Amid A, (2016) Blood, (Link to abstract)
Ali Amid, Melanie Kirby-Allen, and Isaac Odame evaluated a new transfusion strategy in hemoglobin Barts hydrops fetalis or homozygous α0-thalassemia. They described that a traditional transfusion strategy adopted from transfusion-dependent beta-thalassemia targeting a hemoglobin >100 g/L led to persistent chronic hemolysis, splenomegaly, elevated HbH, and high erythropoietin as a marker for tissue hypoxia. The HbH percentage ranged from 24 to 64%. The authors estimated that the functional hemoglobin was in the range of 43 to 79 g/L. The authors suggest that homozygous α0-thalassemia is a hemolytic disease with robust erythropoiesis in contrast to transfusion-dependent beta-thalassemia and therefore a more aggressive transfusion strategy might be needed to suppress HbH formation. A new transfusion strategy aiming at hemoglobin levels >100 g/L and HbH percentages <15% was implemented leading to decrease in spleen size, reticulocyte counts, hemolytic parameters, and erythropoietin levels. The more aggressive transfusion protocol led to an increase in red blood cell transfusion volume form 208 ml/kg per year to 286 ml/kg.
* Implementation of a more aggressive transfusion protocol targeting HbH<15% and hemoglobin 100 g/L in hemoglobin Barts hydrops fetalis led to decrease in hemolytic parameters, spleen size, and markers of tissue hypoxia but this study did not report on clinical benefits. It is unclear if the increase in transfusion burden and iron overload needing increase in chelation is outweighed by clinical improvements.