[Placement of stimulus electrodes and heart rate during electroconvulsive therapy].
OBJECTIVE
Bifrontal stimulation in electroconvulsive therapy (ECT) has been increasingly administered and evaluated over the past years. However, no attention has been paid to cardiac side effects of this novel form of treatment during the application of the electrical stimuli.


METHODS
Cardiac responses to different electrode positions were compared intraindividually, using synchronised electrocardiograms and waveforms of pulse oximetry.


RESULTS
Unilateral ECT gave rise to a marked cardiac response during stimulation. Intervals between two consecutive heartbeats increased from 0.6 ± 0.0 sec to 4.1 ± 3.4 sec (mean ± standard deviation). In contrast, stable heart actions were documented in the same patients during bifrontal stimulation.


CONCLUSIONS
The placement of the stimulus electrodes for ECT determines the incidence of asystole events during stimulation. Bifrontal electrode positioning results in less activation of the vagus nerve than unilateral treatment. The longer distance from the electrode site to the nerve in bifrontal treatment could account for these findings.
Nagler
J
J
Klinikum Schloß Winnenden (Ärztlicher Direktor Dr. G. Hetzel). JosefNagler@gmx.de
D000368:Aged; D000369:Aged, 80 and over; D000758:Anesthesia; D004562:Electrocardiography; D004565:Electroconvulsive Therapy / Q000009:adverse effects* / Q000379:methods*; D004566:Electrodes; D005260:Female; D006331:Heart Diseases / Q000209:etiology; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D010092:Oximetry; D014630:Vagus Nerve / Q000502:physiology