Device to determine and / or monitor the permeability of a fistula from the amplitude of a signal of cardiac pressure during a blood treatment

摘要

Device for performing a procedure for determining and / or monitoring at least one physical state of a patient (1); with a device that is configured to determine an amplitude of a pressure signal (21) during a blood treatment to a patient (1) performed by a blood treatment device (5), which has a blood pump (13) and which is connected to an extracorporeal blood circuit; wherein the pressure signal (21) comprises a cardiac pressure signal (23); and wherein the device is configured to determine the pressure signal (21) by a pressure sensor (11) on the arterial side of the extracorporeal blood circuit; with a device, which is configured to correct the determined value of the amplitude of the pressure signal (21) in a contribution (25) of the blood treatment device with respect to the height of the amplitude of the pressure signal (21) ; and to determine an amplitude of the cardiac pressure signal (23) from the pressure signal (21); and a device, which is configured to evaluate the amplitude of the pressure signal (21) determined over a plurality of dialysis treatments to establish a conclusion about the physical state, where the condition is the development of a stenosis of exit of a fistula; wherein the device is configured to compare with a defined range the amplitude of the cardiac pressure signal (23) determined, during an observation period, which encompasses the plurality of dialysis treatments; where the range is a range in which the amplitude of the cardiac pressure signal should be maintained in the long term.