The study aims to compare outcomes of Electroconvulsive Therapy (ECT) using ketamine versus methohexital anesthesia in depressed patients. The investigators hypothesize that patients who receive ketamine anesthesia during ECT will achieve remission status faster than those receiving methohexital anesthesia. Also, at the end of the ECT course subjects will display fewer cognitive side effects compared to those treated with methohexital anesthesia.