Electrical Dose and Seizure Threshold: Relations to Clinical Outcome and Cognitive Effects in Bifrontal, Bitemporal, and Right Unilateral ECT

Abstract

In patients allocated blindly and randomly to receive bitemporal, right unilateral, or bifrontal electroconvulsive therapy, seizure length, electrophysiologic characteristics (dynamic impedance, seizure threshold, and changes in threshold), and the degree of suprathreshold stimulation were recorded. The relations of these variables to clinical outcome and cognitive effects were determined. There were no differences in seizure length between groups, and there were no significant correlations between seizure length and any measure of clinical response. There were substantial differences between the groups in mean charge per treatment, with the right unilateral group receiving lower doses than either bilateral group. Convulsion time was inversely related to applied charge and the rate of increase in charge. There were no significant correlations between impedance, charge, energy, or rate of increase in charge on the one hand, and clinical improvement on the other. The increase in threshold during the course of treatment was not related to clinical change. Cognitive impairment was related to electrical dose only in the bifrontal group, which showed the least degree of treatment-induced intellectual dysfunction. Compared with bitemporal or right unilateral treatment, bifrontal electroconvulsive therapy yields the best ratio of benefits to side effects and should be given at threshold level to minimize cognitive loss.

Does Gender Influence Electroconvulsive Therapy Sessions Required across Psychiatric Diagnoses? A 5-Year Experience from a Single Center

“…However, one should exert caution in interpreting these findings as there are considerable variations in ECT parameters such as mode of delivery and electrode placement – unilateral or bifrontal or bitemporal,[15] intensities – threshold and suprathreshold,[1617] and frequency of sessions and variations in pulse–width – brief and ultrabrief,[12] all of which may conceivably influence stimulus dosing and response to ECT. Here, we have employed bitemporal threshold ECT for cases which, according to our knowledge, is most commonly practiced across India.…”

Electroconvulsive therapy hasn’t negative effects on short-term memory function, as assessed using a bedside hand-held device

“…Up to 55% of patients also report that the aforementioned side effects persist for months after ECT. 9,12,15,16,20-22 Prolonged confusional states might limit the use of ECT; in particular, at present, this issue is often reported as a subjective limitation during courses of ECT. Because the most common side effects of ECT are cognitive impairments that occur immediately after treatment, the use of a hand-held device in a bedside test setting seemed well suited to capture such effects.…”

Safety and Feasibility of Magnetic Seizure Therapy (MST) in Major Depression: Randomized Within-Subject Comparison with Electroconvulsive Therapy

“…The antidepressant properties of ECT and its effects on cognition are uncorrelated (Lerer et al, 1995;McElhiney et al, 1995;Sackeim, 1992) and considerable progress has been made in altering the ECT technique to maintain efficacy while reducing cognitive side effects. Nonetheless, the forms of ECT with the most wellestablished efficacy/side effect profile still result in a substantial side effect burden (Bailine et al, 2000;Delva et al, 2000;McCall et al, 2000;Sackeim et al, 1993Sackeim et al, , 2000b.…”