Transcutaneous bilirubinometry is not influenced by term or skin color in neonates

Abstract

Background: The utility of transcutaneous bilirubin measurements (TcB) in screening for hyperbilirubinemia in preterm infants (<34 weeks) and in non-white infants remains a matter of debate.

Aim: To evaluate accuracy of TcB in preterm and term infants of different ethnic backgrounds, using a second generation bilirubinometer.

Study design: The Draeger JM-103® device was used to measure TcB. Eighty five measurements of TcB and total serum bilirubin (TSB) were retrospectively compared. Neonates were stratified into groups according to gestational age: <34 weeks (group 1, n=44) and >34 weeks (group 2, n=41), and according to ethnic origin: Caucasians (group A, n=49) and non-Caucasians (group B, n=36). Statistical analysis, using Pearson's correlation coefficient (r) and Bland-Altman analysis were performed to evaluate correlation and agreement between TSB and TcB values. Multiple linear regression was used to control for confounders for TSB values.

Results: Correlation between TSB and TcB was high. Pearson's correlation coefficients were over 0.9 in all groups (0.910, 0.908, 0.916 and 0.934, p<0.0001 in groups 1, 2, A, and B respectively). Bland-Altman plots showed acceptable and close limits of agreements (56.8/-57.7, 54.2/-67.2, 57.7/-55.8, and 51.3/-69.9μmol/L in groups 1, 2, A and B respectively) with a trend for TcB to overestimate TSB in groups 2 and B. Birth term and skin color were not identified as confounding factors for predicting TSB in multiple linear regression.

Conclusions: TcB measurements using the Draeger JM-103® device correlate significantly with TSB, regardless of term and skin color. Transcutaneous bilirubinometry seems to be a safe and cost-effective screening method for severe hyperbilirubinemia in newborns of different terms and ethnic origins.

Keywords: Bland–Altman difference plots; Correlation coefficient; Jaundice; Preterm and term infants; Skin color; Transcutaneous bilirubin evaluation.