Ketamine Anesthesia in Electroconvulsive Therapy

A Randomized Comparison of Ketamine and Methohexital Anesthesia for Electroconvulsive Therapy (ECT) in Depression

Does the use of ketamine as the anesthetic medication in electroconvulsive therapy (ECT) accelerate the antidepressant effect of ECT?

The study hypothesis was that depressed subjects receiving ECT with ketamine as the anesthetic agent would demonstrate a faster rate of improvement, defined as lower depression ratings after the second ECT than depressed patients receiving ECT with the usual anesthetic agent.

There are several drugs available to induce anesthesia for electroconvulsive therapy (ECT), a psychiatric treatment for major depressive illness. The most commonly utilized of these include methohexital, thiopental, etomidate, and propofol. Recently, there has been interest in the use of ketamine in sub-anesthetic doses to treat major depressive illness.

In this randomized, blinded trial, depressed subjects scheduled to be treated with ECT were anesthetized with either ketamine or methohexital at doses of approximately 1.0 mg/kg for each drug. Patients received the same drug for up to six of their ECT treatments. Outcome measures included assessments of depressive severity, cognition, post-anesthesia side effects, and hemodynamics.

Subjects were to be followed with as long as they were receiving inpatient ECT treatments. The number of treatments was determined entirely by their primary psychiatric team, also blind to anesthetic, as per usual care. In other words, this study did not determine when to terminate the ECT course.

Inclusion criteria:

• Diagnosis of depression, either unipolar or bipolar
• Subjects receiving ECT at the Mayo Clinic

Exclusion criteria:

• Subjects not giving their own consent to ECT
• Subjects with schizophrenia, schizoaffective disorder, or dementia
• Subjects diagnosed with a major neurological disorder such as epilepsy, Parkinson disease, multiple sclerosis, or a neurodegenerative dementia.