[1] Duke Univ, Med Ctr, Dept Anesthesiol, Durham, NC 27710 USA
[2] Univ Pittsburgh, Sch Med, Dept Crit Care Med, Safar Ctr Resuscitat Res, Pittsburgh, PA 15260 USA
[3] Univ Med Ctr Utrecht, Afdeling Anesthesiol, NL-3508 GA Utrecht, Netherlands
[4] Lund Univ, Dept Clin Sci, S-22185 Lund, Sweden
[5] Radboud Univ Nijmegen, Dept ICU, Med Ctr, NL-6525 ED Nijmegen, Netherlands
[6] Med Univ Vienna, Dept Emergency Med, A-1090 Vienna, Austria
[7] Univ N Carolina, Dept Emergency Med, Chapel Hill, NC 27599 USA
[8] NIOSH, Ctr Dis Control, Washington, DC USA
[9] Univ Pittsburgh, Childrens Hosp Pittsburgh, Med Ctr, Pittsburgh, PA 15213 USA
[10] Skane Univ Hosp, Dept Intens & Perioperat Care, Lund, Sweden
[11] Childrens Hosp Philadelphia, Philadelphia, PA 19104 USA
[12] Maatschappij Redding Drenkelingen, Amsterdam, Netherlands