1. First Department of Critical Care Medicine and Pulmonary Services, Evangelismos Hospital, National and Kapodistrian University of Athens Medical School, Athens, Greece.
2. Department of Otorhinolaryngology-Head and Neck Surgery, University General Hospital of Ioannina, Ioannina, Greece.
3. Department of Medicine, Division of Pulmonary and Critical Care Medicine, Weill Cornell Medicine, New York, NY.