1. Department of Anaesthesia, Centre of Head and Orthopaedics Copenhagen University Hospital Copenhagen Denmark
2. Department of Anesthesiology Copenhagen University Hospital, Herlev‐Gentofte Hospital Herlev Denmark
3. Department of Clinical Medicine Copenhagen University Copenhagen Denmark
4. Department of Anaesthesia University Hospital RWTH Aachen Germany
5. Department of Anesthesiology and Intensive Care Medicine University Hospital Bonn Bonn Germany
6. Department of Anaesthesia Nordsjællands Hospital Hillerød Denmark
7. Danish Air Ambulance Aarhus Denmark