On-line hemodiafiltration: technique and therapy.

Area of Science:

• Nephrology
• Biomedical Engineering

Background:

• On-line hemodiafiltration (HDF) represents an advanced form of renal replacement therapy.
• It offers a broader spectrum of blood purification compared to conventional dialysis methods.
• Current HDF systems utilize state-of-the-art dialysis membranes and treatment technologies for enhanced biocompatibility.

Purpose of the Study:

• To evaluate the efficacy and safety of on-line hemodiafiltration.
• To assess the economic viability and therapeutic benefits of HDF.
• To detail the optimal parameters and preparation methods for on-line HDF.

Main Methods:

• On-line HDF involves generating sterile, pyrogen-free substitution fluid from dialysate via stepwise ultrafiltration.
• Substitution fluid is administered, preferably in postdilution mode, to replace ultrafiltered volume (20-30 liters per treatment).
• Key factors for optimal substitution fluid preparation include water quality, concentrate purity, ultrafilter integrity, and microbiological control of the system.

Main Results:

• On-line HDF achieves a greater clearance of solutes across a wide molecular weight range compared to high-flux dialysis with identical membranes.
• The biocompatibility of on-line HDF is comparable to the highest standards achievable with current technologies.
• Clinical studies and long-term user data confirm the safety of on-line prepared substitution fluid.

Conclusions:

• On-line HDF provides superior blood purification and therapeutic benefits that justify its costs.
• Optimal performance requires maximizing the ultrafiltration rate relative to blood flow rate.
• The preparation of sterile, pyrogen-free substitution fluid is critical for the clinical safety and efficacy of on-line HDF.