Hokkaido University - Department of Anesthesiology and Critical Care Medicine, Osaka Medical and Pharmaceutical University, Osaka Metropolitan University, Tsukuba Memorial Hospital, Keio University - School of Medicine, Tohoku University - Division of Emergency and Critical Care Medicine, JCHO (Japan Community Healthcare Organization), The University of Osaka, National Defense Medical College, Kameda Medical Center, Tokyo Medical and Dental University and Hokkaido University - Department of Anesthesiology and Critical Care Medicine