512例心外科术后病原菌感染临床特征与危险因素分析

Analysis of clinical characteristics and risk factors in patients with infection after cardiac surgery

目的 分析心外科术后感染患者的临床特征、病原菌分布情况及发生感染的危险因素,为预防术后感染及制定临床防控措施提供参考依据。方法 选取2017-2021年于河南省南阳市第一人民医院心外科进行手术治疗的512例患者,其中35例发生术后感染,477例未发生感染。采集感染患者的分泌物进行细菌鉴定及药敏试验。感染组与未感染组患者的临床资料(包括年龄、性别、吸烟史、BMI、基础病情况、是否为二次手术、术前EF值、麻醉风险评分、气管插管时间、留置尿管时间、胸腔引流时间、呼吸机使用时间、输血量),进行单因素分析及多因素Logistic回归分析。结果 35例患者发生术后感染,感染率6.84%。15例患者年龄>70岁,24例于术后10 d内发生感染,11例于秋季发生感染。发生感染部位主要为呼吸道(37.14%)与表浅手术切口(25.71%)。本次研究中共检出35株病原菌。其中,革兰阴性菌18株,主要为肺炎克雷伯菌,革兰阳性菌15株,主要为金黄色葡萄球菌与表皮葡萄球菌。真菌2株。呼吸道感染病原菌主要为革兰阴性菌,表浅手术切口感染病原菌主要为革兰阳性菌。15株革兰阳性菌对青霉素耐药率较高,未发现对万古霉素、替考拉宁产生耐药的菌株。18株革兰阴性菌对哌拉西林的耐药率为83.33%,对亚胺培南、阿米卡星和美罗培南耐药率较低。对比感染组与未发生感染组患者的临床资料,结果显示,手术时间、吸烟史、合并糖尿病、二次手术、ASA分级、气管插管、胸腔引流时间、呼吸机使用时间、输血量差异有统计学意义(均P<0.05)。多因素分析显示,手术时间>6 h、合并糖尿病、二次手术、麻醉风险分级≥Ⅲ、气管插管时间>3 d、胸腔引流时间>5 d、呼吸机使用时间>5 d、输血量>400 ml是心外科术后发生感染的独立危险因素。结论 心外科术后感染部位主要为呼吸道与表浅手术切口,病原菌以肺炎克雷伯菌、金黄色葡萄球菌与表皮葡萄球菌为主。手术时间久、合并基础疾病、侵入性操作时间久、术中输血量大均容易引发心外科术后患者发生感染。

Objective To analyze the clinical characteristics, pathogen distribution and risk factors of infection in patients with postoperative infection in cardiac surgery, so as to provide reference for prevention of postoperative infection and development of clinical prevention and control measures. Methods From 2017 to 2021, 512 patients were selected for surgical treatment in the Department of Cardiology of the First People’s Hospital of Nanyang City, Henan Province, including 35 patients with postoperative infection and 477 patients without infection. The secretion of infected patients was collected for bacterial identification and drug sensitivity test. The clinical data(including age, sex, smoking history, BMI, basic diseases, whether it is a second operation, preoperative EF value, anesthesia risk score, tracheal intubation time, indwelling catheter time, thoracic drainage time, ventilator use time, blood transfusion volume) of patients in the infected group and the uninfected group were analyzed by single factor analysis and multiple factor logistic regression analysis. Results Postoperative infection occurred in 35 patients(6.84%). 15 patients were older than 70 years old, 24 patients were infected within 10 days after operation, and 11 patients were infected in autumn. The main infection sites were respiratory tract(37.14%) and superficial surgical incision(25.71%). A total of 35 pathogenic bacteria were detected in this study. Among them, there were 18 strains of gram-negative bacteria, mainly Klebsiella pneumoniae;15 strains of gram-positive bacteria, mainly Staphylococcus aureus and Staphylococcus epidermidis;and there were 2 strains of fungi. The main pathogens of respiratory tract infection were gram-negative bacteria, and the main pathogens of superficial surgical incision infection were gram-positive bacteria. The drug resistance rate of 15 Gram positive bacteria to penicillin was height, and no strains resistant to vancomycin and teicoplanin were found. The resistance rate of 18 strains of Gram negative bacteria to piperacillin was 83.33%, and the drug resistance rate to imipenem, amikacin and meropenem was low. The clinical data of the infected group and the non infected group were compared. The results showed that there were statistically significant differences in the comparison of the operation time, smoking history, diabetes, secondary operation, ASA classification, tracheal intubation, thoracic drainage time, ventilator use time, and blood transfusion volume(P<0.05). Multivariate analysis showed that operation time >6 h, combined with diabetes, second operation, anesthesia risk rating ≥ III, tracheal intubation time >3 d, thoracic drainage time >5 d, ventilator use time >5 d, and blood transfusion volume>400 ml were independent risk factors for infection after cardiac surgery. Conclusion The main infection sites after cardiac surgery were respiratory tract and superficial surgical incision. The main pathogens were K. pneumoniae,S. aureus and S. epidermidis. Long operation time, combined with basic diseases, long invasive operation time and large intraoperative blood transfusion are easy to cause infection in patients after cardiac surgery.