Why neonatal jaundice demands systematic assessment
Jaundice affects up to 60% of term newborns in the first week of life. Most cases are benign physiological jaundice — but a small subset will progress to severe hyperbilirubinaemia and, without intervention, bilirubin-induced neurological dysfunction (BIND) or kernicterus. The Bhutani nomogram gives you an objective, hour-specific risk classification that removes the guesswork from discharge decisions and phototherapy thresholds.
The nomogram explained
Developed by Vinod Bhutani and colleagues and published in Pediatrics in 1999, the nomogram plots total serum bilirubin (TSB) or transcutaneous bilirubin (TcB) against postnatal age in hours. It defines four risk zones:
- High risk zone (above the 95th percentile): Immediate action required
- High-intermediate zone (75th–95th percentile): Close follow-up within 24 hours
- Low-intermediate zone (40th–75th percentile): Follow-up within 48 hours
- Low risk zone (below the 40th percentile): Routine follow-up
How to plot correctly
Step 1 — Establish postnatal age precisely. Bilirubin values must be plotted against age in hours, not days. A value of 200 µmol/L at 24 hours is high-risk; the same value at 96 hours is low-risk. Use the exact date and time of birth. Step 2 — Use the correct units. The original nomogram uses mg/dL. To convert µmol/L to mg/dL, divide by 17.1. Clinit's bilirubin tool accepts both units and converts automatically. Step 3 — Record measurement type. Transcutaneous bilirubin (TcB) is a useful screening tool but consistently reads 0–3 mg/dL lower than TSB. If TcB plots near or above the 75th percentile, obtain a confirmatory TSB before making treatment decisions. Step 4 — Apply risk factors. The phototherapy threshold is lower for infants with any of the following:- Isoimmune haemolytic disease (ABO or Rh incompatibility)
- G6PD deficiency
- Asphyxia, lethargy, or temperature instability
- Sepsis
- Acidosis
- Albumin < 3 g/dL
- Gestational age < 38 weeks
Phototherapy thresholds by gestational age
The American Academy of Pediatrics (AAP) 2022 updated guidelines use gestational age and neurotoxicity risk factors to set individualised thresholds. The Clinit pediatrics module uses these thresholds:
| Gestational age |
| Lower risk threshold |
| --- |
| --- |
| ≥ 38 weeks, no risk factors |
| 18 |
| 35–37 weeks |
| 15 |
| < 35 weeks |
| — |
Safe discharge criteria
Before discharging a jaundiced newborn:
- TSB or TcB is below the phototherapy threshold on the nomogram for the infant's hour-specific age
- TSB is falling or stable on two consecutive measurements
- Infant is feeding well (≥ 6–8 feeds per 24 hours) and passing stool
- Parents have received written instructions on jaundice warning signs
- Follow-up is arranged within 24–48 hours if the infant was in the intermediate zone at discharge
Causes of pathological jaundice to exclude
Any bilirubin in the high-risk zone, any jaundice appearing in the first 24 hours, or any conjugated bilirubin > 1 mg/dL warrants investigation for:
- ABO or Rh incompatibility (direct Coombs test)
- G6PD deficiency
- Spherocytosis
- Biliary atresia (conjugated hyperbilirubinaemia)
- Neonatal hepatitis
- Sepsis
How Clinit manages neonatal jaundice
The Clinit pediatrics module includes a dedicated bilirubin tracker linked to the patient's birth record. You enter the bilirubin value, measurement method (TcB or TSB), and the system calculates exact postnatal age in hours automatically. The value is plotted on the Bhutani nomogram in real time, with the risk zone highlighted. The phototherapy threshold is calculated based on gestational age and the risk factors you select from a checklist. Re-check reminders are set from the same screen — no separate calendar entry needed.
Key takeaways
The Bhutani nomogram is not just a research tool — it is a practical clinical decision aid that should be used for every jaundiced newborn at every bilirubin measurement. Plot early, plot accurately, and factor in gestational age and haemolytic risk. The difference between routine monitoring and urgent phototherapy is often a single hour-specific data point plotted correctly.