Device for monitoring an infusion pump

Method and device for monitoring of an infusion pump in a machine for hemodiafiltration or hemofiltration. The machine comprises a first flow circuit for a dialysis solution with a flowmeter arranged in the flow circuit. In addition, there is a second flow circuit for blood. A dialyser or hemofilter is divided by means of a semi-permeable membrane into a first chamber which is connected to the first flow circuit and a second chamber which is connected to the second flow circuit. In addition, there is a third flow circuit from an outlet for dialysis solution in the first flow circuit to a connection in the second flow circuit and comprising an infusion pump. The dialyser is disconnected by means of a valve from the first flow circuit so that the infusion pump is connected in series with the flowmeter in the first flow circuit. The monitoring of the infusion pump takes place by comparing the expected flow through the infusion pump with the measured flow through the flowmeter.