[1] Univ Utah Hlth, Dept Surg, Div Cardiothorac Surg, Salt Lake City, UT 84112 USA
[2] Univ Utah Hlth, Dept Emergency Med, Salt Lake City, UT 84112 USA
[3] Johns Hopkins Univ, Sch Med, Dept Neurol, Div Neurosci Crit Care, Baltimore, MD USA
[4] Johns Hopkins Univ, Sch Med, Dept Anesthesiol & Crit Care Med, Div Neurosci Crit Care, Baltimore, MD USA
[5] Johns Hopkins Univ, Sch Med, Dept Surg, Div Cardiac Surg, Baltimore, MD USA