[1] George Washington Univ, Sch Med & Hlth Sci, Dept Emergency Med, 2120 L St, Washington, DC 20037 USA
[2] George Washington Univ, Sch Med & Hlth Sci, Dept Med, Div Cardiol, Washington, DC 20037 USA
[3] Univ Maryland, Sch Med, Dept Emergency Med, Baltimore, MD USA
[4] Univ Maryland, R Adams Cowley Shock Trauma Ctr, Sch Med, Program Trauma, Baltimore, MD USA