Comparing Concurrent and Countercurrent Dialysate Flow in Hemodialysis: A Pilot Study on Hyponatremic Patients

Area of Science:

• Nephrology
• Critical Care Medicine
• Neurology

Background:

• Severe hyponatremia poses risks during hemodialysis, including osmotic demyelination syndrome (ODS).
• Concurrent dialysate flow is explored as a method to mitigate these risks.

Purpose of the Study:

• To compare the safety and efficacy of concurrent versus countercurrent dialysate flow in hemodialysis for hyponatremic patients.
• To assess rates of sodium correction, neurological deterioration, and ODS incidence.

Main Methods:

• A randomized controlled trial involving 44 patients with serum sodium < 125 mEq/L undergoing hemodialysis.
• Patients were randomized to concurrent or countercurrent dialysate flow for a 2-hour session.
• Evaluated hydration, hourly sodium levels, neurological status (MMSE), and ODS incidence.

Main Results:

• No significant difference in postdialysis sodium correction rate between concurrent (45.45%) and countercurrent (36.36%) groups (p=0.44).
• Neurological deterioration and ODS were absent in both groups.
• The concurrent group showed a higher proportion of patients without neurological deterioration (73.91% vs. 57.14%).

Conclusions:

• Concurrent dialysate flow is a potentially safer alternative for managing severe hyponatremia during hemodialysis.
• It allows for slower sodium correction, reducing the risk of rapid neurological shifts.
• No increased risk of ODS or neurological deterioration was observed.