ANALYSIS OF THE FACTORS INFLUENCING BICARBONATE BALANCE DURING ACETATE-FREE BIOFILTRATION

In acetate-free biofiltration (AFB), the physical separation between t he base losses and the gains could facilitate the modeling of intradia lytic bicarbonate (HCO3) balance. In order to verify this hypothesis, we analyzed in a multicenter study, 126 AFB sessions in which differin g parameters were evaluated (dialysis time, blood flow, ultrafiltratio n, infused HCO3, pre- and post-dialytic HCO3, hematocrit and body wt). Statistical analysis performed with multiple linear regression showed that the post-dialysis HCO3 was significantly dependent (F = 21.68, d .f. 5.95, P < 0.001) directly on the amount of infused HCO3, the level of pre-dialysis HCO3 and the final body weight, and inversely on the dialysis time and the blood flow. HCO3 values predicted by the statist ical model correlated well with the observed ones (r = 0.788, P < 0.00 01) with a mean absolute difference of 2.138 mEq/liter. This modeling approach allowed us to predict, with a computer-aided procedure, the q uantities of HCO3 to be infused to obtain a desired and personalized a cidosis correction.