1. Department of Emergency Medicine, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
2. Department of Anesthesia & Intensive Care, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
3. Second Department of Anesthesiology, National and Kapodistrian University of Athens, Attikon University Hospital, 12462 Athens, Greece
4. Department of Surgery, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece