1. Anesthesia and Intensive Care Unit, and Pain Relief and Palliative Care Unit, La Maddalena Clinic for Cancer, SAMOT, Palermo
2. Department of Anesthesia and Intensive Care, Buccheri La Ferla Fatebenefratelli Hospital, Palermo
3. Department of Hygiene and Microbiology, University of Palermo, Palermo
4. SAMOT, Palermo