Unique risks of red blood cell transfusions in very-low-birth-weight neonates: associations between early transfusion and intraventricular hemorrhage and between late transfusion and necrotizing enterocolitis.

Red blood cell transfusions can be life-saving for neonates with severe anemia or active hemorrhage. However, risks of transfusions exist and should always be weighed against potential benefits. At least two transfusion risks are unique to very low birth weight neonates. The first is an association between transfusions given in the first days after birth and the subsequent occurrence of a grade 3 or 4 intraventricular hemorrhage. The second is an association between "late" RBC transfusions and the subsequent occurrence of necrotizing enterocolitis. Much remains to be discovered about the pathogenesis of these two outcomes. Moreover, work is needed to clearly establish whether transfusions are causatively-associated with these outcomes or are co-variables. This review will provide basic data establishing these associations and propose mechanistic explanations.