[1] Shandong Univ, Dept Resp & Crit Care Med, Shandong Prov Hosp, Jinan, Peoples R China
[2] Shandong Univ, Cheeloo Coll Med, Jinan, Peoples R China
[3] People Hosp Dongying Dist, Dept Geriatr, Dongying, Peoples R China
[4] Shandong First Med Univ, Dept Resp & Crit Care Med, Shandong Prov Hosp, Jinan, Peoples R China
[5] Shandong Prov Third Hosp, Dept Crit Care Med, Jinan, Peoples R China
[6] Beijing Hosp, Dept Resp & Crit Care Med, Beijing, Peoples R China
[7] Chinese Acad Med Sci & Peking Union Med Coll, Peking Union Med Coll, Grad Sch, Beijing, Peoples R China
[8] Shandong Univ Tradit Chinese Med, Coll Clin Med 1, Jinan, Peoples R China