An economical new process for incenter bicarbonate dialysate production: comparison with acetate in a large dialysis population

The impact of dialysis modality and membrane characteristics on intradialytic hypotension

The risk of intradialytic hypotension (IDH) is determined by various factors, among them dialysis modality and dialyzer membrane. We conducted a literature search in PubMed on November 1, 2016 and selected relevant randomized controlled and cross-over trials, and prospective and retrospective cohort studies published in English that investigated the association between IDH and dialysis modality and membrane, respectively. This literature search revealed 669 publications on dialysis modality, 64 on dialysis membrane, and 24 on acetate/bicarbonate dialysate. After omission of duplicate papers and publications outside the scope of this review, we selected 34 papers for inclusion, 19 on dialysis modality, 8 on dialyzer membrane, and 7 on acetate/bicarbonate dialysate. Several strands of evidence indicate that hemodiafiltration (HDF) is associated with lower IDH rates compared to hemodialysis (HD). Data do not show an unequivocal benefit of synthetic vs nonsynthetic dialyzer membranes with respect to IDH occurrence. Acetate-based vs bicarbonate-based dialysate appears to be associated with an increased IDH rate.

A randomized cross-over study comparing the performance of HD integra™ central concentrate system versus pre-produced concentrate in hemodialysis

BACKGROUND

Pre-produced bicarbonate concentrates (PPC) are still widely used in developing countries despite its cost and risk but Central Concentrate System (CCS) is lacking in data to support its wider adoption.

METHODS

We conducted an 8-week randomized crossover study on 16 Hemodialysis machines to compare CCS versus PPC. Performance is assessed by solute concentrations while safety is assessed by microbial count, endotoxin level and adverse event reporting.

RESULTS

Microbial counts and endotoxin levels were monitored on 48 occasions during the 8-week study for the CCS arm of the study. The levels were all below the action limit during the study. No patient reported any adverse events. Dialysate Sodium, Chloride and Bicarbonate concentrations were measured on a total of 128 occasions for each arm of the study. The relative deviations of Sodium, Chloride and Bicarbonate concentration were within ±5% of their nominal values for both. The 95% Confidence Intervals for the ratio of the mean solute concentrations on the CCS to PPC lie within the tolerance limit of ±5%.

CONCLUSION

Modern CCS is bacteriologically safe and its performance statistically equivalent to PPC.

Basics of base in hemodialysis solution: Dialysate buffer production, delivery and decontamination

Hemodialysis requires the use of high volumes of freshly prepared, clean dialysate to foster the removal of low molecular weight metabolites (i.e., urea) and to correct the electrolyte and acid-base imbalance of chronic renal failure. Dialysate is produced by mixing clean, AAMI grade water with both an acid and base concentrate. This purpose of this report is to describe production, mixing and delivery of the buffer component of dialysate, and to also to address the cost, safety and feasibility of producing online bicarbonate. As endotoxin contaminated dialysate has been associated with the release of key mediators in acute and chronic inflammatory diseases associated with long-term hemodialysis therapy, aspects of disinfecting a bicarbonate delivery loop are also addressed.

Bacteria and endotoxin removal from bicarbonate dialysis fluids for use in conventional, high-efficiency, and high-flux hemodialysis

The use of bicarbonate-based dialysis fluids in hemodialysis centers in the United States has increased with the advent of high-efficiency and high-flux hemodialysis. However, bicarbonate dialysis fluids can support rapid bacterial growth and high endotoxin concentrations. This study determined the efficacy of an ultrafiltration device in reducing the bacterial and endotoxin concentrations in bicarbonate dialysis fluids. A polysulfone hollow fiber dialyzer was used to ultrafilter bicarbonate concentrate before entering the central proportioner and bicarbonate dialysate after exiting the proportioner in single patient dialysis machines. Pre- and post-ultrafilter samples were collected for bacterial and endotoxin assays over 10 months. Ultrafiltration of bicarbonate concentrate reduced bacterial and endotoxin concentrations from 288,330 colony forming units (CFU)/ml and 42,804 pg/ml to 0.47 CFU/ml and 109 pg/ml, respectively. Ultrafiltration of the dialysate in single patient systems decreased bacterial and endotoxin concentrations from 15,889 CFU/ml and 1,746 pg/ml to 0.003 CFU/ml and 0.109 pg/ml, respectively. These results demonstrate that ultrafiltration of bicarbonate dialysis fluids is effective in reducing bacterial and endotoxin contamination inherently associated with the use of bicarbonate-based dialysates.