Variation in Transfusion Requirements Among Children With Thalassemia on Regular Transfusion Programs: Which Formula Closely Predicts the Actual Requirements?

BACKGROUND

Various different formulae are used to calculate blood transfusion volumes in thalassemia. Using the right formula will avoid iron overload and complications of undertransfusion.

OBSERVATIONS

Five years of transfusion data in 11 children with thalassemia showed that no single formula-calculated transfusion volumes accurately. The formula used in the United Kingdom with a hematocrit of the transfused blood of 0.6: (0.4×body weight×desired raise in hemoglobin [g/L]) yielded a volume closest to empirically determined requirements on average. Transfusion factors ranging from 0.3 to 0.48 were calculated as necessary to achieve the required volume for the individual patient.

CONCLUSIONS

To meet transfusion requirements, individualization of formulas by establishment of the transfusion factor for each patient is helpful.