Synopsis
Assess jaundice by postnatal age and gestation, identify pathological and conjugated hyperbilirubinaemia, apply the correct NICE treatment graph or table, and prevent bilirubin encephalopathy without unnecessary treatment.
- Jaundice reflects bilirubin deposition. Most newborn jaundice is unconjugated and transient, but timing, trajectory and the baby's condition determine risk.
- Never use one universal bilirubin number: plot serum bilirubin against exact age in hours on the NICE graph or table for the baby's gestational age.
- For jaundice before 24 hours, measure serum bilirubin within 2 hours and repeat every 6 hours until below the treatment threshold and stable or falling.
- At 24 hours or later, measure bilirubin within 6 hours. Visual assessment alone must not be used to estimate concentration.
- Use serum bilirubin for babies below 35 weeks and for all babies within the first 24 hours. After 24 hours at 35 weeks or more, transcutaneous measurement may screen.
- If transcutaneous bilirubin exceeds 250 micromol/L, confirm with serum. Confirm with serum whenever the value is at or above the relevant treatment threshold.
- First-line treatment above the phototherapy threshold is phototherapy with irradiance, surface area and eye protection delivered according to the device protocol.
- Intensify phototherapy when bilirubin rises faster than 8.5 micromol/L/hour, is within 50 micromol/L of the exchange threshold after 72 hours, or fails to fall within 6 hours.
- Stop phototherapy once serum bilirubin is at least 50 micromol/L below the relevant phototherapy threshold; check rebound serum bilirubin 12–18 hours later.
- Use double-volume exchange transfusion when the exchange threshold is reached or acute bilirubin encephalopathy is present, while continuing intensified phototherapy.
- In Rh or ABO haemolytic disease, consider IV immunoglobulin 500 mg/kg over 4 hours only when bilirubin continues rising faster than 8.5 micromol/L/hour despite intensified phototherapy.
- Do not stop breastfeeding routinely. Assess attachment and intake, support frequent effective feeding and add expressed milk or formula only for a defined clinical indication.
Key red flags
Visible jaundice before 24 hours requires urgent serum bilirubin measurement and medical review because haemolysis, infection and other pathology are more likely.
Lethargy, poor suck, altered tone, high-pitched cry, retrocollis, opisthotonus, apnoea or seizures raises acute bilirubin encephalopathy and possible urgent exchange transfusion.
A bilirubin at or above the gestation- and age-specific exchange threshold is an emergency even if the baby currently looks well.
Pallor, rapidly rising bilirubin, positive direct antiglobulin test, hepatosplenomegaly or family history raises haemolysis, including Rh, ABO or red-cell enzyme disease.
Dark urine that stains the nappy, pale stools, poor growth or hepatomegaly suggests conjugated jaundice and cholestasis rather than physiological unconjugated jaundice.
Prolonged jaundice beyond 14 days in a term baby or 21 days in a preterm baby needs assessment; conjugated bilirubin above 25 micromol/L requires expert advice.
Investigation priorities
Quantify jaundice and determine treatment against the correct age- and gestation-specific threshold.
Decide phototherapy, intensified phototherapy, monitoring and exchange-transfusion action.
Management branches
Visible jaundice appears in the first day.
- Measure serum bilirubin within 2 hours and arrange urgent medical review.
- Plot the value against exact age and gestation and investigate haemolysis, sepsis and other causes.
- Repeat at least every 6 hours until below threshold and stable or falling, treating according to trajectory.