1. Department of Intensive Care, University Hospital of North Norway , P.O. Box 100, 9038 Tromsø , Norway
2. Western Norway University of Applied Sciences , P.O. Box 7800, 5020 Bergen , Norway
3. Department of Heart Disease, Haukeland University Hospital , P.O. Box 1400, 5021 Bergen , Norway
4. Department of Clinical Science, Faculty of Medicine, University of Bergen , Bergen , Norway
5. Department of Global Public Health and Primary Care, University of Bergen , Bergen , Norway
6. Centre for Clinical Research, Haukeland University Hospital , Bergen , Norway