pH, base deficit or lactate. Which is better for predicting neonatal morbidity?

Area of Science:

• Neonatalogy
• Perinatal Medicine
• Clinical Chemistry

Background:

• Neonatal acidemia is a critical condition requiring accurate assessment.
• Umbilical arterial cord gas analysis is routinely used to evaluate fetal well-being.
• Parameters like pH, base deficit (BD), and lactate are analyzed, but their comparative predictive values for neonatal outcomes are debated.

Purpose of the Study:

• To compare the predictive ability of umbilical arterial pH, base deficit (BD), and lactate for neonatal morbidity in term infants with acidemia.
• To determine if lactate or BD offer superior prediction compared to pH alone.

Main Methods:

• Retrospective cohort study of 466 term, non-anomalous neonates with acidemia (umbilical arterial pH ≤ 7.1).
• Comparison of predictive abilities for composite neurological and systemic morbidity using receiver operator characteristic (ROC) curves.
• Estimation of optimal cutoff values using the Youden Index.

Main Results:

• pH, BD, and lactate demonstrated similar predictive abilities for neurological (AUCs: 0.81, 0.78, 0.83) and systemic morbidity (AUCs: 0.77, 0.82, 0.82).
• Combined analysis of pH and lactate or pH and BD did not significantly improve predictive accuracy over pH alone.
• Umbilical arterial lactate showed comparable predictive value to BD.

Conclusions:

• Umbilical arterial pH, BD, and lactate possess similar predictive capabilities for adverse neonatal outcomes in acidemic neonates.
• Lactate can be considered a viable alternative to BD for assessing the metabolic component of acidemia.
• Neither BD nor lactate, when used with pH, enhanced the prediction of short-term neonatal outcomes beyond pH alone.