From the Guidelines
Bilirubin checks in the ER should be guided by the total serum bilirubin (TSB) level, which is the definitive diagnostic test to guide all interventions, especially in newborns with jaundice. When evaluating newborns with jaundice in the ER, it is essential to measure TSB if the transcutaneous bilirubin (TcB) reading is within 3.0 mg/dL of the phototherapy treatment threshold, if the TcB exceeds the phototherapy treatment threshold, or if the TcB is ≥15 mg/dL, as recommended by the 2024 Pediatrics study 1. The rate of rise of bilirubin levels can also be used to identify possible hemolysis, with a rapid rate of rise (≥0.3 mg/dL per hour in the first 24 hours or ≥0.2 mg/dL per hour thereafter) being suggestive of ongoing hemolysis.
In the ER setting, bilirubin testing is crucial to assess the risk of kernicterus in newborns, with treatment thresholds varying by age and risk factors, such as gestational age, neurotoxicity risk factors, and age of the infant in hours, as outlined in the 2024 Pediatrics study 1. The decision to discontinue phototherapy should be individualized, considering the TSB level at which phototherapy was initiated, the cause of the hyperbilirubinemia, the difference between the TSB level and the phototherapy threshold, and the risk of rebound hyperbilirubinemia. Key considerations for bilirubin checks in the ER include:
- Measuring TSB to guide interventions
- Using TcB readings to determine the need for TSB measurement
- Evaluating the underlying cause of hyperbilirubinemia
- Considering the risk of kernicterus in newborns
- Individualizing the decision to discontinue phototherapy based on TSB levels and other factors.
Bilirubin elevation should prompt additional liver function tests, including ALT, AST, alkaline phosphatase, and GGT, to provide a more complete picture of liver function, as these tests can help distinguish between different causes of hyperbilirubinemia, such as hepatitis, gallstones, hemolysis, or Gilbert's syndrome. The test requires a simple blood draw, and results are typically available within hours, making it a practical diagnostic tool in the emergency setting when liver or biliary disease is suspected.
From the Research
Bilirubin Checks in the ER
- Bilirubin checks are crucial in evaluating patients with jaundice, as an elevated level of bilirubin almost always indicates the presence of an underlying disease state 2.
- In adults, the evaluation of jaundice starts with a careful history and physical examination, followed by directed imaging of the biliary tree and liver 2.
- In newborns, neonatal jaundice due to hyperbilirubinemia is common, and most cases are benign, but it is essential to evaluate all newborns for risk factors for bilirubin-related neurotoxicity 3.
- The American Academy of Pediatrics recommends universal neonatal hyperbilirubinemia screening in newborns 35 weeks' gestational age or greater, and phototherapy should be used only for newborns who exceed thresholds recommended by the current AAP hour-specific phototherapy nomograms 3.
Importance of Bilirubin Checks
- Bilirubin checks can help identify underlying conditions such as hemolytic diseases, liver disease, or biliary tract disease 4, 5.
- In newborns, early detection of hyperbilirubinemia through bilirubin screening and prompt treatment can prevent severe complications such as kernicterus 3, 6.
- In adults, a comprehensive medical history, review of systems, and physical examination, along with laboratory evaluation and imaging, can help differentiate potential causes of jaundice and guide management 5.
Guidelines and Recommendations
- The National Institute for Health and Care Excellence guideline recommends measuring the bilirubin level within 6 hours in all babies who are visibly jaundiced 4.
- The American Academy of Pediatrics guidelines emphasize higher thresholds for intervention, stratified by gestational age and risk factors, for newborns with hyperbilirubinemia 3, 6.
- The evaluation of jaundice in adults should include a comprehensive medical history, review of systems, and physical examination, along with laboratory evaluation and imaging 5.