1. Department of Anesthesia and Critical Care, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
2. Department of Anesthesia and Intensive Care, A. Manzoni Hospital, ASST Lecco, Lecco, Italy
3. Department of Anesthesia and Intensive Care, ASST Papa Giovanni, Bergamo, Italy
4. Department of Emergency and Intensive Care, ASST Monza, Monza, Italy
5. School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
6. Epidemiology Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
7. Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.