Posterior Reversible Encephalopathy Syndrome After Thoraco-Abdominal Aortic Replacement

INTRODUCTION: Induced hypertension, administered peri-operatively during thoraco-abdominal aortic intervention, is one of the most effective methods to maintain spinal cord perfusion pressure. Posterior reversible encephalopathy syndrome or reversible cerebral vasoconstriction syndrome is a rare encephalopathy, possibly caused by excessive hypertension, usually encountered in the obstetric or cerebrovascular department. REPORT: A 61 year old man underwent open surgery for repair of an extent II dissecting thoraco-abdominal aneurysm. Several attempts at spinal drainage tube insertion one day prior to surgery failed. The Adamkiewicz artery was anastomosed by bypass, and transcranial motor evoked potentials were generally stable. Initially, no apparent neurological abnormality was observed after surgery; however, paraplegia occurred on post-operative day 1. The patient’s mean arterial pressure increased from > 85 mmHg to > 95 mmHg. His systolic blood pressure occasionally exceeded 170 mmHg. On post-operative day 3 he became blind. A serial imaging test revealed cerebral oedema of both posterior lobes and segmental constriction of the vertebral and basilar arteries. Posterior reversible encephalopathy syndrome with reversible cerebral vasoconstriction syndrome was diagnosed from the clinical context and imaging tests. Despite treatment with magnesium and calcium channel blockers, the patient’s visual acuity remained poor. DISCUSSION: Excessive induced hypertension for spinal cord protection could rarely lead to cerebral vascular dysfunction, resulting in irreversible neurological damage. Awareness of this rare but devastating complication may help in early diagnosis, potentially mitigating permanent sequelae.