Sodium setpoint and gradient in bicarbonate hemodialysis
Carlo Basile1, Pasquale Libutti, Piero Lisi
1Nephrology and Dialysis Unit, Department of Medicine, Miulli General Hospital, Acquaviva delle Fonti - Italy.
Journal of Nephrology
|November 14, 2012
Summary
Hemodialysis patients have a stable individual osmolar setpoint, crucial for personalizing dialysate sodium. This study confirms this setpoint, aiding in fine-tuning sodium balance during treatment.
Area of Science:
- Nephrology
- Clinical Chemistry
Background:
- Individualizing dialysate sodium concentrations in hemodialysis (HD) is essential.
- Understanding the sodium diffusive gradient is key for intradialytic sodium mass balance (MB).
Purpose of the Study:
- To demonstrate an individual osmolar setpoint in hemodialysis patients.
- To investigate the relationship between dialysate sodium, plasma sodium, and sodium mass balance.
Main Methods:
- Retrospective analysis of plasma sodium concentrations from a 6-year HD database.
- Prospective study of intradialytic sodium kinetics in 48 HD patients using direct potentiometry.
Main Results:
- Long-term follow-up showed a stable, individual plasma sodium concentration in HD patients.
- A significant sodium transfer from dialysate to plasma was observed, influenced by the diffusion gradient and ultrafiltration volume.
Conclusions:
- A consistent, individual osmolar setpoint in hemodialysis patients was demonstrated.
- A dialysate sodium concentration of 140 mmol/L creates a measurable dialysate-to-plasma sodium gradient.
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