RESUMO
INTRODUCTION: Hemodialysis (HD) increases the lifespan of chronic kidney disease (CKD) patients. However, HD is only partially effective in replacing renal function. The aim of this study is to compare HD adequacy between sessions with intradialytic exercise with or without blood flow restriction (BFR) with sessions without exercise. METHODS: A crossover study including 22 adult CKD patients on HD. The patients were assigned to BFR (n = 11) or exercise alone group (n = 11). Each patient was submitted to four HD sessions (two with exercise and two control sessions). HD adequacy was assessed by equilibrated Kt/V-urea (eKT/V), single-pool Kt/V-urea (sp-Kt/V), urea and phosphorus rebound, urea reduction ratio (URR) and removal of urea and phosphorus in dialysate. FINDINGS: BFR exercise improved eKt/V and sp-Kt/V (1.32 ± 0.21 vs. 1.10 ± 0.16 for control, P < 0.001; 1.53 ± 0.26 vs. 1.27 ± 0.19 for control, P < 0.001, respectively) and URR (72.5 ± 5.4% vs. 66.1 ± 7.7% for control, P < 0.001). No difference in eKt/V, sp-Kt/V or URR could be detected between exercise alone and control HD sessions. Urea rebound was lower in BFR exercise vs. control sessions (-8.9 ± 9.1% vs. 30.7 ± 12.8%, P < 0.01) and exercise alone vs. control sessions (13.3 ± 29.0% vs. 42.4 ± 15.3%, P < 0.01). Phosphorus rebound was marginally lower in exercise vs. control sessions (14.4 ± 19.1% vs. 28.4 ± 22.1%, P = 0.18). Urea and phosphorus mass removal in dialysate were marginally higher in exercise vs. control sessions (42.2 ± 19.4 g vs. 35.7 ± 12.5 g, P = 0.24; 912.1 ± 360.9 mg vs. 778.6 ± 245.1 mg, P = 0.28). CONCLUSIONS: Intradialytic exercise with BFR was more effective than standard exercise in increasing HD adequacy.