Method for in-line preparation of liquid for an extracorporeal blood treatment apparatus

A method for in-line preparation of liquid for an extracorporeal blood treatment apparatus, which apparatus comprises at least one fluid path from a liquid source to a region for injecting said liquid into an extracorporeal blood circuit and/or into a cardiovascular system of a patient and/or into a chamber of a dialyser, at least a first and a second filtration station placed along said fluid path, the second filtration station operating downstream of the first filtration station, said method comprising the steps of:

• a) placing a filter in correspondence with each station;
• b) sending liquid along said fluid path through said first and said second filtration stations towards said injection region;
• c) removing the filter which operates in correspondence with the first filtration station;
• d) placing, in correspondence with the first filtration station, the filter which operates in correspondence with the second filtration station;
• and
• e) placing a new filter in correspondence with the second filtration station.