Objective: Our aim was to validate a strategy for assessing the risk of significant hyperbilirubinemia in newborns with gestational ages of ≥35 weeks by combining predischarge bilirubin percentile data with gestational age data, for a European, predominantly white population.
Methods: We conducted a prospective cohort study with 463 newborns with gestational ages of ≥35 weeks who were admitted to the well-infant nursery. Total bilirubin levels were measured daily until discharge and once after discharge, between the third and eighth days of life, by using a Bilicheck device (Respironics, Murrysville, PA). The values obtained (<52 hours) were plotted on an hour-specific bilirubin nomogram to determine the infant's bilirubin percentile, expressed as a risk zone. Patients were assigned to 1 of 3 risk groups (very low, low, or high) on the basis of a combination of risk zone and gestational age data and were monitored prospectively for the development of significant hyperbilirubinemia. The 95% confidence interval (CI) for the prevalence of significant hyperbilirubinemia was estimated with the binomial distribution method.
Results: Forty-four infants (11%) developed significant neonatal hyperbilirubinemia. The risks of developing significant hyperbilirubinemia were 1.3% (95% CI: 0.2%-3.7%) for the very low risk group (n = 230 [58.1%]), 3.4% (95% CI: 0.7%-9.8%) for the low risk group (n = 86 [21.7%]), and 47.50% (95% CI: 36.2%-59.0%) for the high risk group (n = 80 [20.20%]).
Conclusions: The proposed strategy, based on predischarge bilirubin level and gestational age data, was a valid method for significant hyperbilirubinemia risk assessment in our population.