THE ESTIMATION OF EFFICACY OF ORAL IRON SUPPLEMENTATION DURING TREATMENT WITH EPOETIN-BETA (RECOMBINANT-HUMAN-ERYTHROPOIETIN) IN PATIENTS UNDERGOING CARDIAC-SURGERY

We estimated the efficacy of oral iron therapy during treatment with r hEPO in patients undergoing cardiac surgery who were contraindicated f or autologous blood donation. Seventy-six patients were enrolled in th is double-blind, placebo-controlled trial and assigned to the 2 treatm ent groups (5x500 U/kg body weight rhEPO or placebo intravenously over 14 d before surgery). During the treatment period all patients receiv ed 300 mg Fe2+ (iron glycine sulfate) orally per day, rhEPO therapy pr oduced significant increases in hemoglobin concentration (Hb), reticul ocyte count, hematocrit (Hct) and the hypochromic red blood cells (KRB C), and a decrease in transferrin saturation (41%) compared to the pla cebo group before surgery. However, the preoperative increase in HRBC was independent of the baseline ferritin and even correlated positivel y with the preoperative increase in Hct (r=0.47, p<0.01). In rhEPO pat ients there were inverse correlations between baseline serum iron and the preoperative increases in Hb (r=-0.39, p<0.05), Hct (r=-0.50, p<0. 01) and HRBC (r=-0.53, p<0.001). With this treatment regimen the KRBC appear to reflect the degree of erythropoietic stimulation rather than functional iron deficiency. The preoperative increases in reticulocyt es, HRBC and Hb/Hct in patients with ferritin <100 mg/l or transferrin saturation <16% showed no significant difference compared to their co mplementary groups. The preoperative decrease in storage iron and the inverse correlation between the baseline ferritin and the preoperative change in ferritin (r=-0.94, p<0.0001) in the rhEPO group indicate th at the iron requirement for hemoglobin synthesis is probably covered b y the breakdown of stored iron and an increase in the rate of absorpti on of orally administered Fe2+ Intravenous rhEPO treatment with 5x500 U/kg body weight in combination with 300 mg oral Fe2+/d given over 14 d before surgery is a suitable regimen to increase Hb by about 1.61 g/ dl and Hct by 0.06.