Blood volume expansion with hyperoncotic colloids deteriorates allograft function in a canine model of renal...

We investigated the effects of acute maximal hydratation with hemoce (H) and dextran-40 (D40) on the postoperative graft function, following renal transplantation (RT) in a canine model.

After induction of anesthesia with pentobarbital (5 mg/kg), 18 beagle dogs were randomized to receive either saline solution to increase the central venous pressure (CVP) to 5 mm Hg (GI); H solution to increase the CVP to 10 mm Hg (GII); or D40 to achieve 15 mm Hg (GIII), before reperfusion. A pulmonary artery catheter was used to measure CVP, mean pulmonary artery pressure, and cardiac output (CO). The surgical procedure consisted of autotransplantation of the dog's left kidney an hour prior to cold ischemia with University of Wisconsin solution, followed by contralateral nephrectomy. Diuresis, creatinine (Cr), and BUN levels were measure at 24 hours before RT, as well as 24, 48, and 72 hours after the procedure.

Only in the treated groups did cardiac filling pressures and CO increase as a result of hydration. Only in the GI group did serum Cr and blood urea nitrogen significantly peak at the second postoperative day while it continued to increase at two (GII) and three (GIII) times greater than GI on the third day. Histological examination showed osmotic nephrosis like-lesions only among treated grafts.

We concluded that maximal hydration with H and D40 colloid deteriorated postoperative graft function after RT. We believe that in the future the effects of any colloid solution should be tested in an animal model in the fashion as we have described, in order to know which one, and at what dose, is the safest to improve kidney allograft outcome.