Seizure threshold in electroconvulsive therapy: I. Initial seizure threshold.
We measured initial seizure threshold by means of a structured stimulus dosage titration procedure in a clinical sample of 111 depressed patients undergoing brief-pulse, constant-current electroconvulsive therapy (ECT). Initial seizure threshold was approximately 60 millicoumbs (mc) (10 Joules) on average, but varied widely (6-fold) across patients. Initial seizure threshold was predicted by four variables: electrode placement (higher with bilateral), gender (higher in men), age (higher with increasing age), and dynamic impedance (inverse relationship). Use of neuroleptic medication was associated with a lower seizure threshold. EEG seizure duration was inversely related to initial seizure threshold, but no other relations with seizure duration were found. These findings may have important clinical implications for stimulus dosing strategies in ECT.
Coffey
C E
CE
Department of Psychiatry (Neuropsychiatry), Medical College of Pennsylvania, Pittsburgh, USA.
Lucke
J
J
Weiner
R D
RD
Krystal
A D
AD
Aque
M
M
D000328:Adult; D000367:Age Factors; D000368:Aged; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects; D001714:Bipolar Disorder / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D002540:Cerebral Cortex / Q000187:drug effects / Q000503:physiopathology; D003866:Depressive Disorder / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D004292:Dominance, Cerebral / Q000502:physiology; D004565:Electroconvulsive Therapy / Q000379:methods*; D004569:Electroencephalography / Q000187:drug effects; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011292:Premedication; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D012684:Sensory Thresholds / Q000187:drug effects / Q000502:physiology
D014150:Antipsychotic Agents