Accuracy of Transcutaneous Bilirubin Measurement from Unexposed Skin with a New Generation Device in Neonates Receiving Phototherapy

Aim: Transcutaneous bilirubin (TCB) measurement methods cause false results during and after phototherapy (PT), so bilirubin levels are followed by total serum bilirubin (TSB) measurement, which causes taking blood samples and increases the risk of infection. We compared the TCB measurements made with Bilicare (TM) and TSB measurements by preventing PT exposure of a part of the skin in newborns receiving PT and evaluating the reliability of the measurements made with Bilicare (TM) after PT. Methods: This study was conducted between 01 February-30 June 2020 as a single-center cross-sectional study. The study included newborns aged 35 weeks and up who were admitted to a neonatal intensive care unit for PT. TSB measurements were reviewed by the hospital automation system. Bilicare (TM) bilirubin meter was used for TCB measurements. Simultaneous TSB and TCB measurements were made before PT. The skin area to be measured was covered with a radio-opaque patch. After PT, simultaneous TSB, exposed skin area TCB, and patched skin area TCB were measured. Simultaneous TSB and TCB measurements were repeated 24 h after the end of PT. The relationship between these data was evaluated statistically. Results: This study was conducted with 171 late preterm and term newborns with a gestational age of >= 35 weeks. 79 (46.1%) were female and 92 (53.9%) were male newborns. The mean gestational age was 38.3 +/- 1.15 weeks. When maternal and newborn blood groups were evaluated, 107 (62.5%) had no blood incompatibility, 53 (30.9%) had ABO incompatibility incompatibility, 9 (5.2%) had Rh incompatibility, 1 (0.6%) had subgroup incompatibility, and 1 (0.6%) had ABO incompatibility and Rh incompatibility. The correlation coefficient (r) of TSB and TCB measurements made before PT was 0.97 and a strong correlation was found. A correlation coefficient (r) of 0.98 and a strong correlation between closed skin area TCB measurement and TSB measurement immediately after PT were detected. The correlation coefficient (r) was 0.96 and a strong correlation was found between the TCB and TSB measurements performed 24 h after the PT was terminated. Conclusion: This study shows that TCB measurements made from unexposed areas can be safely measured in patients with PT.