Neonatal Jaundice

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Neonatal Health
Assoc Prof Zsuzsoka Kecskes
Dept of Neonatology
The Canberra Hospital
Topics covered
• Jaundice
• Hips
• Cardiac/Oxygen Saturation Monitoring
Neonatal jaundice
What is jaundice?
What is jaundice?
• Jaundice is bilirubin that is deposited in the skin
and mucous membranes. It is the end product
of haem breakdown.
• Lysis of red blood cells releases haem from
haemoglobin, haem is then converted to
bilirubin and excreted.
Bilirubin metabolism
Uridine diphosphate glucuronyl
transferase (UDPGT)
Prevalence of neonatal jaundice
• 65% of term newborns develop clinical
jaundice in first week
• 80% of preterm infants
Types of neonatal jaundice
Bilirubin exists in two main forms in serum
1. Unconjugated bilirubin reversibly bound
to albumin
2. Conjugated bilirubin readily excretable via
the renal and biliary systems
Causes of neonatal jaundice
Best classified by age of onset and duration:
1. Early: within 24 hrs of life
2. Intermediate: 2 days to 2 weeks
3. Late: persists for >2 weeks
Causes of neonatal jaundice
Early
Intermediate
Late/prolonged
• Haemolytic causes:
• Physiological jaundice
• Conjugated (dark urine, pale
stools):
– Rh isoimmunisation
– ABO incompatibility
– G6PD deficiency
• Congenital infection
• Breast milk jaundice
(inadequate intake)
– Bile duct obstruction
• Sepsis
– Biliary atresia
• Haemolysis
– Neonatal hepatitis
• Crigler-Najjar syndrome
(glucuronyl transferase
absent/reduced)
• Polycythaemia, bruising
• Unconjugated:
– Physiological
– Breast milk jaundice
– Infection
– Hypothyroidism
Causes of neonatal jaundice
Early
Intermediate
Late/prolonged
• Haemolytic causes:
• Physiological jaundice
• Conjugated (dark urine, pale
stools):
– ABO incompatibility
• Breast milk jaundice
(inadequate intake)
– G6PD deficiency
• Sepsis
– Biliary atresia
• Haemolysis
– Neonatal hepatitis
– Rh isoimmunisation
• Congenital infection
• Crigler-Najjar syndrome
(glucuronyl transferase
absent/reduced)
• Polycythaemia, bruising
– Bile duct obstruction
• Unconjugated:
– Physiological
– Breast milk jaundice
– Infection
– Hypothyroidism
Early jaundice
• Apparent before 24 hours of age
• Always pathological
• The main cause for early jaundice is
haemolysis such as:
– Rhesus isoimmunisation
– ABO incompatibility
– G6PD deficiency
Investigations for early jaundice
•
•
•
•
•
•
Serum bilirubin level
FBC and film
Blood group
Maternal blood group
Direct coombs test
Consider G6PD level
Causes of neonatal jaundice
Early
Intermediate
Late/prolonged
• Haemolytic causes:
• Physiological jaundice
• Conjugated (dark urine, pale
stools):
– ABO incompatibility
• Breast milk jaundice
(inadequate intake)
– G6PD deficiency
• Sepsis
– Biliary atresia
• Haemolysis
– Neonatal hepatitis
– Rh isoimmunisation
• Congenital infection
• Crigler-Najjar syndrome
(glucuronyl transferase
absent/reduced)
• Polycythaemia, bruising
– Bile duct obstruction
• Unconjugated:
– Physiological
– Breast milk jaundice
– Infection
– Hypothyroidism
Physiological jaundice
• Physiological jaundice is jaundice that is present
between day 2 and day 10
Physiological jaundice
• Physiological jaundice is due to:
- High bilirubin production (fetal Hb,
high Hb)
- Reduced
bilirubin
excretion
(UDPGT concentrations at term are
1% of adult concentrations)
What are the factors that
exacerbate ‘physiological
jaundice’?
Factors that can increase the
severity of physiological jaundice
•
•
•
•
•
•
•
•
Prematurity
Sepsis
Bruising
Cephalohematoma
Polycythaemia
Delayed passage of meconium
Breast feeding
Certain ethnic groups, esp Chinese
Causes of neonatal jaundice
Early
Intermediate
Late/prolonged
• Haemolytic causes:
• Physiological jaundice
• Conjugated (dark urine, pale
stools):
– ABO incompatibility
• Breast milk jaundice
(inadequate intake)
– G6PD deficiency
• Sepsis
– Biliary atresia
• Haemolysis
– Neonatal hepatitis
– Rh isoimmunisation
• Congenital infection
• Crigler-Najjar syndrome
(glucuronyl transferase
absent/reduced)
• Polycythaemia, bruising
– Bile duct obstruction
• Unconjugated:
– Physiological
– Breast milk jaundice
– Infection
– Hypothyroidism
Prolonged Jaundice
• Jaundice persisting after 14 days in the
term infants
Or
• Jaundice persisting after 21days in the
preterm infant
When to start phototherapy?
Investigations for prolonged jaundice
• Serum bilirubin level
• Conjugated fraction of bilirubin
•
•
•
•
•
•
•
•
Liver function test (GGT, ALT, AST, Albumin)
Coagulation profile (PT, PTT, INR)
Abdominal ultrasound (gallbladder)
DISIDA / HIDA scan (with follow through)
Thyroid function test (TSH, free T4)
Metabolic screen (urine for reducing substance)
Hepatitis screen (TORCH)
Liver biopsy (bile duct proliferation)
•
FBC and film
•
Blood group
•
Maternal blood group
•
Direct coombs test
Kernicterus
• Also called bilirubin encephalopathy
• Neurological syndrome resulting from neurotoxic
affects of unconjugated bilirubin on basal
ganglia and brainstem nuclei
• Though infrequent, has at least 10% mortality
and 70% morbidity
Mechanism of neurotoxicity in
kernicterus
•
Unbound (unconjugated) bilirubin is:
– neurotoxic at high levels
– lipophilic and can cross the blood-brain-barrier
Bilirubin accumulates at nerve terminals
Binds to cell components
Impairs mitochondrial functions
neurotransmitter synthesis
Dysfunction and death of neurons
Bilirubin staining of affected areas
Long term clinical sequelae
Kernicterus: signs and symptoms
(first 24 hours)
• Phase 1:
– Poor suck, hypotonia and lethargy
• Phase 2:
– Hypertonia and opisthotonos
• Phase 3:
– Less hypertonia, high pitched cry, hearing
and visual loss, poor feeding and athetosis
Kernicterus: signs and symptoms
(long term)
• Choreoathetoid cerebral palsy
• Upward gaze palsy
• Sensorineural hearing loss
• Intellectual delay (less common)
Treatment of Neonatal Jaundice
• Depends on the cause and level and type of
bilirubin
• Unconjugated hyperbilirubinaemia:
–
Ensure adequate fluid intake
–
Phototherapy
–
IV immunoglobulin
–
Exchange transfusion
• Conjugated hyperbilirubinaemia:
–
Ensure adequate nutrition
–
Treat underlying problem
Phototherapy
Biliblanket
Phototherapy
lights
Phototherapy
Ultraviolet light
(10 – 400 nm)
Phototherapy is NOT:
• Ultraviolet light
• Infrared light
Spectrum of light
Blue is most effective (460 - 490 nm)
Bilirubin absorbance
Bilirubin absorbance and transmittance
Maisels MJ et al. N Engl J Med 2008;358:920-8
Infrared light
(400 – 700 nm)
When to start phototherapy?
Decision is based on:
1. Level of bilirubin
2. Rate of rise of bilirubin
3. Gestational age
4. Chronological age
5. Wellness of the baby
When to start phototherapy?
Take home message
• Jaundice
before
24
hours
is
always
pathological
• Kernicterus is rare but serious complication of
Unconjugated hyperbilirubin
• Early diagnosis of biliary atresia impacts on
long-term outcome
Examination of the hips Recommendations
• All newborns are to be screened by physical
examination (AAP)
– properly trained health care provider with regular reassessment of skills
– evidence is good, expert consensus is strong
– pre term babies at d/c health check or when acute needs
have settled
• Examination at 2-4 days, 1, 2, 4, 6, 9 & 12
months - (CTFPHC)
– fair evidence
Examination of the hips
• Be aware of changes of physical exam with age
– by 8-12 weeks Barlow & Ortolani tests are negative regardless of
the status of the femoral head
– at 3 months limitation of abduction is the most reliable sign
associated with DDH (AAP). Asymmetry of thigh folds, leg length
discrepancy & Galeazzi sign are also signs.
• Hips continue to dislocate through out the first
year of life
• 1/5000 children have a dislocated hip detected
at 18 months
Examination of the hips – High
Risk
• Family history
• Breech presentation
• Foot deformities
• Oligohydramnios
• Primiparity
• Females
Examination of the hips Incidence
• White neonates: 1% CDH
• Varies with Race:Blacks/Koreans/Chinese
•F:M
•LHS
•RHS
•Bilat
4:1
60%
20%
20%
Examination of the hips
Identify at Risk infants:
Examine the Hips for Dislocation and/or dislocatibility
• If hips are stable and there are no risk factors  no further action
• If there is a strong family history (parents or siblings) of CDH,
delivery was as breech, or other deformities are present:
 hip ultrasound at 6 weeks and appointment at the post-natal clinic
even if hips are stable during the immediate postnatal period.
• All babies with clicky hips MUST be reviewed by the Neonatal
Registrar and NOT simply referred for U/S and follow-up. Clicky
but stable hips are quite common in the first 48 hours of life!
Heart Examination
• Congenital heart disease (CHD) commonest congenital
malformation (9 in 1000 live births)
• Contributes significantly to infant mortality and morbidity.
• Current post-natal screening CHD: physical examination
after birth and repeat examination at 6-8weeks of age.
• Can miss up to 25% of infants with critical CHD
• Delayed or missed diagnosis associated with significant
morbidity, the most significant being hypoxic / ischaemic
brain injury.
Heart Examination
• Observational studies suggest that there
may be some benefit in screening with pulse
oximetry
• To date no randomised controlled trials
• Rarity of undiagnosed cyanotic CHD and
large number of patients required for studies
a randomised controlled trial may not be
feasible.
Heart Examination
• Systematic reviews found overall sensitivity
of 63% and specificity of 99.8% for pulse
oximetry in diagnosing congenital heart
disease in asymptomatic newborns
• False positives 0.2-0.9%
• Sensitivity of pulse oximetry screening 72%
compared to 58% for clinical examination.
Heart Examination
• 2 other studies found that in asymptomatic babies
a significantly higher number of babies with duct
dependent heart disease were detected during
screening by physical examination and pulse
oximetry (86.2%) compared with those regions
not using pulse oximetry screening (72%).
 benefit of screening with pulse oximetry in
addition to clinical examination. False positives
for congenital heart disease will occur but may be
expected to detect some other important medical
problems, such as sepsis or RDS
Heart Examination
PULSE OXIMETRY SCREENING
• Within 4-24 hours of life on PNW or DS
If SaO2 < 90%
• Medical review
• If asymptomatic, repeat pulse oximetry in 23 hours
• If symptomatic further investigations
(bloods, CXR, ECG and echocardiography),
consider admission)
Heart Examination
• Screening introduced to TCH 12 months
ago
• Audit after 4 months (976 neonates)
Heart Examination
• 40 (4%) of infants were missed
• 15 (1.5%) were found to have saturations<90%
– 3 (0.3%) incorrect assignment
– 7 (0.7%) -passed on screen 2
– 1 (0.1%) other diagnosis (Pierre Robin sequence)
• 4 (0.41%) failed both screens
– 3 (0.31%) had sepsis with normal sats on discharge
– 1 (0.1%) had PPHN and non critical congenital heart
defect (ASD)
•
Take home messages
•
•
•
•
Nutrition (weight, urine output)
Jaundice
Physical exam (heart, hips)
We are just at the end of the phone!!!!!
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