1. Oslo University Hospital Section of Drug Abuse Research, Department of Forensic Science, , P.O. Box 4950 Nydalen, N-0424 Oslo, Norway
2. Innlandet Hospital Trust Division of Elverum-Hamar, Department of Acute Medicine, , P.O. Box 104, N-2381 Brumunddal, Norway
3. Institute of Clinical Medicine, Department of Anesthesia and Intensive Care medicine, University of Oslo , P.O. Box 1171 Blindern, 0318 Oslo, Norway
4. Oslo University Hospital Division of Emergencies and Critical Care, Department of Anaesthesiology, , P.O. Box 4950, N-0424 Oslo, Norway
5. Oslo University Hospital Division of Emergencies and Critical Care, Department of Research & Development, , P.O. Box 4950, N-0424 Oslo, Norway
6. Oslo Metropolitan University Faculty of Health Sciences, Department of Nursing and Health Promotion, Acute and Critical Illness, , P.O. Box 4 St Olavs plass, N-0130 Oslo, Norway
7. Institute of Health and Society, Faculty of Medicine, University of Oslo Department of Public Health Science, , P.O. Box 1089 Blindern, 0318 Oslo, Norway