[1] Univ Klinikum Ulm, Klin Anasthesiol, D-89081 Ulm, Germany
[2] Univ Klinikum Ulm, Inst Anasthesiol Pathophysiol & Verfahrensentwick, Helmholtzstr 8-1, D-89081 Ulm, Germany
[3] CHU Angers, Med Intens Reanimat & Med Hyperbare, F-49933 Angers, France