Sepsis and Critical Illness in Babies > 34 Weeks Gestation

描述(申请人提供)：确诊的新生儿细菌感染发生率为每1000名活产中有1-5名。然而，在美国，大约10%-20%的新生儿做了“败血症检查”，4%-10%的新生儿接受了全身抗生素。教科书建议对有明确败血症、脑膜炎、休克或呼吸衰竭症状的婴儿进行抗生素治疗。它们没有为两类常见的足月或近期新生儿的评估和管理提供循证指导：1)没有症状或表现不明确的有细菌性感染(例如绒毛膜羊膜炎)母体风险因素的婴儿，以及2)呼吸窘迫的婴儿，大约2%-3%的足月和近期婴儿会发生呼吸窘迫。评估足月儿或近月儿的临床医生必须做出三个决定：1)是否进行实验室检查；2)是否使用抗生素治疗；3)是否将婴儿转移到三级护理中心。我们建议通过开发一种基于证据的方法来估计与这些决定相关的概率，从而改进对妊娠34周的新生儿细菌感染和/或危重疾病风险的评估和管理。我们将把特定孕龄的先验概率与母亲风险因素、临床体征和特定年龄的实验室结果的似然比结合起来。为了实现这一目标，我们有以下具体目标：1)进行嵌套病例对照研究，以量化母婴早发细菌感染的临床危险因素；2)进行一项回溯性横断面研究，利用来自14家医院的40,000多个CBC和血培养的数据，估计全血细胞计数(CBC，在这种情况下最常见的诊断试验)中早发性细菌感染的似然比；以及(3)进行嵌套病例对照研究，以开发一个量化模型来估计新生儿和GT的概率；=根据临床结果和包括动脉血气在内的实验室测试结果，妊娠34周发展为危重疾病(由危及生命的动脉血气结果定义)。为了实现这些目标，我们将分析1998年至2005年在北加州和波士顿的14家医院出生的34万名怀孕34周的新生儿的纸质和电子记录。我们的项目建立在Kaiser Permanente研究部、加州大学旧金山分校和哈佛新生儿医学计划的研究人员进行的大量开发工作的基础上。

DESCRIPTION (provided by applicant): Confirmed neonatal bacterial infections occur in 1-5 per 1000 live births. However, in the US about 10-20 percent of newborns have "sepsis work-ups" done, and 4-10 percent receives systemic antibiotics. Textbooks recommend antibiotic therapy for infants with definite signs of sepsis, meningitis, shock, or respiratory failure. They do not provide evidence-based guidance for the evaluation and management of two common groups of term or near-term newborns: 1) infants with maternal risk factors for bacterial infection (e.g., chorioamnionitis) with no symptoms or who have presentations that are considered equivocal, and 2) infants with respiratory distress, which occurs in approximately 2-3 percent of term and near-term infants. Clinicians evaluating term or near term infants must make 3 decisions: 1) whether to obtain laboratory tests; 2) whether to treat with antibiotics, and 3) whether to transfer the infant to a tertiary care center. We propose to improve the evaluation and management of newborns >= 34 weeks gestation at risk for bacterial infection and/or critical illness by developing an evidence-based approach to estimating probabilities relevant to each of these decisions. We will integrate gestational age-specific prior probabilities with likelihood ratios for maternal risk factors, clinical signs, and age-specific laboratory results. To achieve this goal, we have these Specific Aims: 1) To perform a nested case-control study to quantify maternal and infant clinical risk factors for early onset bacterial infection; 2) To perform a retrospective cross-sectional study to estimate likelihood ratios for early onset bacterial infection for components of the complete blood count (CBC, the most common diagnostic test in this setting), using data from more than 40,000 CBCs and blood cultures from 14 hospitals; and (3) To perform a nested case control study to develop a quantitative model to estimate the probability of newborns >= 34 weeks gestation developing a critical illness (defined by life-threatening arterial blood gas results) based on clinical findings and the results of laboratory tests, including arterial blood gases. To achieve these aims, we will analyze paper and electronic records from 340,000 newborns >= 34 weeks gestation born from 1998 to 2005 at 14 hospitals in Northern California and Boston. Our project builds on considerable development work conducted by investigators at Kaiser Permanente's Division of Research, the University of California, San Francisco, and the Harvard Newborn Medicine Program.