[1] Sichuan Univ, Dept Anesthesiol, West China Hosp, 37 Guoxue Alley, Chengdu, Sichuan, Peoples R China
[2] Sichuan Univ, Dept Pain, West China Hosp, 37 Guoxue Alley, Chengdu, Sichuan, Peoples R China
[3] Lab Anesthesia & Crit Care Med, Chengdu, Sichuan, Peoples R China