SP491EFFECTS OF DECREASING DIALYSIS FLUID FLOW RATE ON DIALYSIS EFFICACY AND INTERDIALYTIC WEIGHT GAIN IN CHRONIC PATIENTS WITH HEMODIALYSIS - FLUGAIN Study

Abstract

INTRODUCTION AND AIMS: Hemodialysis (HD) is classically performed with dialysis fluid flow (Qd) at 500 mL/min, we consider that in HD with modern high flux dialyzers, Qd can be adjusted to body size of patients without impact on dialysis efficacy.Our aim was to determine if there is a difference in dialysis efficacy patients treated with dialysate flow (Qd) of 400 mL/min vs Qd of 500 mL/min. METHODS: After ethical committee approval, we performed a cross-over randomized trial in patients in End-stage kidney disease in HD.For inclusion, subjects were required to be older than 18 years old, with a stable prescription of HD 4 hours thrice weekly, prescribed Kt/V higher than 1.2 and post-dialysis weight lower or equal than 65Kg on the previous month. In a cross-over trial, each patient was divided into two groups: Group A with dialysis fluid flow rate (Qd) at 500mL/min and group B with Qd at 400mL/min. Each group was assigned for 4 weeks to each patient. Patient data included demographic characteristics, weight gain and weekly serum sodium, chloride and Kt/V and Monthly measurements of hemoglobin, serum phosphorus and potassium. RESULTS: A total of 46 patients were enrolled (25 men with an average age of 61.8 years old). 24 (52.2%) were first in the Qd 400mL/min group and 22 (47.8%) in the Qd 500mL/min group. Kt/V, interdialytic weight gain, blood pressure and electrolytes were similar between the two groups. Without statistically significant differences. However, the water consumption by session in the first group (Qd 500mL/min) was 120L while 96L in the second group (Qd 400mL/min). CONCLUSIONS: The reduction in the dialysis fluid flow rate in small patients has no impact in terms of Kt/V, interdialytic weight gain, blood pressure and electrolytes, but reduces considerably the amount of water per dialysis session. We present a different use of dialysate flow rates, considering that it would lead to significant water conservation without compromise on dialysis efficacy in small patients. We believe that further investigation of reduced Qd in different populations is needed to broaden our understanding of how we can use these techniques in order to reduce water consumption during chronic HD while still ensuring optimum efficacy of the therapy. Comparison between Qd 400 mL/min and 500 mL/min