Aims: To describe the base deficit (BD) values and the rate of postnatal recovery of the BD of infants with hypoxic ischemic encephalopathy due to intrapartum asphyxia; and to explore the relationships between the rate of recovery of BD, severe adverse outcome and different time patterns (acute total vs prolonged partial) of asphyxia.
Methods: Clinical and laboratory data were collected from the neonatal period (n = 244) and outcome data to a minimal age of 1 y (n = 218). Rates of recovery of BD were described in four 60 min blocks of time. The values of rate of recovery were compared between the outcome groups, ignoring correlation structure within subjects and with adjustment by the generalized estimating equations method.
Results: The BD normalized within 4 h of birth in all but 9 of 244 infants. The rates of recovery of BD in infants with good and severe adverse outcome respectively were 0.11 [95% confidence interval (95% CI) 0.07, 0.14] and 0.09 (95% CI 0.07, 0.12) mmol l(-1) min(-1) over the first 4 h after birth. The rates of recovery were similar with or without buffer therapy, and after acute near-total and prolonged partial asphyxia.
Conclusion: The BD in the great majority of infants with severe intrapartum asphyxia normalizes within 4 h of birth. The BD recovery rate of infants with adverse outcomes was similar to those with relatively good outcome. The different time patterns of asphyxial episode were not associated with differential recovery profiles.