冠状动脉旁路移植术后感染病原菌分布、耐药性及危险因素分析

Distribution characteristics and drug resistance of pathogenic bacteria and the risk factors of postoperative infection in patients underwent coronary artery bypass grafting

目的探讨冠状动脉旁路移植(CABG)术后感染的病原菌分布特征、耐药性及感染相关危险因素,为临床合理用药及预防术后感染提供指导。方法选择2017年3月至2019年3月于南阳市中心医院接受非体外循环下CABG治疗的962例冠状动脉粥样硬化性心脏病(CHD)患者为研究对象,根据术后是否发生感染将患者分为感染组和非感染组,对2组患者的临床资料进行比较,并采用单因素和多因素logistic回归模型分析患者术后感染的危险因素;采用分离培养法鉴定病原菌,采用K-B纸片琼脂扩散法评估病原菌的药物敏感性。结果962例CHD患者,CABG术后发生感染32例(感染组),未发生感染930例(非感染组),术后感染率为3.33%(32/962)。单因素分析结果显示,患者年龄、二次手术、术中出血量、手术时间、术前住院时间、胸腔引流时间、气管插管时间、导尿管留置时间、心功能纽约心脏学会(NYHA)分级、切口实施皮下连续缝合、预防性使用抗菌药物与CABG术后感染有关(P<0.05),而患者性别、并发症与CABG术后感染无关(P>0.05)。多元logistic回归分析结果显示,患者年龄≥60岁、术中出血量≥1200 mL、手术时间>5 h、胸腔引流时间≥3 d、二次手术、术前住院时间≥7 d、气管插管时间≥3 d、导尿管留置时间≥3 d、心功能NYHA分级≥Ⅲ级、切口实施皮下连续缝合、未预防性使用抗菌药物是CABG术后感染的独立危险因素(P<0.05)。32例感染患者共检出104株病原菌,其中革兰阴性菌60株(57.69%),革兰阳性菌33株(31.73%),真菌11株(10.58%)。病原菌前5位分别为铜绿假单胞菌、大肠埃希菌、金黄色葡萄球菌、肺炎克雷伯菌和粪肠球菌。铜绿假单胞菌、大肠埃希菌对氨苄西林的耐药性较高,而对亚胺培南、美罗培南较为敏感;肺炎克雷伯菌对头孢他啶、头孢曲松、头孢哌酮的耐药性较高,而对亚胺培南、美罗培南较为敏感。金黄色葡萄球菌、粪肠球菌对青霉素G的耐药性较高,而对万古霉素、利奈唑胺较为敏感;表皮葡萄球菌对四环素的耐药性较高,而对万古霉素、利奈唑胺较为敏感。结论患者年龄≥60岁、术中出血量≥1200 mL、手术时间>5 h、胸腔引流时间≥3 d、二次手术、术前住院时间≥7 d、气管插管时间≥3 d、导尿管留置时间≥3 d、心功能NYHA分级≥Ⅲ级、切口实施皮下连续缝合、未预防性使用抗菌药物是CABG术后感染的独立危险因素,临床应针对危险因素,采取相应的干预措施,以降低CABG术后感染率。CABG患者术后感染病原菌以革兰阴性菌居多,临床应根据药物敏感性试验结果,选择敏感抗菌药物治疗。

Objective To investigate the distribution characteristics and drug resistance of pathogenic bacteria and the risk factors of postoperative infection in patients underwent coronary artery bypass grafting(CABG),so as to provide the guidance for rational drug use and prevention of postoperative infection.Methods A total of 962 patients with coronary atherosclerotic heart disease(CHD)who received off-pump CABG in Nanyang Central Hospital from March 2017 to March 2019 were selected as the research subjects,and the patients were divided into the infection group and non-infection group according to the occurrence of infection.The clinical data of the patients were compared between the two groups,and the risk factors of postoperative infection were analyzed by univariate and multivariate logistic regression models.The pathogenic bacteria were identified by isolation culture method,and the drug sensitivity was evaluated by K-B disk agar diffusion method.Results Among the 962 patients with CHD,32 cases were infected after CABG(infection group),930 cases were not infected(non-infection group),the infection rate was 3.33%(32/962).Univariate analysis showed that the age,secondary operation,intraoperative bleeding,operation time,preoperative hospitalization time,chest drainage time,tracheal intubation time,indwelling catheter time,New York Heart Association(NYHA)classification,continuous subcutaneous suture,prophylactic use of antibiotics were associated with the infection after CABG(P<0.05).The gender and complications of the patients were not related to the infection after CABG(P>0.05).Multivariate logistic regression analysis showed that the patient′s age≥60 years old,intraoperative bleeding≥1200 mL,operation time>5 hours,chest drainage time≥3 days,secondary operation,preoperative hospitalization time≥7 days,tracheal intubation time≥3 days,indwelling catheter time≥3 days,NYHA grade≥Ⅲ,continuous subcutaneous suture and no prophylactic use of antibiotics were the independent risk factors for the infection after CABG(P<0.05).A total of 104 strains of pathogenic bacteria were detected in the 32 patients,including 60 strains of Gram-negative bacteria(57.69%),33 strains of Gram-positive bacteria(31.73%)and 11 strains of fungi(10.58%).The top five pathogens were Pseudomonas aeruginosa,Escherichia coli,Staphylococcus aureus,Klebsiella pneumoniae and Enterococcus faecalis in turn.The Pseudomonas aeruginosa and Escherichia coli were highly resistant to ampicillin,but they were sensitive to imipenem and meropenem.The Klebsiella pneumoniae was highly resistant to ceftazidime,ceftriaxone and cefoperazone,but it was sensitive to imipenem and meropenem.The Staphylococcus aureus and Enterococcus faecalis were more resistant to penicillin G,but they were sensitive to vancomycin and linezolid.The Staphylococcus epidermidis was highly resistant to tetracycline,but it was sensitive to vancomycin and linezolid.Conclusions The patient′s age≥60 years old,intraoperative bleeding≥1200 mL,operation time>5 hours,chest drainage time≥3 days,secondary operation,preoperative hospitalization time≥7 days,tracheal intubation time≥3 days,indwelling catheter time≥3 days,NYHA grade≥Ⅲ,continuous subcutaneous suture and no prophylactic use of antibiotics were the independent risk factors for the infection after CABG.In order to reduce the infection rate after CABG,the corresponding intervention measures should be taken according to the risk factors.Gram negative bacteria are the most common pathogens in the patients with infection after CABG.The sensitive antibiotics should be selected according to the results of drug sensitivity test.