The Online Purification Cascade (OPC) covers the whole production of dialysis and substitution fluids from tap water through several purification steps to the patient – with emphasis on ONLINE Haemodiafiltration (HDF) as the reference treatment.

The Online Purification Cascade

• applies Fresenius Medical Care’s high quality standard to dialysis fluids production.
• is fully based on Fresenius Medical Care technology and know-how.
• includes integrated service and support packages from planning to maintenance.

A dialysis patient who is treated 3 times a week with approximately 150 litres of dialysis fluid is exposed to almost 24,000 litres each year.

While tap water in most municipalities easily meets drinking water standards, it would cause severe side effects if used directly for dialysis. In order to be brought to use for blood purification, the tap water itself must be treated to achieve the chemical and microbial degree of purity required for dialysis and substitution fluids. Here is where the Online Purification Cascade starts: a reliable and effective process to transform tap water into sterile fluid ready for infusion.

In order to achieve the necessary degree of purification, the OPC comprises a series of devices each addressing different decontamination issues. Purification starts in the water pre-treatment system, followed by the reverse osmosis unit. Finally, the water runs through the distribution loop to the fluid filters in the dialysis machine. The whole cascade from reverse osmosis to the distribution loop and
the dialysis machine has been thoroughly validated and certified as a combination of medical devices.

For safety and security, the system has numerous built-in redundancies for fail-safe online production of substitution fluid.

But even in a closed system, there is still a risk of contamination. Water may not stay pure, so utmost care must be taken to prevent microbes from recolonising, demanding the right materials, design and installation, but also planned monitoring and control. All components of the Online Purification Cascade are designed to reduce risk, provide ease of use and maximise security.