Ms. D.E. Vader-van Imhoff: The management of hyperbilirubinemia in preterm infants

PhD ceremony: Ms. D.E. Vader-van Imhoff, 16.15 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: The management of hyperbilirubinemia in preterm infants

Promotor(s): prof. A.F. Bos

Faculty: Medical Sciences

This thesis presents a variety of studies aiming to improve the management of hyperbilirubinemia in preterm infants of less than 35 weeks of gestational age. An excess amount of unconjugated bilirubin in the blood results in yellow discoloration of the skin, which can be observed in neonatal hyperbilirubinemia. Hyperbilirubinemia is very common in preterm infants and is potentially neurotoxic. Preterm infants are more prone to bilirubin neurotoxicity than their term counterparts. Treatment consists of phototherapy or a blood exchange transfusion and is based on the total serum bilirubin (TSB) concentration.

A large variation in TSB thresholds existed in the neonatal intensive care units due to lack of evidence based thresholds. Therefore we developed novel, consensus-based TSB treatment thresholds for hyperbilirubinemia in preterm infants. To further standardize the care of hyperbilirubinemia, we made recommendations on the effective use of phototherapy and we introduced a tailor made quality assessment scheme for neonatal bilirubin and albumin laboratory measurements. We also analyzed the relation of transcutaneous bilirubin (TcB) and TSB measurements during phototherapy and found that TcB levels measured on the covered hipbone can be used in preterm infants receiving phototherapy and can theoretically reduce the number of blood samples to determine the TSB concentration. Furthermore, we investigated whether the neurodevelopmental outcome of preterm infants improved when the Bilirubin/Albumin ratio was used in the management of hyperbilirubinemia next to the TSB concentration, and found no such differences.