6615 Comparing TCB, gas bilirubin and Laboratory bilirubin levels with the severity of jaundice and the decision to start treatment

Objectives This study was initiated due to a rise in infants requiring jaundice screening at our paediatric ambulatory unit, often referred by community midwives. Our main goal was to compare Transcutaneous Bilirubin(TCB), gas bilirubin, and laboratory bilirubin levels to streamline the diagnostic process, reduce waiting time for results, and make quicker decisions about admission or treatment. Aim To enhance clinical decision-making for neonatal jaundice by providing insights into the relationships between TCB, gas and laboratory bilirubin levels. Methods This retrospective study, conducted collaboratively with a senior nurse and a paediatric consultant, followed established clinical guidelines and protocols for data collection. Data collected on infants referred for jaundice screening from August 2020 to June 2023, recording TCB measurements, gas bilirubin levels, and laboratory bilirubin results for comparison. Results A total of data on 105 full-term infants (≥37 weeks' gestation) was retained for analysis. For TCB, the sample of 93 had a mean of 263.76 micromol/l and a standard deviation of 38.45 micromol/l. Gas bilirubin, with a sample of 89, had a mean of 236.83 micromol/l and a standard deviation of 58.91 micromol/l. In the case of laboratory bilirubin, derived from a sample of 93, the mean was 236.09 micromol/l, and the standard deviation was 50.28 micromol/l. When TCB was under 250 micromol/l, gas bilirubin was also under 250 micromol/l in 88.8%, blood bilirubin was in agreement in 94%. Conversely, TCB values equal or above 250 micromol/l had only a 44% chance of gas bilirubin and a 48% chance of laboratory bilirubin being in agreement. However, while comparing gas bilirubin and laboratory bilirubin, gas bilirubin below 250 micromol/l had a 90.0% probability of laboratory bilirubin being below 250 micromol/l. For gas bilirubin equal or above 250 micromol/l, there was an 83.3% likelihood of laboratory bilirubin reaching or exceeding 250 micromol/l. Notably, gas bilirubin at or above 300 micromol/l had 100% chances for laboratory bilirubin being 300 micromol/l or higher. Conclusion Babies with TCB levels less than 250 micromol/l consistently exhibited similar levels in both gas and laboratory blood tests. Infants with TCB levels above 250 micromol/l should be referred to the hospital for a blood bilirubin assessment as bloods bilirubin levels might be below or higher Results show that clinicians should be confident in the linear relationship between blood gas bilirubin and laboratory bilirubin levels, whether their levels are above or below 250 micromol/l. Therefore, if gas bilirubin exceeds 250 micromol/l and is above phototherapy line, initiating treatment without waiting for the laboratory results may save valuable time and reduce risks associated with waiting without treatment. Reference https://www.nice.org.uk/guidance/cg98/evidence/full-guideline-245411821.