Device and method for blood treatment with single needle operation

摘要

The present invention relates to a device and a method for blood treatment in a single-needle operating mode. The blood treatment device has an extracorporeal blood circuit comprising a blood supply line leading to the inlet of a blood treatment unit and a blood return line leading away from the outlet of the blood treatment unit. Blood collecting means, for example a blood collecting container, is provided in the blood return line, said means being connected to means for storing gas, for example an air reservoir, by a flow line. The flow connection comprises two line branches, one branch being used to transfer gas from the air reservoir into the blood collecting container and the other branch being used to transfer gas from the blood collecting container into the air reservoir. The connection branch for transferring gas from the air store into the blood collecting container contains means for compressing air, for example a compressor. The device according to the present invention may be operated in such a way that the filling level of the means for collecting blood can be determined as precisely as possible.

主权项

1. A device for blood treatment in a single-needle operation, comprising:
a pump configured to convey blood in an extracorporeal blood circuit to a blood container configured to collect blood, whereby the extracorporeal blood circuit has a blood supply line leading to an inlet of a blood treatment unit and a blood return line departing from an outlet of the blood treatment unit, and the blood container has a closed-off volume; a gas container having a closed-off volume; a first connection path for connecting the blood container to the gas container in such a way that, in an arterial phase, gas expelled from the blood container during the filling of the blood container is transferred to the gas container, the first connection path containing a valve configured to interrupt the connection; a second connection path, containing a gas compressor, for connecting the gas container to the blood container in such a way that, for the purpose of emptying the blood container, gas stored in the gas container is transferred by the gas compressor to the blood container, so that blood can be fed to the extracorporeal blood circuit in the arterial phase and removed from the extracorporeal blood circuit in the venous phase; and a computing arrangement configured to determine blood volume Vblood enclosed in the blood container, wherein the computing arrangement includes:
a first pressure transmitter configured to measure the pressure in the blood container;a second pressure transmitter configured to measure the pressure in the first and second connection paths between the blood container and the gas compressor; anda third pressure transmitter for measuring the pressure in the gas container,wherein the computing arrangement is configured to calculate the blood volume Vblood on the basis of a) the measured pressure in the closed-off volume of the blood container, b) the closed-off volume of the first and second connection paths between blood container and the gas compressor, and c) the closed-off volume of the as container.