To Örebro University

Introduction: High levels of bilirubin in newborns can cause permanent neurodevelopmental disabilities, and it is crucial to keep the incidence low. However, the Swedish Neonatal Register revealed a high incidence of extreme neonatal hyperbilirubinemia (bilirubin ≥425 umol/L) in Region Örebro County during 2014-2019, and the reason behind this is unknown.

Aim: This study aimed to review cases of extreme neonatal hyperbilirubinemia regarding the compliance to the local guidelines, and to explore potential benefits of an alternative method considering bilirubin’s rate of rise, the ruler method.

Method: In this case series, a retrospective medical record review was performed on 63 newborns who were delivered at ≥35 gestational weeks and developed extreme hyperbilirubinemia before or during an admission to a hospital in Region Örebro County within the first 14 days of life (2014-2020).

Results: The incidence was 2.7 cases per 1000 live births during 2014-2020. Forty-three (68.3%) cases were related to failed detection/treatment initiation and 20 (31.7%) to failed treatment. Out of the newborns classified as failed detection/treatment initiation, 27 individual newborns (62.8%) could potentially have been prevented from developing extreme hyperbilirubinemia if there were no cases of non-compliance (30.2%), if a pre-discharge screening had been performed (14.0%) and if the ruler method had been applied (19/31 investigated).

Conclusion: The local guidelines used in Region Örebro County might not be sufficient in preventing the development of extreme neonatal hyperbilirubinemia. However, mandatory pre-discharge screening and a consideration of bilirubin’s current rate of rise when scheduling follow-ups could potentially lower the incidence further.