1 Department of Anesthesia, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minamikoshigaya, Koshigaya, Saitama, 343-8555, Japan. s-tomo@dokkyomed.ac.jp.
2 Department of Anesthesia, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minamikoshigaya, Koshigaya, Saitama, 343-8555, Japan.