Extent II Thoracoabdominal Aortic Aneurysm Repair: How I Do It

Abstract

The primary risks associated with thoracoabdominal aortic aneurysm (TAAA) repair-namely operative death, paraplegia, and renal failure necessitating dialysis-are commonly related to the distal ischemia that occurs during aortic clamping and the disruption of vital branching arteries. Our technique for open TAAA repair has evolved over the course of 3 decades, from the unheparinized, simple "clamp-and-sew" approach learned directly from E. Stanley Crawford himself to a contemporary, multimodal strategy that uses an array of surgical adjuncts. Today, our approach to TAAA repair is largely standardized and based on the Crawford extents of TAAA repair, but we have maintained flexibility to explore new techniques and to adapt to the specific needs of patients. To protect the spinal cord, we routinely use mild passive hypothermia, cerebrospinal fluid drainage, left heart bypass, and reimplantation of crucial intercostal or lumbar arteries. The renal arteries are perfused with cold solution to protect the kidneys from ischemic damage, and the celiac axis and superior mesenteric artery are perfused with isothermic blood from the left heart bypass circuit, which minimizes the duration of abdominal-organ ischemia. The most extensive repair, Crawford extent II repair, typically replaces the aorta from just beyond the left subclavian artery to the aortic bifurcation; unsurprisingly, it commonly poses greater operative risk than do less extensive TAAA repairs (extent I, III, and IV). Subsequently, most surgical adjuncts used today were developed to ameliorate risk in extent II repair. Here, we provide a detailed description of our approach to open extent II TAAA repair.

Keywords: Crawford classifications; aortic aneurysm; neuroprotection; surgery; thoracoabdominal.