Comparing Ketamine and Propofol Anesthesia for Electroconvulsive Therapy

To determine the effect of ketamine, compared to propofol, when used an an anesthetic agent for electroconvulsive therapy (ECT) in the treatment of major depressive disorder (MDD). We hypothesize that ketamine, compared to propofol, will improve the the symptoms of MDD when used as the anesthetic agent to facilitate ECT. Additionally, we hypothesize the dissociative and cardiovascular effects of ketamine will be minimal.

Treatment resistant depression is a common and disabling condition. The delayed onset of action and side effects exhibited by oral antidepressants are significant limitations. An alternative and well-established therapy is electroconvulsive therapy (ECT). ECT has rapid antidepressant effect beginning with the completion of the first session. Nevertheless, like oral medications, patients treated with ECT can develop treatment resistance or failure to respond. There is great need for a novel approach to treatment-resistant depression; one that that is safe, has rapid onset, and is sustained.

Pharmaceutical agents with rapid antidepressant effects are a new and promising paradigm in the research for treatment of MDD. A potential therapeutic target is glutamate based signal transmission because glutamate transmission is abnormally regulated in the limbic/cortical areas of many depressed people. Glutamatergic modulating agents, in particular ketamine, have been shown to induce rapid antidepressant effects both in both preclinical models and humans. Additionally, ketamine has been shown to have persistent antidepressive effect.

Presently worldwide, propofol is one of the most commonly used anesthetic agents for ECT. There are 2 main disadvantages to this practice. First, propofol has no antidepressive effect. Second, propofol is a potent anticonvulsant that may worsen the quality of the ECT induced seizures. A recent open-label trial compared ketamine to propofol for anesthesia during ECT and demonstrated a significant improvement of depression in the ketamine arm. Ketamine is routinely used to provide safe general anesthesia as well as procedural sedation, analgesia, and amnesia. The combination of the intrinsic antidepressant effects of ketamine with electroconvulsive therapy is a promising concept in clinical research.

This study will include planned interim analysis to ensure patients safety. This analysis will be performed by a statistician who is blinded to group allocation after 20 and after 40 patients. An independent safety committee will informed of the results of the interim analysis including side effects and complications and will have the option to adjust the drug dosage or to discontinue the trial.

Eligibility Criteria:
Inclusion Criteria:

* Fulfill the diagnostic criteria for major depression according to the Diagnostic and Statistical Manual of Mental Disorders (most recent edition)
* Failure to respond to at least 2 adequate drug therapies for the current depression episode
* MADRS score of 20 or above (moderate - severe
* ASA physical status classification I to III

Exclusion Criteria:

* Inability to obtain informed consent
* ASA physical status classification IV
* Complication by any serious physical diseases such as cardiovascular disease (including untreated HTN), respiratory disease, cerebrovascular disease, intracranial HTN (including glaucoma), or seizures
* Presence of foreign body (including pacemaker)
* Pregnancy
* Allergies to anesthetics used in study Includes: a) Ketamine b) Propofol c) Eggs d) Egg products e) Soybeans f) Soy products