Efficiency of the stimulus characteristics of ECT.
OBJECTIVE
Greater ECT stimulus efficiency allows for a lower stimulus dose and should diminish the side effects of ECT.


METHODS
Four different ECT stimuli of identical charge (average mC=2.5 times age) with pulse widths of 0.5 msec and 1 msec and frequencies of 30 Hz and 60 Hz, respectively, were compared for efficiency. The stimuli were applied in a balanced order to each of 24 subjects. Asymmetric bilateral electrode placement was used.


RESULTS
Peak heart rates were higher with the 0.5-msec pulse width than the 1-msec pulse width. Seizure induction was more successful with the 0. 5-msec pulse width than the 1-msec pulse width. Stimulus frequency had no effect on heart rate or seizure induction.


CONCLUSIONS
The pulse width of 0.5 msec is more efficient than the 1-msec pulse width. The "half-age" dose for the first bilateral ECT treatment is usually successful for subsequent ECTs when the 0.5-msec pulse width is used.
Swartz
C M
CM
Department of Psychiatry, Southern Illinois University, Springfield, IL62794-9642, USA. ectdoc@pol.net
Manly
D T
DT
D000328:Adult; D000367:Age Factors; D000368:Aged; D003866:Depressive Disorder / Q000628:therapy; D004558:Electric Stimulation; D004565:Electroconvulsive Therapy / Q000009:adverse effects / Q000379:methods* / Q000706:statistics & numerical data; D004566:Electrodes; D005260:Female; D007839:Functional Laterality; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged