Mannitol and renal dysfunction after endovascular aortic aneurysm repair procedures: a randomized trial.

Objective: Endovascular aortic aneurysm repair (EVAR) may result in deterioration of renal function. Mannitol has renovascular and antioxidant properties that could prove beneficial in this respect.

Design: A randomized prospective study.

Setting: Attikon University Hospital, single institution.

Participants: Eighty-six patients undergoing elective EVAR under regional anesthesia.

Methods: Patients received hydration alone (controls) or hydration plus mannitol (0.5 g/kg).

Measurements And Main Results: Creatinine, serum cystatin-C, urine neutrophil-gelatinase-associated lipocalin (NGAL), albuminuria and serum urea were measured 24 hours and 72 hours after the procedure (baseline NGAL was measured in 19 randomly selected patients). Serum creatinine also was measured at the followup of the patients. Serum creatinine and cystatin-C were lower in the mannitol group at 24 hours postoperatively (creatinine, mannitol [n=43]; 1.07±0.26 [CI95%: 0.99-1.15] v controls [n=43]; 1.20±0.30 [CI95%: 1.11-1.30]), but not at 72 hours (creatinine, mannitol [n=43]; 1.13±0.29 [CI95%: 1.04-1.22] v controls [n=43]; 1.26±0.41 [CI95% 1.15-1.38]). Urine NGAL increased substantially at 24 hours without differences between groups. At followup (controls: 13±7 months; mannitol: 12±7 months), there were no differences between creatinine or creatinine clearance (creatinine: controls [n=28]; 1.15±0.39 [CI95% 1.02-1.29] v mannitol [n=23]; 1.05±0.27 [CI95%: 0.95-1.17]). The overall changes of creatinine and creatinine clearance with time were significant in controls but not in the mannitol group. The classification according to the RIFLE criteria yielded 4 patients at risk for renal injury and 2 with renal injury in the control group and 6 patients at risk with no patients with injury in the mannitol group, but the difference of renal dysfunction between the 2 groups was not statistically significant.

Conclusions: Mannitol plus hydration during EVAR provides a small but significant benefit for renal function. Future preventive protocols aiming at greater restoration of renal function after EVAR could include mannitol as a useful component.