Method and apparatus for ultrafiltration in hemodialysis

US6042784A · kind A · utility

Assignee

• Fresenius Medical Care Deutschland GmbH · DE

Inventors

• Ralf Wamsiedler · Schweinfurt, DE
• Raimund Walter · Schweinfurt, DE

Key dates

• Filing date: Feb 27, 1998
• Grant date: Mar 28, 2000
• Expiry date: Feb 27, 2018

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61M2205/50
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A method and device for accurately determining the volume of and replacing ultrafiltrate in hemodiafiltration using an ultrafiltrate balance chamber that is subdivided by a movable partition into two balance chamber halves. The two balance-chamber halves being alternately filled, one with ultrafiltrate and the other with substituate, such that the volume of ultrafiltrate is balanced against the volume of substituate. The filling of one chamber with ultrafiltrate or substituate displaces an equal volume of substituate or ultrafiltrate from the other chamber half and diverts the displaced ultrafiltrate or substituate from the balance chamber. The filling volume of the ultrafiltrate balance chamber is used to determine the ultrafiltrate volume or the volume of substituate.