1. University of Maryland School of Medicine, The R Adams Cowley Shock Trauma Center, Department of Surgical Critical Care, Baltimore, Maryland
2. University of Maryland School of Medicine, Department of Emergency Medicine, Baltimore, Maryland
3. George Washington University School of Medicine and Health Sciences, Department of Emergency Medicine, Washington, DC
4. University of Maryland School of Medicine, The R Adams Cowley Shock Trauma Center, Department of Surgical Critical Care, Baltimore, Maryland; University of Maryland School of Medicine, Department of Emergency Medicine, Baltimore, Maryland