Hypoxic Ischaemic Encephalopathy

Question 1

Risk factors for HIE

Answer 1

• failure of gas exchnage across placenta
  
  • excessive/ prolonged uterine contractions
  • placetal abruption
  • ruptured uterus
• interruption of umbilical blood flow
  
  • cord compression- shoulder dystocia
  • cord prolapse
• inadequte maternal placental perfusion
  
  • maternal HTN/ hypotension
  • IUGR
• comprimised fetus
  
  • anaemia
  • IUGR
• failure to breathe at birth- CVR adaptation failure

Question 2

Key clinical features of HIE

Answer 2

• Mild
  
  • ​irritable
  • responds to stimulation
  • staring of eyes
  • hyperventilation
  • impaired feeding
• Moderate
  
  • ​marked abnormalities of tone and movement
  • cannot feed
  • +/- seizures
• Severe
  
  • ​no normal spontaneous movement
  • no response to pain
  • hypotonia/ hypertonia of limbs
  • prolonged, refractory to Tx seizures
  • multi organ failure

Question 3

Management of HIE

Answer 3

• respiratory support
• aEEG
  
  • detect abnormal background features
  • identify seizures
  • encephalopathy
• anticonvulsants
• fluid restriction
  
  • trainsient renal impairment
• volume and ionotrope support
• tx of hypoglycaemia/ hypocalcaemia
• mild hypothermia (rectal temp of 33-34) for 72h reduces brain injury if started 6h after birth

Question 4

Long term developmental risks of HIE

Answer 4

• mild: complete recovery
• moderate:
  
  • excellent long term if clinical neuro full recovery/ feeding by 2 weeks
  • fulltime recovery unlikely if no neuro recovery
• severe
  
  • ​mortality 30-40%
  • 80 % neurodevelopmental disability
    
    • CP