Unilateral nondominant electrode placement as a risk factor for recall of awareness under anesthesia during electroconvulsive therapy

Effect of quantitative consciousness index on seizure parameters during electroconvulsive therapy in patients with major depressive disorder

BACKGROUND

Electroconvulsive therapy (ECT) is both an effective treatment for patients with major depressive disorder (MDD) and a noxious stimulus. Although some studies have explored the effect of sedation depth on seizure parameters in ECT, there is little research on the noxious stimulation response to ECT. In this study, we used two electroencephalography (EEG)-derived indices, the quantitative consciousness (qCON) index and quantitative nociceptive (qNOX) index, to monitor sedation, hypnosis, and noxious stimulation response in patients with MDD undergoing acute ECT.

AIM

To evaluate the effect of anesthesia depth based on the qCON and qNOX indices on seizure parameters.

METHODS

Patients with MDD (n = 24) underwent acute bilateral temporal ECT under propofol anesthesia. Before ECT, the patients were randomly divided into three groups according to qCON scores (qCON60-70, qCON50-60, and qCON40-50). Continuous qCON monitoring was performed 3 minutes before and during ECT, and the qCON, qNOX, vital signs, EEG seizure parameters, and complications during the recovery period were recorded. The 24-item Hamilton Rating Scale for Depression, Zung's Self-rating Depression Scale, and Montreal Cognitive Assessment scores were evaluated before the first ECT session, after the fourth ECT session, and after the full course of ECT.

RESULTS

A total of 193 ECT sessions were performed on 24 participants. The qCON index significantly affected the EEG seizure duration, peak mid-ictal amplitude, and maximum heart rate during ECT (P < 0.05). The qNOX index significantly affected the post-ictal suppression index (P < 0.05). Age, number of ECT sessions, and anesthetic-ECT time intervals also had a significant effect on EEG seizure parameters (P < 0.05). However, there were no significant differences in complications, 24-item Hamilton Rating Scale for Depression scores, Zung's Self-rating Depression Scale scores, or Montreal Cognitive Assessment scores among the three groups (P > 0.05).

CONCLUSION

Electrical stimulation at a qCON index of 60-70 resulted in better EEG seizure parameters without increasing complications in patients with MDD undergoing bilateral temporal ECT under propofol anesthesia.

Degree of Postictal Suppression Depends on Seizure Induction Time in Magnetic Seizure Therapy and Electroconvulsive Therapy

OBJECTIVES

Anesthesia is required for both magnetic seizure therapy (MST) and electroconvulsive therapy (ECT), although it has anticonvulsant properties. In this case, bispectral index (BIS) monitoring, a specific electroencephalogram-derived monitoring, can be used to find the optimal seizure induction time during anesthesia to elicit adequate seizures. A measurement of seizure adequacy in electroencephalogram is the postictal suppression. The purpose of this study was to investigate the influence of seizure induction time on the degree of postictal suppression by comparing BIS versus no-BIS monitoring in MST and ECT.

METHODS

Twenty patients with treatment-resistant depression were randomly assigned to either MST or ECT. Each patient underwent 3 treatments with the determination of seizure induction time by defined prestimulation BIS (BIS condition) and 3 treatments with determination of seizure induction time by controlled clinical trial protocol (no-BIS condition). Statistical analysis was calculated by repeated-measures analysis of variance.

RESULTS

The degree of postictal suppression was more pronounced in both MST and ECT, with BIS monitoring. In this connection, no differences between MST and ECT were found. Seizure induction time was significantly later in the BIS condition (181.3 ± 6 seconds) compared with the no-BIS condition (114.3 ± 12 seconds) (P < 0.001).

CONCLUSIONS

Adequacy of seizures, in the form of the degree of postictal suppression, was superior by determining the seizure induction time with BIS in both MST and ECT. Further research is needed to investigate the correlation between the degree of postictal suppression and treatment response.

Stimulus characteristics in electroconvulsive therapy. A pragmatic review

The process of normalization electroconvulsive therapy (ECT) requires, among other actions, disseminating the latest information on this technique. One of the most complex aspects is the electrical stimulus, whose knowledge should be spread and put into practice. In this paper we review the available information about frequency and number of ECT sessions, and efficacy of each electrode placement. We also present two approaches to determine the ECT charge: stimulus titration versus age-based method; and the limitations of the summary metrics of charge, being necessary to expand our knowledge of the parameters that configure the stimulus: duration, current amplitude frequency and pulse width.

Position statement and guidelines on unmodified electroconvulsive therapy

BACKGROUND

In modern day psychiatric practice, it is assumed as a matter of fact that when electroconvulsive therapy (ECT) is administered, it will be administered under anesthesia and with succinylcholine (or its equivalent) modification. Yet, as surveys indicate, there is considerable practice of unmodified ECT in developing countries and, to a small extent, in the developed world, as well.

MATERIALS AND METHODS

This document examines historical and recent literature on the geographical practice, physiology, efficacy, and adverse effects of unmodified ECT. Particular attention is paid to musculoskeletal risks.

RESULTS

Although almost all the research is of poor methodological quality, there is a good reason to accept that unmodified ECT is associated with a wide range of adverse consequences, important among which are musculoskeletal complications, pre-ECT anxiety, and post-ECT confusion. However, it appears from recent data that these risks are not as large as historically portrayed. Possibly explanations are suggested, with seizure modification using parenteral benzodiazepines as a special possibility.

CONCLUSIONS

Under exceptional circumstances, if ECT is strongly indicated and seizure modification with succinylcholine is not feasible, unmodified ECT, especially benzodiazepine-modified ECT, may be a viable option. A detailed set of recommendations for such use of unmodified ECT is proposed along with necessary checks and balances. This document has been approved by the Indian Psychatric Society, the Indian Association of Biological Psychiatry, and the Indian Association of Private Psychiatry (which commissioned the preparation of the document).

The safety and efficacy of benzodiazepine-modified treatments as a special form of unmodified ECT

BACKGROUND

Muscle relaxants reduce musculoskeletal morbidity with electroconvulsive therapy (ECT) but need to be administered under general anesthesia. The administration of anesthesia is not always possible for patients prescribed ECT. Consequently, unmodified ECT is still widely practiced, especially in developing countries.

METHODS

We prospectively assessed musculoskeletal morbidity in consecutive patients who received unmodified bitemporal ECT during a part or the whole of their ECT course. All patients were pretreated with an intravenous benzodiazepine (usually diazepam, 10 mg) to effect sedation, anxiolysis, and limited skeletal muscle relaxation. Anteroposterior and lateral digital x-rays of the thoracolumbar spine were obtained after the last unmodified treatment.

RESULTS

Fifty-six patients aged 11 to 49 years and with a mean body mass index of 23.0 received a total of 162 (mean, 2.9) unmodified ECTs. There was significant attenuation of psychopathology ratings. Against our expectations, no patient developed clinical or radiological evidence of orthopedic morbidity; however, in 2 patients, the x-rays revealed old spinal fractures. Twelve patients had spots of oral bleeding after ECT. Whereas 5 patients experienced mild, transient, self-limiting postictal confusion, only one had confusion which required medical termination. Five patients complained of body ache and one of memory impairment. There were no other adverse events.

CONCLUSIONS

The complete absence of orthopedic morbidity with benzodiazepine-modified ECT contrasts with historical descriptions of a 20% to 40% risk with unmodified ECT. We speculate that the limited muscle relaxant action of the pre-ECT parenteral benzodiazepine may have had protective effects. If so, if ECT is urgently indicated but anesthesia and hence conventional muscle relaxants cannot be administered, benzodiazepine-modified ECT may be a safer alternative to unmodified ECT. This suggestion merits wide attention because of its public health importance in countries with poor medical infrastructure, where unmodified ECT is still widely practiced.