Abstract:
Background: Large uremic toxins that could not be removed by current hemodialysis cause unsatisfied survival rate in ESRD patients. On-line hemodiafiltration (OL-HDF) with either pre or post-dilution reinfusion mode is a novel treatment that can improve survival. Indeed, post-dilution provide superior efficacy than pre-dilution, because it was not disturbed by high plasma dilution. However, hemoconcentration in the circuit is the major limitation of post-dilution technique. We invented mid-dilution OL-HDF that decreased limitation of hemoconcentration in post-dilution. This study was conducted to compare the efficacy among two OL-HDF modes. Method: In a prospective cross-over study, 12 stable ESRD patients were dialysed with two different infusion modes of OL-HDF in a random sequence. Blood flow rate was set at 400-450 mL/min, substitution flow rate was set at the upper limit of each mode (300, and 120 mL/min during mid-dilution, and post-dilution). Results: The large molecule removal represented by total plasma water [beta]2 microglobulin clearance in post-dilution was comparable with mid-dilution (156.5+-19.7 vs 143.6+-17.4 mL/min, NS),The urea clearance of mid-dilution HDF did not differ from post-dilution (427.2+-73.5 vs 409.2 +-39.3mL/min,NS). Creatinine clearance and phosphate clearance were did not differ between 2 modes. ( 319.5+-41.6 vs 324.4+-36.8 , 384.5+-10.7 vs 413.4+-10.5 ,NS). Interestingly, albumin loss in mid-dilution was significantly lower than post-dilution (4.7+-1.7 vs 3.1+-1.4 g, p =0.04). Conclusion: Mid-dilution OL-HDF appears to provide comparable high efficacy in large molecule removal with the post-dilution mode, but with a lesser albumin loss. Thus, the mid-dilution technique would offer a potential role in preventing or retarding dialysis-related long term complications in hemodialysis patients.