Pharmacokinetics-Based Optimization of Phototherapy in Neonates Undergoing Treatment for Hyperbilirubinemia

Introduction: Neonatal jaundice results from combined effects of both increased production of bilirubin and decreased hepatic excretory capacity in neonates. Since its discovery, phototherapy is the most widespread treatment used in neonatal jaundice. In this work, we try to search for a relationship between exposure to phototherapy and decrease in serum bilirubin (linearity vs proportionality). Methods:The present research was non-randomized prospective study conducted in the Neonatal Intensive Care Unit (NICU), Department of Paediatrics, AIIMS, New Delhi, and the Department of Pharmacology, AIIMS, New Delhi, India. Subjects were recruited from neonates admitted in NICU AIIMS, which meets our selection criteria. Infants were given a low dose of either phototherapy continuously or phototherapy for the first six hours and a double dose of phototherapy for the next six hours. Samples were collected before the beginning of the study (0 hours) and then at six and 12 hours. Bilirubin concentration was measured using HPLC and (LC-MS/MS). Results and conclusion:The percentage of reduction during the 6-12-hour interval was compared with that during the 0-6-hour interval if all experimental conditions were kept unchanged. A relationship curve between percentage of reduction and irradiance was created based on the percentage of reduction in serum bilirubin during the 0-6-hour and 0-12-hour intervals. The present study suggests that the relationship between efficacy, as measured by percentage of reduction in serum bilirubin, and irradiance is unlikely to be linear. Collected data are insufficient to clearly distinguish between proportionality and saturation point, considering that the results may be possible with both of these hypotheses.