1. Department of Health Sciences, University of Milan, 20122 Milan, Italy
2. Department of Anesthesia and Intensive Care, ASST Santi Paolo e Carlo, San Paolo University Hospital Milan, 20142 Milan, Italy
3. Coordinated Research Center on Respiratory Failure, University of Milan, 20122 Milan, Italy
4. Division of Respiratory Diseases, Luigi Sacco University Hospital, ASST Fatebenefratelli-Sacco, 20157 Milan, Italy
5. Department of Biomedical and Clinical Sciences, Università degli Studi di Milano, 20157 Milan, Italy