Acetate-free biofiltration versus on-line hemodiafiltration: A prospective, cross-over study / 中华肾脏病杂志

ABSTRACT

Objective To compare the therapeutic efficacy between on-line hemodiafiltration (On-line HDF) and acetate-free biofiltration(AFB) in prospective, randomized cross-over way. Methods Twelve stable dialysis patients, aged (49. 7?11. 3) years old and on dialysis for (83. 5?6.7)months, were prospectively, randomizedly treated by AFB, pre-dilution HDF(Pre-HDF), and post-dilution HDF (Post-HDF) for total 36 weeks using F60S high-flux dialyzers. Routine blood biochemical tests, bone metabolism parameters and clearance for both small and larger molecular weight substances were measured at defined intervals. Meanwhile, inter-and intra-dialysis symptoms, hypotension episodes and intra-dialysis arterial blood gas were recorded during the research period. Results Both AFB and on-line HDF were well accepted by the overwhelming majority of patients and dialysis staff. Pre-treatment sodium, total and ionized calcium, chloride, bicarbonate, and urea did not differ within or between three treatment groups, while potassium increased slightly in HDF patients, and phosphate, ?z-microglobulin(?2-m) decreased in all groups. After dialysis, AFB patients exhibited significantly higher bicarbonate concentration and lower potassium level when identical potassium level in dialysate was used. Patients receiving AFB manifested less intra-dialysis PO2 drop and PCO2 rise than those on HDF treatments. HDF treatments could afford higher single-pool and double-pool Kt/V, higher effective urea and ?z-m clearance, and lower total inter-dialysis symptom scores than AFB method. While bone metabolism parameters did not differ between three dialysis modalities, some parameters, such as deoxypyridinoline in HDF and osteocalcin, pyridinoline, deoxypyridinoline in AFB, deteriorated at the end of cross-over. Aluminum concentration decreased progressively to about one-third of pre-study values at the end of study with all three treatments. AFB was associated with a lower pre-dialysis MAP, a smaller drop in MAP during treatment, and similar hypotension episodes compared with two HDF treatments. Albumin concentration showed a trend to decrease during the first 2 months of research period, followed by a slight increase thereafter, but still significantly lower than initial value at the end of cross-over. Conclusions Both on-line HDF and AFB share most of the features of optimal renal replacement therapy. On-line HDF is superior to AFB in such aspects as increased dialysis dose both for small and larger molecular weight toxins and less inter-dialysis symptoms. On the other hand, AFB is associated with smaller effect on arterial blood gas and improved intra-dialysis hemodynamic tolerance. Some dialysis-related symptoms and complications in the case of our AFB practice could be attributable, at least in part, to low dialysate calcium level.