The Electro-Convulsion-Therapy (ECT) is a well accepted treatment option in severe depression. The quality of ECT is evaluated basing on minimal seizure duration (>15sec), the sympathic response and the postictal EEG-suppression.

For the treatment general anaesthesia is needed. On the other hand anaesthesia strongly influences the quality of the seizure. The goal is to find an anaesthesia-depth that is needed for the well-being of the patient and allows a good ECT.

In daily routine the dose of anesthetic agents and the assesment of anesthesia-depth is based on the subjective estimation of the anesthetist and also on ealier interventions.

The aim of the study is to assess any correlation between measured anesthesia-depth using the Narcotrend TM and the Quality of the ECT.

Inclusion Criteria:

• ASA (American Society of Anesthesiologists) Physical Satus I-3
• >18 years < 90 years
• Signed informed consent

Exclusion Criteria:

• Refusal of the patient

Patient sceduled for elective ECT for the Treatment of severe deppression