Method and device for determining at least one operating parameter of a device for extracorporeal blood treatment as a function of absolute pressure; the device for extracorporeal blood treatment

摘要

A method and a device for determining an operating parameter of a device for extracorporeal blood treatment as a function of absolute pressure include setting the absolute ambient pressure in a closed container filled partially with air and having an essentially constant container volume by equalization of pressure with respect to the surroundings, and the pressure is maintained by isolating the container. With delivery means, a predetermined sequence of strokes of a liquid is delivered into or out of the container, and the change in the relative container pressure is measured after each delivery stroke. The total volume delivered and the relative pressure are assigned to a value pair, and the absolute pressure and the initial air volume is determined based on the Boyle-Mariotte law by using the value pairs for at least two delivery strokes. The operating parameter is calculated and adjusted as a function of the absolute pressure.