Blood hose set, a control device or closed-loop control device, a blood treatment apparatus and a method for the single-needle treatment

A control device for control or closed-loop control of a blood treatment apparatus for treatment of blood by a single-needle method, wherein the blood treatment apparatus to be controlled or closed-loop controlled comprises:

• a blood pump connectable to a blood hose set for conveying blood through the blood hose set, wherein the blood pump is operable in a withdrawal direction;
• a return pump, arranged to convey fluid towards the blood hose set or to a section thereof and/or towards a patient in a return direction during use of the blood treatment apparatus;
• wherein the control device is configured to execute a method by using the blood treatment apparatus, the method encompassing the following steps:
• a) operating the blood pump in a withdrawal direction in which blood is withdrawn from a patient blood circuit and pumped along a patient hose line into the blood hose set;
• and
• b) operating the return pump such that blood is pumped out of the blood hose set and pumped back along the patient hose line into the patient blood circuit;
• wherein:
• steps a) and b) are executed several times alternately;
• blood is not stored in a single-needle chamber provided in a blood path or on a blood side between its withdrawal in step a) and its return in step b);
• and
• the method executed by the control device is controlled and/or monitored by or based on an analysis of pressure measurement values and/or by or based on a motor current or an electricity consumption of at least one pump.