Differences in renal response between endovascular and open repair of abdominal aortic aneurysms

Objectives: to determine the difference in renal and systemic response between open and endovascular aneurysm repair. Materials and Methods: we studied prospectively 22 patients undergoing open repair (OR) and 15 patients undergoing endovascular repair (ER). Blood and urine samples were taken preoperatively (TO) and before clamping of the aorta or femoral artery (T1) and 5 min (T2), 1 h (T3), 6 h (T4), 24 h (Day 1) and 48 h (Day 2) after declamping. Albumin/ creatinin ratio (AC ratio) in urine, serum albumin, serum creatinin, serum C-reactive protein and serum lactate were determined. Results: the urinary AC ratio in ER was significantly lower than in OR (p<0.001). In both groups the rise in urine albumin/creatinin ratio after declamping (T2, T3) was significant (p<0.001). C-reactive protein was raised significantly at day 1 and 2 in both groups (p<0.001) with no difference between the groups. Serum lactate values were significantly higher in OR. There was a significant increase in serum lactate 6 h after declamping in the ER group. Conclusions: after endovascular repair renal damage is less compared to open repair. There is a significant systemic reaction to the endovascular repair causing mild, short-lasting damage to the kidney. This systemic response is most probably induced by a combination of ischaemia reperfusion injury and the surgical trauma of the procedure. Other possible explanations are discussed.