1. Department of Anaesthesiology and Intensive Care, Kuopio University Hospital, Kuopio, Finland.
2. Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.
3. CTU Bern, University of Bern, Bern, Switzerland.
4. Department of Neurosurgery, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
5. Department of Intensive Care Medicine, University of Bern, Bern, Switzerland.