Abstract: OBJECTIVE To explore the clinical characteristics of pulmonary infections in elderly patients in ICU of emergency department, analyze the related risk factors, and take the prevention countermeasures according to the high-risk factors.METHODS A total of 866 elderly patients who were treated in the ICU of emergency department from Feb 2013 to Feb 2016 were enrolled in the study.The clinical characteristics of pulmonary infections in the elderly patients and distribution of pathogens causing the infections were observed, the high-risk factors for the pulmonary infections in the elderly patients of ICU were analyzed by means of univariate analysis and multivariate analysis, and the statistical analysis was performed.RESULTS Cough and expectoration, chest tightness and shortness of breath were the major clinical manifestations of the patients with pulmonary infections.The X-ray examination showed that 98.88% of the patients had positive signs.The result of sputum culture indicated that the constituent ratios of Klebsiella pneumoniae and Pseudomonas aeruginosa were 39.32% and 30.34%, respectively.The result of the univariate analysis revealed that the incidence of pulmonary infections in the elderly patients was associated with the age, underlying diseases, and invasive operations (P＜0.05).The result of the multivariate logistic regression analysis showed that the no less than 80 years of age, no less than 2 types of underlying diseases, and invasive operations were the independent risk factors for the pulmonary infections. Among 89 patients with pulmonary infections, there were 48 (53.93%) patients whose symptoms completely disappeared, 17 (19.10%) patients whose symptoms relieved, 18 (20.22%) patients whose condition deteriorated, and 6 (6.74%) patients who died after the treatment.CONCLUSIONThe high-risk factors for the pulmonary infections in the elderly patients of ICU include the no less than 80 years of age, no less than 2 types of antibiotics, and invasive operations.It plays a positive role to develop the prevention measures according to the above high-risk factors so as to reduce the incidence of pulmonary infections.