Seizure threshold increases can be predicted by EEG quality in right unilateral ultrabrief ECT

• Published in: European archives of psychiatry and clinical neuroscience 2017-12, Vol.267 (8), p.795-801
• Main Authors: Gálvez, Verònica, Hadzi-Pavlovic, Dusan, Waite, Susan, Loo, Colleen K.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Cerebral Cortex - physiopathology; Convulsions & seizures; EEG; Electroconvulsive therapy; Electroconvulsive Therapy - methods; Electroencephalography - methods; Female; Humans; Male; Medicine; Medicine & Public Health; Mental Disorders - therapy; Middle Aged; Neurosciences; Original Paper; Psychiatry; Quality; Seizures - physiopathology; Titration
• ISSN: 0940-1334; 1433-8491
• DOI: 10.1007/s00406-017-0777-y

Increases in seizure threshold (ST) over a course of brief pulse ECT can be predicted by decreases in EEG quality, informing ECT dose adjustment to maintain adequate supra-threshold dosing. ST increases also occur over a course of right unilateral ultrabrief (RUL UB) ECT, but no data exist on the relationship between ST increases and EEG indices. This study ( n  = 35) investigated if increases in ST over RUL UB ECT treatments could be predicted by a decline in seizure quality. ST titration was performed at ECT session one and seven, with treatment dosing maintained stable (at 6–8 times ST) in intervening sessions. Seizure quality indices (slow-wave onset, mid-ictal amplitude, regularity, stereotypy, and post-ictal suppression) were manually rated at the first supra-threshold treatment, and last supra-threshold treatment before re-titration, using a structured rating scale, by a single trained rater blinded to the ECT session being rated. Twenty-one subjects (60%) had a ST increase. The association between ST changes and EEG quality indices was analysed by logistic regression, yielding a significant model ( p