Neonatology - Neonatal Jaundice Flashcards
What is physiological jaundice?
High concentration of RBCs in foetus and neonate
These RBCs are more fragile
Foetus and neonate have less developed liver function
Foetal RBCs break down faster than normal RBCs, releasing lots of bilirubin, normally removed by placenta
This causes a rise in bilirubin 2-7 days after birth, normally resolves by day 10
What are the two categories which lead to neonatal jaundice?
Increased production of bilirubin
Decreased clearance of bilirubin
What causes an increased production of bilirubin?
- Haemolytic disease of the new-born
- ABO incompatibility
- Haemorrhage
- Intraventricular haemorrhage
- Cephalo-haematoma
- Polycythaemia
- Sepsis and DIC
- G6PD deficiency
What causes a decreased clearance of bilirubin?
- Prematurity
- Breast milk jaundice
- Neonatal cholestasis
- Extrahepatic biliary atresia
- Endocrines disoders
- Gilbert syndrome
Why is physiological jaundice worse in premature neonates?
Immature liver
Increased risk of complications e.g. kernicterus
What babies are more likely to have jaundice?
Breastfed babies
Why are breastfed babies more at risk of jaundice?
- More likely to become dehydrated if not feeding adequately
- Components of breast milk inhibit liver’s ability to process bilirubin
- Inadequate breastfeeding can slow stool passage, increasing bilirubin absorption
In breast milk jaundice should babies still be breastfed?
Yes
Benefits of breastfeeding outweigh risks of breast milk jaundice
May need extra support and advice to ensure adequate breastfeeding
What causes haemolytic disease of the new-born?
Incompatibility between Rh antigens with mother and baby
In Rh- mother, possibility of Rh+ baby, mother will then produce antibodies against Rh+ antigens and mother now sensitised
In second pregnancy, mother’s anti Rh+ antibodies can cross placenta and attack RBCs leading to haemolysis, anaemia and high bilirubin
When is jaundice prolonged in the new-born?
More than 14 days in full term babies
More than 21 days in premature babies
In prolonged jaundice what conditions are investigated for?
Biliary atresia
Hypothyroidism
G6PD deficiency
What investigations are used for neonatal jaundice?
FBC and blood film - polycythaemia or anaemia
Conjugated bilirubin - raised indicates hepatobiliary cause
Blood group testing
Direct Coombs test- for haemolysis
TFTs
Blood and urine cultures - infection or sepsis
Glucose-6-phosphate-dehydrogenase
How is jaundice managed?
Total bilirubin levels monitored and treatment threshold charts used
Phototherapy
In extremely high levels of bilirubin exchange transfusions
How does phototherapy work?
Converts unconjugated bilirubin into isomers to be excreted in the bile without needing conjugation in the liver
Eye patches used to protect eyes
Blue light best at breaking down bilirubin
Double phototherapy uses tow light-boxes
After phototherapy what should be done?
Rebound bilirubin measured
12-18 hours after
