Dialysate bicarbonate variation in maintenance hemodiafiltration patients: Impact on serum bicarbonate, intradialytic hypotension and interdialytic weight gain

Abstract

DB of 30 mmol/L appears to be associated with SB levels closer to physiological levels than 34 mmol/L. The bicarbonate dialysate, in the tested concentrations, did not appear to have a significant impact on intradialytic hypotension and interdialytic weight gain in maintenance HDF patients.

The impact of dialysis modality and membrane characteristics on intradialytic hypotension

“…A prospective randomized controlled study was conducted to evaluate variations in dialysate bicarbonate concentrations on serum bicarbonate, IDH, and interdialytic weight gain . Patients were randomized into Group 1 (dialysate bicarbonate 30 mmol/L; 46 patients, age range 45.0‐78.0; 52% males) or Group 2 (dialysate bicarbonate 34 mmol/L; 47 patients, age 61.0‐79.8; 60% male).…”

“…Follow‐up time was 9 months. The IDH rate did not differ between the groups (Group 1: 28.0/1000 sessions; Group 2: 27.4/1000 sessions; P =.906) . Some smaller studies may be noted …”

“…The acid base status of patients was heterogeneous and of unknown significance. Patients in group 1 (30 mmol/L bicarbonate dialysate) were younger than group 2 (34 mmol/L bicarbonate dialysate), and produced more acid due to higher protein intake . Dialysis vintage in group 2 was nonsignificantly longer.…”

“…reported in a single‐center study that bicarbonate dialysate had no influence on IDH rates. A notable strength of their study was that all HDF utilized dry acid concentrate (Granudial AF) containing 6 mmol/L of acetate . Additionally, no significant differences in interdialytic weight gain, normalized protein catabolic rate (nPCR), or age‐adjusted Charlson comorbidity index score were reported between both groups .…”

Successful Practice Transitioning Between Hemodialysis and Hemodiafiltration in Outpatient Units: Ten Key Issues for Physicians to Remember

“…While bicarbonate diffusion is relatively ineffective during conventional HD, it is by definition 100% effective with direct infusion of replacement fluid during HDF sessions. Accordingly, substitution (and dialysate) fluid bicarbonate concentration will have to be reduced to <30–35 mEq/L during on‐line HDF sessions to avoid predialysis alkalosis. Furthermore, hemofiltration is not a linear event during HDF; it will be more pronounced in the first hour of treatment with a disproportionate amount net HCO3 anion transfer taking place early on and slowing down with time during treatment.…”