Peripheral hemodynamics, blood viscosity, and the renin-angiotensin system in hemodialysis patients under therapy with recombinant human erythropoietin.

Treatment of renal anemia with rhEPO (120 U/kg body weight/hemodialysis) in transfusion-dependent patients on maintenance hemodialysis led to an increase in blood pressure, regional peripheral resistance and whole blood viscosity. Our results are in agreement with earlier findings that partial correction of renal anemia results in hemodynamic changes characterized by a fall in cardiac output together with an increase in blood pressure due to increased vascular resistance. The increase in whole blood viscosity correlated with the increase in regional peripheral resistance but not with the increase in mean arterial blood pressure. Thus, other regulating factors of vascular resistance must be involved. Correction of renal anemia does not influence the reninangiotensin system. However, peripheral responsiveness of vascular smooth muscles may have changed due to improved tissue oxygenation and thus leading to an increase in vasoconstriction.