The aim of this study was to evaluate the effect of sevoflurane or ketamine on the QTc and Tp-e interval during in patients with major depression.

Patients enrolled in the study are randomly allocated by computer-generated random numbers to receive either sevoflurane or ketamine for their initial ECT session. They subsequently receive an alternative study drug in their next session, continuing to alternate between drugs at each session until the sixth session. In group S, sevoflurane are initiated at %8 sevoflurane for anesthesia induction and maintained at 2% to %4 until the electrical stimulus is delivered, In group K, ketamine are given to 1mg/kg ıv bolus.

Electrical stimulus is delivered via bilateral frontotemporal electrodes.The mean arterial pressure (MAP), HR, and ECG are recorded before anesthetic induction (T1), after anesthetic induction (T2) and at 0, 1, 3, 10 min after the seizure ended (T3, T4, T5 and T6, respectively).The QT interval and Tp-e interval are measured by one author, who was unaware of group allocation.

Inclusion Criteria:

• Unpremedicated
• American Society of Anesthesiologists (ASA) I-II the patients
• Major depressions patients scheduled for ECT sessions

Exclusion Criteria:

• pregnant
• with permanent pacemakers,
• diabetes mellitus,
• atrial fibrillation,
• electrolyte imbalance,
• patients taking antiarrhythmics and β-blockers.