1. Department of Anaesthesia and Intensive Care; Haukeland University Hospital; Bergen Norway
2. Department of Clinical Medicine; Faculty of Medicine and Dentistry; University of Bergen; Bergen Norway
3. Department of Anaesthesiology and Intensive Care; Stavanger University Hospital; Stavanger Norway
4. Department for Research and Development; The Norwegian Air Ambulance Foundation; Drøbak Norway
5. Norwegian National Advisory Unit on Trauma; Division of Emergencies and Critical Care; Oslo University Hospital; Oslo Norway