Patent ID: 7704213
Filing Date: 2010-04-27
Classification: A61M,G01F

Abstract:
1. A method of determining a blood flow rate Q F in a blood-carrying line that is coupled to an extracorporeal blood treatment device through an arterial line and a venous line using a processing unit, a portion of blood in said blood-carrying line being branched off at a first location through said arterial line and being returned to said blood-carrying line at a second location through said venous line such that said portion of blood passes from said arterial line to said extracorporeal blood treatment device and then to said venous line, the method comprising the steps of: determining, using a measurement means a physicochemical variable Y of the blood, which is constant over a period of time for a measurement interval, in the arterial line upstream of said extracorporeal blood treatment device as having the value Y A and in the venous line downstream of said extracorporeal blood treatment device as having value Y V , determining, using said processing unit a net rate dX/dt of a variable X derived from the physicochemical variable Y into or out of the blood-carrying line during the measurement interval from the values Y