Neonatal Hyperbilirubinemia in the Low-Intermediate–Risk Category on the Bilirubin Nomogram

Abstract

Predischarge bilirubin screening predicts neonatal hyperbilirubinemia. We evaluated the incidence of false-negative bilirubin screening among readmissions for hyperbilirubinemia. In healthy term and late preterm, predominantly breastfeeding newborns, predischarge transcutaneous bilirubin values were plotted on the hour of life-specific bilirubin nomogram and confirmed with plasma total bilirubin in those with a transcutaneous reading ≥ 75th percentile, or between the 41st and 75th percentiles in the presence of predictive icterogenic risk factors. False-negative bilirubin screen was defined as a predischarge bilirubin value ≤ 75th percentile in a newborn who was subsequently readmitted for phototherapy. Of a total of 25439 neonates born between 2008 and 2009, 143 (0.56%) were readmitted with a mean plasma total bilirubin of 18.7 ± 1.7 mg/dL at 125 ± 54 hours. False-negative predischarge bilirubin screen was identified in 46 (32.2%). Of these, 6 (4.2%) were in the low-risk zone (≤ 40th percentile, relative risk [RR] = 1) and 40 (28%) in the intermediate-low-risk zone (41st-75th percentile, RR 7.62 [95% confidence interval 3.23-17.96]). Of those in the high-risk zones, 76 (53.1%) were in the intermediate-high-risk zone (76th-95th percentile, RR 25.32 [11.03-58.10]) and 21 (14.7%) in the high-risk zone (>95th percentile, RR 27.78 [11.23-68.70]). Predischarge bilirubin levels in newborns classified as low risk did not eliminate the risk of readmission for hyperbilirubinemia. All newborns including those at low risk must be vigilantly observed for subsequent hyperbilirubinemia.