1 Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy. dlgrieco@outlook.it.
2 Department of Anesthesiology and Intensive Care Medicine, Catholic University of The Sacred Heart, Fondazione 'Policlinico Universitario A. Gemelli' IRCCS, L.Go F. Vito, 00168, Rome, Italy. dlgrieco@outlook.it.
3 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada.
4 Department of Medicine, Division of Respirology, University Health Network/Sinai Health System, Toronto, Canada.
5 Adult Intensive Care Unit, University Hospital and University of Lausanne, Lausanne, Switzerland.