STUDIES OF NON-HEMOLYTIC HYPERBILIRUBINEMIA IN PREMATURE INFANTS

1. A prospective clinical study of nonhemolytic hyperbilirubinemia in premature infants included 187 infants, of whom 100 had hyperbilirubinemia above 18 mg/100 ml and 87 had bilirubin levels never in excess of 15 mg/100 ml. In a random fashion, the infants with hyperbilirubinemia were divided evenly and either received replacement transfusions or did not. 2. Of the 50 infants in the exchange transfusion group, bilirubin levels were adequately controlled in 48 infants. There was no mortality associated with the exchange transfusion procedure. After 1 year, there does not appear to be any definite evidence of kernicterus in this group. 3. In the no-exchange group, 10 of the 50 infants had levels of bilirubin over 24 mg/ 100 ml for more than 48 hours. Of these, 1 developed fatal kernicterus. Eight of the other 9 infants, whose bilirubin values exceeded 24 mg/100 ml, and 32 of the original 40, whose bilirubin levels were over 18 but below 24 mg/100 ml, were examined neurologically after 1 year. No evidence of kernicterus was found. 4. Seventy-five of the 87 control infants were also examined neurologically after 1 year and none had evidence of kernicterus. 5. The evidence to date suggests that exchange transfusions in the management of non-hemolytic hyperbilirubinemia of the premature not associated with clinical factors which may enhance the development of kernicterus such as asphyxia, hypoproteinemia, sepsis, etc., need not be performed for unconjugated bilirubin values under 24 mg/100 ml. We believe that infants who will develop bilirubin levels in excess of 24 mg/100 ml may be anticipated if their plasma values exceed 20 mg/100 ml between 73 to 96 hours of age or 22 mg/100 ml between 96 and 120 hours. 6. The validity of these conclusions is dependent upon the long-term follow-up of these infants.