[1] Helsinki University Hospital,Department of Anesthesiology and Intensive Care Medicine
[2] Helsinki University Hospital,Department of Clinical Neurophysiology
[3] Helsinki University Hospital,Department of Anesthesia and Intensive Care Medicine
[4] Jorvi Hospital,Department of Anesthesia, Tampere University Hospital and Medical School
[5] University of Tampere,Department of Anesthesiology and Intensive Care Medicine
[6] Helsinki University Hospital,undefined
[7] Surgical Hospital,undefined
[8] VTT Technical Research Centre of Finland,undefined