Treatment of Atypical Posterior Reversible Encephalopathy Syndrome (PRES) and Post-Ictal Effects
The management of atypical PRES requires immediate identification and removal of triggering factors, discontinuation of offending medications, and very stringent blood pressure control as essential first-line interventions. 1
Immediate Management of PRES
Blood Pressure Control
- Target gradual blood pressure reduction to avoid cerebral hypoperfusion
- For severe hypertension (systolic BP ≥220 mmHg), use IV antihypertensives:
- First-line: IV labetalol
- Oral option: Nifedipine
- Second-line: IV hydralazine 1
Seizure Management
- For active seizures:
- Administer benzodiazepines for acute seizure control (lorazepam 0.1 mg/kg IV) 1, 2
- Follow with antiepileptic drugs:
- Levetiracetam (25 mg/kg) - 78% seizure control rate
- Phenytoin (20 mg/kg) - 68% seizure control rate
- Valproate (30 mg/kg) - 68% seizure control rate 2
- For refractory seizures, consider adding a second antiepileptic drug 2
Addressing Cerebral Edema
- Elevate head of bed to 30 degrees to decrease hydrostatic pressure and cerebral edema 1
- For evidence of cerebral edema or increased intracranial pressure:
- Administer hyperosmolar therapy:
- Mannitol: 0.5-1 g/kg IV initially, then 0.25-1 g/kg every 6 hours, or
- Hypertonic 3% saline: 5 ml/kg IV over 15 minutes, then 1 ml/kg/hour IV to target serum sodium 150-155 meq/l 1
- Consider hyperventilation to achieve PaCO2 of 30-40 mmHg for acute management of intracranial hypertension 1
- Monitor electrolytes every 4-6 hours 1
- Administer hyperosmolar therapy:
Management of Post-Ictal Effects
Immediate Post-Ictal Care
- Monitor patients for at least 24 hours for late seizures (tardive seizures) 3
- Obtain neurology consultation if recurrent prolonged seizures or tardive seizures occur 3
- For prolonged seizures (>180 seconds), administer additional methohexital, diazepam, or lorazepam 3
Treatment of Post-Ictal Symptoms
- For post-ictal headache, nausea, vomiting, muscle aches, confusion, and agitation:
- Manage conservatively as these usually do not persist beyond the day of the seizure 3
- For delirium:
- Nonpharmacologic interventions (reorientation, cognitive stimulation, sleep hygiene)
- Reduce or eliminate delirium-inducing medications (steroids, anticholinergics)
- For moderate delirium: oral haloperidol, risperidone, olanzapine, or quetiapine 3
- For severe delirium (agitation): haloperidol, olanzapine, or chlorpromazine 3
- For refractory agitation: add lorazepam to neuroleptics 3
Special Considerations for Atypical PRES
Discontinuation of Triggering Medications
- Immunosuppressants
- Chemotherapy agents
- Other offending medications 1
Management Based on Underlying Cause
- For eclampsia-related PRES: immediate delivery 1
- For autoimmune conditions: address underlying condition 1
- For chemotherapy-induced PRES: carefully consider reintroduction of anticancer therapy 1
Severe Cases with Refractory Intracranial Hypertension
- Consider decompressive craniectomy in severe cases with malignant cerebral edema
- Decision should be based on risk-benefit discussion between the multidisciplinary medical team and patient surrogate 1
Monitoring and Follow-up
EEG Monitoring
- EEG findings in PRES are diverse, including:
- Normal EEG
- Intermittent or continuous generalized slowing
- Background slowing or suppression
- Generalized rhythmic delta activity
- Spike/sharp-wave discharges
- Generalized periodic discharges 4
Neuroimaging
- Follow-up MRI to assess resolution of lesions 1
- Monitor for presence of hemorrhage on imaging, which is associated with poor outcomes 1
Prognosis Factors
- Poor outcome indicators:
- Altered sensorium
- Extensive cerebral edema
- Presence of hemorrhage on imaging
- Delayed control of causative factors 1
PRES is typically reversible with appropriate management within 2 weeks, though delayed diagnosis and treatment may lead to permanent neurological sequelae. Early diagnosis and aggressive management are crucial to prevent irreversible neurological damage 1.