THE ROLE OF HAEMOLYSIS IN NEONATAL HYPERBILIRUBINAEMIA AS REFLECTED IN CARBOXYHAEMOGLOBIN LEVELS

Abstract

Carboxyhemoglobin levels were measured in 250 consecutive, normal, term newborns and in a group of 75 severely jaundiced infants in an effort to assess the role of hemolysis in non-specific neonatal hyperbilirubinemia Physiologic jaundice and in severe jaundice of various etiologies. In normal newborns a significant correlation (r = 0.3293, P < 0.001) was found between 3rd-day carboxyhemoglobin and serum bilirubin levels. Significant correlations were also found between the cord and 3rd day values for carboxyhemoglobin for reticulocyte count, and for serum bilirubin. Third day Hb showed no correlation with any of the other parameters including cord Hb. Of the infants with 3rd day carboxyhemoglobin up to 0.75%, 1.7% had 3rd day serum bilirubin values above 16.0 mg/100 ml. The corresponding percentage for the infants with carboxyhemoglobin above 0.75% was 6.1%. Increased rates of hemolysis due to as yet unspecified causes play an important role in the non-specific hyperbilirubinemia of normal term newborns. As expected, high levels of carboxyhemoglobin were found in infants with severe jaundice due to Rhesus and ABO hemolytic disease and G-6-P dehydrogenase deficiency but also in jaundiced prematures and in Greek infants with severe jaundice of unknown cause.