The clinical efficacy of higher hematocrit levels in children with chronic renal insufficiency and those undergoing dialysis

The optimal hematocrit target range in children with end-stage renal disease, who are receiving recombinant human erythropoietin, is ambiguous due to the lack of compelling, age-appropriate studies. There are a large number of adult and pediatric studies which show that physical performance as well as morbidity and mortality are positively influenced by partial normalization of the hematocrit to 30 vol% to 36 vol%. Cognition studies performed in adults similarly show improvement with partial correction of hematocrit. Normalization of hematocrit studies show lower mortality rates, incremental further improvement in cognition, and greater resolution of cardiac anomalies when compared with patients with partial correction of anemia. Conversely, cardiac death rates may increase in adult patients receiving hemodialysis with preexisting cardiac disease, and there are concerns about the effect of recombinant human erythropoietin on catheter/shunt/fistula patency and on blood pressure. The high cost of recombinant human erythropoietin and established Medicare and Dialysis Outcomes Quality Initiative target hematocrit ranges have also influenced pediatric nephrologists in their assessment of the risk-benefit ratios, despite new adult data suggesting that maintenance of higher hematocrits may be cost-effective. The rationale of using adult-derived hematocrits in children with end-stage renal disease needs to be re-examined in the context of the unique growth and developmental requirements of children. A prospective, multicenter study which determines the relative benefits and risks of age-adjusted hematocrit normalization in children with renal failure is warranted.