What is the management for a patient with concussion and pupil dilation?

Management of Pupil Dilation in Concussion

In patients with concussion and pupil dilation, immediate neurological assessment and management is required as this may indicate rising intracranial pressure and impending herniation requiring emergent intervention.

Initial Assessment

• Frequently monitor level of arousal and pupillary changes in patients with concussion, as pupil dilation (particularly unilateral) may indicate deterioration and rising intracranial pressure 1

• Assess for other signs of neurological deterioration including:

  • Gradual development of midposition pupils 1
  • Worsening of motor responses 1
  • Changes in respiratory patterns 1
  • Development of new brainstem signs 1

• Evaluate for specific pupillary findings:

  • Unilateral pupil dilation (particularly ipsilateral to injury) may indicate uncal herniation 2
  • Fixed and dilated pupils suggest decreased brain stem blood flow (below 40 ml/100g/min) 2
  • Note that pupillary dilation can sometimes be falsely localizing 3

Immediate Management

• For patients showing signs of deterioration with pupillary dilation:

  • Elevate head of bed to 30° 1
  • Administer osmotic therapy (first-line intervention) 1, 4

• Osmotic therapy options:

  • Mannitol: 0.25 to 2 g/kg body weight as a 15% to 25% solution administered over 30-60 minutes 4
  • For pediatric patients: 1-2 g/kg body weight or 30-60 g/m² body surface area over 30-60 minutes 4
  • For small or debilitated patients: 500 mg/kg 4
  • Hypertonic saline is an alternative osmotic agent 1

• If pupil dilation persists despite medical management, consider urgent neurosurgical consultation for potential surgical intervention 5

Special Considerations

• In cases of fixed and dilated pupils with preserved consciousness, still treat as a neurological emergency as this can indicate rising intracranial pressure requiring immediate intervention 5

• Monitor for signs of brainstem compression which may accompany pupillary changes:

  • Bradycardia 1
  • Irregular breathing patterns 1
  • Sudden apnea 1

• For patients with suspected occludable angles, pupil dilation should be done with caution as it can precipitate angle closure 1

Monitoring and Follow-up

• Continuous monitoring of:

  • Pupillary size and reactivity 1
  • Level of consciousness 1
  • Vital signs 1
  • Neurological status 1

• Consider neuroimaging (CT scan) to evaluate for:

  • Cerebral edema 5
  • Midline shift 5
  • Intracranial hemorrhage 6
  • Subfalcine herniation 5

Pitfalls and Caveats

• Not all patients with herniation have fixed and dilated pupils, and not all patients with nonreactive, enlarged pupils have uncal herniation 2
• Pupillary dilation may be associated with decreased brain stem blood flow rather than just mechanical compression of the third cranial nerve 2
• Recent mild head injury (concussion) may increase risk for catastrophic pathology such as acute subdural hematoma 6
• Unilateral fixed dilation of the pupil may occasionally be falsely localizing (appearing on the side opposite to the lesion) 3
• Avoid hyperventilation except in cases of imminent cerebral herniation, and then only for short periods 1