1. Pre-hospital division, Air ambulance department; Oslo university hospital; Oslo Norway
2. The Norwegian Air Ambulance Foundation; Drøbak Norway
3. Faculty of Health Sciences; University of Stavanger; Stavanger Norway
4. Department of Anaesthesia and Intensive Care, Medicine and Health; Linköping University; Linköping Sweden
5. Department of Anaesthesiology, Intensive Care and Pain Medicine; University of Helsinki and Helsinki University Hospital; Helsinki Finland
6. Department of Anaesthesia and Intensive Care Medicine; Landspitali University Hospital; Reykjavík Iceland
7. Department of Anaesthesia; Tampere University Hospital; Tampere Finland
8. Faculty of Medicine and Life Sciences; University of Tampere; Tampere Finland
9. Department of Intensive Care; Copenhagen University Hospital Rigshospitalet; Copenhagen Denmark