Hypoxic Ischaemic Encephalopathy

Question 1

What causes hypoxic ischaemic encephalopathy?

Answer 1

Hypoxia during birth

Question 2

What is hypoxia?

Answer 2

A lack of oxygen

Question 3

What is ischaemia?

Answer 3

A restriction in blood flow to the brain

Question 4

What is encephalopathy?

Answer 4

Malfunctioning of the brain

Question 5

What can HIE lead to?

Answer 5

Permanent damage to the brain, causing cerebral palsy.

Question 6

What can severe HIE lead to?

Answer 6

Death

Question 7

What can cause HIE?

Answer 7

Anything that leads to asphyxia to the brain can cause HIE.

Question 8

What is asphyxia?

Answer 8

Deprivation of oxygen

Question 9

What are possible causes of HIE?

Answer 9

• Maternal shock
• Intrapartum haemorrhage
• Prolapsed cord, causing compression of the cord during birth
• Nuchal cord

Question 10

What is nuchal cord?

Answer 10

The cord is wrapped around the neck of the baby

Question 11

What is the name of the grading scale used for HIE?

Answer 11

Sarnat Staging

Question 12

What are the features of Mild HIE?

Answer 12

• Poor feeding, generally irritability and hyper-alert
• Resolves within 24 hours
• Normal prognosis

Question 13

What are the features of moderate HIE?

Answer 13

• Poor feeding, lethargic, hypotonic and seizures
• Can take weeks to resolve
• Up to 40% develop cerebral palsy

Question 14

What do 40% of neonates with moderate HIE develop?

Answer 14

Cerebral palsy

Question 15

What are the features of severe HIE?

Answer 15

• Reduced consciousness, apnoeas, flaccid and reduced or absent reflexes
• Up to 50% mortality
• Up to 90% develop cerebral palsy

Question 16

What percentage of neonates with severe HIE develop cerebral palsy?

Answer 16

90%

Question 17

What percentage of neonates with severe HIE die?

Answer 17

50%

Question 18

What is the management of HIE?

Answer 18

Supportive care

Question 19

What does supportive care for HIE include?

Answer 19

Neonatal resuscitation 
Ongoing optimal ventilation
Circulatory support
Nutrition
Acid base balance 
Treatment of seizures.

Question 20

What is an option for neonates with HIE to prevent against hypoxic brain damage?

Answer 20

Therapeutic hypothermia

Question 21

What does therapeutic hypothermia involve?

Answer 21

Actively cooling the core temperature of the baby according to a strict protocol.

Question 22

How is the temperature of the baby monitored with therapeutic hypothermia?

Answer 22

Carefully monitored with a target of between 33 and 34°C, measured using a rectal probe.

Question 23

How long is therapeutic hypothermia carried out?

Answer 23

72 hours

Question 24

What is the mechanism of action of therapeutic hypothermia?

Answer 24

Reduces inflammation and neurone loss after the acute hypoxic injury.

Question 25

What diseases can therapeutic hypothermia reduce the risk of?

Answer 25

Cerebral palsy
Developmental delay
Learning disability
Blindness and death.