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Prediction of hyperbilirubinemia in near-term and term infants
D K Stevenson1, A A Fanaroff, M J Maisels
1Department of Pediatrics, Lucile Salter Packard Children's Hospital, Stanford, California, USA.
Insights
End-tidal carbon monoxide (ETCOc) and serum total bilirubin (STB) measurements can help predict hyperbilirubinemia in newborns. While STB is a useful predictor, combining it with ETCOc offers insights into bilirubin production and elimination, aiding in early identification of at-risk infants.
Area of Science:
- Neonatal Medicine
- Pediatric Gastroenterology
- Clinical Chemistry
Background:
- Hyperbilirubinemia is a common condition in newborns.
- Predictive markers are crucial for timely intervention.
Purpose of the Study:
- To evaluate end-tidal carbon monoxide corrected for ambient CO (ETCOc) and serum total bilirubin (STB) for predicting neonatal hyperbilirubinemia.
- To assess the combined predictive value of ETCOc and STB.
Main Methods:
- A multinational cohort study of 1370 neonates.
- Measurements of ETCOc and STB at 30 ± 6 hours of life.
- Serial STB measurements and hyperbilirubinemia defined by age-specific percentiles.
Main Results:
- 8.8% of infants developed hyperbilirubinemia.
- Mean ETCOc was higher in hyperbilirubinemic infants (1.81 ppm vs 1.45 ppm).
- ETCOc > population mean had 13.0% PPV and 95.8% NPV for hyperbilirubinemia.
Conclusions:
- STB measurement before discharge aids in predicting hyperbilirubinemia risk.
- ETCOc measurement provides insight into bilirubin metabolism but doesn't significantly improve STB's predictive ability alone.
- Combining STB and ETCOc may identify infants needing early follow-up for jaundice or related issues.
Objective:
The purpose of this study was to determine whether end-tidal carbon monoxide (CO) corrected for ambient CO (ETCOc), as a single measurement or in combination with serum total bilirubin (STB) measurements, can predict the development of hyperbilirubinemia during the first 7 days of life.
Methods:
From 9 multinational clinical sites, 1370 neonates completed this cohort study from February 20, 1998, through February 22, 1999. Measurements of both ETCOc and STB were performed at 30 +/- 6 hours of life; STB also was measured at 96 +/- 12 hours and subsequently following a flow diagram based on a table of hours of age-specific STB. An infant was defined as hyperbilirubinemic if the hours of age-specific STB was greater than or equal to the 95th percentile as defined by the table at any time during the study.
Results:
A total of 120 (8.8%) of the enrolled infants became hyperbilirubinemic. Mean STB in breastfed infants was 8.92 +/- 4.37 mg/dL at 96 hours versus 7.63 +/- 3.58 mg/dL in those fed formula only. The mean ETCOc at 30 +/- 6 hours for the total population was 1.48 +/- 0.49 ppm, whereas those of nonhyperbilirubinemic and hyperbilirubinemic infants were 1.45 +/- 0.47 ppm and 1.81 +/- 0.59 ppm, respectively. Seventy-six percent (92 of 120) of hyperbilirubinemic infants had ETCOc greater than the population mean. An ETCOc greater than the population mean at 30 +/- 6 hours yielded a 13.0% positive predictive value (PPV) and a 95.8% negative predictive value (NPV) for STB >/=95th percentile. When infants with STB >95th percentile at <36 hours of age were excluded, the STB at 30 +/- 6 hours yielded a 16.7% PPV and a 98.1% NPV for STB >75th percentile. The combination of these 2 measurements at 30 +/- 6 hours (either ETCOc more than the population mean or STB >75th percentile) had a 6.4% PPV with a 99.0% NPV. Conclusions. This prospective cohort study supports previous observations that measuring STB before discharge may provide some assistance in predicting an infant's risk for developing hyperbilirubinemia. The addition of an ETCOc measurement provides insight into the processes that contribute to the condition but does not materially improve the predictive ability of an hours of age-specific STB in this study population. The combination of STB and ETCOc as early as 30 +/- 6 hours may identify infants with increased bilirubin production (eg, hemolysis) or decreased elimination (conjugation defects) as well as infants who require early follow-up after discharge for jaundice or other clinical problems such as late anemia. Depending on the incidence of hyperbilirubinemia within an institution, the criteria for decision making should vary according to its unique population.
