1 The Regional Centre for Emergency Medical Research and Development (RAKOS), Hillevågsveien 8, NO-4016 Stavanger, Norway; Department of Anaesthesiology and Intensive Care, Stavanger University Hospital, P. O. Box 8100, NO-4068 Stavanger, Norway. Electronic address: conrad.bjorshol@sus.no.
2 Oslo University Hospital, Oslo, Norway; University of Oslo, Oslo, Norway.