#1705 Central delivery of acid concentrate for haemodialysis: a single-center experience
Authors: Alfano Gaetano , Chiaro Giuseppe D I , Fontana Francesco , Morisi Niccolò , Stipo Lucia , Olmeda Fabio , Cappelli Gianni , Magistroni Riccardo , Donati Gabriele 
Published: May 2024

Abstract

Background and Aims
Dialysate is produced by mixing ultra-purified water with acid and bicarbonate concentrates. Acidic concentrate for hemodialysis can be supplied to the dialysis machine through single-use bags or central concentrate supply. Central delivery of acid concentrate represents an innovation in hemodialysis settings in terms of practicality and eco-sustainability as this system is able to produce and distribute ready-to-use acid dialysis concentrate without the use of acid concentrate bags.
The aim of our study was to compare the amount of material (including packaging) used to supply acid concentrate using a single-use bag (3.8 L or 4.5 L) or central acid supply at the Nephrology Dialysis and Renal Transplant Unit of Azienda Ospedaliero Universitaria di Modena, Modena, Italy. In particular, we reviewed the amount of consumable material before (January-December 2019) and after the implementation of central concentrate supply (July 2022-June 2023). Lastly, a survey was delivered to all dialysis nurses who work in our dialysis Center to evaluate their feedback on central concentrate supply.

Method
Our center is equipped with 46 dialysis stations for patients on chronic hemodialysis that in 2019 delivered 30 000 hemodialysis treatments distributed across morning, afternoon, and evening shifts. Granumix system® (Fresenius Medical Care, Bad Homburg, Germany) was installed in 2022. It produces and distributes acid concentrate fluid with two different concentrations of K+ (2 and 3 mEq/L) and a unique concentration of Ca2+ 1.5 mmol/L (see Figure).

Results
The data collected in 2019 at our Dialysis Center showed that 30 000 acid bags corresponding to 121 000 L of acid concentrate fluid were used to perform hemodialysis. Utilization of bags generated 3 750 kg of pallets, 4 500 kg of plastic and 5 367 kg of boxes. Considering that approximately 10% of the acid concentrate fluid remains unused during each dialysis treatment, approximately 12 000 L of unutilized acid concentrate fluid was wasted.
Following the introduction of the Granumix® system, there was a significant reduction (−80.6%) in the utilization of single-use acid concentrate bags (n = 5 805) and, consequently, in the use of boxes (n = 2 294 vs. n = 11 667) and pallets (n = 40 vs. n = 208). The centralized distribution system of acid concentrate led to a significant reduction in waste including boxed, plastic and pallets (2 642 kg vs. 13 617 kg), disposal of residual acidic solution (2 351 liters vs. 12 100 liters), and handling of materials by dialysis staff (37 522 kg vs. 158 117 kg). Another advantage of this system is the optimized usage of acid concentrate fluid. This system ensures that only the required amount of acid for a specific treatment is used, effectively minimizing waste and decreasing the production of special waste.
The results of the survey (response rate 75%) documented that 79.5% of the nurses received adequate training for its use; 94.9% experienced a reduction in fatigue and 84.6% declared that had more time to dedicate to patients. Lastly, the survey showed that 96.4% of the participants were completely satisfied with the implementation of this new system.

Conclusion
Central delivery of acid concentrate is an innovative solution with eco-sustainable potentialities in reducing the consumable materials and workload in hemodialysis. Overall, most nurses expressed satisfaction as this system reduces dialysis staff workload and allows more time for patient care.