The Effects of Intraoperative Fenoldopam on Renal Blood Flow and Tubular Function following Suprarenal Aortic Cross-clamping

This study evaluated the effect of fenoldopam, a selective dopamine (DA1) agonist, on renal blood flow and renal tubular function following renal ischemia induced by suprarenal aortic cross-clamping. Twenty anesthetized research pigs received either fenoldopam (10 µg/kg/min; n = 10) or saline (n = 10) beginning 20 min before suprarenal aortic cross-clamping and continuing for 20 min after clamp release, for a total infusion time of 160 min (120-min cross-clamp). Recordings of renal blood flow, mean arterial pressure, and heart rate were taken at baseline, during cross-clamping, and immediately postclamp. Ischemic renal injury was evaluated by serum creatinine and by histologic grading of acute tubular necrosis. Treatment with fenoldopam increased renal blood flow in comparison to that in the control group (p = 0.03). The mean creatinine increase from baseline at 6 hr and 18 hr after cross-clamp removal for the fenoldopam-treated group was significantly less than that in the control group (p < 0.001). On histologic evaluation, the mean score for the degree of tubular necrosis was significantly higher in the control group (p = 0.02), indicating less derangement of tubular morphology in the fenoldopam group. This study demonstrated that the intraoperative use of a continuous infusion of fenoldopam during suprarenal aortic cross-clamping results in increased renal blood flow, less postoperative rise in creatinine, and better preservation of tubular histology in the pig model.