【Abstract】Objective To investigate the effect of the automatic pressure control mode on patients with hemodiafiltration. Methods We enrolled 70 maintenance hemodialysis patients in a single hemodialysis center for this study. They were treated with hemodiafiltration once every two weeks. The volume control mode
for 6 times and automatic pressure control mode for 6 times were used sequentially. Duo pruritus score, the times of high pressure alarm and coagulation were recorded and compared by setting a self crossover control group during treatment. Results The volume of convection was significantly higher in automatic pressure control mode than in volume control mode (16.1±1.8L vs. 13.5±1.4L, t =14.49, P＜0.001). Duo pruritus score was significantly reduced (12.3±1.0 vs. 16.1±2.2, t =-13.57, P＜0.001). The times of high pressure alarm were lower in automatic pressure control mode than in volume control mode (0% vs. 15.47%; P＜0.001). The incidence of coagulation in dialyzer and dialysis tubing were significantly reduced (0 vs. 2.1%, P＜0.001). Conclusions Automatic pressure control mode can increase the amount of convection in hemodiafiltration, reduce the risk of blood clotting, and relieve pruritus symptom.