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Italian Journal of Vascular and Endovascular Surgery 2015 September;22(3):153-8

Copyright © 2015 EDIZIONI MINERVA MEDICA

lingua: Inglese

Hemodynamic changes conditioned by arteriovenous fistulas for hemodialysis

Stolic R. ¹, Grbic R. ², Odalovic D. ², Smilic L. ²

¹ Faculty of Medicine, University of Kragujevac, Kragujevac, Clinic of Urology and Nephrology, Clinical Center Kragujevac, Kragujevac, Serbia; ² Medical Faculty Pristina/K. Mitrovica, University of Pristina, Pristina, Serbia

After creation of an arteriovenous fistula, a significant increase in blood flow of up to 10-15 times occurs due to rapid decrease vascular resistance. Turbulent blood flow depends on the obstacles within the vessel lumen, upstream of the blood flow, as well as on sudden changes in dimensions of the vessel lumen. Due to such natural events a long stenosis creates less resistance than two short. Therefore correcting the long stenosis may be more beneficial. Hemodynamic changes result in dilatation of the left ventricle, decrease in systemic blood pressure, acceleration of heart rate and increase of natriuretic peptides. Blood flow volume depends on the size of the artery and of the anastomosis. When vessels of smaller lumen are used for the anastomosis, the flow is largely dependent on the flexibility of the venous conduit. For larger arteriotomies, blood flow is regulated by the resistance prevailing in the peripheral vascular bed and collateral circulation. Dialysis needles may affect hemodynamics sometimes, due to microtraumatic punctures in the vascular access and the resulting changes in the rate of blood flow between them. This may cause much hemodynamic stress and so the dialysis needles may be an important cause of vascular access stenosis.