■脐带pH(UC-pH)水平是产时胎儿缺氧的重要客观指标,用于预测新生儿的发病率和死亡率。小于7.00的UC-pH值通常被定义为严重酸中毒的阈值。但是现有的证据是不同的,主要基于选定人群的UC-pH测量;因此,结果难以解释。
■在具有通用UC-pH测量的国家环境中,研究UC-pH水平与新生儿不良结局风险之间的关联。
■这个国家,以人群为基础的队列研究包括所有的活出生,单身人士,2012年1月1日至2018年12月31日在丹麦出生的无畸形足月婴儿。对2023年1月1日至2024年3月1日的数据进行了分析。
■脐带pH水平分为低于7.00、7.00至7.09、7.10至7.19和7.20至7.50(参照组)。
■主要结局是严重的新生儿不良结局:新生儿死亡,治疗性低温,机械通气,吸入一氧化氮治疗,或癫痫发作。次要结局是主要结局的各个组成部分,阿普加得分,呼吸结果,和低血糖。数据以95%CI的调整风险比(ARR)表示。
■在包括的340431名婴儿中,平均(SD)胎龄为39.9(1.6)周;平均(SD)出生体重为3561(480)g;男性占51.3%。在胎龄为40或41周的婴儿中,脐带pH值小于7.20的频率更高(31.6%-33.6%,而胎龄为39周时为18.2%-20.2%),男性婴儿(53.9%-55.4%,女性婴儿为44.6%-46.1%)。与pH参考组(253540中的576[0.2%])相比,UC-pH值低于7.00组的主要结局风险增加(1743人中的171人[9.8%]),7.00至7.09(11904中的101个[0.8%]),和7.10至7.19(73244中的259[0.4%])。观察到个体结果的可比模式,除了新生儿死亡,仅在UC-pH水平低于7.10的组中增加。当UC-pH值低于7.20时,持续气道正压通气治疗的风险增加,如果UC-pH值低于7.10,低血糖的风险为21.5%。
■在这项针对340431名新生儿的队列研究中,结果支持并扩展了之前的研究,这些研究表明,即使UC-pH水平高于7.00,出现不良结局的风险也较高.可以重新考虑更深入观察和治疗的阈值。
UNASSIGNED: Umbilical cord pH (UC-pH) level is an important objective indicator of intrapartum fetal hypoxia and is used to predict neonatal morbidity and mortality. A UC-pH value of less than 7.00 is often defined as a threshold for severe acidosis, but existing evidence is divergent and largely based on UC-pH measurements from selected populations; consequently, the results are challenging to interpret.
UNASSIGNED: To investigate the association between UC-pH levels and the risk of adverse neonatal outcomes in a national setting with universal UC-pH measurement.
UNASSIGNED: This national, population-based cohort study included all liveborn, singleton, full-term infants without malformations born in Denmark from January 1, 2012, to December 31, 2018. Data were analyzed from January 1, 2023, to March 1, 2024.
UNASSIGNED: Umbilical cord pH level categorized as less than 7.00, 7.00 to 7.09, 7.10 to 7.19 and 7.20 to 7.50 (reference group).
UNASSIGNED: The primary outcome was a composite of severe adverse neonatal outcomes: neonatal death, therapeutic hypothermia, mechanical ventilation, treatment with inhaled nitric oxide, or seizures. Secondary outcomes were individual components of the primary outcome, Apgar score, respiratory outcomes, and hypoglycemia. Data are presented as adjusted risk ratios (ARRs) with 95% CIs.
UNASSIGNED: Among the 340 431 infants included, mean (SD) gestational age was 39.9 (1.6) weeks; mean (SD) birth weight was 3561 (480) g; and 51.3% were male. Umbilical cord pH of less than 7.20 was observed more often among infants with a gestational age of 40 or 41 weeks (31.6%-33.6% compared with 18.2%-20.2% at a gestational age of 39 weeks) and among male infants (53.9%-55.4% vs 44.6%-46.1% among female infants). Compared with the pH reference group (576 of 253 540 [0.2%]), the risk for the primary outcome was increased for the groups with UC-pH levels of less than 7.00 (171 of 1743 [9.8%]), 7.00 to 7.09 (101 of 11 904 [0.8%]), and 7.10 to 7.19 (259 of 73 244 [0.4%]). Comparable patterns were observed for the individual outcomes, except for neonatal death, which was only increased in the group with UC-pH levels of less than 7.10. The risk of treatment with continuous positive airway pressure was increased when UC-pH levels were less than 7.20, and the risk of hypoglycemia was 21.5% if UC-pH levels were less than 7.10.
UNASSIGNED: In this cohort study of 340 431 newborn infants, results support and extend previous studies indicating a higher risk of adverse outcomes even at UC-pH levels above 7.00. The threshold for more intensive observation and treatment may be reconsidered.