Ventriculoperitoneal Shunt Alone Does Not Guarantee Spinal Cord Protection After Complex Aortic Aneurysm Repair

Introduction: Spinal cord ischaemia (SCI) is a devastating complication of the treatment of thoraco-abdominal aneurysms. Peri-operative cerebrospinal fluid (CSF) drainage, typically using a spinal catheter, is a possible preventive measure. There are no reports or guidelines on peri-operative CSF drainage for this indication in patients with a ventriculoperitoneal (VP) shunt. Report: A single case of a patient suffering SCI after fenestrated endovascular aortic repair for the treatment of a pararenal aneurysm after previous open repair of an infrarenal aortic aneurysm is presented. Despite the presence of a patent VP shunt, elevated CSF pressures were observed after placement of a CSF drain. Discussion: A VP shunt with a gravitational component may drain insufficiently in bedridden patients who often lie with their head tilted on a cushion. In this position, both the differential pressure component and the gravitational component become active, thereby increasing the overall resistance to CSF outflow, hence increasing intracranial and intraspinal pressure. VP shunts with gravitational components should be managed with caution in the setting of prophylactic or therapeutic drainage of CSF to prevent SCI in extensive aortic repair. For reliable CSF pressure monitoring or active drainage in case of symptoms, the insertion of a spinal drain is indicated.