Anesthetic Switching During the Acute ECT Course: A Single-Center Retrospective Cohort Study

During the acute ECT course, physicians may change induction anesthetics when seizure characteristics are suboptimal, particularly with limited clinical response. Although common in practice, anesthetic switching has undergone limited systematic study regarding frequency or effects on seizure characteristics. We examined the prevalence and impact of anesthetic switching to inform clinical care and the neurobiology of electrically induced seizures.

We conducted a retrospective cohort study of all patients aged 17 years or older undergoing ECT at Albany Medical Center between 2020 and May 2025. Included subjects received at least 2 ECT sessions within an acute ECT course. The research was determined by the Albany Med IRB to be exempt from IRB review and approval.

Seventy-three patients (35 male/38 female) undergoing 82 acute ECT courses were included, 79% for unipolar or bipolar depression. Age (mean±SD) was 56±17 years. An anesthetic was switched in 22/82 (27%) courses. Multivariate logistic regression found no associations between switching and age, sex, or depression diagnosis. The most frequent switch was propofol to methohexital (16/22, 73%). Compared with the prior session, motor seizures were 15 seconds longer (95% CI: 6-25 s, P=0.0038) and EEG seizures were 24 seconds longer (95% CI: 15-33 s, P<0.0001).

Anesthetic switching occurred in over a quarter of acute ECT courses at this site. The predominant change, propofol to methohexital, was associated with markedly longer seizures. Thus, patients clinically identified for a switch to a less anticonvulsant induction agent retain the capacity for longer seizures. Future studies are warranted to clarify how anesthetic switching influences treatment outcomes.