Neonatal Jaundice & Phototherapy Estimator

Hour-specific total serum bilirubin risk assessment, phototherapy cutoffs, and exchange transfusion thresholds aligned with CPS 2025 guidelines.

Infant Timeline & Maturity

Hours 12 to 168

Infant Age in Hours: 48 hours(~Day 3 of life)

12h24h (D1)48h (D2)72h (D3)96h (D4)120h+ (D5+)

Gestational Age

Enter Measured Bilirubin Value (µmol/L)

µmol/L

Equivalent: 12.3 mg/dL

The presence of any of the following lowers the treatment threshold curve per CPS 2025 guidelines:

Isoimmune Hemolytic Disease / Positive DATRh disease, ABO incompatibility with positive direct antiglobulin test

G6PD Deficiency or Other Hemolytic AnemiasRapid uncoupling of bilirubin binding and elevated hemolysis risk

Asphyxia, Acidosis, or 5-min APGAR < 7Cord or arterial blood gas pH < 7.15, therapeutic hypothermia

Suspected Sepsis, Hypothermia, or LethargyBlood cultures drawn, temperature instability, clinical weakness

Serum Albumin < 30 g/L (< 3.0 g/dL)Reduced binding capacity increasing free unconjugated neurotoxic bilirubin

Assessment at 48h of LifePhysiological Range (Below Treatment Threshold)

210µmol/L(12.3 mg/dL)

Risk Curve: Lower Risk (≥38 weeks, clinically well, no neurotoxicity risk factors)

Phototherapy Cutoff300 µmol/L(17.5 mg/dL)

Exchange Transfusion385 µmol/L(22.5 mg/dL)

✓ Bilirubin is 90 µmol/L BELOW phototherapy threshold.

CPS 2025 Clinical Directive

•TSB (210 µmol/L) is comfortably below treatment threshold (300 µmol/L).
•Routine newborn nursery follow-up; ensure lactation latch support and count wet/soiled diapers.
•Repeat clinical visual inspection in 24 hours or before discharge.
•Advise outpatient pediatric/primary care visit within 24–48 hours of hospital discharge.

Next recommended serum evaluation in: 24 hours

Jaundice travels head-to-toe as bilirubin levels climb. Visual blanching in natural sunlight:

Zone 1: Face & Eyes~70–100 µmol/L (4–6 mg/dL)

Zone 2: Upper Chest~100–150 µmol/L (6–9 mg/dL)

Zone 3: Abdomen & Thighs~150–200 µmol/L (9–12 mg/dL)

Zone 4: Lower Legs & Arms~200–250 µmol/L (12–15 mg/dL)

Zone 5: Palms & Soles of Feet> 250 µmol/L (> 15 mg/dL) ⚠️

Note: Visual inspection alone can underestimate severity in darker skin tones; always confirm with transcutaneous (TcB) or serum (TSB) measurement.