[1] Fudan Univ, Dept Anaesthesiol, Obstet & Gynecol Hosp, Shanghai 200090, Peoples R China
[2] Gen Hosp Guangzhou Mil Command PLA, Dept Anaesthesiol, Guangzhou 510010, Guangdong, Peoples R China
[3] Nanjing Matern & Child Care Hosp, Dept Anaesthesiol, Nanjing 210000, Jiangsu, Peoples R China
[4] Shanghai Jiao Tong Univ, Sch Med, Renji Hosp, Dept Anaesthesiol, Shanghai 200127, Peoples R China
[5] Tianjin Med Univ Gen Hosp, Dept Anaesthesiol, Tianjin 300052, Peoples R China
[6] Guangzhou Women & Childrens Med Ctr, Dept Anaesthesiol, Guangzhou 510623, Guangdong, Peoples R China
[7] Qingdao Univ, Dept Anaesthesiol, Affiliated Hosp, Qingdao 266071, Peoples R China
[8] Huazhong Univ Sci & Technol, Tongji Med Coll, Dept Anaesthesiol, Wuhan 430030, Hubei, Peoples R China
[9] Sun Yat Sen Univ, Sun Yat Sen Mem Hosp, Dept Anaesthesiol, Guangzhou 510120, Guangdong, Peoples R China
[10] Peking Univ, Hosp 1, Dept Anaesthesiol, Beijing 100034, Peoples R China