Glasgow Coma Scale
Assesses level of consciousness via eye, verbal, and motor responses
How to use & interpret
The Glasgow Coma Scale grades conscious level from 3 to 15 across eye-opening (1–4), verbal (1–5) and motor (1–6) responses. Always record the three components separately (e.g. E3V4M5), as the breakdown carries more information than the total and the motor score is the most prognostic.
A GCS ≤8 indicates coma and should prompt urgent assessment of airway protection. A drop of ≥2 points is significant deterioration. Score the best response, note confounders (sedation, intubation, intoxication, aphasia), and use the FOUR score where the verbal score cannot be assessed (e.g. intubated patients).
Score interpretation
GCS 15 — Normal consciousness
→ No immediate concern from GCS alone
GCS 13–14 — Minor impairment
→ Close observation; identify and treat cause
GCS 9–12 — Moderate impairment
→ Urgent assessment; CT head; continuous monitoring
GCS ≤8 — Severe impairment / coma
→ GCS ≤8: consider intubation and airway protection
Interpretation bands for the GCS. Apply clinical judgement and local guidance.
Frequently asked questions
Does GCS ≤8 always mean intubate?
It is a widely used trigger to assess the need for airway protection, but the decision is clinical — based on the trajectory, gag/cough, cause, and setting — not on the number alone.
References
- Teasdale G, Jennett B. Assessment of coma and impaired consciousness. Lancet. 1974;2(7872):81–4.
Related
Curated clinical cross-links plus same-class fallbacks.
- Tranexamic Acid (ICU/Trauma/Surgical) · Antifibrinolytic
- Cetuximab · Anti-EGFR Monoclonal Antibody — Head and Neck Cancer
- Cisplatin · Platinum Chemotherapy — Head and Neck Cancer
- Methotrexate · Chemotherapy / Immunosuppressant — Head and Neck / Granulomatosis
- Pembrolizumab (Head and Neck SCC) · PD-1 Inhibitor
- Nivolumab (Head and Neck SCC) · PD-1 Inhibitor
Featured in these MRCEM clinical pathways
The GCS is covered in detail — with RCEM/NICE evidence base, indications and pitfalls — in the following exam-focused pathways on our sister siteReviseMRCEM.
MRCEM Primary / Intermediate / OSCE candidates: each pathway includes exam-style questions, RCEM/NICE citations, and FAQ summaries.
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.