Changes in total serum bilirubin during phototherapy in late preterm and term infants with non-haemolytic hyperbilirubinemia

Abstract

Background: There is no standardized method for total serum bilirubin (TSB) monitoring during phototherapy for neonatal hyperbilirubinemia and national guidelines give heterogeneous indications.

Aim: To assess the hypothesis that TSB values do not exceed exsanguino-transfusion (EXT) threshold during phototherapy and that it is possible to decrease its monitoring frequency in jaundiced infants.

Study design: We carried out a prospective observational study in which changes in TSB during phototherapy for non-haemolytic hyperbilirubinemia were recorded in a cohort of late preterm and term infants. TSB values after 6, 12, 18, and 24 h of phototherapy were compared to the EXT threshold matched to infants' gestational and postnatal age according to the specific nomogram of the Italian Society of Neonatology guidelines.

Results: We studied 105 infants who started phototherapy at a mean age of 89 ± 37 h when mean TSB was 17.1 ± 2.5 mg/dL. We found that TSB decreased during phototherapy and the difference between mean TSB and EXT threshold progressively increased during phototherapy; TSB exceeded EXT threshold in none of our patients (0%).

Conclusions: Our study demonstrates that differences between mean TSB and EXT threshold increased during phototherapy in late preterm and term infants with non-haemolytic hyperbilirubinemia; in none of our patients TSB exceeded EXT threshold. Our findings support the possibility of safely decreasing TSB monitoring during phototherapy, thus limiting noxious painful stimuli in neonates.

Keywords: Hyperbilirubinemia; Infant; Monitoring; Phototherapy; Total serum bilirubin.