Simultaneous measurement of total transcutaneous bilirubin on forehead and chest as a predictive model for total serum bilirubin in premature and term newborns

Abstract

Background: detection of hyperbilirubinemia in neonates has become a challenge for healthcare systems. The objective of this study was to determine the usefulness of simultaneous measurements of total transcutaneous bilirubin on forehead (TTBf) and total transcutaneous bilirubin on chest (TTBs) as a predictive model for total serum bilirubin (TSB) in premature and term neonates. Material and methods: a transverse and analytical study in neonates with gestational age between 30 and 42 weeks, from January 21 through April 30, 2013, at a public gynecology, obstetrics, and neonatology hospital. Pearson correlation was determined between TSB/TTBf and TSB/TTBs. Linear regression analyses were conducted for one and for several independent variables. Results: for 89 simultaneous determinations the correlation between TSB/TTBf was 0.8411 and for TSB/TTBs 0.7942 (p < 2.2 E-16 for both cases). With the simple regression analysis between TSB and TTBf the equation was: TSB = 2.1187 + 0.7035 × TTBf (p < 2.2 E-16, R2 = 70.75%, R2 adjusted = 70.41%); for TSB and TTBs the equation was: TSB = 2.0405 + 0.6349 × TTBs (p < 2.2 E-16, R2 = 63.07%, R2 adjusted = 62.65%). With multiple regression analysis for TSB vs. TTBf, TTBs the equation was: TSB = 1.620 + 0.503 × TTBf + 0.224 × TTBs (p < 2.2 E-16, R2 = 72.87%, R2 adjusted = 72.24%). Conclusions: it was proven that the model that included TTBf and TTBs allowed us to obtain a better prediction of TSB than models with a single measurement of TTB in hospitalized premature and term neonates.

Keywords

• transcutaneous bilirubin, bilirubinometer, neonatal hyperbilirubinemia, kernicterus.