Sevoflurane will be initiated, at 8% for anesthesia induction until loss of consciousness will achieve, at which point it will be discontinued. After the loss of consciousness remifentanil will be administered to Group sevoflurane-remifentanil in the form of a 1 µg/kg intravenous bolus.

Sevoflurane will be initiated, at 8% for anesthesia induction until loss of consciousness will achieve, at which point it will be discontinued. Placebo is 0.9% saline. After the loss of consciousness saline will be administered to Group sevoflurane-saline in the form of intravenous bolus.

Anesthetic induction will be achieved via 8% sevoflurane

Prior to anesthetic induction (T1); following anesthetic induction (T2); and 0, 1, 3, and 10 minute after the seizure have ended (T3, T4, T5, and T6, respectively).

During electroconvulsive therapy

Prior to anesthetic induction (T1); following anesthetic induction (T2); and 0, 1, 3, and 10 minute after the seizure have ended (T3, T4, T5, and T6, respectively).