Red Blood Cell Transfusion in Preterm Infants: Current Evidence and Controversies.

The current evidence regarding the indication, advantages and risks of red blood cell transfusion (RBCT) for preterm infants is discussed. This is an important area in Neonatology to be examined given that 90% of extremely low birth weight infants receive RBCT and many controversies remain regarding when to transfuse and the risks of RBCT. The various treatment thresholds and guidelines used are presented and we compare the short-term clinical benefits of liberal and restrictive RBCT in preterm infants; the majority of these are equivocal and sadly long-term outcome data is limited. The latest evidence on how anaemia and blood transfusion affect organ perfusion in preterm infants is presented. This is important when trying to establish the optimal trigger threshold for RBCT in preterm infants, especially because the knowledge about the adaptive physiological responses to anaemia in very low birth weight infants and the effects of RBCT at various levels of anaemia is also inadequate. Further research into the physiological adaptive response to anaemia of varying degrees and to RBCT at different levels of anaemia in preterm infants of different gestational and post-natal ages is needed before we can conclusively guide the optimal timing and trigger thresholds for RBCT in preterm infants.