Transcript Neonatal Jaundice
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 bilirubin and excreted.
is then converted to
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:
– Rh isoimmunisation – ABO incompatibility – G6PD deficiency • Congenital infection •
Physiological jaundice
• Breast milk jaundice (inadequate intake) •
Sepsis
• Haemolysis • Crigler-Najjar syndrome (glucuronyl transferase absent/reduced) • Polycythaemia, bruising •
Conjugated
(dark urine, pale stools): – Bile duct obstruction – –
Biliary atresia Neonatal hepatitis
•
Unconjugated
: –
Physiological
–
Breast milk jaundice
– Infection –
Hypothyroidism
Causes of neonatal jaundice Early Intermediate Late/prolonged
•
Haemolytic causes:
– Rh isoimmunisation – ABO incompatibility – G6PD deficiency • Congenital infection •
Physiological jaundice
• Breast milk jaundice (inadequate intake) •
Sepsis
• Haemolysis • Crigler-Najjar syndrome (glucuronyl transferase absent/reduced) • Polycythaemia, bruising •
Conjugated
(dark urine, pale stools): – Bile duct obstruction – –
Biliary atresia Neonatal hepatitis
•
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:
– Rh isoimmunisation – ABO incompatibility – G6PD deficiency • Congenital infection •
Physiological jaundice
• Breast milk jaundice (inadequate intake) •
Sepsis
• Haemolysis • Crigler-Najjar syndrome (glucuronyl transferase absent/reduced) • Polycythaemia, bruising •
Conjugated
(dark urine, pale stools): – Bile duct obstruction – –
Biliary atresia Neonatal hepatitis
•
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:
– Rh isoimmunisation – ABO incompatibility – G6PD deficiency • Congenital infection •
Physiological jaundice
• Breast milk jaundice (inadequate intake) •
Sepsis
• Haemolysis • Crigler-Najjar syndrome (glucuronyl transferase absent/reduced) • Polycythaemia, bruising •
Conjugated
(dark urine, pale stools): – Bile duct obstruction – –
Biliary atresia Neonatal hepatitis
•
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
ganglia and brainstem nuclei bilirubin on basal • 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
Biliblanket Phototherapy Phototherapy lights
Ultraviolet light
(10 – 400 nm)
Phototherapy
Phototherapy is NOT:
•
Ultraviolet light
•
Infrared light
Spectrum of light
Blue is most effective (460 - 490 nm)
Bilirubin absorbance Infrared light
(400 – 700 nm)
Bilirubin absorbance and transmittance
Maisels MJ et al.
N Engl J Med
2008;358:920-8
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 pathological before 24 hours is always • 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 re assessment 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 2 3 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!!!!!