routine ECT practice on a large representative sample. Modified ECT either unilateral or bilateral electrode placement, was administered to 485 patients under EEG monitoring at first ECT session. Ninety one (18.8%) patients had prolonged seizures of which only 59 would have been detected if 'cuff method' alone was used. Twenty nine (6%) patients had inadequate motor seizures but had adequate EEG seizure duration. Twenty five (5.2%) of them had no motor seizure and two such patients even had prolonged seizures. The prolonged seizure was unpredictable in majority. In conclusion, EEG monitoring during ECT is essential to detect both adequacy of cerebral seizure in patients having no or inadequate motor seizures and a/so to detect prolonged seizures.

Keywords: EEG monitoring; electroconvulsive therapy prolonged seizure.