Strict Control of Blood Glucose With an Intravenous Insulin Infusion Decreases the Risk of Post-operative Lower Extremity Weakness After Complex Endovascular Aortic Aneurysm Repair

Abstract

It has previously been shown that post-operative lower extremity weakness (LEW) is associated with elevated blood and cerebrospinal fluid (CSF) glucose levels after branched endovascular aneurysms repair (BEVAR) of extensive aortic aneurysms. The purpose of this study was to determine whether a post-operative insulin infusion protocol (IIP) to achieve tight blood glucose control decreases the rate of LEW. From October 2013, blood and CSF samples were collected pre-operatively, immediately post-operatively, and on post-operative day one in asymptomatic patients undergoing BEVAR. In July 2016, an IIP was initiated to maintain post-operative blood glucose levels <120mg/dL for 48h. Data on demographics, operative repair, complications, and outcomes were collected prospectively. Between October 2013 and April 2018, 43 patients underwent BEVAR. Twenty-two (group A) underwent BEVAR before initiation of the IIP. Of these, seven (32%) developed LEW within 48h of repair. This was temporary in five (23%) and permanent in two (9%) patients. Post-operative blood glucose levels were significantly higher in patients with LEW compared with those without LEW (140±27mg/dL vs. 117±16mg/dL; p=.02). Post-operative CSF glucose levels were significantly higher in patients with LEW compared with those without LEW (102±15mg/dL vs. 77±15mg/dL; p=.001). The subsequent 21 patients (group B) underwent BEVAR after initiation of the IIP. No patient in group B developed LEW while on the IIP, but one (5%) developed paraplegia on post-operative day four. The rate of early LEW (<48h post-operatively) was significantly lower after initiation of the IIP (32% in group A vs. 0% in group B; p=.009). There was no difference in demographics, comorbidities, or operative time between the groups. An IIP to control blood glucose after BEVAR is associated with a decreased rate of post-operative LEW. Tight control of blood glucose should be considered after any extensive aortic reconstruction to minimise the risk of post-operative LEW.