Reticulocyte Count: The Forgotten Factor in Transfusion Decisions for Extremely Low Birth Weight Infants.

Objective: Extremely low birth weight (ELBW) infants often receive transfusions of packed red blood cells (PRBCs). Long-term outcomes of infants treated with liberal versus restricted transfusion criteria have been evaluated with conflicting results. Clinicians incorporate a reticulocyte count (RC) in their transfusion decisions. There is a lack of information on reference ranges for RCs in growing ELBW infants and whether infant's chronologic age or corrected gestational age (GA) generates a specific trend in the RCs. Our aim was to evaluate the levels of RCs obtained from ELBW infants over the course of the initial hospitalization.

Study Design: A retrospective chart review of ELBW infants treated in the neonatal intensive care unit (NICU) and had RCs performed. We analyzed the RCs to observe trends based on the chronologic age and corrected GA.

Results: A total of 738 RCs were analyzed. A positive trend in RCs that reached a peak at 32 to 34 weeks' corrected GA and then experienced a downward trend was observed.

Conclusion: Our report examines a very common hematologic test that is theoretically helpful but is in need of guidelines concerning the appropriate frequency of testing and its utility in making transfusion decisions in ELBW infants.

Key Points: · RCs should help in making transfusion decisions for ELBW infants.. · No current reference ranges for RC in this population.. · No current reference ranges for RC based on GA and postnatal age..