Erythropoietin accelerates the recovery from extreme hemodilution: a randomized, placebo-controlled study in dogs.

Six splenectomized beagles of either sex (13.8 +/- 2.2 kg) were randomly treated either with 500 U/kg recombinant human erythropoietin (rhu-EPO) (verum group, n = 3) or an equivalent volume of the vehicle (placebo group, n = 3). Both solutions were given intravenously for 3 days. At day 4 after onset of treatment, the dogs were anesthetized and subjected to isovolemic hemodilution using 6% Dextran 60 (MW 60,000) down to a hematocrit of 0.10. During the recovery period vehicle or rhu-EPO was given every other day until the hematocrit reached control values. Every day venous blood samples were withdrawn, and the hematocrit as well as the concentrations of hemoglobin and 2,3-diphosphoglycerate were determined. In addition, the platelets and reticulocytes were counted. Treatment with rhu-EPO shortened the time of hematocrit recovery from 20 (placebo) to 11 days (p less than 0.05). The reticulocyte count peaked at day 2 (verum) versus day 5 (placebo). These findings indicate a successful stimulation of red blood cell production after extreme hemodilution in animals treated with erythropoietin. Therefore, rhu-EPO may allow to optimize blood donation programs as well as preoperative hemodilution and yield both, higher amounts of autologous blood and an accelerated reversal of dilutional anemia.