[Hemodiafiltration with endogenous reinfusion (HFR): biochemical and gas-analytical analysis of the "regenerated" ultrafiltrate]

Abstract

Purpose: During convective techniques, a replacement fluid (R) is necessary that is sterile and pyrogen-free. Using an integrated absorption cartridge, the ultrafiltrate (UF) can be "regenerated"; and used as R. This method is hemodiafiltration with reinfusion (HFR). This study aimed to evaluate the real UF composition after "regeneration" by the resin-charcoal integrated absorption cartridge.

Methods: In eight uremic patients treated with HFR the UF was evaluated at 5, 15, 30, 60, 120, 180 and 240 min after HFR start at the inlet and the outlet resin-charcoal cartridge using the following parameters: urea, creatinine (Cr), uric acid, phosphates, glucose, Beta 2-microglobulin (beta2-m), Na+, K+, Ca++, pH, pCO2, and HCO3-.

Results: Blood (%): urea -61.2 +/- 9.7; Cr -55.4 +/- 8.1; uric acid -69.8 +/- 9.3; phosphates -31.8 +/- 15.7; glucose -8.4 +/- 20.5; Beta2-m -60.3 +/- 11.1; pH +0.76 +/- 0.58; pCO2+ 3.3 +/- 8.5; HCO3- +18.1 +/- 13.5. In UF (outlet vs inlet): urea was not adsorbed; Cr and uric acid were adsorbed; phosphates were not adsorbed; glucose was partially adsorbed (only in the 1st 90 min); Beta2-m was almost totally adsorbed; Na+ and K+ were not adsorbed; for pH, pCO2, and HCO3- there were no significant variations between the inlet and the outlet.

Conclusions: HFR seems to be an easy-to-perform hemodiafiltration (HDF) technique, capable of resolving the typical problems of availability and the production of sterile and ultrapure reinfusion solution.