Retroperitoneal versus Transperitoneal Approach for Open Repair of Complex Abdominal Aortic Aneurysms

Several studies have demonstrated advantages of the retroperitoneal approach (RP) over the transperitoneal approach (TP) for infrarenal abdominal aortic aneurysm (AAA) repair. A retrospective analysis was performed comparing the outcomes of a TP vs. RP surgical approach for open complex AAA (cAAA) repair and evaluated their relative use over time.Patients undergoing open repair for intact cAAA (juxtarenal, suprarenal, or type IV thoraco-abdominal aortic aneurysms) between 2011 and 2019 were identified in the National Surgical Quality Improvement Program. The primary outcome was peri-operative death. Secondary outcomes included peri-operative complications and approach use over time. Multivariable adjustment was performed by creating propensity scores and using inverse probability weighted logistic regression.Among 1 195 patients identified, 729 (61%) underwent cAAA repair via a TP approach and 466 (39%) via an RP approach. Compared with a TP approach, RP patients more frequently had a supracoeliac clamp position (32% vs. 20%, p < .001) and concomitant renal revascularisation (30% vs. 18%, p < .001). After adjustment, an RP approach was associated with lower odds of peri-operative death (4.0% vs. 7.2%; odds ratio [OR] 0.54; 95% confidence interval [CI] 0.32 - 0.91; p = .022). Furthermore, an RP approach was associated with lower odds of any major complication (24% vs. 30%; OR 0.73; 95% CI 0.56 - 0.94), cardiac complications (4.9% vs. 8.2%; OR 0.60; 95% CI 0.37 - 0.96), wound complications (2.1% vs. 6.0%; OR 0.34; 95% CI 0.17 - 0.64), and post-operative sepsis (0.8% vs. 2.4%; OR 0.37; 95% CI 0.12 - 0.99). The proportion of repairs using an RP approach decreased between 2011 - 2015 and 2016 - 2019 (42% vs. 35%, p = .020), particularly for suprarenal and type IV thoraco-abdominal aneurysms (49% vs. 37%, p = .023).In open cAAA repair, the RP approach may be associated with lower peri-operative mortality and morbidity rates compared with the TP approach. However, it was found that the relative use of the RP approach is decreasing over time, even in suprarenal/type IV thoraco-abdominal aneurysms, and repairs using a supracoeliac clamp. Increased use of the RP approach, when appropriate, may lead to improved outcomes following open cAAA repair.