Patent ID: 8180443

Claim:
A device for monitoring vascular access during an extracorporeal blood treatment, in which a patient's blood is withdrawn from the patient via an arterial tubular conduit comprising an arterial patient connector with an arterial puncture cannula, the patient's blood is returned to the patient via a venous tubular conduit comprising a venous patient connector with a venous puncture cannula, and the blood is conveyed by a pump in the arterial tubular conduit or the venous tubular conduit that generates triboelectric charges during operation, the device comprising: a first contact element adapted to be placed on a patient's skin to produce an electrical connection to the patient's skin, and a second contact element adapted to be in contact with a fluid flowing in a dialysis fluid circuit or a fluid flowing in a filtrate fluid circuit; a measurement unit configured to measure at least one of: an AC voltage, an alternating current, and a derived electrical variable, each resulting only from the triboelectric charges generated by the pump, wherein the AC voltage, the alternating current, or the derived electrical variable is measured between the first contact element and the second contact element; and an evaluation unit configured to evaluate the at least one of: the measured AC voltage, the measured alternating current, and the measured derived electrical variable, wherein when there is a change in an amplitude of the at least one of: the measured AC voltage, the measured alternating current, and the measured derived electrical variable, this is a first indication of an incorrect vascular access.