Bailong Hu1, Haiyan Zhou2, Xiaohua Zou3. 1. Department of Anesthesiology, The Affiliated Hospital of Guizhou Medical University, No. 28 Guiyi Street, Yunyan District, 550004, Guiyang, China. 375896605@qq.com. 2. Department of Clinical Research Centre, The Affiliated Hospital of Guizhou Medical University, No. 28 Guiyi Street, Yunyan District, 550004, Guiyang, China. 3. Department of Anesthesiology, The Affiliated Hospital of Guizhou Medical University, No. 28 Guiyi Street, Yunyan District, 550004, Guiyang, China.