Effect of Increased Blood Flow Rate on Hemodialysis Tolerability and Achieved Urea Reduction Ratio

Long-term hemodialysis (HD) imposes a significant burden on the quality of life of end-stage kidney disease patients. Optimizing dialysis dose is an important consideration in this population; however, evidence exists that suggests that attainment of population dialysis targets is associated with increased intradialytic complications. In this prospective, before-after study, the blood flow rate (BFR) of 63 maintenance HD patients was increased by 100 mL/min to a maximum BFR of 400 mL/min to determine the impact on patient tolerability and urea reduction ratio (URR) of an increased BFR. Tolerability was assessed by time to recovery (TTR) after dialysis, a validated measure of patient tolerability, and intradialytic complications. Median pre-increase BFR was 252 mL/min compared to 349 mL/min post-increase. Mean TTR decreased from 4.67 h to 4.03 h (P = 0.688). No association was observed between percentage change in BFR (R2 = 0.0) or post-increase BFR (R2 = 0.0) and absolute change in TTR. A significant, positive association was observed between both the absolute and relative changes to BFR and the achieved URR. We found no evidence that increasing BFR by 100 mL/min diminishes patient tolerability.