[1] Cangzhou Hosp Integrated TCM WM HEBEI, Dept Anesthesiol, Cangzhou, Heibei, Peoples R China
[2] Yangxin Peoples Hosp, Dept Anesthesiol, Huangshi, Hubei, Peoples R China
[3] Gen Hosp Western Theater Chinese Peoples Liberat A, Dept Mil Casualty Management, Sichuan, Chengdu, Peoples R China
[4] Cangzhou Hosp Integrated Chinese & Western Med, Dept Gynecol, Cangzhou, Heibei, Peoples R China
[5] Yanshan Peoples Hosp, Dept Cardiovasc Med, Cangzhou, Hebei, Peoples R China
[6] DaLian Med Ctr Women & Children, Dept Anesthesiol, Dalian 116011, Liaoning, Peoples R China