1. 4th Surgical Department, Aristotle University of Thessaloniki, General Regional Hospital "George Papanikolaou," Thessaloniki, Greece
2. 4th Surgical Department, Aristotle University of Thessaloniki, General Regional Hospital "George Papanikolaou," Thessaloniki, Greece,
3. Department of Gastroenterology, Aristotle University of Thessaloniki, General Regional Hospital "George Papanikolaou," Thessaloniki, Greece
4. Intensive Care Unit, Aristotle University of Thessaloniki, General Regional Hospital "George Papanikolaou," Thessaloniki, Greece
5. Department of Anesthesiology Aristotle University of Thessaloniki, General Regional Hospital “George Papanikolaou," Thessaloniki, Greece