Guide to Neurological Assessment (Glasgow Coma Scale)

Accurate neurological assessment detects early signs of deterioration. The Neurological Assessment monitors brain function through systematic evaluation of consciousness, cranial nerves, and motor response. Central to this is the Glasgow Coma Scale (GCS), the global standard for quantifying consciousness. Mastering GCS scoring and cranial nerve checks is critical for identifying Increased Intracranial Pressure (ICP) and stroke. This guide details the protocols for rigorous neuro monitoring.

Assessment Components

A comprehensive neuro exam evaluates Mental Status, Cranial Nerves, Motor System, Sensory System, and Reflexes. In acute settings, nurses prioritize the rapid assessment of Level of Consciousness (LOC) and pupillary response.

The National Center for Biotechnology Information (NCBI) identifies consistent GCS monitoring as the strongest predictor of outcomes in traumatic brain injury.

Glasgow Coma Scale (GCS)

The GCS scores responsiveness across three domains. Scores range from 3 (Deep Coma) to 15 (Fully Alert).

1. Eye Opening (4 Points)

Assess the stimulus required to open eyes.

• 4 – Spontaneous: Eyes open without stimulus.
• 3 – To Sound: Eyes open to verbal command (normal or loud voice).
• 2 – To Pressure: Eyes open only to physical pressure (e.g., nail bed pressure, trapezius squeeze).
• 1 – None: No eye opening despite pressure.

2. Verbal Response (5 Points)

Assess content and coherence.

• 5 – Oriented: Correctly identifies Person, Place, Time, and Situation.
• 4 – Confused: Speaks in sentences but answers are incorrect/disoriented.
• 3 – Inappropriate Words: Random, intelligible words unrelated to questions.
• 2 – Sounds: Incomprehensible moans or groans.
• 1 – None: No vocalization.

3. Motor Response (6 Points)

Assess the best motor response to command or pressure.

• 6 – Obeys Commands: Follows 2-step requests (e.g., “Squeeze my hand, now let go”).
• 5 – Localizes Pain: Purposeful movement toward the pain source (hand moves above clavicle to remove stimulus).
• 4 – Normal Flexion (Withdrawal): Pulls extremity away from pain quickly.
• 3 – Abnormal Flexion (Decorticate): Arms flex slowly toward the core; legs extend. Indicates hemispheric damage.
• 2 – Extension (Decerebrate): Arms extend, adduct, and pronate. Indicates brainstem damage.
• 1 – None: Flaccid paralysis.

Pupillary Assessment (PERRLA)

Pupils indicate intracranial pressure dynamics and brainstem function.

• Size: Measure in millimeters (2-5mm normal). Pinpoint (opiates/pontine damage) vs. Dilated (herniation/stimulants).
• Shape: Round. Irregular shapes suggest trauma or surgery.
• Reaction: Direct (illuminated eye constricts) and Consensual (opposite eye constricts).
• Accommodation: Constriction when focus shifts from far to near.

Anisocoria (unequal pupils >1mm difference) requires immediate reporting if new.

Rapid Cranial Nerve Assessment

In acute care, assess key nerves to detect subtle changes.

• CN II (Optic) / CN III (Oculomotor): Pupillary reaction.
• CN VII (Facial): Smile/frown symmetry. Asymmetry suggests stroke (Bell’s Palsy affects forehead; stroke spares forehead).
• CN IX/X (Glossopharyngeal/Vagus): Gag reflex and swallow. Essential before oral intake.
• CN XII (Hypoglossal): Tongue protrusion (midline).

Motor & Sensory Function

Compare left and right sides for symmetry.

Motor Grading (0-5)

• 5: Active movement against full resistance.
• 3: Active movement against gravity only.
• 1: Flicker of contraction.
• 0: No movement.

Pronator Drift: Patient holds arms out, palms up, eyes closed. If one arm drifts down/pronates, it indicates subtle weakness (stroke sign).

Reflexes

Babinski Reflex: Stroke sole of foot.
Normal (Adult): Toes curl down.
Abnormal: Big toe dorsiflexes (fans up). Indicates Upper Motor Neuron lesion.

Increased Intracranial Pressure (ICP)

Recognize the progression of ICP symptoms.

• Early Signs: Change in LOC (restlessness, confusion), headache.
• Late Signs (Cushing’s Triad):
  • Hypertension: Widening pulse pressure (Systolic rises to perfuse brain).
  • Bradycardia: Vagus nerve stimulation due to high pressure.
  • Irregular Respirations: Brainstem compression (Cheyne-Stokes).

Review vital sign norms in our Head-to-Toe Assessment Guide.

Documentation Standards

Document trends precisely. Avoid vague terms like “lethargic.”
Example: “GCS 13 (E3, V4, M6). Pupils 3mm brisk bilateral. Right arm weakness 4/5. Pronator drift positive right. Dr. Smith notified of change from baseline GCS 15.”

Neuro Assessment FAQs

Conclusion

Neurological assessment requires vigilance. Mastering the GCS and recognizing ICP trends allows nurses to intervene before permanent brain damage occurs. These skills are fundamental to trauma and critical care nursing.