Criteria for treatment of neonatal jaundice.

Treatment of neonatal hyperbilirubinemia is usually based on the measurements of total serum bilirubin levels. Based on empirical data, it is generally recommended to start phototherapy at lower levels in low birth weight and very low birth weight infants than in term infants, but no general agreement exists on exact limits. Treatment criteria in preterm infants do not, however, have the same empirical backing as in term infants. The very low and extremely low birth weight infants are more susceptible to bilirubin toxicity. However, bilirubin may function as an antioxidant and enzyme inducer in these infants. Several other different approaches to establish treatment criteria have also been suggested, and a summary of these are presented and discussed. With the exception of measurement of unbound bilirubin, very few of these approaches have been validated in routine clinical settings. However, unbound bilirubin is at present mainly used also as a parameter to be evaluated in relation to total bilirubin values. The present treatment criteria result in a considerable overtreatment particularly of term infants. However, with a more relaxed attitude toward neonatal hyperbilirubinemia by health care professionals, kernicterus is again reported in term infants. Because the basic mechanisms of bilirubin toxicity as well as the relative significance of the maximum serum bilirubin level compared to the duration of hyperbilirubinemia are not known, individual assessment of a newborn infant's tolerance for hyperbilirubinemia is difficult. Major changes in the empirically developed criteria for treatment of hyperbilirubinemia in the newborn are therefore not justified in the near future. For term infants, the search for validated criteria for follow-up of jaundiced infants after discharge are therefore more important than revision of existing criteria for phototherapy.