1. Department of Medicine, Washington University School of Medicine, St Louis, MO, USA
2. Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA, USA
3. Division of Pulmonary and Critical Care Medicine, Mount Auburn Hospital, Cambridge, MA, USA
4. Boston MedFlight, Bedford, MA, USA
5. Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
6. Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA, USA
7. Department of Emergency Medicine, Lahey Hospital & Medical Center, in memoriam, Burlington, MA, USA
8. Department of Emergency Medicine, Tufts Medical Center, Boston, MA, USA