Short-Term Physiological Effects of Red Blood Cell Transfusion in Very Low Birth Weight Infants: A Retrospective Cohort Study

Background/Objectives: While packed red blood cell transfusions are commonly administered in anemic neonates, transfusion strategies in preterm infants have been the subject of debate for decades, particularly due to questionable long-term benefits and limited evidence regarding short-term physiological effects. In non-intubated preterm infants, established transfusion thresholds are considered, but individual clinical judgment often plays an important role in the final decision. This study aims to assess the short-term cardiorespiratory effects of red blood cell transfusions in non-intubated very-low-birth-weight (VLBW) infants who were either spontaneously breathing or receiving non-invasive respiratory support. Methods: Retrospective, single-center analysis of 68 VLBW infants (<1500 g) who received 99 red blood cell transfusions between 2019 and 2023. Cardiorespiratory parameters were observed over a 24 h period before and after transfusion. Results: Following transfusion, there was a significant decrease in the frequency of bradycardia events per 24 h (6.51 ± 5.55 to 4.24 ± 3.8; p = 0.004), accompanied by an improvement in the depth of oxygen desaturations (78.7 ± 4.18 to 81.0 ± 3.71; p = 0.001). No significant changes were detected in the desaturation frequency, FiO2 or heart rate. Conclusions: In clinically stable very-low-birth-weight infants receiving non-invasive ventilatory support, packed red blood cell transfusion is associated with modest, short-term improvements in cardiorespiratory stability. However, these effects are limited in scope. Further research is needed to identify which patient subgroups derive the most significant benefit from these transfusions.