Delayed Emergence From Anesthesia Due to Posterior Reversible Encephalopathy Syndrome (PRES): A Case Report

Posterior reversible encephalopathy syndrome (PRES) is a rare clinical and radiological syndrome that presents as rapid onset of neurological symptoms such as headache, visual loss, impaired mental status, and seizure activity associated with characteristic focal white matter vasogenic edema. When promptly recognized and managed, these changes are usually reversible. PRES is most commonly associated with hypertensive crises, renal insufficiency, and the use of immunosuppressive therapies, though it may arise in various clinical contexts. Despite its significance, reports of PRES in the field of anesthesiology remain limited. This case report presents the case of a 46-year-old male admitted for elective ambulatory ophthalmic surgery under general anesthesia who developed delayed emergence from anesthesia and post-operative blindness, both attributed to the intraoperative onset of PRES. Anesthesiologists should be vigilant for PRES as a potential complication during the perioperative period, and consider it in the differential diagnosis for delayed emergence from anesthesia. Clinical suspicion should warrant prompt imagiological confirmation by magnetic resonance imaging (MRI), as delayed recognition and management can result in severe and long-term neurological disability.