The investigators evaluate the effects of a subanesthetic dose of ketamine, administered as an adjunct to sevoflurane, on duration of seizure activity, hemodynamic profile and recovery times during electroconvulsive therapy (ECT) in patients with major depression.
Inclusion Criteria: * Major depressive patients Exclusion Criteria: * Pregnancy * Have a history of myocardial infarction in the previous six months * Atrial fibrillation or flutter * Heart block * Unregulated hypertension * Cerebrovascular diseases * A known drug allergy