1. Department of Anesthesia, Centre of Head and Orthopedics Copenhagen University Hospital, Rigshospitalet Copenhagen Denmark
2. Department of Anaesthesiology and Intensive Care Gødstrup Hospital Herning Denmark
3. Department of Clinical Medicine Aarhus University Aarhus Denmark
4. Department of Intensive Care Copenhagen University Hospital, Rigshospitalet Copenhagen Denmark
5. Department of Clinical Medicine University of Copenhagen Copenhagen Denmark
6. Department of Anaesthesiology and Intensive Care Horsens Hospital Horsens Denmark