[1] Univ Klinikum Schleswig Holstein, Klin Anasthesiol & Operat Intens Med, D-24105 Kiel, Germany
[2] Univ Gottingen, Univ Klinikum, Klin Anaesthesiol Rettungs & Intens Med, D-3400 Gottingen, Germany
[3] Heidelberg Univ, Univ Klinikum Heidelberg, Anasthesiol Klin, Heidelberg, Germany
[4] Med Univ Innsbruck, Univ Klin Anaesthesie & Allgemeine Intens Med, Innsbruck, Austria
[5] Klinikum Saarbrucken gGmbH, Anasthesiol Klin, Saarbrucken, Germany