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Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Pre-phototherapy total serum bilirubin levels in extremely preterm infants
Thivia Jegathesan1,2, Joel G Ray1,3,4, Charles Donald George Keown-Stoneman5,6
1Institute of Medical Sciences, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
Insights
Extremely preterm infants often need phototherapy for hyperbilirubinemia. This study found significant differences between statistically derived total serum bilirubin (TSB) levels and current consensus-based thresholds for initiating treatment in these vulnerable newborns.
Area of Science:
- Neonatalogy
- Pediatrics
- Perinatal Medicine
Background:
- Extremely preterm infants are susceptible to hyperbilirubinemia and its complications.
- Current phototherapy guidelines for these infants are based on consensus (CB) rather than empirical data.
Purpose of the Study:
- To statistically derive pre-phototherapy total serum bilirubin (TSB) levels in extremely preterm infants.
- To compare these derived levels with existing CB thresholds.
Main Methods:
- A multi-site retrospective cohort study involving 642 infants born between 24 and 28 weeks' gestation.
- Generation of pre-phototherapy TSB percentile levels at 24 hours of age.
- Comparison of generated percentiles with published CB thresholds.
Main Results:
- Significant differences were observed between derived TSB percentiles and CB thresholds across gestational age groups.
- For infants born at 24-25 weeks, the 95th percentile TSB was 35.3 µmol/L higher than the CB threshold.
- For infants born at 26-27 weeks, the 95th percentile TSB was 43.3 µmol/L higher than the CB threshold.
Conclusions:
- Statistically derived pre-phototherapy TSB levels offer a clearer understanding of TSB patterns in extremely preterm infants.
- Current CB thresholds may not accurately reflect TSB levels in this population, with some infants receiving phototherapy below established limits.
Background:
Extremely preterm infants are prone to hyperbilirubinemia and its sequelae. Currently recommended thresholds for initiating phototherapy in these newborns are consensus-based (CB).
Methods:
A multi-site retrospective cohort study of 642 infants born at 240/7 to 286/7 weeks' gestation, between January 2013 and June 2017, was conducted at three NICUs in Canada. Pre-phototherapy TSB percentile levels at 24 h of age were generated and contrasted with published CB thresholds.
Results:
Among infants born 240/7 to 256/7 weeks' gestation, the differences between our TSB percentiles vs. the CB threshold of 85.0 µmol/L were 10.0 µmol/L (95% CI, 6.0-16.0) at the 75th percentile and 35.3 µmol/L (95% CI, 26.1-42.8) at the 95th percentile. Respectively, among infants born at 260/7 to 276/7 weeks, differences were 19.4 µmol/L (95% CI, 16.8-23.4) and 43.3 µmol/L (95% CI, 34.7-46.9). Born at 280/7 to 286/7 weeks' gestation, differences between our 75th and 95th TSB percentiles and the CB threshold of 103 µmol/L were 6.9 µmol/L (95% CI, 3.2-12.0) and 36.0 µmol/L (95% CI, 31.0-44.3), respectively.
Conclusions:
We provide statistically derived pre-phototherapy TSB levels that may clarify patterns of pre-phototherapy TSB levels in extremely preterm infants.
Impact:
We present statistically derived pre-phototherapy total serum bilirubin levels in a cohort of extremely preterm infants. Most of these preterm infants received phototherapy-some at below currently published thresholds. There are notable differences between our statistically derived pre-phototherapy TSB levels and currently published lower limit TSB thresholds for phototherapy. Our study results assist in the understanding of pre-phototherapy TSB levels in extremely preterm infants.
