At some institutions all infants requiring RBC transfusions in neonatal intensive care units (NICUs) receive only group O RBCs. Although transfused group O plasma is minimized in packed RBCs, small amounts of residual anti-A, anti-B, and anti-A,B in group O packed RBCs may bind to the corresponding A and B antigens of non-group O RBCs, possibly hemolyzing their native RBCs and thereby releasing free hemoglobin, theoretically resulting in hypercoagulability and promoting bacterial growth from free iron.
Premature infants in the University of Kentucky Children's Hospital NICU database who were transfused (all received group O transfusions) were compared for a number of severity markers to determine if non-group O patients had worse outcomes than group O patients.
In this NICU sample, 724 neonates received at least 1 blood component. No significant differences were found between group O and non-group O infants with regard to final disposition or complications.
This reassuring finding validates the longstanding neonatal transfusion practice of using group O packed RBCs for infants of all blood groups in the NICU. However, a recent study shows increased mortality from necrotizing enterocolitis in group AB neonates at a facility transfusing only group O RBCs to neonates of all blood groups and suggests a change in neonatal transfusion practice to ABO group-specific RBCs; therefore more studies may be warranted.