Lactate and pH values in newborns with a history of acute fetal distress.

Background: Acute fetal distress (AFD) is a condition that requires timely diagnosis because it generates hypoxia, acidosis, and even intrauterine death. This study aimed to determine lactate and pH values in the umbilical cord in full-term newborns (NBs) with a history of AFD.

Methods: We conducted a cross-sectional study in full-term NBs of mothers with at least one perinatal, neonatal, or gasometric AFD antecedent. Neonatal morbidity was considered: if 1-min Apgar ≤ 6, or advanced neonatal maneuvers, or neonatal intensive care unit (NICU) admissions were necessary. The cutoff points were lactate > 4mmol/L and pH < 7.2.

Results: Of 66 NBs, 33.3% of mothers presented at least one antecedent for developing AFD; 22.7% presented hypertensive pregnancy disease, 13.6% oligohydramnios, and 63.6% other factors. Perinatally, 28.7% required advanced neonatal resuscitation maneuvers and 7.5% admission to the NICU. In the gasometry, the lactate and pH values for the neonatal morbidity of the NBs' group were 4.726 ± 1.401 and 7.293 ± 0.056, respectively, versus 2.240 ± 0.318 and 7.359 ± 0.022 (p < 0.05) for the group without associated neonatal morbidity.

Conclusions: Lactate values in the umbilical cord increased by 25%, and pH decreased by one percent in NBs with a history of AFD and associated morbidity.