Device for determining a concentration of a constituent of blood in a hose line

• US 8,792,089 B2
• Filed: 07/20/2012
• Issued: 07/29/2014
• Est. Priority Date: 07/21/2011
• Status: Expired due to Fees

• Current Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius Medical Care AG)
• Original Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius Medical Care AG)
• Inventors: Zhang, Wei, Schulte, Elke, Kaiser, Martin, Mueller, Carsten, Klein, Tom, Zerle, Stefan, Bardorz, Christoph, Stuehler, Stefan
• Primary Examiner(s): Punnoose, Roy M
• Application Number:
  US13/554,145
• Publication Number:
  US 20130033697A1
• Time in Patent Office: 739 Days
• Field of Search: 356/39, 600/322
• US Class Current: 356/39
• CPC Class Codes: A61B 5/14557 specially adapted to extracorporeal circuits
• CPC Class Codes: A61M 1/367 Circuit parts not covered by the preceding subgroups of group A61M1/3621
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2230/20 Blood composition characteristics
• CPC Class Codes: G01N 2021/0378 Shapes
• CPC Class Codes: G01N 2021/3144 for oxymetry
• CPC Class Codes: G01N 21/05 Flow-through cuvettes G01N21/09 takes precedence; handling fluid samples G01N1/10
• CPC Class Codes: G01N 21/31 Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 33/49 Blood chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80

Abstract

A device for determining the concentration of a constituent of blood in a hose line, in particular in the hose line of an extracorporeal blood circuit of an extracorporeal blood treatment apparatus, includes a clamping unit having an actuation mechanism configured to apply a clamping force such that first and second receiving elements are moved towards one another from a first position releasing the hose line into a second position clamping the hose line, in which the drive of the actuation mechanism takes place with an electric motor, and a monitoring unit configured to detect a hose line inserted into the receiving elements. A method for detecting a hose line in a clamping unit of a device for determining the concentration of a blood constituent in the hose line is also described. Automation of the measurement of the blood parameters is thus possible.

Claims

1. A device for determining a concentration of a constituent of blood in a hose line of an extracorporeal blood circuit of an extracorporeal blood treatment apparatus, comprising:

a clamping unit comprising a first receiving element and a second receiving element configured to clamp the hose line such that the hose line clamped between the first and second receiving elements has a square cross-section;

a measurement unit configured to couple electromagnetic radiation through the hose line into the blood and measure the electromagnetic radiation emerging through the hose line from the blood; and

a computing and evaluation unit configured to determine the concentration of a constituent of blood, said computing and evaluation unit cooperating with the measurement unit;

wherein the clamping unit comprises an actuation mechanism configured to apply a clamping force such that the first and second receiving elements are moved towards one another from a first position releasing the hose line into a second position clamping the hose line, the actuation mechanism comprising an electric motor for driving the actuation mechanism.

2. The device according to claim 1, further comprising:

a monitoring unit configured to detect a hose line inserted into the receiving elements.

3. The device according to claim 2, wherein the monitoring unit comprises a unit for measuring one of (a) a motor current of the electric motor for driving the actuation mechanism of the clamping unit and (b) a variable correlating with the motor current, and a computing and evaluation unit configured to detect a hose line inserted into the receiving elements on a basis of a change in one of (a) the measured motor current and (b) the measured variable correlating with the motor current.

4. The device according to claim 3, wherein the monitoring unit is configured to correct with a correction value the motor current measured by the unit for measuring the motor current, the correction value being obtained in a calibration measurement when the hose line is not inserted into the clamping unit.

5. The device according to claim 3, wherein the monitoring unit comprises a unit for measuring a path covered by the receiving elements, and the computing and evaluation unit of the monitoring unit is configured to evaluate the motor current as a function of the path covered by the receiving elements.

6. The device according to claim 5, wherein the computing and evaluation unit of the monitoring unit is configured to compare with a preset threshold value at least one of (a) an integral of the motor current and (b) a maximum value of the motor current over a preset path covered by the receiving elements, it being concluded that one of (i) a hose line is inserted into the receiving elements when the threshold value is exceeded, and (ii) a specific first hose line is inserted into the receiving elements when the threshold value is exceeded and a specific second hose line is inserted into the receiving elements when the threshold value is fallen below, the first and second hose line being different hose lines.

7. The device according to claim 1, wherein the first receiving element comprises two plane contact faces at right angles to one another, and the second receiving element comprises two plane contact faces at right angles to one another, wherein the first and second receiving elements can be moved towards one another on an axis that encloses an angle of 45°

with the plane contact faces of the first and second receiving elements.

8. The device according to claim 7, wherein the first receiving element comprises semi-cylindrical contact faces on both sides of the plane contact faces of the first receiving element, and the second receiving element comprises semi-cylindrical contact faces on both sides of the plane contact faces of the second receiving element.

9. The device according to claim 8, wherein the first receiving element comprises a transition section on both sides of the plane contact faces configured to transform continuously the plane contact faces into the semi-cylindrical contact faces.

10. The device according to claim 1, wherein the measurement unit comprises light emitters and light detectors disposed in the first and second receiving elements.

11. The device according to claim 10, wherein plane contact faces of the receiving elements comprise light outlet and light inlet openings assigned to the light emitters and the light detectors.

12. The device according to claim 10, wherein at least one group of two light emitters is assigned to at least one light detector.

13. The device according to claim 12, wherein the two light emitters of the at least one group of light emitters are disposed on sides lying opposite one another.

14. A method for detecting a hose line of an extracorporeal blood circuit of an extracorporeal blood treatment apparatus, in a clamping unit of a device for determining a concentration of a blood constituent, the clamping unit comprising a first receiving element and a second receiving element for clamping the hose line, and an actuation mechanism comprising an electric motor for driving the actuation mechanism, the method comprising:

applying a clamping force by the actuation mechanism such that the first and second receiving elements are moved out of a first position releasing the hose line into a second position clamping the hose line;

measuring one of (a) a motor current and (b) a variable correlating with the motor current, of the electric motor for driving the actuation mechanism of the clamping unit; and

detecting the hose line inserted into the receiving elements on a basis of a change in one of (a) the measured motor current and (b) the measured variable correlating with the motor current.

15. The method according to claim 14, further comprising:

correcting the measured motor current with a correction value that is obtained in a calibration measurement when the hose line is not inserted into the clamping unit.

16. The device according to claim 14, further comprising:

measuring a path covered by the receiving elements; and

evaluating the motor current as a function of the path covered by the receiving elements.

17. The method according to claim 16, further comprising:

comparing with a preset threshold value at least one of (a) an integral of the motor current and (b) a maximum value of the motor current over a preset path covered by the receiving elements; and

concluding that one of (a) a hose line is inserted into the receiving elements when the threshold value is exceeded, and (b) a specific first hose line is inserted into the receiving elements when the threshold value is exceeded and a specific second hose line is inserted into the receiving elements when the threshold value is fallen below, the first and second hose lines being different hose lines.