In this single repeated measures study, an examination was done on the effects of dialysate flow rate on dialysis adequacy and fatigue in patients receiving hemodialysis.

This study was a prospective single center study in which repeated measures analysis of variance were used to compare Kt/V urea (Kt/V) and urea reduction ratio (URR) as dialysis adequacy measures and level of fatigue at different dialysate flow rates: twice as fast as the participant’s own blood flow, 500 mL/min, and 700 mL/min. Thirty-seven hemodialysis patients received all three dialysate flow rates using counterbalancing.

The Kt/V (M±SD) was 1.40±0.25 at twice the blood flow rate, 1.41±0.23 at 500 mL/min, and 1.46±0.24 at 700 mL/min. The URR (M±SD) was 68.20±5.90 at twice the blood flow rate, 68.67±5.22 at 500 mL/min, and 70.11±5.13 at 700 mL/min. When dialysate flow rate was increased from twice the blood flow rate to 700 mL/min and from 500 mL/min to 700 mL/min, Kt/V and URR showed relative gains. There was no difference in fatigue according to dialysate flow rate.

Increasing the dialysate flow rate to 700 mL/min is associated with a significant nicrease in dialysis adequacy. Hemodialysis with a dialysate flow rate of 700 mL/min should be considered in selected patients not achieving adequacy despite extended treatment times and optimized blood flow rate.