A new preparation method for red blood cells for intrauterine transfusion enabling reduction of donor exposure.

BACKGROUND: Severe hemolytic anemia of the fetus, caused by maternal red blood cell (RBC) alloantibodies, is treated with intrauterine transfusion (IUT) of RBCs. Because IUT is associated with additional antibody formation, RBCs with the closest match between donor and mother are preferred. Because one fetus needs a median of three IUTs, finding such RBCs is complicated. Collection of repeated low-volume donations from one selected donor during the entire IUT treatment period would reduce donor exposure and possibly IUT-associated alloimmunization.

STUDY DESIGN AND METHODS: Whole blood (WB) donations of 100 and 200 mL were diluted with saline, filtered, centrifuged, and separated to prepare experimental RBCs. Before and after gamma irradiation, the RBCs were sampled for comparison of in vitro quality with standard RBCs for IUT. An additional washing procedure was investigated to remove anti-A/-B.

RESULTS: Experimental RBCs were leukoreduced to levels conforming with current guidelines and had final volumes of 44 (n = 12) and 84 (n = 8) mL with hematocrit levels between 0.80 and 0.88 L/L. Hemolysis was lower (0.12% vs. 0.42%), potassium leakage comparable, adenosine triphosphate levels lower (4.8 µmol/g Hb vs. 6.1 µmol/g Hb), and 2,3-diphosphoglycerate levels higher (10.3 µmol/g Hb vs 7.7 µmol/g Hb) at 6 hours after irradiation (product expiration time) compared to standard RBCs for IUT (n = 3). Anti-A/-B titers decreased substantially by the washing procedure.

CONCLUSION: RBCs for IUT can be prepared from 100- or 200-mL WB donations, showing the potential of this new blood product to reduce donor exposure. A washing procedure is recommended to remove anti-A/-B.