Effects of fenoldopam on renal blood flow and its function in a canine model of rhabdomyolysis.

Our hypothesis was that fenoldopam, a selective DA1 agonist, would protect against rhabdomyolysis-induced renal injury.

We studied the effects of intravenous fenoldopam (0.1-1.0 microg kg(-1) min(-1)) or saline on renal blood flow and function in 10 anaesthetized Labrador dogs in whom rhabdomyolysis and myoglobinuric acute renal failure had been induced by administration of glycerol 50% (10mL kg(-1)) intramuscularly. Haemodynamic measurements including renal blood flow and derived parameters of renal function including creatinine clearance were recorded before and for the 30 min following glycerol injection, and during the 3 h following commencement of each infusion. Serum malondialdehyde concentrations were measured before and 15 min after glycerol intramuscularly, and 30 and 150 min after commencement of the infusion.

In the fenoldopam group, creatinine clearance was less than placebo at 1 and 2 h after commencing the infusion (12.7 +/- 11.5 versus 31.3 +/- 9.9 mL min(-1), P = 0.04; 8.5 +/- 5.3 versus 20.1 +/- 7.4 mL min(-1), P = 0.03). A 140-fold increase in serum malondialdehyde concentration occurred in one dog (fenoldopam group).

Fenoldopam increased the severity of the renal injury in this canine model of myoglobinuric acute renal failure.