One discussion this week included transperitoneal vs retroperitoneal  approach following AAA repair.

Reference: Buck DB, et al. Transperitoneal vs retroperitoneal approach for open abdominal aortic aneurysm repair in the targeted vascular NSQIP. Journal of Vascular Surgery. 2016 Sept;64(3):585-591. doi:10/1016/j.jvs.2016.01.055.

Summary: This study aims to identify the demographic and anatomical differences between patients currently selected for elective transperitoneal versus retroperitoneal AAA repair and to assess differences in intra-operative details, and perioperative mortality and complications.

Methods—All patients undergoing elective transperitoneal or retroperitoneal surgical repair for AAA between January 2011 and December 2013 were identified in the Targeted Vascular NSQIP database. Emergent cases were excluded. Baseline characteristics, anatomical detail, intraoperative and post-operative outcomes were evaluated among those with infrarenal or juxtarenal AAA only.

Results—1,135 patients were identified; 788 transperitoneal (69%), 347 retroperitoneal (31%).

• Evaluating infrarenal and juxtarenal aneurysms only, the retroperitoneal patients were less likely to have an infrarenal clamp location (43% vs. 68%), had more renal revascularizations (15% vs. 6%, p<.001), more visceral revascularizations (5.6% vs. 2.4%, p=0.014) and more lower extremity revascularizations (11% vs. 7%, p=0.021) compared to the transperitoneal approach. Postoperatively there were no differences in mortality, or return to OR.
• Transperitoneal patients had a higher rate of wound dehiscence (2.4% vs. 0.4%, p=0.045), while retroperitoneal patients had higher incidence of pneumonia (9% vs 5%, p=0.034), transfusions (77% vs. 71%, p=0.037), reintubations (11% vs. 7%, p=0.034) and a longer LOS (median 8 vs. 7 days, p=0.048).
• After exclusion of all concomitant procedures, only transfusions remained more common in the retroperitoneal approach (78% vs. 70%, p=0.036).
• Multivariable analyses showed only higher rates of reintubation in the retroperitoneal group (OR1.7, 95% CI 1.0-3.0, p=0.047).

Conclusions—The study found that, as the authors expected, the retroperitoneal approach was more commonly utilized for aneurysms with more proximal extent and was associated with higher rates of concomitant procedures as well as pneumonia, reintubations, transfusions and greater length of stay. The transperitoneal approach, however, had a higher rate of wound dehiscence. After multivariable analysis, however, most of these differences were simply related to concomitant procedures.

Further long-term data regarding late survival, bowel obstruction, and hernia formation will be useful to guide treatment selection. For the time being, the choice should be driven by anatomy and surgeon preference.