1. Department of Anesthesia; Klinikum am Bruderwald; Bamberg Germany
2. Department of Anesthesia; Kantonsspital Baden; Baden Switzerland
3. Department of Anesthesia; Töölö Hospital; University of Helsinki Central Hospital; Helsinki Finland
4. Department of Anesthesia; Jorvi Hospital; University of Helsinki Central Hospital; Helsinki Finland
5. Department of Anesthesia; University Hospital Aachen; Aachen Germany
6. Division of Preventive Medicine; University of Alberta; Edmonton Alberta Canada