1. Department of Pulmonary and Critical Medicine, The First Clinical Medical College of Three Gorges University, Yichang Central People’s Hospital, Yi Chang, Hubei 443000, China
2. Department of Critical Care Medicine, The First Clinical Medical College of Three Gorges University, Yichang Central People’s Hospital, Yi Chang, Hubei 443000, China
3. Department of Intensive Care Unit, General Hospital of Southern Theatre Command of PLA, Guangzhou, Guangdong 510000, China