The Anaesthetic-ECT Time Interval in Electroconvulsive Therapy Practice--Is It Time to Time?

Area of Science:

• Neuroscience
• Psychiatry
• Anesthesiology

Background:

• Intravenous anaesthetics used in electroconvulsive therapy (ECT) possess anticonvulsant properties.
• The concentration of anaesthetics in the brain at seizure induction can influence seizure expression, which is linked to ECT efficacy.
• The interval between anaesthetic administration and ECT stimulus (anaesthetic-ECT interval) dictates this critical anaesthetic concentration.

Purpose of the Study:

• To investigate the impact of the anaesthetic-ECT time interval on the quality and duration of seizures induced by ECT.
• To determine if manipulating the anaesthetic-ECT interval can optimize seizure characteristics for improved therapeutic outcomes.

Main Methods:

• The study analyzed 771 ECT sessions across 84 patients undergoing right unilateral brief pulse ECT.
• Anaesthesia was induced with propofol (1-2 mg/kg) and succinylcholine (0.5-1.0 mg/kg).
• Seizure quality indices (amplitude, regularity, stereotypy, post-ictal suppression) and duration were assessed by a blinded rater; Linear Mixed Effects Models controlled for confounding variables.

Main Results:

• A statistically significant correlation was found between longer anaesthetic-ECT time intervals and higher quality seizures.
• Specifically, increased intervals led to significant improvements in seizure amplitude, regularity, stereotypy, and post-ictal suppression (p < 0.001).

Conclusions:

• The anaesthetic-ECT time interval is a crucial modifiable factor in electroconvulsive therapy practice.
• Extending this interval, where feasible, is recommended to enhance seizure quality and potentially improve ECT efficacy.
• Close interdisciplinary collaboration between anaesthetists and psychiatrists is vital for optimizing this parameter.