DETECTING PRESSURE PULSES IN A BLOOD PROCESSING APPARATUS

摘要

A monitoring device (7) operates on a pressure signal from a blood processing apparatus, e.g. a dialysis machine, which has an extracorporeal blood circuit connected to a vascular system of a subject for pumping blood through a dialyzer, and a treatment fluid supply system for pumping a treatment fluid through the dialyzer. The monitoring device (7) has a first input block (50) for obtaining a first pressure signal (y) from a first pressure sensor (6a) in the extracorporeal blood circuit, and a second input block (51) for obtaining a second pressure signal (w) from a second pressure sensor (6b) in the treatment fluid supply system. An emulation block (56) generates, as a function of the second pressure signal (w), an emulated first pressure signal (y) which emulates a concurrent signal response of the first pressure sensor (6a), and a filtering block (53) generates a filtered signal (y) as a function of the first pressure signal (y) and the emulated first pressure signal (y), so as to suppress, in the filtered signal (}y) compared to the first pressure signal (y), signal interferences originating from the treatment fluid supply system (1b). A pulse detection block (54) processes the filtered signal (yf) for detection of subject pulses originating from the subject.

主权项

1. A monitoring device comprising:
a first input block configured to obtain a first pressure signal (y) from a first pressure sensor, which is arranged in an extracorporeal blood circuit to detect pressure variations in blood which is pumped through a blood processing unit in the extracorporeal blood circuit by a blood pumping device, wherein the extracorporeal blood circuit is connected to a vascular system of a subject; a second input block configured to obtain a second pressure signal (u) from a second pressure sensor, which is arranged in a treatment fluid supply system to detect pressure variations in a treatment fluid which is pumped through the blood processing unit by the treatment fluid supply system; an emulation block configured to generate, as a function of the second pressure signal (u), an emulated first pressure signal (ŷ) which emulates a concurrent signal response of the first pressure sensor; a filtering block configured to generate a filtered signal (yf) as a function of the first pressure signal (y) and the emulated first pressure signal (ŷ), so as to suppress, in the filtered signal (yf) compared to the first pressure signal (y), signal interferences originating from the treatment fluid supply system; and a pulse detection block configured to process the filtered signal (yf) for detection of subject pulses originating from the subject.