The rate of increase in hematocrit, humoral vasoactive substances and blood pressure changes in hemodialysis patients treated with recombinant human erythropoietin or blood transfusion.

The role of the rate of increase in hematocrit (Hct) and changes in vasoactive substances as a cause of hypertension induced by the administration of recombinant erythropoietin (r-EPO) were examined in 20 stable hemodialysis (HD) patients. Measurements were made twice at the start of treatment and when the Hct reached 30%. Patients were divided into 2 groups: Group I: 14 patients received r-EPO, 3000 units intravenously three times a week. Group II: 6 patients, needing repeated blood transfusion, were given 2 to 4 units of washed red blood cells during a HD session. The Hct increased by 0.65%/week in Group I and by 6.7%/2 days in Group II. An elevation in blood pressure was not seen in any patient. There was no difference in the levels of renin, angiotensin II, epinephrine, norepinephrine, dopamine, atrial natiuretic peptide (ANP), BUN, creatinine, cardiac thoracic ratio and body weight in any of the groups. In conclusion, elevation of the Hct in HD patients whatever the rate of increase within the 30% Hct range, does not cause an increase in blood pressure. In addition, the levels of vasoactive substances do not change in partially corrected anemic HD patients. As a result blood pressure control can be helped by aiming at the lower target Hct level of around 30%.