1. Department of Critical Care Medicine, West China Hospital of Sichuan University, 37 Guoxue Avenue, Chengdu 610041, China
2. Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China
3. Department of Critical Care Medicine, The First Hospital of Tsinghua University, Beijing 100016, China
4. Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China