Depressed Apgar scores, acid-base status, and neurologic outcome.

OBJECTIVE

Our purpose was to determine the acid-base status of neonates with an Apgar score < or = 3 at 5 minutes and to ascertain whether accompanying acidemia is an important predictor of immediate newborn morbidity and long-term neurologic development.

STUDY

DESIGN

From January 1984 through December 1991 there were 28 newborns with gestational age > or = 34 weeks or birth weight > or = 2000 gm in whom the Apgar score at 5 minutes was < or = 3 and for whom umbilical cord arterial blood gas measurements were retrievable from the perinatal database. The neonates were grouped according to whether the immediate newborn course was complicated (n = 16) or uncomplicated (n = 12). Analysis of variables between these two groups and between those neonates in the complicated group who were later assessed to be developmentally normal (n = 6) or to have cerebral palsy (n = 6) was performed by Fisher's exact test, unpaired Student t test, Mann-Whitney U test, analysis of variance, or multiple logistic regression.

RESULTS

Seventeen of 28 (60.7%) neonates with an Apgar score of < or = 3 at 5 minutes had an umbilical cord arterial pH > 7.00, and in 15 (53.6%) cases the pH was > 7.10. Neonates with a complicated newborn course had a significantly lower mean pH (6.94 +/- 0.19 vs 7.14 +/- 0.11, p < 0.01) and a significantly greater mean base deficit (14.8 +/- 6.3 mmol/L vs 6.4 +/- 4.0 mmol/L, p < 0.001). However, within this group there were no differences in umbilical cord arterial blood gas measurements between those children who were subsequently normal versus those with cerebral palsy. Multiple logistic regression analysis could not identify any newborn morbidity predictive of long-term neurologic development in those neonates with a complicated newborn course.

CONCLUSIONS

Neonates with an Apgar score < or = 3 at 5 minutes and a complicated newborn course were more likely to be delivered by cesarean section for fetal heart rate abnormalities and to have lower umbilical cord arterial pH measurements and higher base deficit values than did their counterparts with an uncomplicated newborn course. No neonatal variable, however, was predictive of chronic neurologic disability within the group of neonates with a complicated newborn course.