[Electroconvulsive therapy in treatment resistant depression: What is new?]

Despite major advances in the treatment of mood disorders, major depression, a common mental disorder, remains a serious public health problem. Electroconvulsive therapy (ECT) regardless of the anesthetic agent used, is the most effective form of treatment in major depression and the gold standard therapy in treatment resistant depression. Ketamine is one of the anesthetic drugs approved by the Αmerican Psychiatric Association Task Force Report for use in ECT. However, it has been used infrequently as an anesthetic in ECT. The initial reports suggested that ketamine has antidepressant properties resulting in rapid antidepressant response when administered in subanesthetic dose (0.5 mg/kg) in slow intravenous injection in patients suffering from depression. In recent trials has been reported that ketamine as the only anesthetic or as an adjunctive to another anesthetic agent may enhance the antidepressant effect of ECT either by increasing efficacy or by producing a rapid antidepressant response. ECT with ketamine may also cause less cognitive side effects. The most notable limitations of these studies are the small number of patients enrolled and several methodological differences (patients characteristics, electrode placements, titration method, anesthetic agent used with ketamine). The results of the clinical trials have been summarized in six meta-analysis and suggest that ketamine when used as a sole anesthetic agent or as an adjunctive anesthetic in ECT may accelerates the antidepressant response but does not augment ECT efficacy. It also does not improve the cognitive profile of the treatment. Larger, double-blind randomized controlled trial are needed for a definite conclusion.