1. Department of Emergency and Critical Care Medicine, Keio University School of Medicine, Shinanomachi 35, Shinjuku-ku, Tokyo 160-8582, Japan
2. Department of Emergency and Critical Care Medicine, Saiseikai Fukuoka General Hospital, 1-3-46 Tenjin, Chuo-ku, Fukuoka-shi, Fukuoka 810-0001, Japan