Carranza MJ, Ceja GA

Language: Spanish
References: 11
Page: 391-394
PDF size: 180.50 Kb.

ABSTRACT

Background: Vascular endothelium responds by releasing vasoactive agents to mechanical stimuli such as shear stress. Endothelial response to shear stress is influenced by blood viscosity. Hematocrit is the major determinant of blood viscosity, because of that in anemia blood viscosity reduces and the effect of this reduction on endothelial function remains unknown.
Objective: To estimate the endothelial response to shear stress in anemic patients.
Patients and method: One hundred and twenty seven anemic patients were included in an open trial in which hemoglobin concentrations and subjacent diseases were recorded. Endothelial function was estimated measuring changes on wrist diastolic blood pressure after 2, 5 and 7 seven minute of endothelial stimulation by mechanical occlusion of the brachial artery, as previously reported.
Results: Endothelial dysfunction was detected in 68 patients (53.5%). Patients were classified in three groups according to the cause of the anemia. Twelve patients had primary hematological diseases, four of them (33.3%) with endothelial dysfunction; twenty subjects had anemia due to chronic renal failure, 10 of them (50%) with endothelial dysfunction, and sixty-eight had anemia secondary to acute bleeding, 38 of them (55.8%) with endothelial dysfunction.
Conclusions: These data suggest that there is a lost of the endothelial relaxing response to shear stress in anemic patients; this may be a homeostatic adjustment to maintain tissue perfusion in this kind of subjects.

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