EM · Coma
Coma and GCS assessment
Also known as GCS · Altered conscious level · Decreased conscious state · Unconscious patient
The comatose patient and the Glasgow Coma Scale — the structured approach (the ABCDE, the rapid glucose, the reversible causes), the GCS (the eye, the verbal, the motor components; the best motor response is the most sensitive), the AVPU for the rapid triage, the differential (the toxic-metabolic, the structural, the infectious), the immediate investigations (the glucose, the blood gas, the CT, the drug screen), and the management (the airway, the naloxone, the thiamine, the specific antidote). ACEM-primary, globally tagged.
Checked against its sources on 13 Oct 2026
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Target exams
Red flags
- The hypoglycaemia is the commonest rapidly reversible cause of the coma — check the glucose immediately in every comatose patient
- The opioid overdose (the pin-point pupils, the reduced respiratory rate) responds to naloxone titrated to ventilation — give it early
- A comatose patient with the asymmetric pupils or the unilateral weakness has a structural intracranial lesion until proven otherwise
- The alcoholic patient may have the Wernicke encephalopathy — give thiamine before the glucose
Meet the patient
A 58-year-old man is found unconscious at home, brought in by ambulance. His eyes open only to the supraorbital press, he makes no sound, the right arm withdraws to a supraorbital press while the left arm extends rigidly with adduction and internal rotation. The glucose is 6.4, the pupils 3 mm and briskly reactive, the respiratory rate 6. The story is not yet told by the history — it is told by the asymmetric motor response, and it points at a structural intracranial lesion until the CT says otherwise.[1]
The two questions that govern every coma are two first five minutes answer: is there a rapidly reversible cause? (the glucose, the opioid, the thiamine) and is this toxic-metabolic or structural? (the pupils decide — equal and reactive is metabolic, asymmetric or fixed is structural). Hold those two and everything below slots into place.[1]
References26ShowHide
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