Reversal of acute renal failure using hemodilution with hydroxyethyl starch

Acute renal failure (ARF) was induced in two groups of unilaterally nephrectomized dogs by occluding the renal artery, vein, and ureter of the remaining kidney for 2 hours. The control group (Group I), had no therapy; in the experimental group (Group II), isovolemic hemodilution was carried out using 6% hydroxy ethyl starch (HES) as diluent. The hematocrit in the experimental animals was lowered from 41.62 +/- 3.6% to 23.75 +/- 5.2% after renal occlusion. The mean arterial pressure and the mean pulmonary arterial pressure were unchanged in either group. Cardiac output increased following hemodilution from 1.66 +/- 0.35 to 2.70 +/- 0.50 L/min while it remained unchanged in Group I. Control animals developed ARF characterized by progressive rise in serum creatinine concentration and death. Only 1/7 Group I animals was alive on day 7 compared to 7/7 of Group II (p less than 0.01). ARF that developed initially in Group II began to resolve after day 4. There was a progressive and significant fall in serum creatinine concentration from 6.48 +/- 0.67 mg/dl on day 4 to 4.08 +/- 0.83 mg/dl on day 7 (p less than 0.001). Immediate isovolemic hemodilution with HES can reverse ARF induced by ischemia.