Glasgow Coma Scale (GCS)

Definition

The Glasgow Coma Scale (GCS) is a clinical scale used to reliably measure a person's level of consciousness after a brain injury. It scores three components: eye opening, verbal response, and motor response.

Components and Scoring

• Eye Opening (1-4): 4=spontaneous, 3=to voice, 2=to pain, 1=none.
• Verbal Response (1-5): 5=oriented, 4=confused, 3=inappropriate words, 2=incomprehensible sounds, 1=none.
• Motor Response (1-6): 6=obeys commands, 5=localizes pain, 4=withdraws from pain, 3=flexion (decorticate), 2=extension (decerebrate), 1=none.

Total Score Interpretation

• 13 to 15: Mild brain injury
• 9 to 12: Moderate brain injury
• 3 to 8: Severe brain injury (typically requires intubation if 8 or less)
• 3: Deep coma or death

Nursing Considerations

Document each component separately (e.g., 'GCS 10: E2 V3 M5'). Reassess every 1 to 4 hours in neuro patients, or more frequently if deteriorating. A drop of 2 or more points is clinically significant. If GCS falls to 8 or below, prepare for airway management.

Pediatric GCS

A modified GCS exists for infants and young children who cannot speak, using different verbal response criteria.

NCLEX Relevance

GCS is tested in neuro, trauma, and critical care scenarios. Know the 'GCS 8, intubate' rule and recognize decorticate vs decerebrate posturing.