1. Department of Emergency Medicine, North Side Hospital Forsyth, Cumming, GA 30041, USA
2. Radiology and 1st Critical Care Departments, Evangelismos University Hospital, 10676 Athens, Greece
3. Intensive Care Unit, General State Hospital of Athens, 10676 Athens, Greece
4. Department of Biostatistics, Texas Tech University, Lubbock, TX 79409, USA
5. Division of Pulmonary and Critical Care Medicine, Hofstra North Shore-LIJ School of Medicine, The Long Island Jewish Medical Center, New York, NY 11549, USA