Method for determining concentration; a dialyser

• US 20050236330A1
• Filed: 06/09/2005
• Published: 10/27/2005
• Est. Priority Date: 12/22/2000
• Status: Active Grant

• Current Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius SE & Co. KGaA)
• Original Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius SE & Co. KGaA)
• Inventors: Kraemer, Matthias, Nier, Volker
• Granted Patent: US 7,674,235 B2
• Time in Patent Office: Days
• US Class Current: 210/647
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1609 after use, i.e. downstream of dialyser
• CPC Class Codes: A61M 1/1617 using measurements made during a temporary variation of a characteristic of the fresh dialysis fluid
• CPC Class Codes: A61M 1/3437 downstream of the filter, e.g. post-dilution with filtrate
• CPC Class Codes: A61M 1/3609 Physical characteristics of the blood, e.g. haematocrit, urea
• CPC Class Codes: A61M 1/3675 Deactivation
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2230/20 Blood composition characteristics
• CPC Class Codes: G01N 2800/04 Endocrine or metabolic disorders
• CPC Class Codes: G01N 33/84 involving inorganic compounds or pH

Abstract

A dialyser having a haemo-dialyser and/or a haemo-filter and an extra-corporal blood circulation with which a device for the adding of citrate to the blood is connected upstream and a device for the adding of a substitution solution containing ions to the blood is connected downstream of the haemo-dialyser and/or of the haemo-filter. Ion concentration in the dialysate downstream of the haemo-dialyser and/or of the haemo-filter is detected with respect to the direction of flow of the dialysate. The concentration of the ion, atom or molecule to be determined is reliably ascertained by preventing the complexing of the ion, atom or molecule, at least during the determination of the concentration, by the addition or withdrawal of a substance.

Claims

1-19. -19. (canceled)

20. A dialyser comprising a haemo-dialyser and/or a haemo-filter, an extra-corporal blood circulation with a component for the adding citrate to the blood connected upstream of the haemo-dialyser and/or of the haemo-filter, a component for adding a substitution solution containing ions to the blood connected downstream of the haemo-dialyser and/or of the haemo-filter, and a dialysate line having a detection element for detection of an ion concentration in the dialysate downstream of the haemo-dialyser and/or of the haemo-filter with respect to the direction of flow of the dialysate.

21. The dialyser in accordance with claim 20, wherein the element for the detection of the ion concentration includes at least one ion-sensitive sensor.

22. The dialyser in accordance with claim 21, wherein a test device is provided which performs a function check of the sensor in time intervals or on actuation by an operator.

23. The dialyser in accordance with claim 20, further comprising a pH component for adding a substance are connected to the dialysis line by which pH of the dialysate can be changed.

24. The dialyser in accordance with claim 23, wherein said pH component is disposed such that the adding takes place downstream of the dialyser with respect to the direction of flow.

25. The dialyser in accordance with claim 20, further comprising a flow reducing element by which the dialysate flow can be reduced temporarily.

26. A The dialyser in accordance claim 20, further comprising a control unit which controls the component for adding citrate to the blood in time intervals or on actuation by an operator such that the adding of citrate is temporarily interrupted and which records the concentration value determined by the detection element after the start of the interruption of the citrate addition continuously or in time intervals.

28. The dialyser in accordance with claim 20, further comprising a regulating unit which is connected to the detection element and to the component for adding citrate and/or to the component for adding a substitution solution containing ions and which initiates an increase or a lowering of an amount of citrate and/or of substitution solution containing ions to be added in dependence on a comparison between a nominal value or a nominal value range and the actual value of the ion concentration determined by the detection element.

29. The dialyser in accordance with claim 28, wherein the regulating unit and/or the component for adding citrate are designed such that the concentration of citrate cannot be lowered below a threshold value.

30. The dialyser in accordance with claim 20, further comprising an alarm unit which triggers an alarm on determination of a critical individual measurement of the ion concentration or on determination of a critical trend of individual measurements.

27. (canceled)

31. A dialyser comprising a haemo-dialyser and/or a haemo-filter, an extra-corporal blood circulation with a component for adding citrate to the blood connected upstream of the haemo-dialyser and/or of the haemo-filter, a component for adding a substitution solution containing ions to the blood connected downstream of the haemo-dialyser and/or of the haemo-filter, a dialysate line which has a detection element for the detection of an ion concentration in the dialysate downstream of the haemo-dialyser and/or of the haemo-filter with respect to the direction of flow of the dialysate, and a control unit for controlling the component for adding citrate, said control unit temporarily interrupting the adding of citrate and recording the concentration value in the dialysate as determined by the detection element after the start of the interruption, said control unit thereafter determining an ion concentration in the blood on the basis of the recorded dialysate concentration value.

32. The dialyser in accordance with claim 31, wherein said control unit controls the component for adding citrate in time intervals.

33. The dialyser in accordance with claim 31, wherein said control unit controls the component for adding citrate in response to operator actuation.

34. The dialyser in accordance with claim 31, wherein said control unit records the concentration value determined by the detection element continuously.

35. The dialyser in accordance with claim 31, wherein said control unit records the concentration value determined by the detection element in time intervals.