[1] Univ Hosp Zurich, Inst intens Care Med, Zurich, Switzerland
[2] Univ Hosp Zurich, Dept Plast Surg & Hand Surg, Zurich, Switzerland
[3] Cantonal Hosp Winterthur, Ctr Intens Care Med, Winterthur, Switzerland
[4] Cantonal Hosp Winterthur, Intens Care Med, Brauerstr 15, CH-8401 Winterthur, Switzerland