Accuracy of Transcutaneous Bilirubinometer in Predicting Serum Bilirubin in Newborn

Abstract

Accuracy of Transcutaneous Bilirubinometer in Predicting Serum Bilirubin in Newborn

Amornrat Tritiprat MD*

Tanattha Kittisopee PhD**

* Department of Pediatrics, Taksin Hospital, Bangkok Metropotitan Administration (BMA)

** Department of Social and Administrative Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University

Objectives: To study the correlation between transcutaneous bilirubin (TcB) and serum bilirubin (TsB), and find a cut off level of TcB as a criterion for deciding whether TsB should be done.

Methods: This study was a diagnostic test study design, which studied in healthy jaundiced term newborns, aged ฃ 7 days who underwent test for TsB from January to March 2010 at postpartum ward, Taksin hospital, BMA. TcB was measured by directly applying the device on the forehead of the subjects using a bilirubinometer, Bilicheckฎ. Then it was compared to TsB which was determined by the calorimetric method.

Results: One hundred and sixty two newborns were enrolled in this study. The means and standard deviations of TsB and TcB were 12.6 ฑ 2.6 mg/dl and 12.5 ฑ 2.6 mg/dl, respectively. The correlation coefficient between TsB and TcB was significant with the r of 0.69 (p-value < 0.001). The optimal cut off levels of TcB as a criterion for deciding whether TsB should be done were 9, 11 and 11 mg/dl for newborns aged 25-48, 49-72 and > 72 hours, respectively with the sensitivity of 100%, 95.2%, 100% and the specificity of 42.9%, 40.5%, 32.6% respectively.

Conclusion: Transcutaneous bilirubin had fair correlation with serum bilirubin with statistically significant and may be used to screen whether serum bilirubin should be done in each age group of healthy term newborns.

Keywords: transcutaneous bilirubin (TcB), serum bilirubin (TsB), neonates