[1] Peking Univ, Dept Anesthesiol, Hosp 1, Beijing 100034, Peoples R China
[2] Chinese Acad Med Sci, Dept Anesthesiol, Cardiovasc Inst, Beijing 100037, Peoples R China
[3] Chinese Acad Med Sci, Fuwai Hosp, Beijing 100037, Peoples R China
[4] Peking Union Med Coll, Beijing 100021, Peoples R China
[5] Peking Univ, Dept Neurol, Hosp 1, Beijing 100034, Peoples R China