Freshly Irradiated RBCs Improve Intracerebral Oxygen Saturation in Newborns: JAMA
Preterm infants in neonatal intensive care units (NICUs), particularly those with extremely low birth weight (<1000 g), almost invariably require multiple transfusions of red blood cells (RBCs) before their estimated term birth date. Most blood transfusions are provided to medically stable infants with chronic anemia (anemia of prematurity), with the aim of increasing oxygen delivery to the metabolically active organs during the critical phase of growth and neurodevelopment.
A recent study suggests that on-demand RBC irradiation may be considered at institutions to optimize oxygen delivery for the transfusion recipient. The study findings were published in the JAMA Pediatrics on March 28, 2022.
Transfusion-associated graft-vs-host disease (TA-GVHD) is a rare but life-threatening complication of RBC transfusion that affects individuals with established immunodeficiency. It remains uncertain whether modern prestorage leukoreduction alone is sufficient in preventing TA-GVHD. Also, unknown whether freshly irradiated RBCs are more efficacious than irradiated and stored RBCs in preterm infants with high transfusion requirements remain unknown. Therefore, Dr Maria Saito-Benz to examine whether transfusion of freshly irradiated vs irradiated and stored RBC components improves cerebral oxygen delivery in preterm infants with anemia.
In a single-center, double-blinded, proof-of-concept study, the researchers included 42 infants who underwent 64 transfusion episodes and randomized them to the intervention (n = 31) or control (n = 33) group. The major outcome assessed was the change in cerebral regional oxygen saturation (crSO2) from baseline (immediately before) to immediately after the transfusion. They further assessed changes in cerebral fractional tissue oxygen extraction (cFTOE) at different time points (immediately after, 24 hours after, and 120 hours or 5 days after transfusion). They measured outcomes by blinded clinicians using near-infrared spectroscopy. They further used the covariate-adjusted linear mixed model to quantify mean treatment effects and account for multiple transfusions in some infants.
Key findings of the study:
- Compared with infants in the control group, the researchers found that those in the intervention group showed a covariate-adjusted mean increase in crSO2 (2.0 percentage points) and a mean decrease in cFTOE (0.02) immediately after transfusion.
- They noted that these differences sustained up to 120 hours or 5 days after transfusion.
- They observed negligible mean changes in crSO2 or cFTOE in infants in the control group at any of the follow-up time points.
The authors concluded, "Results of this trial showed that transfusion of freshly irradiated RBCs conferred a small advantage in cerebral oxygenation for at least 5 days after transfusion compared with transfusion of irradiated and stored RBC components. On-demand irradiation of RBC components may be considered to optimize oxygen delivery in the recipient, but this physiological finding requires further research".
For further information:
Preterm infants, blood transfusion, TA-GVHD, chronic anemia, Freshly irradiated RBC, irradiated and stored RBCs, Intracerebral Oxygenation, cerebral regional oxygen saturation, cerebral fractional tissue oxygen extraction, JAMA Pediatrics.