Red Blood Cell Transfusions in Preterm Infants: Is There a Difference Between Restrictive and Liberal Criteria?

Abstract

ARTICLE In Reply .— Drs Swamy and Embleton express concern that we may have overinterpreted the findings of our recently published study comparing liberal and restrictive transfusion guidelines in preterm infants. Granted, the primary outcome of the study was the number of red blood cell transfusions, and the sample-size estimation (and therefore the stopping point) for the trial was based on the difference in number of transfusions. However, the secondary outcomes of apnea frequency and severity and brain ultrasound findings were planned from the time that the study was designed. One must always exercise caution in the interpretation of differences in secondary outcomes, and we have tried to do so. The excess of serious brain abnormalities by ultrasound in the restrictive-transfusion group is an important finding, and it would have been irresponsible of us not to report and discuss this finding. The possibility of a type I error remains, however, and we were the first to acknowledge this. However, the probability that the association of restrictive transfusion practice is false and occurred purely by chance is only 1.2% based on our data; this finding would be expected to occur by chance only 1 in 83 times. We will address other specific points raised by Swamy and Embleton. Infants with significant patent …