Clinical approach for thoracoabdominal aortic aneurysm repair

Abstract

Thoracoabdominal aortic aneurysm repair represents a continuing challenge for the vascular surgeon. Although myocardial dysfunction and renal failure used to be worrisome problems after this procedure, adequate diagnostic evaluation and simple intraoperative maneuvers have dramatically reduced both potential complications. However, paraplegia, intraoperative coagulopathy, and respiratory failure remain continuing problems.

Our approach represents a multimodality attempt to minimize the risks of this procedure. Preoperative evaluation includes functional cardiac testing and duplex carotid screening. Major occlusive lesions in either of these regions are corrected prior to thoracoabdominal aneurysm repair. Patients with renal dysfunction are not excluded from thoracoabdominal aneurysm repair; however, preoperative hydration is used and we routinely provide for a delay between preoperative angiography and surgical repair, thus minimizing the potential nephrotoxic effect of the angiogram contrast load. At the time of operation, an intrathecal catheter is inserted for monitoring cerebral spinal fluid (CSF) pressure and for drainage in order to keep the CSF pressure below 10 mmHg. CSF drainage is also continued for 3 days postoperatively. A shunt or bypass is generally used for patients with type I to type II thoracoabdominal aneurysm. An inlay technique is used for graft replacement of the aneurysm and as many intercostal arteries as possible are routinely reimplanted. No attempt is made to monitor spinal cord function during repair. In order to minimize perioperative bleeding complications, visceral ischemia time is kept to a minimum. Pharmacologic manipulation and systemic or regional cooling is used to minimize the reperfusion injury. Using this multimodality approach, the overall incidence of neurologic deficit in over 200 thoracoabdominal aneurysm repairs is 4.4%. Intraoperative mortality is 2.5% and the incidence of reoperation for bleeding is 4.8%. Thoracoabdominal aneurysm repair can be done safely and with acceptable morbidity if appropriate attention is paid to preoperative evaluation, perioperative technique, and postoperative care.