A retroperitoneal operative approach is associated with improved perioperative outcomes compared with a transperitoneal approach in open repair of complex abdominal aortic aneurysms

Objective: Several studies have demonstrated the advantages of a retroperitoneal (RP) vs a transperitoneal (TP) approach during open repair of infrarenal abdominal aortic aneurysms (AAAs). We compared the outcomes after open repair of complex AAAs (cAAAs) using an RP vs a TP approach and evaluated the relative use of these approaches over time. Methods: We identified all patients who had undergone open intact cAAA repair in the Vascular Quality Initiative from 2003 to -2019 and created 1:1-propensity score-matched cohorts stratified by the operative approach (RP vs TP). The primary outcome was perioperative mortality. The secondary outcomes included perioperative complications and approach usage over time. To create 1:1 propensity score-matched cohorts, the patients were matched for demographics, comorbidities, and anatomic and/or intraoperative characteristics, including proximal clamp site and renal revascularization. The approach usage over time was determined by plotting the proportion of RP usage over time for the overall open cAAA cohort and subgroups of repairs using a supraceliac cross clamp, repair with concomitant renal revascularization, and repairs performed at high-volume centers (highest quintile, >11 cases annually). Results: Of a total of 4613 patients, 2843 (62%) had undergone open cAAA repair using the TP approach and 1770 (38%) using the RP approach. Of the 1256 matched pairs, the RP approach was associated with lower risk of perioperative mortality compared with the TP approach (3.9% vs 6.8%; relative risk [RR], 0.57; 95% confidence interval [CI], 0.41-0.80; P = .001). Furthermore, the RP approach was associated with a lower risk of cardiac complications (7.2% vs 9.6%; RR, 0.75; 95% CI, 0.58-0.98), bowel ischemia (3.1% vs 5.4%; RR, 0.56; 95% CI, 0.39-0.84), and postoperative dialysis (3.3% vs 5.5%; RR, 0.59; 95% CI, 0.41-0.87). Overall, the proportion of patients who had undergone repair via an RP approach became lower over time (−1.0%/y; 95% CI, −1.5 to −0.5; P < .001). A similar trend in the decrease was found for the patients who had undergone repair with a supraceliac clamp (−2.3%/y; 95% CI, −3.6 to −1.0; P < .001) and in the high-volume hospitals (−2.1%/y; 95% CI, −3.4 to −0.8; P = .001), although no statistically significant decrease in RP usage was found for the patients who had undergone concomitant renal revascularization (−0.9%/y; 95% CI, −2.6 to 0.8; P = .28). Conclusions: For open cAAA repair, an RP approach was associated with lower perioperative mortality and complications compared with a TP approach. However, the relative usage of the RP approach has been decreasing over time. An increased adoption of the RP approach, when appropriate, might lead to improved outcomes with open cAAA repair.