Acetate-Free Hemodialysis: A Feasibility Study on a Technical Alternative to Bicarbonate Dialysis

Abstract

This study aimed at evaluating the feasibility of an acetate-free hemodialysis (AFHD) technique, comparing it with acetate-free biofiltration (AFB) and bicarbonate dialysis (BD). The assessment of the parameters concerned: electrolyte kinetics (Na⁺, K⁺), acid-base balance (HCO₃^–, pH), dialysis efficiency (Kt/V), serum β₂-microglobulin reduction ratio, nutritional status (normalized protein catabolic rate, serum albumin and total proteins, body mass index), hemopoietic status (hemoglobin, hematocrit), and some clinical parameters (systolic and diastolic blood pressures, heart rate, percent blood volume reduction measured by Hemoscan^®). Nine patients participated in this study which was conducted using a Latin square randomized experimental design. The results of the last week of each month of the study (1 month for each technique) were analyzed by means of Anova for repeated measures. The different treatments were comparable with regard to the main dialysis parameters such as blood flow (320 ml/min) and weight loss rate (0.6 ± 0.1 kg/h), while dialysis length and dialysate conductivities were different, depending on the dialysis technique. Electrolyte kinetics and acid-base balance were similar during the three periods. The dialysis efficiency for small molecules (Kt/V of urea) was similar (between 1.4 and 1.6); however, AFB seemed to show a higher β₂-microglobulin reduction rate (47.6 ± 4 vs. 4.3 ± 10% for AFHD and vs. 9.9 ± 5% for BD; p < 0.001). The nutritional and hemopoietic status maintained stable, and the hemodynamic parameters were comparable during all periods. The percent blood volume reduction at the end of the treatments was not statistically different (–14.9 ± 9.4% in AFB, –12.1 ± 5.1% in AFHD, and –12.2 ± 4.4% in BD), and these results could explain the similar hemodynamic behavior during the three periods. In conclusion, AFHD appears to be a safe technique which has all positive effects of AFB and the low costs of BD. In our opinion, it could be used in patients with few clinical impairments, usually treated with hemodialysis, in whom a biocompatible treatment is indicated.