Written by: Jilan Shimberg, MD (NUEM ‘26) Edited by: Michael Tandlich, MD (NUEM ‘24)
Expert Commentary by: Matthew B Maas, MD MS
Expert Commentary
Posterior Reversible Encephalopathy Syndrome (PRES) is a potentially catastrophic but frequently overlooked diagnosis. It often coexists in a pathophysiological spectrum with Reversible Cerebral Vasoconstriction Syndrome (RCVS). PRES is the result of autoregulatory failure that permits excessive cerebral blood flow which damages affected regions of brain tissue. The role of hypertension is relative: PRES can develop from absolute hypertensive emergency or from more modest, relative increases in blood pressure (BP) in the context of factors that disrupt normal autoregulatory physiology. PRES can rarely be visualized by head CT although comorbid RCVS can often be identified by CT-angiography. T2-weighted MRI (e.g., FLAIR) is the ideal imaging modality for diagnosis.
PRES can quickly devolve from a throbbing, atypical headache to seizures and brain hemorrhage, so intervening as soon as possible with aggressive BP reduction is the goal. Nicardipine infusion for strict BP management and admission to a unit capable of neurologic monitoring is ideal. Adjunctive magnesium infusions are indicated for pregnant and postpartum cases. Seizure management follows generally conventional practices. A key principle is to consider BP optimization for possible PRES in any patient suspected of it, even before confirmatory advanced imaging is obtained. Any important contraindication to acute BP lowering can be identified by a noncontrast head CT and CT-angiogram of the head and neck, enabling such a strategy to be deployed safely in the ED.
Matthew B Maas, MD, MS
Vice Chair for Clinical Affairs (interim),
Chief, Division of Hospital Neurology,
Co-Director, Data Science Concentration, Master of Public Health Program,
Associate Professor of Neurology and Anesthesiology,
Northwestern University Feinberg School of Medicine
Director, Regional Inpatient Neurology,
Northwestern Medicine
Medical Director, Inpatient Neurosciences,
Medical Director, Clinical Documentation,
Northwestern Memorial Hospital
How To Cite This Post:
[Peer-Reviewed, Web Publication] Shimberg, J. Tandlich, M. (2024, Jul 22).Posterior Reversible Encephalopathy Syndrome (PRES) [NUEM Blog. Expert Commentary by Maas, MB]. Retrieved from http://www.nuemblog.com/blog/PRES
