1. Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, China
2. Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
3. Department of Critical Care Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
4. Medical Intensive Care Unit, Peking Union Medical College Hospital and Chinese Academy of Medical Sciences, Beijing, China