Zero Diffusive Sodium Balance in Hemodialysis Provided by an Algorithm-Based Electrolyte Balancing Controller: A...

Area of Science:

• Nephrology
• Biomedical Engineering
• Clinical Trials

Background:

• Fluid volume homeostasis remains a significant challenge for end-stage kidney disease (ESKD) patients undergoing intermittent hemodialysis (HD) or hemodiafiltration (HDF).
• Current practices often overlook individualized intradialytic sodium transfer, applying uniform dialysate sodium levels that may not align with patient-specific plasma sodium concentrations.
• Deviations in the dialysate-plasma sodium gradient can lead to intradialytic sodium loading or excessive removal, impacting patient outcomes and comfort.

Purpose of the Study:

• To evaluate a novel conductivity-based electrolyte balancing control (EBC) algorithm designed to achieve
• zero diffusive sodium balance
• in HD and online HDF treatments.
• To assess the efficacy of the EBC module in automatically individualizing dialysate sodium levels without requiring predialytic plasma sodium measurements.
• To determine the impact of the EBC module on intradialytic plasma sodium concentration variability and overall patient tolerance.

Main Methods:

• A prospective clinical trial was conducted in two phases: a standard care phase with conventional fixed-sodium dialysate and a controlled care phase with the EBC module activated.
• The EBC algorithm, embedded in a hemodialysis machine, utilized dialysate conductivity to dynamically adjust sodium delivery.
• Intradialytic plasma sodium concentrations and clinical manifestations were monitored throughout both phases.

Main Results:

• The EBC module demonstrated a reduction in the variability of intradialytic plasma sodium concentration shifts.
• A small but statistically significant increase in mean plasma sodium levels was observed, attributed to the algorithm's conductivity-based design.
• No adverse clinical manifestations were reported, suggesting good intradialytic tolerance despite the observed sodium increase.

Conclusions:

• The EBC module effectively individualizes dialysate sodium delivery based on patient conductivity, facilitating better fluid management and sodium balance control in HD/HDF.
• The algorithm shows potential for improving intradialytic tolerance by minimizing unwanted sodium shifts.
• Further refinement, potentially by incorporating potassium shifts, could optimize sodium balance and enhance the clinical utility of this automated system.