Coma and Glasgow Coma Scale in Children
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Direct answer
Coma is a state of unarousable unresponsiveness with no purposeful response to stimuli. The Glasgow Coma Scale grades eye, verbal and motor responses on a total from 3 to 15, using a modified verbal score for children under two years. A score of 8 or less conventionally prompts airway protection, while hypoglycaemia, hypoxia and seizures are reversible causes to correct first.
What you must remember
- Glasgow Coma Scale: eye opening scored 1 to 4, best verbal response 1 to 5 and best motor response 1 to 6, giving a total from 3 to 15.
- Infant verbal modification: under two years, the verbal score uses coos and babbles, irritable cry and cries to pain, because oriented speech is not yet possible.
- Airway threshold: a score of 8 or less generally calls for airway protection and consideration of intubation.
- Reversible causes: hypoglycaemia, hypoxia, seizures, poisoning and hyperammonaemia, all checked early.
- Pupillary signs: a unilateral fixed dilated pupil suggests uncal herniation from a mass lesion or raised pressure.
- Immediate tests: capillary glucose, blood gas, electrolytes and toxicology, with ammonia where a metabolic cause is suspected.
- Sequence: airway, breathing and circulation come first, and neuroimaging follows once the child is stable.
A stepwise approach to the comatose child
A comatose child is a medical emergency in which airway and circulation take priority over the neurological diagnosis. The steps below follow the usual paediatric sequence, with investigations added once the child is stabilised.
- Secure airway and breathing: open the airway, give high-flow oxygen and decide on intubation using the Glasgow Coma Scale score, gag reflex and breathing effort. Aspiration is a constant risk in an unresponsive child.
- Stabilise circulation: establish intravenous access, correct hypotension and give fluid boluses cautiously. Shock and cerebral hypoperfusion worsen brain injury.
- Check glucose immediately: measure capillary glucose and correct hypoglycaemia with intravenous dextrose, since it is the quickest reversible cause to exclude.
- Assess the neurological state: record the score, pupils, posture and any seizure activity. Treat seizures promptly with an anti-seizure drug.
- Look for raised pressure: keep the head elevated, avoid hypotonic fluids and use hyperosmolar therapy if herniation signs appear.
- Investigate the cause: send blood gas, electrolytes, toxicology, ammonia and infection screens, and image the brain once the child is stable.
- Refer early: transfer to a paediatric intensive care unit, because neuro-critical care needs specialist monitoring.
Where the exam tries to catch you
Coma questions often test the scoring rules and the order of management.
- Trap: scoring the verbal response of a six-month-old as oriented speech Correct: under two years, the infant verbal scale uses coos, babbles or an irritable cry.
- Trap: imaging a comatose child before checking glucose Correct: hypoglycaemia is quick to check and reversible, so glucose comes before any scan.
- Trap: delaying airway protection in a child with a score of 8 Correct: a score of 8 or less generally calls for airway protection because the reflexes are unreliable.
- Trap: starting prolonged hyperventilation routinely for raised pressure Correct: brief hyperventilation is reserved for herniation, because prolonged hyperventilation reduces cerebral perfusion.
Frequently asked questions
What is the range of the Glasgow Coma Scale in children?
The Glasgow Coma Scale ranges from 3 to 15 in children, as in adults. A score of 3 indicates no response, while 15 indicates full alertness, with a modified verbal component used under two years.
How is the verbal score modified for infants in the Glasgow Coma Scale?
In children under two years, the verbal score uses coos and babbles, irritable cries, cries to pain, moans to pain and no response. This modification replaces oriented speech, which infants cannot yet produce.
What Glasgow Coma Scale score usually prompts airway protection in a comatose child?
A Glasgow Coma Scale score of 8 or less usually prompts airway protection and consideration of intubation in a comatose child. The decision also weighs breathing effort, the gag reflex and the risk of aspiration.
Which reversible causes of coma must be checked first in children?
Hypoglycaemia, hypoxia, seizures, poisoning and hyperammonaemia are reversible causes of coma that must be checked first in children. Blood glucose and blood gas are measured immediately, since correcting them can restore consciousness quickly.
Why must hyperventilation be used cautiously in a child with raised intracranial pressure?
Hyperventilation must be used cautiously in a child with raised intracranial pressure because prolonged hyperventilation reduces cerebral blood flow and can worsen ischaemia. It is reserved for signs of impending herniation, and then only briefly.