1. Department of Anesthesiology, Guizhou Provincial People‘s Hospital, Guiyang, P. R. China
2. Department of Anesthesiology, Guizhou University People’s Hospital, , Guiyang, P. R. China
3. Department of Anesthesiology, West China Second University Hospital, Sichuan University, Chengdu, P. R. China
4. Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, P. R. China
5. Guizhou University Research Center for Analysis of Drugs and Metabolites, Guizhou University, Chengdu, P. R. China