How do I treat Posterior Reversible Encephalopathy Syndrome (PRES) and diffuse vasogenic edema?

From the Guidelines

To treat Posterior Reversible Encephalopathy Syndrome (PRES) and diffuse vasogenic edema, the primary approach is to identify and remove the underlying cause while providing supportive care, with a focus on controlling blood pressure and managing seizures. The management of PRES and diffuse vasogenic edema involves a multifaceted approach, including:

• Aggressive control of blood pressure using IV medications like nicardipine (5-15 mg/hr), labetalol (2-8 mg/min), or clevidipine (1-21 mg/hr), aiming for a gradual 20-25% reduction in the first hours to avoid cerebral hypoperfusion 1
• Administration of benzodiazepines acutely (lorazepam 2-4 mg IV) followed by levetiracetam (500-1000 mg IV twice daily) or phenytoin (loading dose 15-20 mg/kg IV, then 300 mg daily) for seizure management 1
• Discontinuation or reduction of offending medications, particularly immunosuppressants, chemotherapy, or other neurotoxic agents
• Maintenance of euvolemia and avoidance of hyponatremia correction faster than 8 mEq/L/day if present
• Consideration of mannitol (0.25-1 g/kg IV) or hypertonic saline (3% NaCl, 30-60 mL bolus) for severe cases with increased intracranial pressure 1 The pathophysiology of PRES involves endothelial dysfunction leading to blood-brain barrier disruption, which explains why removing the trigger and controlling blood pressure are the cornerstones of treatment. Most patients improve within days to weeks with proper management, as PRES is typically reversible when the underlying cause is addressed promptly. It is essential to note that the management of cerebral edema in the context of ischemic stroke, as discussed in the guidelines from the American Heart Association/American Stroke Association 1, may differ from the management of PRES and diffuse vasogenic edema. However, the principles of controlling blood pressure, managing seizures, and providing supportive care remain crucial in both scenarios.

From the Research

Treatment of PRES and Diffuse Vasogenic Edema

• The treatment of Posterior Reversible Encephalopathy Syndrome (PRES) and diffuse vasogenic edema involves managing blood pressure and reducing cerebral edema.
• According to a study published in 2017 2, corticosteroid therapy is not associated with the severity of vasogenic edema in PRES.
• In terms of blood pressure management, a systematic review published in 2012 3 found that nicardipine and labetalol have comparable efficacy and safety in treating hypertensive crises.
• Another study published in 2021 4 compared the use of labetalol and nicardipine in controlling blood pressure in acute stroke patients and found that both medications are effective, but labetalol may have a shorter time to goal blood pressure.
• The management of hypertension in acute ischemic stroke is a controversial topic, and a study published in 2007 5 suggests that permissive hypertension may be the best approach, with antihypertensive treatment only warranted in patients with systolic blood pressure greater than 220 mm Hg or with concomitant medical issues.
• Guidelines for the acute treatment of cerebral edema in neurocritical care patients, published in 2020 6, recommend the use of hyperosmolar agents, such as mannitol or hypertonic saline, and corticosteroids in selected cases, with close monitoring for adverse effects.

Blood Pressure Management

• The goal of blood pressure management in PRES and diffuse vasogenic edema is to reduce blood pressure while avoiding hypotension and maintaining cerebral perfusion.
• Nicardipine and labetalol are commonly used medications for blood pressure management in this setting, with the choice of medication depending on the individual patient's needs and medical history.
• The use of predictable and titratable medications, such as nicardipine and labetalol, is recommended to judiciously reduce blood pressure and avoid sudden drops in blood pressure.

Cerebral Edema Management

• The management of cerebral edema in PRES and diffuse vasogenic edema involves the use of hyperosmolar agents, such as mannitol or hypertonic saline, to reduce intracranial pressure and cerebral edema.
• Corticosteroids may be used in selected cases, such as in patients with bacterial meningitis, but their use is not recommended in patients with intracerebral hemorrhage.
• Close monitoring for adverse effects, such as hypotension and electrolyte imbalances, is necessary when using these medications.