Department of Anaesthesiology, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Goethe University Frankfurt, Frankfurt, Germany. Department of Anaesthesiology, Intensive Care Medicine and Pain Medicine, Medical University Vienna, Vienna, Austria. Department of Anaesthesiology, Hospital Universitari del Mar de Barcelona, Barcelona, Spain. Anesthesiology, Critical Care and Emergency Department, University Hospital Angers, CHU Angers, Angers, France. Division of General Anaesthesiology, Emergency- and Intensive Care Medicine, Medical University of Graz, Graz, Austria. Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria. The Royal Marsden NHS Foundation Trust, London, UK. Department of Anaesthesiology, Klinik Floridsdorf - Wiener Gesundheitsverbund, Vienna, Austria. Department of Gastroenterology and Hepatology, Klinik Hietzing - Wiener Gesundheitsverbund, Vienna, Austria. Department of Anaesthesiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland. Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Wuerzburg, Wuerzburg, Germany.