重症监护病房早发与晚发呼吸机相关性肺炎病原体耐药性差异

目的了解某院重症监护病房（ICU）呼吸机相关性肺炎(VAP)发生及病原菌耐药情况。方法对该院ICU 2011年1月-2012年12月间使用机械通气时间＞48 h的住院患者VAP发生情况进行调查，比较早发VAP（E VAP，机械通气时间≤4 d）和晚发VAP（L VAP，机械通气时间＞4 d）病原菌及其耐药情况。结果共调查患者176例，VAP发生率为44.32%（78例）；随着呼吸机使用时间的延长，VAP的发生率逐渐增高（χ2=52.561，P＜0.001）。L VAP发生率为58.33%（70/120），显著高于E VAP的14.29%（8/56）,差异有统计学意义（χ2=30.02，P＜0.001）。分离病原体178株，其中革兰阴性（G-）菌104株（58.43%），革兰阳性（G+）菌46株（25.84%）、真菌28株（15.73%）；分离多重耐药菌/泛耐药菌97株（54.49%）。L VAP患者多重耐药菌/泛耐药菌分离率（58.86%，93株）显著高于E VAP患者（20.00%，4株），L VAP患者分离的主要病原菌耐药率显著高于E VAP患者（均P＜0.05））。真菌感染仅发生在L VAP患者，其总体耐药率为12.14%。结论呼吸机使用时间的延长，可增加VAP的发生率；L VAP患者感染的病原体耐药率高。

Difference in drug resistance of pathogens causing early and late onset ventilator associated pneumonia in an intensive care unit

ObjectiveTo study the incidence of ventilator associated pneumonia(VAP)and antimicrobial resistance of pathogens in an intensive care unit(ICU).MethodsThe occurrence of VAP in hospitalized patients with mechanical ventilation >48 hours between January 2011 and December 2012 were investigated, species and antimicrobial resistance of pathogens causing early onset VAP (E VAP, mechanical ventilation≤4 d）and late onset VAP（L VAP，mechanical ventilation ＞4 d） were compared.ResultsA total of 176 patients were investigated,incidence of VAP was 44.32%（78 cases）；With the prolongation of mechical ventilation，incidence of VAP increased gradually (χ2=52.561，P＜0.001）.The incidence of L VAP was significantly higher than E VAP (58.33% ［70/120］ vs 14.29% ［8/56］）（χ2=30.02，P＜0.001）.A total of 178 pathogens were isolated, gram negative bacteria,gram positive bacteria and fungi were 104（58.43%）,46（25.84%）,and 28（15.73%） isolates respectively； 97(54.49%) multidrug resistance/pandrug resistance organisms (MDRO) were isolated. MDRO isolation rate in L VAP patients was higher than E VAP patients（［58.86%，n=93］ vs ［20.00%，n=4］）,resistance rate of major pathogens causing L VAP was significantly higher than E VAP patients(all P<0.05).Fungi infection only occurred in L VAP patients, the total antimicrobial resistance rate was 12.14%.ConclusionThe prolongation of mechanical ventilation can increase the incidence of VAP, and resistance rate of pathogen in L VAP is high.