[1] Hainan Gen Hosp, Dept Pulm & Crit Care Med, Haikou, Peoples R China
[2] Hainan Med Univ, Affiliated Hainan Hosp, Dept Pulm & Crit Care Med, Haikou, Peoples R China
[3] Cent South Univ, Xiangya Hosp, Dept Oncol, Changsha, Peoples R China
[4] Hainan Med Univ, Key Lab Emergency & Trauma, Minist Educ, Haikou 571199, Peoples R China
[5] Cent South Univ, Xiangya Hosp, Dept Resp Med, Dept Resp & Crit Care Med, Changsha 410008, Hunan, Peoples R China
[6] Cent South Univ, Xiangya Hosp, Natl Clin Res Ctr Geriatr Disorders, Changsha 410008, Hunan, Peoples R China