Thirty-Day Outcomes of Open Abdominal Aortic Aneurysm Repair by Proximal Clamp Level in Patients with Normal and Impaired Renal Function

Abstract Objective Open surgical abdominal aortic aneurysm (AAA) repair (OSR) is often reserved in contemporary practice for complex aneurysms requiring supra-renal or supra-celiac proximal clamp level. This study investigates the associated 30-day outcomes of different proximal clamp levels in OSR of complex infra-renal/juxta-renal AAA in patients with normal renal function and those with chronic renal insufficiency (CRI). Methods All patients undergoing elective OSR of infra-renal and juxta-renal AAA were identified in the American College of Surgeons – National Surgical Quality Improvement Program (ACS-NSQIP) Targeted-AAA database from 2012-2018. Patients were stratified into two cohorts: normal renal function (eGFR≥60ml/min) and CRI (eGFR Results There were 1284 normal renal function and 524 CRI patients. Proximal clamp levels were: infra-renal (n=1080; 59.7%), inter-renal (n=337; 18.6%), supra-renal (n=279; 15.4%), and supra-celiac (n=112; 6.2%). In the normal renal function cohort, there was no difference in 30-day mortality with any clamp level. Increased 30-day acute renal failure was only observed with the supra-celiac versus infra-renal clamp level comparison (5.9% vs. 1.5%; aOR=3.97; 95% CI=1.04-5.18; P=.044). In the CRI cohort, supra-celiac clamping was associated with increased renal composite complications (22.7% vs. 5.6%; aOR=8.81; 95% CI=3.17-24.46; P Conclusions In elective OSR of infra-renal and juxta-renal AAA for CRI patients there is a heightened mortality risk with supra-celiac clamping, and increased renal morbidity with supra-renal clamping, which are not present in normal renal function patients. Every effort should be made to keep proximal clamp level as low as possible, particularly in CRI patients.