1. Department of Anesthesiology and Pain Medicine, Inselspital, University Hospital Bern, University of Bern, 3010 Bern, Switzerland
2. Limmat Cleft- and Craniofacial Center Zurich, 8005 Zurich, Switzerland
3. Department of Anesthesiology, Lindenhof Hospital Bern, 3012 Bern, Switzerland
4. Department of Intensive Care Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland