Neonatal Phototherapy Calculator

Calculate phototherapy and exchange transfusion thresholds for neonates with precision and ease

Date and Time of Birth *

Date and Time of Measurement *

GA (Weeks)

⚖Weight (g)

Enter either GA weeks or weight — weight takes precedence

⚡Threshold Curve

🩸Measured TSB / TCB (µmol/L)

Enter a measured bilirubin to see clinical advice

Phototherapy Threshold

Calculated TSB Threshold

Enter GA or weight to generate chart

Clinical Treatment Guidelines

Evidence-based neonatal jaundice management protocols

Phototherapy

Mechanism

Unconjugated bilirubin in skin is isomerized by visible light (420–460 nm) to water-soluble “lumirubin”, which is excreted in stools and urine.

Key Points

Uses blue visible light, NOT ultraviolet
Eyes must be properly covered
Monitor temperature regularly
Continue frequent breastfeeding
Monitor with blood tests, not clinical assessment

Monitoring

TSB levels daily or more frequently if severe
Check TSB 12–24 hours after stopping
Stop when TSB >50 µmol/L below threshold

Western Cape 2006 Guidelines

Risk factors: Use one line lower for sepsis, haemolysis, acidosis, asphyxia

Monitoring intervals:

1–20 µmol/L below: repeat in 6 hours
21–50 µmol/L below: repeat in 12–24 hours
>50 µmol/L below: repeat until falling

Exchange Transfusion

Indications

High risk of bilirubin encephalopathy
TSB >85 µmol/L above threshold
Signs of bilirubin encephalopathy
Rising TSB >17 µmol/L/hr despite intensive phototherapy

Procedure

Double volume exchange (160 ml/kg over 4 hours)
Via umbilical vein or arterial catheter
Only in specialised centres

Risks

Hypothermia, hypoglycaemia
Sepsis and transfusion reactions
Incompatibility reactions

General Management

Physiological jaundice: Most infants don't require treatment

Early feeding: Reduces enterohepatic circulation

Conjugated jaundice: Treat underlying condition (surgery for biliary atresia, antibiotics for infections)

Important Clinical Notice

This calculator provides threshold values based on established guidelines. Clinical judgment should always be applied. Consider individual risk factors, and consult paediatric specialists for complex cases. Monitor phototherapy response with serial blood tests, not clinical assessment.

Professional medical calculator for neonatal phototherapy threshold determination