Affiliation: | (1) Department of Anesthesiology, University Hospital of Oulu, Finland;(2) Department of Physiology, University of Oulu, Finland;(3) Department of Surgery, University Hospital of Oulu, Finland;(4) Present address: Department of Anesthesiology, University Central Hospital of Oulu, Kajaanintie 50, 90220 Oulu, Finland |