Xu Yan, Zhang Le-jia, Ge Hai-yan, Wang Dan-hua
Department of Pediatrics, Peking Union Medical College (PUMC) Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
Zhonghua Er Ke Za Zhi. 2007 Jun;45(6):437-41.
Nosocomial infections (NIs) have become a matter of major concern in neonatal intensive care units (NICU). The objectives of this study were to investigate the incidence of nosocomial infections of newborn infants in NICU and to explore the risk factors and strategies of infection control.
The study enrolled 638 hospitalized newborn infants from Apr 2003 to Dec 2004. The clinical data, such as the clinical manifestation, the condition of colonized bacteria, were collected and analyzed by using SPSS software.
There were 88 times of nosocomial infections in 74 newborn infants. The overall incidence of nosocomial infections was 11.6%. The mean duration from admission to first episode of NI was 7.98 +/- 4.58 days. The incidence density was 14.9 per 1000 NICU patient-days. Catheter-correlated hematogenous infection rate was 18 per 1000 umbilical or central line-days; the ventilator-associated nosocomial pneumonia rate was 63.3 per 1000 ventilator days. The smaller the gestational age and the lower the birth weight, the higher the incidences of nosocomial infection. The duration of hospitalization was longer in these infected infants than those non-infected infants. Univariate analysis indicated that gestational age < or = 32 W, the parenteral nutrition, birth weight < or = 1500 g and mechanical ventilation, apnea, small for gestational age infant, central venous catheter (P < 0.05) were risk factors for NIs. Multivariate analysis identified 3 independent risk factions: the parenteral nutrition ([OR] = 7.185 [95% CI, 3.399 - 15.188]), birth weight < or = 1500 g ([OR] = 3.310 [95% CI, 1.100 - 9.963]) and mechanical ventilation ([OR] = 2.527 [95% CI, 1.092 - 5.850]). The most common infection was pneumonia (45.4%). The mortality rate of nosocomial infections was 4.1%. Bacterial surveillance was examined by nasopharyngeal and rectal swab culture immediately on hospital admission and then once a week. The incidence rate of NIs was 24.8% in patients whose nasopharyngeal and rectal swab culture indicated bacterial colonization, and 1.9% in patients without bacterial colonization (chi(2) = 79.7, P < 0.001).
It is important to identify the high risk factors for nosocomial infections in newborn infants in NICU. Reducing the duration of the parenteral nutrition and the virulence manipulation as far as possible and getting the message of individual bacterial colonization in NICU may be conducive to decrease of the incidence of nosocomial infections and provide reference for rational clinical drug administration.
医院感染（NI）已成为新生儿重症监护病房（NICU）中备受关注的问题。本研究的目的是调查NICU中新生儿医院感染的发生率，并探讨感染的危险因素及控制策略。
本研究纳入了2003年4月至2004年12月期间住院的638例新生儿。收集其临床表现、定植菌情况等临床资料，并使用SPSS软件进行分析。
74例新生儿发生医院感染88次。医院感染的总体发生率为11.6%。从入院到首次发生NI的平均时间为7.98±4.58天。发病密度为每1000个NICU患者日14.9次。导管相关血行感染率为每1000个脐静脉或中心静脉置管日18次；呼吸机相关性医院肺炎率为每1000个呼吸机日63.3次。胎龄越小、出生体重越低，医院感染的发生率越高。这些感染婴儿的住院时间比未感染婴儿更长。单因素分析表明，胎龄≤32周、肠外营养、出生体重≤1500g、机械通气、呼吸暂停、小于胎龄儿、中心静脉导管（P<0.05）是NI的危险因素。多因素分析确定了3个独立危险因素：肠外营养（[OR]=7.185[95%CI，3.399-15.188]）、出生体重≤1500g（[OR]=3.310[95%CI，1.100-9.963]）和机械通气（[OR]=2.527[95%CI，1.092-5.850]）。最常见的感染是肺炎（45.4%）。医院感染的死亡率为4.1%。入院时立即通过鼻咽和直肠拭子培养进行细菌监测，然后每周进行一次。鼻咽和直肠拭子培养显示有细菌定植的患者中NI发生率为24.8%，无细菌定植的患者中NI发生率为1.9%（χ²=79.7，P<0.001）。
识别NICU中新生儿医院感染的高危因素很重要。尽可能缩短肠外营养的时间并减少毒力操作，了解NICU中个体细菌定植情况，可能有助于降低医院感染的发生率，并为临床合理用药提供参考。
