[1] Univ Colorado, Sch Med, Dept Med, Aurora, CO USA
[2] Univ Colorado, Sch Med, Dept Emergency Med, Aurora, CO USA
[3] Univ Pittsburgh, Sch Med, Dept Crit Care Med, Pittsburgh, PA USA
[4] Univ Pittsburgh, Sch Med, Dept Emergency Med, Pittsburgh, PA USA
[5] Johns Hopkins Univ, Sch Med, Dept Med, Baltimore, MD 21205 USA
[6] Univ Hlth Network, Dept Med, Interdept Div Crit Care Med, Toronto, ON, Canada
[7] Univ Toronto, Sinai Hlth Syst, Toronto, ON, Canada
[8] Montefiore Hosp, Dept Med, New York, NY USA
[9] Intermt Med Ctr, Dept Med, Salt Lake City, UT USA
[10] Univ Utah, Salt Lake City, UT USA
[11] Univ Washington, Dept Med, Seattle, WA USA
[12] Massachusetts Gen Hosp, Biostat Ctr, Boston, MA 02114 USA
[13] Massachusetts Gen Hosp, Dept Med, Boston, MA 02114 USA
[14] Massachusetts Gen Hosp, PETAL Network Clin Coordinating Ctr, Boston, MA 02114 USA
[15] Brigham & Womens Hosp, Dept Emergency Med, Div Emergency Crit Care Med, 75 Francis St, Boston, MA 02115 USA
[16] Beth Israel Deaconess Med Ctr, Dept Anesthesia Crit Care & Pain Med, Boston, MA 02215 USA
[17] Cleveland Clin, Resp Inst, Dept Crit Care, Cleveland, OH 44106 USA
[18] Univ Michigan, Dept Med, Ann Arbor, MI 48109 USA
[19] Vet Affairs Ctr Clin Res, Ann Arbor, MI USA
[20] Oregon Hlth & Sci Univ, Dept Med, Portland, OR 97201 USA
[21] Univ Calif San Francisco, Dept Med, San Francisco, CA USA
[22] Univ Calif San Francisco, Dept Anesthesia, San Francisco, CA USA