1. Department of Anesthesiology and Intensive Care Medicine; University Medical Center Freiburg; Freiburg Germany
2. Institute of Technical Medicine (ITeM); Furtwangen University; Villingen-Schwenningen Germany
3. Klinik für Anästhesiologie, Operative Intensivmedizin, Rettungsmedizin, Schmerztherapie; Klinikum Herford; Herford Germany
4. Anesthesia and Intensive Care; Sahlgrenska University Hospital; Gothenburg Sweden