Peripartum Events Associated with Severe Neurologic Morbidity and Mortality Among Acidemic Neonates

Purpose: To identify peripartum events that may predict the development of short-term neurologic morbidity and mortality among acidemic neonates.

Methods: Retrospective case-control study conducted at a single-teaching hospital on data from January 2010 to December 2015. The study cohort group included all acidemic neonates (cord artery pH ≤ 7.1) born at ≥ 34 weeks. Primary outcome was a composite including any of the following: neonatal encephalopathy, convulsions, intra-ventricular hemorrhage, or neonatal death. The study cohort was divided to the cases group, i.e., acidemic neonates who had any component of the primary outcome, and a control group, i.e., acidemic neonates who did not experience any component of the primary outcome.

Results: Of all 24,311 neonates born ≥ 34 weeks during the study period, 568 (2.3%) had a cord artery pH ≤ 7.1 and composed the cohort study group. Twenty-one (3.7%) neonates composed the cases group. Multivariate logistic regression analysis revealed that cases were significantly more likely to have experienced placental abruption (OR 18.78; 95% CI 5.57-63.26), born ≤ 2500 g (OR 13.58; 95% CI 3.70-49.90), have meconium (OR 3.80; 95% CI 1.20-11.98) and cord entanglement (OR 5.99; 95% CI 1.79-20.06). The probability for developing the composite outcome rose from 3.7% with isolated acidemia to 97% among neonates who had all these peripartum events combined with intrapartum fetal heart rate tracing category 2 or 3.

Conclusion: Neonatal acidemia carries a favorable outcome in the vast majority of cases. In association with particular antenatal and intrapartum events, the short-term outcome may be unfavorable.