Posterior reversible encephalopathy syndrome (PRES) in critically ill obstetric patients

Objective: To describe clinical, neuroradiological and evolutionary findings in obstetric patients with posterior reversible encephalopathy syndrome (PRES). Design: Retrospective case series. Setting: University intensive care unit (ICU). Patients: Four critically ill patients. Two patients experienced PRES in late postpartum without the classical pre-eclamptic signs. All patients showed impairment of consciousness and epileptic seizures; two of them presented cortical blindness and headache, too. True status epilepticus (SE) occurred in two cases. In all patients MRI showed the typical feature of gray-white matter edema, mainly localized to the temporo-parieto-occipital areas. Interventions: Normalization of high blood pressure (BP) and treatment of seizures. Two patients with SE and severe impairment of consciousness were treated with an intravenous valproate (ivVPA) bolus followed by continuous infusion. Measurements and results: In three cases, neurological and MRI abnormalities completely resolved in about a week. Another patient died due to subarachnoid hemorrhage. Conclusion: Posterior reversible encephalopathy syndrome is a well described clinical and neuroradiological syndrome characterized by headache, altered mental status, cortical blindness and seizures, and a diagnostic MRI picture; usually reversible, PRES can sometimes result in death or in irreversible neurological deficits, thus requiring early diagnosis and prompt treatment. PRES can have various etiologies, but pregnancy and postpartum more frequently lead to this condition. Treatment of seizures deserves special attention since the anti-epileptic drugs currently used in SE management may worsen vigilance as well as autonomic functions. Extensive research is needed to assess the role of ivVPA in this condition.