1 Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, 951-8510, Japan. yamatomo@med.niigata-u.ac.jp.
2 Division of Anesthesiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, 951-8510, Japan.
3 Division of Thoracic and Cardiovascular Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.