1. Vascular Surgery, Unit Department of Surgery, Medical School, University of Ioannina, 45110 Ioannina, Greece
2. Department of Intensive Care Unit, Medical School, University of Ioannina, 45110 Ioannina, Greece
3. Department of Anesthesiology, Medical School, University of Ioannina, 45110 Ioannina, Greece