重症监护病房机械通气相关性肺炎危险因素的前瞻性队列研究

目的　通过研究重症监护病房 (ICU)机械通气相关性肺炎 (VAP)的发病危险因素 ,为ICU的VAP防治提供基础的流行病学资料 ,为制定和采取预防控制措施提供科学依据。方法　以1999年 12月～ 2 0 0 1年 2月我院ICU行气管插管或气管切开患者为对象 ,采用前瞻性队列研究 ,作单因素和logistic回归分析 ,筛选VAP发病的可能危险因素。结果　研究期间共有 2 85例患者行人工气道机械通气 ,98例符合条件入选本研究 ,其中 5 2例发生VAP ,发生率为 5 3 1% ;以插管日计算 ,每 10 0 0个插管日发生 32 4例VAP。将 2 1项变量行单因素分析结果显示 ,COPD史 >15年、白蛋白 <30g/L、连续使用抗生素 >3d等 13项因素有统计学意义。logistic多因素分析显示 ,VAP的独立发病危险因素有 :同时使用 2种以上抗生素、重复气管插管、APACHEⅡ评分 >15分、胃液pH >4、机械通气时间延长。结论　ICU发生VAP是多种因素共同作用的结果。对已筛选的可能危险因素 ,需通过临床试验进一步证实。

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

OBJECTIVE: 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. METHODS: 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. RESULTS: (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). CONCLUSIONS: Various factors contributed to VAP in ICU. Further clinical trials are needed for evidence of the above-mentioned possible risk factors.