Abstract 124

Aims: 1. To estimate RCV in transfused PTI, based on dilution principle; flowcytometric quantitation of red cell antigen % falls in the recipient's circulation after a known amount of donor antigens transfused: yields RCV. BV = RCV/Hct. 2. To seek “real-time”" RCV estimation during transfusion, to allow full correction of blood volume depletion during a single transfusion. Patients:20 neonates, of gestation 26-40, median 27 weeks, received 21 transfusions aged 1-46, median 2 days.

Results: In 20 of 21 red cell transfusions, "mis-matches" allowed RCV and BV estimation using donor/recipient distinction by these antigens: RhD: 16; MN: 11; Fya: 11; Fyb: 8; Jka: 3, Jkb 3/21. Hcts ranged from 0.34-0.49, median 0.24 and RCVs from 14-42, median 25 ml/kg, pre-transfusion.(Normal RCV c.35-55 ml/kg). Correlation Coefficient, Hct RCV = 0.245.

Conclusions: Using these methods, pre-transfusion RCV and BV can be estimated in most “transfusion episodes” in preterm infants, using technology available in most hospitals with SCBU and NICU. Multiple packs of donor red cells can permit normalization of circulating RCV and BV, with minimal “donor-exposures”, so as to optimize the blood for oxygen transport and organ perfusion in critical care neonatology.