[A prospective cohort study of risk factors for ventilator-associated pneumonia in intensive care unit]

To study the risk factors of ventilator-associated pneumonia (VAP) in intensive care unit (ICU), in order to offer basic epidemiological data for the prevention of VAP in ICU.

A prospective cohort study on VAP was carried out in intubated or tracheotomied patients in ICU of Fudan University Zhongshan Hospital from Dec.1999 to Feb. 2001. Single factor analysis and muti-variable logistic regression analysis were adopted to identify the possible risk factors of VAP.

(1) Ninety-eight patients were enrolled in this study, of which 52 were diagnosed as having VAP. The incidence of VAP was 53.1%. The incidence of VAP was 32.4 cases per 1000 intubation days. (2) Single factor analysis showed that history of chronic obstructive pulmonary emphysema, use of H2-receptor blocker, the days of antibiotic use, the types of antibiotics, enteral feeding, APACHEII scores, the duration of mechanic ventilation, pH of gastric juice, hypoalbuminemia, tracheotomy, reintubation, colonization of gram negative bacilli in oropharynx, and conscious disturbance were related to the occurrence of VAP. (3) Multi-variable logistic analysis showed statistical significance in combination of over two types of antibiotics (OR = 7.59, 95% CI 4.31 - 38.29), reintubation (OR = 4.73, 95% CI 2.33 - 11.67), APACHE II scores over 15 (OR = 2.02, 95% CI 1.59 - 26.74), pH of gastric juice over 4 (OR = 1.23, 95% CI 1.02 - 1.54) and prolongation of mechanic ventilation (OR = 1.15, 95% CI 1.01 - 3.75).

Various factors contributed to VAP in ICU. Further clinical trials are needed for evidence of the above-mentioned possible risk factors.