Management of Dilated Pupils After a Seizure
The immediate management of a patient with dilated pupils after a seizure should include assessment for signs of increased intracranial pressure, airway management, and administration of appropriate anticonvulsants if seizures continue. 1, 2
Initial Assessment
- Perform rapid neurological assessment focusing on pupil size, symmetry, reactivity to light, level of consciousness, brainstem reflexes, and motor responses 2
- Monitor for other signs of deterioration including ipsilateral pupillary dysfunction, adduction paralysis, worsening limb power, and abnormal respiratory patterns 1
- Frequently monitor level of arousal and ipsilateral pupillary dilation as these may indicate deterioration 1
- Evaluate for potential causes of dilated pupils including post-ictal state, medication effects, or increased intracranial pressure 3
Emergency Management
- Establish and maintain a patent airway - equipment for this should be immediately available 4
- Elevate head of bed to 30° to improve venous drainage 2
- If seizures are ongoing, administer lorazepam 4 mg IV slowly (2 mg/min) for adults 4
- If seizures continue after 10-15 minutes, an additional 4 mg IV dose may be administered 4
- For persistent seizures after benzodiazepines and phenytoin, consider high-dose phenytoin, phenobarbital, valproic acid, midazolam infusion, pentobarbital infusion, or propofol infusion 1
Diagnostic Workup
- If signs of increased intracranial pressure are present (declining consciousness, focal neurology, unequal/dilated/poorly responsive pupils), urgent neuroimaging is indicated 1, 2
- Consider EEG testing if there is persistent altered consciousness to rule out nonconvulsive status epilepticus 1
- Temperature should be monitored as part of vital sign assessments; ideally every 4 hours for the first 48 hours 1
- For temperature >37.5°C, increase monitoring frequency and investigate possible infection 1
Management Based on Cause
If Due to Increased Intracranial Pressure:
- Administer osmotic therapy immediately (mannitol 0.5 mg/kg infused rapidly over 5-10 minutes) 1, 2
- Rapid induction of anesthesia, tracheal intubation, and mechanical ventilation may be necessary 1
- Keep PCO₂ within normal range to stabilize cerebral blood flow 1
- Avoid hyperventilation except in cases of imminent cerebral herniation 2
If Due to Post-ictal State:
- Monitor for recovery of pupillary function as post-ictal mydriasis is typically transient 5
- Continue to monitor vital signs and neurological status 1
- A single, self-limiting seizure occurring at the onset or within 24 hours after an ischemic stroke should not be treated with long-term anticonvulsant medications 1
If Due to Medication Effect:
- Consider possible medication causes (high-dose dopamine, anticholinergics, antihistamines) 6, 3
- Fixed, dilated pupils can occur with certain medications and may not necessarily indicate poor neurological status 7, 6
Special Considerations
- Prophylactic use of anticonvulsant medications in patients with ischemic stroke is not recommended and may have negative effects on neurological recovery 1
- Seizures are uncommon after a hemispheric infarct, but any patient with a fluctuating level of consciousness may require more prolonged EEG monitoring 1
- In pediatric patients, seizures are a common presentation with stroke - consider enhanced EEG monitoring in at-risk populations 1
- Fixed, dilated pupils are a grave prognostic sign following traumatic brain injury, with 72% of survivors experiencing ophthalmological deficits 8
Monitoring and Follow-up
- Continuous monitoring of pupillary size and reactivity, level of consciousness, vital signs, and frequent reassessment of neurological status 2
- For patients with stroke, rehabilitation therapy should begin as early as possible once the patient is medically stable 1
- Patients who have had a seizure should be monitored for recurrent seizure activity during routine monitoring of vital signs and neurological status 1