EFFECT ON CARDIOVASCULAR FUNCTION AND IRON-METABOLISM OF THE ACUTE REMOVAL OF 2 UNITS OF RED-CELLS

Background: The collection from a donor of 2 red cell units at one tim e would decrease recipient exposure to viruses and alloantigens. If th e donor is a large person, the blood volume lost and the postdonation hemoglobin and/or hematocrit should be within acceptable limits. If th e donor is a large person, the blood volume lost and the postdonation hemoglobin and/or hematocrit should be within acceptable limits. The e ffect on cardiovascular function and iron metabolism requires descript ion. Study Design and Methods: Manual 2-unit erythropheresis was perfo rmed on eight donors, with the plasma returned. Donors had treadmill t esting of maximum aerobic power (VO(2)max) before donation, 24 hours a fter, and 8 to 11 weeks after. Serial samples were drawn for iron meta bolism studies. Results: Donors weighed 61.2 to 74.8 kg, and 9.6 to 11 .4 percent of their blood volume was removed. Mean VO2 max decreased f rom 84 percent of that predicted before donation to 74 percent 24 hour s afterward. By 8 to 11 weeks, hemoglobin returned to acceptable donor levels and mean VO2 max was 92 percent of that predicted. Mean hemogl obin fell from 14.4 to 11.7 g per dL (144 to 117 g/L) and rose to 13.9 g per dL (139 g/L) at 16 weeks. At 16 weeks, serum iron (120 +/- 47 v s. 83 +/- 33 mu g/dL [21 +/- 8 vs. 15 +/- 6 mu mol/L]), ferritin (40 /- 24 vs. 18 +/- 10 ng/mL [40 +/- 20 vs. 20 +/- 10 mu g/L]), and free erythroprotoporphyrin (19 +/- 5 vs. 28 +/- 5 mu g/dL [0.34 +/- 0.09 vs . 0.50 +/- 0.09 mu mol/L]) differed significantly from baseline levels . No major donor symptoms occurred. Conclusion: Two-unit erythropheres is was done with blood volume loss and postdonation hemoglobin no wors e than those that would occur in a 50-kg donor donating 450 mL. Cardio vascular effects and donor symptoms were mild. Two-unit red cell donat ions would be clinically advantageous, and they warrant further studie s of both utility and donor safety.