1 Unit of Anaesthesia, Intensive Care and Pain Management, Department of Medicine, Campus Bio Medico University and Teaching Hospital, Rome, Italy.
2 Health Prevention Directorate, Italian Ministry of Health, Italy.
3 Department of Anesthesia and Intensive Care Unit, San Salvatore Academic Hospital of L'Aquila, L'Aquila, Italy.
4 Department of Life, Health, and Environmental Sciences, University of L'Aquila, S. Salvatore Hospital, L'Aquila, Italy.
5 Medical Statistic and Molecular Epidemiology Unit, University of Biomedical Campus, Rome, Italy.
6 Fondazione Policlinico Universitario A. Gemelli, IRCCS, Institute of Anaesthesia and Intensive Care, Catholic University of the Sacred Heart, Rome, Italy.
7 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy; Department of Anesthesiology, Intensive Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy. Electronic address: gristag@gmail.com.