What are the risk factors for renal failure following open elective abdominal aortic aneurysm repair?

Objectives: Renal failure following abdominal aortic aneurysm (AAA) repair is a common and significant complication. The objective of this study was to identify risk factors for renal failure following open elective AAA repair.

Design: A retrospective analysis of prospectively collected multi-centre data.

Materials: Consecutive data on patients undergoing open elective AAA repair were collected between January 2000 and December 2010. Patients with pre-operative serum creatinine >200 μmol/L were excluded.

Methods: Renal failure was reported by clinicians and included all patients requiring post-operative renal-replacement therapy. Univariate and multivariate analyses were used to identify renal failure risk factors. A simplified clinical risk score was developed.

Results: Post-operative renal failure occurred in 140 (6.0%) of 2347 patients and was associated with age >75 (OR = 1.58, 95%CI 1.11-2.26), symptomatic AAA (OR = 1.77, 95%CI 1.24-2.52), supra/juxta renal AAA (OR = 2.17, 95%CI 1.32-3.57) pre-operative serum creatinine >150 (OR = 2.75, 95%CI 1.69-4.50), treated hypertension (OR = 1.87, 95%CI 1.28-2.74), and respiratory disease (OR = 2.08, 95%CI 1.45-2.97). Patients with post-operative renal failure had significantly higher 30-day mortality (35.0% vs. 4.3%, p < 0.001).

Conclusions: Renal failure following open elective AAA repair was associated with an increased risk of mortality. Risk factors for post-operative renal failure were identified and a simple clinical risk score developed to facilitate focussed care strategies for high-risk patients.