Chapter 11 Selected Diseases and Disorders of the Nervous System
11p5 Glasgow Coma Scale (GCS)
Zoë Soon
Purpose
- Used to quantify the level of consciousness in patients with brain injury.
- Guides clinical decisions and monitors progression or improvement.
Assessment Criteria:
- Eye-Opening
- Motor Response
- Verbal Response
Scoring Range
- Lowest score: 3 (deep coma or unresponsive)
- Highest score: 15 (fully alert)
1. Eye Opening (Score 1–4) – FYI
| Response | Score | Description |
| Spontaneous | 4 | Eyes open on their own. |
| Response to speech | 3 | Eyes open when called or stimulated. |
| Response to pain | 2 | Eyes open when painful stimulus applied. |
| None | 1 | No eye opening, unresponsive. |
2. Motor Response (Score 1–6) – FYI
| Response | Score | Description |
| Obeys commands | 6 | Follows instructions (e.g., raise arm). |
| Localizes pain | 5 | Attempts to move toward painful stimulus. |
| Normal flexion (decorticate) | 4 | Flexes limbs in response to pain. |
| Abnormal flexion (decerebrate) | 3 | Arms extended with abnormal posturing. |
| Extension (flaccid) | 2 | No purposeful movement; limp. |
| None | 1 | No response, flaccid. |
Note:
- Decorticate (damage to both cerebral cortexes): Flexed arms, clenched fists.
- Decerebrate (damage to brainstem): Extended arms and legs, abnormal rigidity.
- Opisthotonos (damage to extrapyramidal tract): spastic paralysis in spinal muscles (rigid, arched back)
3. Verbal Response (Score 1–5) – FYI
| Response | Score | Description |
| Oriented | 5 | Fully alert, knows time and place. |
| Confused | 4 | Responds appropriately but confused. |
| Inappropriate words | 3 | Random or nonsensical speech. |
| Incomprehensible sounds | 2 | No meaningful words, speaking gibberish. |
| None | 1 | No verbal response. |
Interpretation of Scores – FYI
- 13–15: Mild injury, typically concussion or brief unconsciousness.
- 9–12: Moderate injury, recovery possible.
- 3–8: Severe injury, deep coma, high risk of death.
- 3: Deep coma, no response.
Prognostic Indicators
- Higher scores correlate with better outcomes.
- Scores 4–8: Usually indicate coma; survival rate around 20-40%.
- Scores above 9: Better chance of recovery, less severe brain damage.
Monitoring
- GCS should be assessed frequently (every 2 hours or more).
- Helps track clinical progress or deterioration.
Summary
- The GCS provides a standardized assessment of brain function.
- Helps determine severity of brain injury.
- Critical in guiding treatment plans and prognosis.
