Umbilical artery carbon dioxide decreases the risk for hypoxic-ischemic encephalopathy.

AIM: An accurate biomarker for metabolic acidosis at birth is needed. Our aims were to investigate the link between umbilical artery pCO2 and the risk for hypoxic-ischemic encephalopathy (HIE) and to compare false-negative screen results in newborn infants with HIE using three umbilical artery blood gas biomarkers. METHODS: From a cohort of newborn infants >/=35 weeks born in Ottawa, Canada, between January 2007 and December 2016, we highlighted those with HIE or who died. We compared the umbilical artery pCO2 for matched pH>mean versus matched pH /=16 mmol/L and neonatal eucapnic pH mean was 22%, compared to 78% for matched pH /=16 mmol/L. CONCLUSION: The rate of HIE or death is lower in newborn infants with higher pCO2 . Using neonatal eucapnic pH decreases the risk of missing newborn infants with HIE.