A Comparison of Significant Bilirubin Rebound after Discontinuation of Phototherapy in Two Groups of Neonates in Valiasr Hospital: A Randomized Clinical Trial

The aim of this study is to compare significant post-phototherapy bilirubin rebound in two groups of neonates, with two levels of bilirubin, at discontinuation of phototherapy. One hundred and fifteen neonates ≥35 weeks of gestationl age (GA), admitted due to hyperbilirubinemia in the Neonatal Ward of Valiasr Hospital, were randomly divided into two groups: group A and group B. In group A, phototherapy was discontinued when bilirubin level reached 11 mg/dl, or the 40th percentile of the Bhutani nomogram, while in group B, it took place at bilirubin level of 13 mg/dl or the 75th percentile. After 24 hr, total serum bilirubin was measured. Significant post-phototherapy rebound was defined as bilirubin increase of more than 2 mg/dl or the 95th percentile. A total of 13 (11.3%) neonates out of 115 participants developed significant rebound, 9 of which (69%) were in group A, and the rest (21%) were in group B, which was not considered a significant difference (p=0.13). Comparison of the two groups showed no significant difference concerning the correlation between rebound and the infant’s age, in hr of starting phototherapy. However, the number of neonates in group B, who received phototherapy before 48 hr of age, was too small to draw reliable conclusions. Logistic regression analysis showed that intravenous serum therapy was the only risk factor significantly associated with rebound (p=0.005). According to this study, it is shown that discontinuation of phototherapy in hyperbilirubinemia, at lower bilirubin levels, would not prevent rebound. Moreover, no association was found between the known risk factors and rebound.