REDS Study Evaluates Blood Transfusion Factors in Very-Low-Birth-Weight Infants

Findings published in JAMA Network Open suggest that median pretransfusion hemoglobin level and anticoagulant preservative solution may be associated with serious morbidity and mortality among very-low-birthweight (VLBW) infants. Most other donor characteristics and blood banking practices were not associated with the study's primary composite outcome.

The Transfusion in Preterm Infants (TIPI) study, conducted through the National Heart, Lung, and Blood Institute's Recipient Epidemiology Donor Evaluation Study-IV-Pediatric (REDS-IV-P) Program, enrolled 2,605 VLBW infants born at eight U.S. hospitals between 2019 and 2023, including 1,283 who received RBC transfusions. Investigators linked donor, blood component and recipient data to evaluate associations with a composite outcome of severe intraventricular hemorrhage, necrotizing enterocolitis (NEC), late-onset sepsis, severe bronchopulmonary dysplasia (BPD), and retinopathy of prematurity or death.

After adjusting for illness severity and hospital differences, investigators found that infants who received RBC units stored in the additive solutions AS-1 or AS-5 had lower odds of the primary composite outcome than those receiving units stored in citrate phosphate dextrose adenine (CPDA-1) or citrate phosphate dextrose (CPD). Higher median pretransfusion hemoglobin levels were also associated with the primary outcome.

No significant associations were observed between the primary composite outcome and donor sex, donor age, donor hemoglobin, RBC storage duration, postirradiation storage duration, transfusion dose, donor exposure or washed RBCs.

The authors cautioned that the association between higher pretransfusion hemoglobin levels and the primary composite outcome may reflect greater illness severity and confounding by indication rather than a direct effect of higher transfusion thresholds. At the same time, they noted that approximately 25% of infants with the primary outcome received transfusions at hemoglobin levels above 11 g/dL, and that it remains possible that these higher transfusion thresholds may be associated with worse outcomes.

Additionally, the authors said anticoagulant preservative solution was of particular interest because its use varies among hospitals based on blood suppliers and institutional preferences. They concluded that it may represent a potentially modifiable transfusion variable for future study.