极低、超低体重早产儿医院感染变化及其危险因素分析*

目的 探讨5年间极低、超低体重早产儿医院感染变化趋势及危险因素。方法 选取2014年1月— 2018年12月江门市中心医院新生儿重症监护室的极低、超低体重早产儿303例患儿资料进行回顾性分析，比较5年 间早产儿医院感染例数率、例次率及感染疾病发病率、感染组与非感染组临床特征、病原菌和耐药菌的变化并分 析其危险因素。结果 5年间早产儿医院感染例数率、例次率及感染疾病发病率比较，差异无统计学意义（P > 0.05）。发生医院感染的早产儿5年间临床特征比较，肠外营养（PN）时间和外周中心静脉导管（PICC）置管时间， 2017年组、2018年组均比2014年组、2015年组、2016年组延长（P <0.05）；生后3代头孢菌素应用率，2017年组 比2014年组增多（P<0.05），2018年组比2014年组、2015年组和2016年组增多（P<0.05）。未发生医院感染的早产 儿5年间临床特征比较，胎龄，2016年组比2015年组、2017年组减小（P<0.05），2018年组比2017年组减小（P < 0.05）；气管插管时间，2016 年组比其他4 年组延长（P <0.05）；有创呼吸机应用率，2016 年组高于2014 年组、 2015年组、2018年组（P <0.05）；生后3代头孢菌素应用率，2016年组、2017年组、2018年组比2014年组、2015 年组增多（P <0.05）；脐静脉置管（UVC）率，2016年组比2014年组、2017年组、2018年组增多（P <0.05）。5年间 早产儿医院感染部分病原菌仍以肺炎克雷伯杆菌及大肠埃希氏菌居多，病原菌构成比差异有统计学意义的是人葡 萄球菌，2018年比前4年增多（P <0.05）。感染组与非感染组早产儿比较，性别、出生体重、胎龄、气管插管（有 创呼吸机）、UVC、PICC、生后3代头孢菌素应用差异均有统计学意义（P <0.05）。感染组气管插管时间、PICC 时间、PN时间和住院时间均高于非感染组（P <0.05），白蛋白水平低于非感染组（P <0.05）。logistic回归分析结果， 出生体重<1000 g［O^R=2.539（95% CI：1.101，5.856）］、气管插管［O^R=1.952（95% CI：1.056，3.610）］、气管插管 时间［O^R=1.089（95% CI：1.019，1.164）］和PICC时间［O^R=1.034（95% CI：1.011，1.057）］均是极低、超低体重早产 儿发生医院感染的独立危险因素。结论 近年早产儿医院感染率并无减少；胎龄更小、有创通气支持减少、插管 时间减少是近两年未发生医院感染早产儿的特征；但3代头孢菌素应用率上升。提高出生体重、减少气管插管、 缩短气管插管时间和PICC时间可降低早产儿医院感染发生率。

Analysis of nosocomial infection changes and risk factors of very low birth weight and extremely low birth weight preterm infants in five years*

Objective To explore the changing trends and risk factors of nosocomial infection of very low birth weight and extremely low birth weight preterm infants in five years. Methods There were 303 cases of very low birth weight and extremely low birth weight preterm infants admitted to the neonatal intensive care unit of Affiliated Jiangmen Hospital of Sun Yat-Sen University, Guangdong Province, from January 2014 to December 2018. The infection rate, infection times rate, incidence of infectious diseases, clinical characteristics of the infected and non-infected groups, changes of pathogens and drug-resistance bacteria, and risk factors were retrospectively analyzed. Results There was no statistical difference in the infection rate, infection times rate, and incidence of infectious disease of preterm infants in five years (P < 0.05). Comparison of clinical characteristics of preterm infants with nosocomial infection in five years: parenteral nutrition (PN) time and peripherally inserted central catheter (PICC) time in the last two years were longer than in the first three years (P < 0.05); the application rate of the third generation cephalosporin after birth in 2017 was higher than that in 2014 (P < 0.05), and the rate in 2018 was higher than those in 2014, 2015 and 2016 (P < 0.05). Comparison of clinical characteristics of preterm infants without nosocomial infection: Gestational age in 2016 was smaller than those in 2015 and 2017 (P < 0.05), and that in 2018 was smaller than that in 2017 (P < 0.05); the rate of invasive ventilation in 2016 was higher than those in 2014, 2015 and 2018 (P < 0.05); intubation time in 2016 was longer than the other four years (P < 0.05); the application rate of the third generation cephalosporin after birth in the last three years were higher than those in the first two years (P < 0.05). Compared to 2014, 2017, and 2018, the rate of umbilical venous catheter (UVC) in 2016 had an increase (P < 0.05). In the past five years, Klebsiella pneumoniae and Escherichia coli were still the most common pathogens of nosocomial infection in preterm infants. The proportion of pathogens was statistical difference in human Staphylococcus, which increased in 2018 compared with the previous four years (P < 0.05). Comparison between the infected group and the non-infected group showed statistical differences in terms of gender, birth weight, gestational age, tracheal intubation, UVC, PICC and application of the third generation cephalosporin after birth (P < 0.05). Tracheal intubation time, PICC time, PN and hospitalization time in the infected group were all longer than those in the non-infected group (P < 0.05), and albumin level was lower than that in the non-infected group (P < 0.05). Logistic regression analysis showed that birth weight lower than 1000 g, tracheal intubation, tracheal intubation time and PICC time were independent risk factors for nosocomial infection in very low birth weight and extremely low birth weight preterm infants. Conclusion The infection rate of preterm infants in hospitals has not decreased in recent years. Less gestational age, reduced invasive ventilation support, and shorter tracheal intubation time were the characteristics of preterm infants without nosocomial infection in the last two years. But application rate of the third generation cephalosporin increased. Improving the birth weight, reducing tracheal intubation, shortening the time of tracheal intubation, and PICC can reduce the incidence of nosocomial infection in preterm infants.