The significance of base deficit in acidemic term neonates

Preliminary case control study to establish the correlation between novel peroxidation biomarkers in cord serum and the severity of hypoxic ischemic encephalopathy

“…Metabolic acidosis defined as an arterial cord pH r 7.05 with or without venous pH r7.17 in conjunction with base excess of r10 mmol/L was present in 0.9% of deliveries, and in 0.1% there were transient neurologic sequel but unluckily no long term follow up was performed [23]. Other studies have tried to identify alterations of umbilical artery blood pH, base excess or even lactate with term infants at risk of morbidity [6,[24][25][26]. Notably, despite all these efforts the correlation between low umbilical artery pH, base excess or even lactate and neurological outcome has not been clearly established and most term neonates with low pH, elevated base excess, or even elevated lactate develop normally [27,28].…”

Perinatal inflammation/infection and its association with correction of metabolic acidosis in hypoxic-ischemic encephalopathy

“…Recent research examining the independent effect of umbilical arterial base deficit and pH at delivery with neonatal neurologic morbidity suggest that worse outcomes with greater base deficit simply reflect a relationship with a decreased pH such that the prognostic significance attached independently to base deficit among acidemic neonates may be questionable. 15 At the same time, it would support the thesis that either clinical or histologic chorioamnionitis appear to impair correction of metabolic acidosis.…”

Determination of base excess in umbilical cord blood at birth: accessory or excess?

“…As BD is calculated from pH and pCO 2 values, BD is not an independent parameter and a negative linear relation exists to pH (Fig. 1), illustrating the statement by Knutzen et al (9) that a high BD ecf in cases of low pH simply reflect a greater degree of acidemia. However, the cord artery BD value is valuable for the neonatologist in assessment and management of the asphyxiated newborn and therefore cannot be omitted from the panel of cord blood acid-base parameters.…”

“…It is unanimously accepted that it is the metabolic component of acidemia that associates with neonatal morbidity, but in this issue of the Journal Knutzen et al (9) challenge the concept that determination of BD in umbilical cord blood adds to pH in the evaluation and management of acidemic newborns. In a study of 8797 term, singleton, non-anomalous neonates, where 520 were acidemic (pH <7.1) and 84 were severely acidemic (pH <7.0), they found in associations with Apgar score <7 at 5 minutes, hypoxic-ischemic encephalopathy Sarnat stage 2 or 3, neonatal intensive care unit admission, and a composite adverse outcome parameter, that adding BD ecf to pH did not improve the prediction of adverse outcomes once pH was taken into account.…”