1. Faculty of Medicine Institute of Clinical MedicineUniversity of Oslo Oslo Norway
2. Department of Acute Medicine Oslo University Hospital Oslo Norway
3. Department of Anesthesiology Oslo University Hospital Oslo Norway
4. Department of Anesthesiology Diakonhjemmet Hospital Oslo Norway
5. Department of Postoperative and Intensive care Oslo University Hospital Oslo Norway
6. Oslo Centre for Biostatistics and Epidemiology Oslo Norway
7. Prehospital Division Oslo University Hospital and Norwegian Air Ambulance Foundation Oslo Norway