Within the last decade, lower hemoglobin transfusion thresholds have been found to be safe and effective for most patient subpopulations. However, preterm, extremely-low-birth-weight (<1000 g) infants frequently need blood transfusions to treat anemia, and limited evidence suggests that higher hemoglobin transfusion thresholds may lower the risk of mild-to moderate cognitive delay. In order to further examine this hypothesis, researchers randomized 1824 preterm infants (mean birth weight, 756 g; mean gestational age, 25.9 weeks) into two groups—845 preterm infants in a higher hemoglobin transfusion threshold group and 847 infants in a lower hemoglobin transfusion threshold group. At the time of randomization, the mean hemoglobin levels were similar in both groups (13.8 and 13.7 g/dL, respectively), but throughout the treatment phase of the study, hemoglobin levels differed by 1.9 g/dL. The mean number of transfusions in the higher and lower threshold groups was 6.2 and 4.4, respectively. Nevertheless, no differences between death (16.2% and 15.0%, respectively), neurodevelopmental impairment (cognitive delay, cerebral palsy, or hearing or vision loss) (39.6% and 40.3%, respectively), or serious adverse events (22.7% and 21.7%, respectively) were found between the higher vs. lower threshold groups at 22 to 26 months of corrected age. These results confirm the findings of a similar randomized controlled trial completed recently in Europe that higher hemoglobin transfusion thresholds do not improve survival or cognitive development in extremely-low-birth-weight infants.
References:
- Kirpalani H, Bell EF, Hintz SR, Tan S, et al. Higher or lower hemoglobin transfusion thresholds for preterm infants. The New England Journal of Medicine 2020; 383(27); 3639-265
- Franz AR, Engel C, Bassler D, Rüdiger M, et al. Effects of liberal vs restrictive transfusion thresholds on survival and neurocognitive outcomes in extremely low-birth-weight infants: The ETTNO randomized clinical trial. JAMA 2020; 324(6): 560-570
