BP Rises with ESAs Not Relate to Vasoconstriction
PHILADELPHIA—New study findings may narrow down the possible causes of increased blood pressure (BP) result from the use of erythropoiesis stimulating agents (ESAs) to correct renal anemia, according to a report presented at Kidney Week 2011.
The researchers who conducted the study noted that such BP rises occur in up to 35% of patients and it is unclear whether this is due to increased blood viscosity, increased blood volume, reduction of hypoxic vasodilation, and/or ESA-induced vasoconstriction.
In a study of 163 critically ill patients with acute kidney injury, the investigators found that using high doses of epoetin did not increase BP for up to 72 hours after administration, demonstrating that epoetin does not have an acute vasoconstrictor effect in these patients.
For the study, Zoltan H. Endre, MD, of the University of Otego Christchurch, New Zealand, and colleagues randomized patients to two doses of IV epoetin 500 U/kg 24 hours apart or placebo. The researchers recorded mean arterial pressure (MAP) and norepinephrine equivalent dose (NED) hourly.
At baseline, MAP was 78 mm Hg in the epoetin group and 81 mm Hg in the placebo group, a nonsignificant difference. At four hours after the first drug dose, the investigators observed no significant difference between study arms with respect to change in MAP (6.5 vs. 8.4 mm Hg), change in norepinephrine equivalent dose (-0.8 vs. -0.1 µg/min), or in the change in MAP adjusted for change in norepinephrine equivalent dose. They also noted no differences after 24 or 72 hours, or four or 24 hours after the second dose. Hemoglobin level and hematocrit were unchanged.