1. Austrian Mountain Rescue Service, Vöcklabruck, Austria
2. Department of Anesthesiology and Intensive Care Medicine, Hospital Vöcklabruck, Vöcklabruck, Austria
3. Department of Anesthesiology and Intensive Care Medicine, Hospital Scheibbs, Scheibbs, Austria
4. Department of Anesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, Austria