Anna Curley, MB MA MD MRCP and Eric Gibson, MD
Approximately 15% of preterm babies receive platelet transfusions. However, can we be certain that absolute platelet count correlates with bleeding, and do prophylactic platelet transfusions prevent or reduce bleeding?
Platelet transfusions are commonly given to prevent bleeding in preterm infants with a low platelet count. However, there is a lack of evidence to support the appropriate platelet count threshold for transfusion. What we know from observational studies, including the original PlaNet-1 trial, is that there appears to be no correlation with the prevention of hemorrhage or with the severity of hemorrhage based on the absolute platelet count in a preterm infant. The PlaNet-2 trial sought to investigate whether transfusing platelets to preterm infants at a higher platelet count threshold count could reduce the risk of major bleeding or death. Interestingly, preterm infants with a low platelet count who were transfused at the higher threshold had a higher risk of morbidity or mortality than those who were not. This suggests that platelets actually have potentially adverse effects in preterm neonates, potentially creating a biologic response in an infant already at high risk of inflammation.