Rapid fluorometric assay of bilirubin binding parameters in newborn infants.

Using a self-calibrating, digital hematofluorometer, bilirubin binding parameters were determined for whole blood specimens from 20 premature infants from day one to day six of life. The mean gestational age of the infants was 31.0 +/- 2.7 weeks and the birth weight was 1419 +/- 713.2 grams. There was a high correlation between the total blood bilirubin as determined by the hematofluorometer and total serum bilirubin as measured by a modified Jendrassik Grof method. An agreement between the hematofluorometer and coulter counter hemoglobin values was noted. There was a high correlation between the reserve bilirubin binding capacity as determined by the hematofluorometer and modified sephadex gel adsorption. No difference in the bilirubin binding parameter values was noted among infants treated and non-treated with phototherapy. Bilirubin binding parameters could be performed on the portion of heparinized specimen collected for blood gas measurement in infants with respiratory distress. The adaptability and 24 hour utility of the hematofluorometer within the neonatal intensive care area provides a convenient, practical and objective approach in the management of neonatal hyperbilirubinemia.