Dialysis Adequacy, Dialyzer Clearance, and Strategies to Achieve Target: A Nationwide Multicenter Study

Abstract

Background: Adequate dialysis improves patients’ outcome. Single pool Kt/V (spKt/V) > 1.4 is recommended as an index of adequacy. In this study, we assessed dialysis adequacy, the etiologies of under dialysis and the solutions. Methods: In a multicenter nationwide cross-sectional study, 7,009 point-prevalent hemodialysis patients were evaluated for dialysis adequacy, blood flow rate (BFR), total body water (V), and the required dialyzer KoA. Results: The mean age was 57.2 ± 14.9 years. About 90% of the patients were dialyzed 12 hours per week, but only 27.4% had spKt/V > 1.4. The mean BFR was 297.58 ± 28.6 cc/min (4.66 ± 0.84 cc/min/kg). The mean KoA was 787.28 ± 137.19 cc/min. Those with spKt/V > 1.4 had smaller body size and higher BFR. To achieve spKt/V of 1.4, 79.3% of the patients required dialyzer, with KoA of 700 cc/min or more with an average BFR of 400 cc/min. Of the patients, 17.8% had to use either higher BFR (≥ 400 cc/min) and KoA (≥ 1400 cc/min), or be dialyzed for at least four sessions per week, the latter seemed more feasible. Conclusions: Low BFR and inappropriate dialyzer choice were the leading causes of inadequate dialysis. With respect to attaining the most adequate dialysis based on solute removal, it seems reasonable to evaluate the causes of low BFR and access dysfunction. Better nursing education and decreasing catheter use may help overcome the barriers.