Reconsidering the seizure threshold? A retrospective study about seizure quality among patients with maintenance ECT

Antiepileptics in Electroconvulsive Therapy: A Mechanism-Based Review of Recent Literature

ABSTRACT

Although prior conventional wisdom strongly recommended complete discontinuation of medications increasing the seizure threshold before electroconvulsive therapy (ECT), more recent literature suggests that anticonvulsants should be considered a relative rather than an absolute contraindication to proceeding with therapy. Most literature regarding the use of use antiepileptic drugs in ECT focuses on antiepileptic mood stabilizers with which most psychiatrists are familiar. However, there is considerably less information available about the use of newer antiepileptics in conjunction with ECT, which may be prescribed to a patient with epilepsy or off-label for psychiatric reasons.In this article, we provide a mechanism-based review of recent available literature concerning the use of antiepileptics during ECT and discuss which medications have the most robust evidence supporting their continued use in select patients. Finally, we highlight important considerations for psychiatrists when deciding how to proceed with patients on antiepileptics who require ECT.

Dosing methods in electroconvulsive therapy: should the Scandinavian time-titration method be resumed?

AIM

To describe and evaluate the different dosing methods in ECT, and bringing back into focus the Scandinavian time-titration method.

METHOD

A narrative, unsystematic, and selective review and discussion.

RESULTS

There are five dosing methods: 1) The Scandinavian time-titration to tonic convulsion, using low-frequency pulses and a long maximal pulse train duration, was highly efficacious with right unilateral (RUL) ECT, comparable to bitemporal (BT) ECT. However, the device used went out of production in the 1990s. Because US devices until 1990 had a short maximal pulse train duration, time-titration went out of use. 2) Fixed high dosing at 50-100% of the device's maximal output, and 3) Formula-based dosing, initially the Age method, long prevailed in USA. Later, the Half-Age method was introduced for BT ECT. 4) Charge-dosing as a multiple of titrated seizure threshold (ST) demonstrated RUL and BT ECT to have comparable outcomes when dosed about six and two times the ST, respectively. 5) Dosing from benchmark is based on a high dose at the first session, to ensure a high peak heart rate and tonic-clonic convulsions. In later sessions the lowest dose producing similar outcomes is chosen.

CONCLUSIONS

No dosing method is documented superior to the others. Seizure threshold-based and benchmark dosing seems to be more accurate than fixed high and formula-based dosing. However, time-titration dosing makes it possible to adjust the dose at every session, and may be the most efficient method.

The ictal EEG in ECT: A systematic review of the relationships between ictal features, ECT technique, seizure threshold and outcomes

OBJECTIVE

To provide guidance for ECT practitioners in utilising the ictal EEG to inform treatment decisions.

METHODS

A systematic review of studies examining the ictal EEG, treatment technique, seizure threshold and treatment outcomes was conducted. MEDLINE, EMBASE and PsycINFO databases were searched up to July 31, 2019. Studies were included if they examined the use of ECT in human subjects and compared an ictal EEG analysis (either quantitative or manually rated) with either: a) clinical outcomes, b) seizure threshold/threshold change, c) ECT dosing decisions, or d) different aspects of ECT technique (comparison of different electrode placements, pulse widths, waveforms, or dose/dose relative to seizure threshold).

RESULTS

A total of 853 studies were identified, with 44 meeting inclusion criteria. A qualitative review revealed ictal EEG indices have been linked to therapeutic outcome, though the strength of this relationship appears modest. Ictal EEG features are influenced by variations in ECT treatment technique. Serial ictal EEG monitoring can detect changes in seizure threshold across an ECT course for right unilateral brief and ultrabrief pulse ECT.

CONCLUSION

While there is some relationship between ictal EEG manifestation and treatment outcomes, the primary utility of ictal EEG monitoring during an ECT course may lie in the capacity to detect changes in seizure threshold and adjust dosing accordingly. Prospective validation of a dosing regime informed by serial ictal EEG monitoring is warranted.