Device for collecting a sample of used dialysis fluid

A blood treatment circuit containing a blood treatment apparatus, the circuit comprising:

• a feedline for supplying fresh treatment liquid to the blood treatment apparatus;
• a main waste liquid discharge line connectable to an outlet of the blood treatment apparatus;
• a secondary waste liquid discharge line, connected to the main waste liquid discharge line, and having an extraction pump therein;
• first measurement means in the main waste liquid discharge line for measuring an amount of liquid flowing through the main waste liquid discharge line and for supplying corresponding data;
• second measurement means in the secondary waste liquid discharge line for measuring an amount of liquid flowing through the secondary waste liquid discharge line and for supplying corresponding data;
• and
• a waste liquid collecting device including:
• a main waste liquid withdrawal line having a first end connectable to the main waste liquid discharge line downstream of the first measurement means, and a second end connectable to a collecting container;
• a secondary waste liquid withdrawal line having a first end connectable to the secondary waste liquid discharge line, downstream of the second measurement means, and a second end connectable to the collecting container;
• and
• means for causing a metered flow of waste liquid into the collecting container through the main waste liquid withdrawal line as a function of the data supplied by the first and second measurement means to thereby collect a sample representative of all waste liquid discharged throughout at least a substantial portion of a treatment session.

A blood treatment circuit connectable to a blood treatment apparatus, the circuit comprising:

• a feedline for connectable to an inlet of the blood treatment apparatus for supplying fresh treatment liquid thereto;
• a main waste liquid discharge line connectable to an outlet of the blood treatment apparatus;
• a secondary waste liquid discharge line, connected to the main waste liquid discharge line, and having an extraction pumps therein;
• first measurement means in the main waste liquid discharge line for measuring an amount of liquid flowing through the main waste liquid discharge line and for supplying corresponding data;
• second measurement means in the secondary waste liquid discharge line for measuring an amount of liquid flowing through the secondary waste liquid discharge line and for supplying corresponding data;
• and
• a waste liquid collecting device including:
• a main waste liquid withdrawal line having a first end connectable to the main waste liquid discharge line downstream of the first measurement means, and a second end connectable to a collecting container;
• a secondary waste liquid withdrawal line having a first end connectable to the secondary waste liquid discharge line, downstream of the second measurement means, and a second end connectable to the collecting container;
• third measurement means in the main waste liquid withdrawal line for measuring an amount of liquid flowing therethrough;
• fourth measurement means in the secondary waste liquid withdrawal line for measuring an amount of liquid therethrough;
• first obturation means arranged in the main waste liquid withdrawal line;
• second obturation means arranged in the secondary waste liquid withdrawal line;
• and
• control means for opening the first obturation means each time the first measurement means has measured a first predetermined amount V of waste liquid and for closing the first obturation means each time the third measurement means has measured a second predetermined amount v of waste liquid, and for opening the second obturation means each time that the second measurement means has measured a first predetermined amount V' of waste liquid, and for closing the second obturation means each time that the fourth measurement means has measured a second predetermined amount v' of waste liquid.