What is the immediate management for a patient presenting with Posterior Reversible Encephalopathy Syndrome (PRES)?

Immediate Management of Posterior Reversible Encephalopathy Syndrome (PRES)

The immediate management of PRES requires prompt identification and removal of triggering factors, discontinuation of offending medications, and very stringent blood pressure control to prevent permanent neurological damage. 1

Initial Assessment and Stabilization

• Identify and address triggering factors:

  • Severe hypertension (most common cause)
  • Immunosuppressive medications
  • Chemotherapy agents
  • Autoimmune disorders
  • Renal impairment
  • Pre-eclampsia/eclampsia 1

• Discontinue offending medications immediately:

  • Immunosuppressants
  • Chemotherapy agents
  • Other medications associated with PRES (e.g., ondansetron in high doses) 1, 2

Blood Pressure Management

• Implement stringent blood pressure control:

  • Target gradual reduction to avoid cerebral hypoperfusion
  • For severe hypertension (systolic BP ≥220 mmHg), use IV antihypertensives 1

• Preferred medications:

  • First-line: IV labetalol
  • Oral option: Nifedipine
  • Second-line: IV hydralazine 1

Seizure Management

• For active seizures:
  • Administer benzodiazepines for acute seizure control
  • Consider prophylactic anticonvulsants in high-risk patients 1

Management of 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 for maintenance
    • OR
    • Hypertonic 3% saline: 5 ml/kg IV over 15 minutes initially, 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

Surgical Intervention

• Consider surgical decompression in cases of refractory intracranial hypertension or malignant cerebral edema causing significant mass effect 3, 4

• Ventriculostomy may be necessary for hydrocephalus management 4

Specific Scenarios

• For eclampsia-related PRES:

  • Immediate delivery is essential to remove the triggering factor 1

• For medication-induced PRES:

  • Discontinue the offending agent immediately
  • Monitor for improvement after removal 1, 2

Monitoring and Follow-up

• Perform regular neurological assessments to detect early signs of deterioration 1, 5

• Monitor for complications:

  • Hemorrhagic transformation
  • Refractory intracranial hypertension
  • Permanent neurological deficits 3, 2

• Repeat neuroimaging to assess response to treatment 1

Prognostic Factors

• Poor outcomes are associated with:

  • Altered sensorium
  • Extensive cerebral edema
  • Presence of hemorrhage on imaging
  • Delayed control of causative factors 1

• Early diagnosis and treatment are crucial, as PRES is typically reversible within 2 weeks with appropriate management 1, 6

Pitfalls and Caveats

• Delayed diagnosis and treatment may lead to permanent neurological sequelae or death 1, 5

• Overly aggressive blood pressure reduction can cause cerebral hypoperfusion; aim for gradual reduction 1

• PRES can present atypically with involvement of anterior circulation or brainstem, requiring more aggressive management 3, 4

• Regular monitoring of patients on immunosuppressive therapy is important for early detection 1