Development of a novel split, frozen, thawed and washed red cell component for intrauterine transfusion

Background and Objectives Provision of red cells for intrauterine transfusion (IUT) can be challenging when the mother has an antibody to a high frequency antigen, as compatible allogeneic red cells may be scarce. The aim was to validate a novel component: split, frozen, thawed, washed and irradiated red cells for IUT, which could be used if foetal transfusion with maternal blood is necessary. Materials and Methods Six standard red cell concentrates were glycerolized on Day 5 and split into three smaller packs before freezing. A split from each donation was thawed and deglycerolized using the ACP215 and resuspended in saline‐adenine‐glucose‐mannitol. The haematocrit was adjusted to IUT (70%–85%). The components, each approximately 80 mL, were immediately irradiated and tested for full blood count, haemolysis and supernatant potassium 8 and 24 h later. Results At 8 and 24 h post manufacture, haemolysis was 0.20% (0.16%–0.25%) and 0.24% (0.18%–0.29%), respectively, and supernatant potassium was 20.3 mmol/L (15.1–27.1 mmol/L) and 43.1 mmol/L (33.5–58.4 mmol/L), respectively (mean [range]). Both haemolysis and potassium were within levels for standard irradiated IUT units. Conclusion Red cells split, frozen, thawed, washed and manufactured into IUT units and immediately irradiated are expected to be a beneficial component for very rare clinical cases.