1. Department of Anesthesiology, The First Affiliated Hospital of Hebei North University, Zhangjiakou, Hebei 075000, China
2. Department of Geriatrics, The First Affiliated Hospital of Hebei North University, Zhangjiakou, Hebei 075000, China
3. Operating Room, The First Affiliated Hospital of Hebei North University, Zhangjiakou, Hebei 075000, China