[1] Univ Washington Med, Dept Anesthesiol & Pain Med, Seattle, WA USA
[2] Univ Colorado, Sch Med, Dept Surg, Anschutz Med Campus, Aurora, CO USA
[3] Denver Hlth Med Ctr, Trauma Surg, Denver, CO USA
[4] Univ Colorado, Sch Publ Hlth, Anschutz Med Campus, Aurora, CO USA
[5] Vitalant Res Inst, Denver, CO USA
[6] Univ Maryland, Sch Med, Dept Surg, Baltimore, MD USA
[7] Univ Colorado, Sch Med, Dept Pediat, Anschutz Med Campus, Aurora, CO USA
[8] Vitalant Res Inst, 717 Yosemite St, Denver, CO 80230 USA