1. Dipartimento di Anestesia, Rianimazione e Emergenza-Urgenza, Fondazione IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico) Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
2. Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
3. Department of Anaesthesia and Intensive Care Medicine, Humanitas Clinical and Research Center–IRCCS, Rozzano, Italy
4. Department of Biomedical Sciences, Humanitas University, Milan, Italy
5. Humanitas Gavazzeni, Bergamo, Italy
6. Department of Anesthesiology, Intensive Care and Emergency Medicine, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
7. Dipartimento di Scienze biotecnologiche di base, cliniche intensivologiche e perioperatorie, Università Cattolica del Sacro Cuore, Rome, Italy
8. Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
9. Department of Anesthesia and Intensive Care Medicine, Azienda Socio Sanitaria Territoriale (ASST) Monza–Ospedale San Gerardo, Monza, Italy
10. Department of Anaesthesia and Intensive Care, ASST Papa Giovanni XXIII, Bergamo, Italy
11. Università degli Studi dell’Insubria, Azienda Ospedaliera Ospedale di Circolo e Fondazione Macchi, Varese, Italy
12. Department of Anesthesiology and Intensive Care, ASST Mantova–Ospedale Carlo Poma, Mantova, Italy
13. Department of Anaesthesiology, Intensive Care and Perioperative Medicine, Spedali Civili University Hospital, Brescia, Italy
14. Direzione Generale (DG) Welfare, Lombardy Region, Milan, Italy
15. Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientific Institute, Milan, Italy
16. Department of Anesthesiology and Intensive Care, ASST Cremona–Ospedale di Cremona, Cremona, Italy
17. Department of Anesthesiology and Intensive Care, ASST Lecco–Ospedale di Lecco, Lecco, Italy
18. Dipartimento di Anestesia e Rianimazione, Grande Ospedale Metropolitano Niguarda, Milan, Italy
19. Department of Intensive Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
20. Department of Clinical-Diagnostic, Surgical and Pediatric Sciences, University of Pavia, Pavia, Italy
21. Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, Brescia, Italy
22. Department of Anesthesia and Intensive Care, Fondazione Poliambulanza Hospital, Brescia, Italy
23. Department of Anesthesia and Intensive Care, ASST Rhodense–Presidio di Rho, Milano, Italy
24. Anesthesia and Intensive Care Medicine, Policlinico di Sant’Orsola, Alma Mater Studiorum University of Bologna, Bologna, Italy
25. Department of Anesthesiology and Intensive Care, ASST Fatebenefratelli Sacco, Luigi Sacco Hospital, Polo Universitario, University of Milan, Milan, Italy
26. Direzione Scientifica, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
27. Dipartimento Emergenza Urgenza, Unità Operativa Complessa (UOC) Anestesia e Rianimazione, ASST, Lodi, Italy
28. Division of Pulmonary and Critical Medicine, Massachusetts General Hospital, Boston
29. Health Protection Agency of Pavia, Pavia, Italy
30. for the COVID-19 Lombardy ICU Network