呼吸机相关性肺炎患者病原菌分布及危险因素分析

目的 了解呼吸机相关性肺炎（ventilator-associated pneumonia, VAP）患者病原菌分布,并分析其危险因素,为呼吸机相关性肺炎防治提供依据。方法 收集2019年1月—2021年12月在遂宁市中心医院接受机械通气治疗患者,以拔管48 h内出现肺部感染性肺炎41例患者为VAP组,拔管48 h未内出现肺部感染性肺炎135例患者为非VAP组。收集两组患者的临床资料,了解VAP分布特点以及影响VAP发生的相关因素。结果 机械通气患者VAP发生率为23.30%（41/176）,从41例VAP患者痰培养液中分离出59株病原菌,其中革兰阴性菌37株（占62.71%）。单因素分析显示,VAP组侵入性操作、胃肠道反流及误吸、合并低蛋白血症、使用抑酸剂及采用平卧患者占比高于非VAP组,差异有统计学意义（P<0.05）,VAP组患者的抗菌药物使用时间、机械通气时间长于非VAP组,差异有统计学意义 （P<0.05）,年龄、急性生理学与慢性健康状况评分Ⅱ（acute physiology and chronic health evaluationⅡ,APACHEII）、插管次数均大于非VAP组,差异有统计学意义（P<0.05）。Logistic回归分析显示,合并低蛋白血症以及机械通气时间≥7 d、APACHEⅡ评分≥15分、抗菌药物使用时间≥6 d、插管次数≥2次是VAP发生的危险因素（P<0.05）。结论 VAP的病原菌主要为革兰阴性杆菌,患者合并症、机械通气/抗菌药物使用时间、插管次数、APACHEⅡ评分值为其高危因素。

Pathogenic bacteria and risk factors of ventilator-associated pneumonia

Objective To analyze the pathogenic bacteria distribution and risk factors of ventilator-associated pneumonia (VAP), and to provide basis for the prevention and treatment of VAP. Methods This study retrospectively reviewed 176 patients who underwent mechanical ventilation in Suining Central Hospital between January 2019 and December 2021. Among them, 41 patients who developed pneumonia induced by pulmonary infection within 48 h after extubation were included in VAP group, and 135 patients without pneumonia were included in non-VAP group. Clinical data of the two groups of patients was collected to understand the pathogenic bacteria distribution and influencing factors of VAP. Results Among the 176 patients included, 41 (23.30%) patients developed VAP, and 59 strains of pathogenic bacteria were isolated from sputum culture solution of the 41 patients. Among the strains obtained, there were 37 strains of Gram-negative bacteria, accounting for 62.71%. The proportions of patients with invasive procedures, gastrointestinal reflux and aspiration, hypoalbuminemia, use of antiacids and supine position in VAP group were higher than those in non-VAP group (P<0.05). The time of using antibacterial drugs and mechanical ventilation time in VAP group were longer than those in non-VAP group (P<0.05). Age, the acute physiology and chronic health evaluation II (APACHE II) scores, and intubation frequency in VAP group were higher than those in non-VAP group (P<0.05). Logistic regression analysis showed that hypoalbuminemia, mechanical ventilation time ≥7 d, APACHE II score ≥15, the time of using antibacterial drugs ≥6 d, and intubation frequency ≥twice were risk factors for VAP (P<0.05). Conclusions Gram-negative bacteria is the main pathogenic bacteria of VAP. Comorbidity, duration of mechanical ventilation, the time of using antibacterial drugs, intubation frequency and the APACHE II score are influencing factors, but there was no causal relationship.