Effects of Aerobic Exercise on the Vascular Caliber of the Arteriovenous Fistula in Patients With Chronic Kidney Disease on Hemodialysis: a Randomized Cross-over Study

Hemodialysis is a method responsible for filtering blood and helping to control excess blood fluid and impurities in patients with end-stage chronic kidney disease. The vascular accesses commonly used in this procedure is atribute catheter, which is placed in a large caliber vein, usually jugular or femoral vein, and arteriovenous fistula (AVF). In order to use the AVF in the hemodialysis procedure, a maturation process of the AVF is necessary, characterized by the increase of its caliber, which is accelerated by force exercises located in the AVF region, whose purpose is to promote the vasodilation of the AVF. Systemically performed aerobic exercises are also capable of promoting peripheral vasodilation and their effects on AVF are still unknown. Therefore, this study proposes to evaluate the behavior of the AVF through ultrasound before, during and after performing aerobic exercise on a stationary bicycle. For this, all patient will sign the informed consent form, respond to the International Physical Activity Questionnaire (IPAQ) and questionnaire Kidney Disease Quality of Life (KDQOL-SFTM), and use a pedometer for 7 days to measure the number of steps per day to characterize the sample. Patients will remain in supine position for 5 minutes to measure their vascular caliber of the AVF by echography. After, will be instructed to perform 30 minutes on stationary bike (Model Monark). The AVF vascular caliber will be measured during aerobic exercise. Because it is a cross-over trial, participants will perform the other arm after 7 days.