[Assessment of bilirubin to albumin ratio as a criterion for exchange transfusion in severe neonatal hyperbilirubinemia]

ABSTRACT

Total Serum Bilirubin level [TSB] has been the gold standard indicator for exchange transfusion [ET] in the neonates for many years. This study was designed to assess the bilirubin/albumin [B/A] ratio as an indicator for ET in comparison with TSB. In the NICU and newborn services at Amirkola Children's Hospital [ACH] in the north of Iran, 90 neonates in 3 groups were selected. The first group was 30 neonates who required exchange transfusion [ET], because of severe hyperbilirubinemia [HB] based on the TSB according to the ACH protocol .The second group was 30 neonates, treated with phototherapy due to pathologic HB and the Other 30 neonates had only physiologic neonatal jaundice. Blood samples were checked for serum bilirubin, albumin and B/A ratio in addition to the routine lab tests for HB. Sensitivity, specificity, negative predictive value, positive predictive value, and relative risk were assessed for B/A ratio as a determinant to do ET. The mean +/- SD of B/A ratio was 6.0847 +/- 0.9870 in blood exchange group, 4.1680 +/- 0.5480 in phototherapy group and 1.7677 +/- 0.5061 in healthy neonate group. "Cut off level" of B/A ratio calculated to do ET was 4.50.The B/A ratio of 4.5 has a "positive predictive value" of 75% and a "negative predictive value" of 100%. A B/A ratio equal to 4.5 among newborns Who required exchange transfusion has a high value as a criterion to do ET, although further study is required to recommend it alone in clinical practice. So we recommend doing B/A ratio in accompaniment with TSB as an adjunctive test