CONTROL DEVICE FOR A MEDICAL TEST SYSTEM

• US 20120165698A1
• Filed: 02/03/2012
• Published: 06/28/2012
• Est. Priority Date: 08/04/2009
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Inventors: Kuhr, Hans-Juergen, Harttig, Herbert, Haar, Hans-Peter, List, Hans
• Granted Patent: US 9,289,162 B2
• Time in Patent Office: Days
• US Class Current: 600/583
• CPC Class Codes: A61B 5/1411 by percutaneous method, e.g. by lancet
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150175 Adjustment of penetration depth
• CPC Class Codes: A61B 5/150419 comprising means for capillary action
• CPC Class Codes: A61B 5/150435 Specific design of proximal end
• CPC Class Codes: A61B 5/150503 Single-ended needles hollow piercing element tip design A61B5/150396, needle sets for catheters A61M25/06, needles for bringing media into the body A61M5/32
• CPC Class Codes: A61B 5/150946 Means for varying, regulating, indicating or limiting the speed or time of blood collection
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15123 comprising magnets or solenoids
• CPC Class Codes: A61B 5/15128 comprising 2D- or 3D-shaped elements, e.g. cams, curved guide rails or threads comprising tooth-shaped elements A61B5/15132
• CPC Class Codes: A61B 5/1513 comprising linear sliding guides comprising tooth-shaped elements A61B5/15132
• CPC Class Codes: A61B 5/15132 comprising tooth-shaped elements, e.g. toothed wheel or rack and pinion
• CPC Class Codes: A61B 5/15186 Devices loaded with a single lancet, i.e. a single lancet with or without a casing is loaded into a reusable drive device and then discarded after use; drive devices reloadable for multiple use
• CPC Class Codes: A61B 5/1519 comprising driving means, e.g. a spring, for propelling the piercing unit
• CPC Class Codes: A61B 5/15194 fully automatically retracted, i.e. the retraction does not require a deliberate action by the user, e.g. by terminating the contact with the patient's skin
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood

Abstract

The invention concerns a control device for a medical test system which has a lancing element that can be inserted into body tissue to collect body fluid and a lancing drive for the lancing element. A sensor element for body fluid is arranged on the lancing element and a control unit is coupled to the sensor element for detecting a fault when collecting body fluid. In order to improve the success rate, the control unit actuates the lancing drive for an automatic puncture repetition in less than 1 second when a fault, e.g., inadequate wetting of a detection field, occurs.

Claims

1. A medical test system, comprising:

a lancing element that can be inserted into body tissue to collect body fluid;

a lancing drive for the lancing element;

a sensor element for body fluid arranged on the lancing element; and

a control unit coupled to the sensor element for detecting a fault when collecting body fluid;

wherein, in the event of a fault after a first reciprocating lancing movement, the control unit actuates the lancing drive in an automatic second reciprocating lancing movement, the first and second reciprocating lancing movements having a repetition interval of less than 1 second.

2. The medical test system of claim 1, wherein the repetition interval is less than 700 ms.

3. The medical test system of claim 1, wherein the repetition interval is less than 500 ms.

4. The medical test system of claim 1, wherein the sensor element is fluidly connected to a section of a collecting channel for body fluid formed on the lancing element.

5. The medical test system of claim 1, wherein the sensor element generates a control signal that changes discontinuously in reflectance when the sensor element is wetted with body fluid.

6. The medical test system of claim 5, wherein the discontinuous change in reflectance comprises a step-change.

7. The medical test system of claim 1, wherein the sensor element is connected to the control unit by at least one signal conductor during the lancing movement of the lancing element.

8. The medical test system of claim 7, wherein the at least one signal conductor comprises a light guide.

9. The medical test system of claim 1, wherein the sensor element has two or more detection areas arranged spaced apart from one another to detect a two-dimensional load of body fluid.

10. The medical test system of claim 1, wherein the fault comprises the control unit determining an absence of wetting or an inadequate wetting of the sensor element with body fluid.

11. The medical test system of claim 1, further comprising a switch which can be used by a user to deactivate the control unit.

12. The medical test system of claim 1, wherein the control unit has a control loop which automatically adapts lancing parameters for the second lancing movement.

13. The medical test system of claim 1, wherein the lancing drive has an energy store dimensioned for multiple punctures.

14. The medical test system of claim 1, wherein the lancing drive has several energy stores each dimensioned for a single puncture.

15. The medical test system of claim 1, wherein the lancing drive has a brushless direct current motor that can be temporarily subjected to an overcurrent.

16. The medical test system of claim 1, wherein the sensor element has a detection field for a component of the body fluid, and wherein the component as well as the wetting state of the detection field with body fluid can be detected by a unitary measuring unit.

17. The medical test system of claim 1, wherein the lancing element has a collecting volume of less than 100 nl.

18. The medical test system of claim 1, wherein the lancing element has a capillary collecting channel to transfer the body fluid onto the sensor element in a transfer time of less than 0.3 s after skin puncture.

19. A method of using a test system of the type having a lancing element that can be inserted into body tissue to collect body fluid and a lancing drive for driving the lancing element in a reciprocating puncture movement, the method comprising:

driving the lancet in an initial reciprocating puncture movement with the lancing drive;

using a sensor of the lancet to detect body fluid that has been collected with the lancet;

using a control unit that is connected to the sensor to determine whether a fault in collecting body fluid has occurred; and

when a fault is determined by the control unit, driving the lancet in a second reciprocating puncture movement, the initial and second reciprocating puncture movements having a repetition interval of less than 1 second.

20. The method of claim 19, wherein the repetition interval is less than 700 ms.

21. The method of claim 19, wherein the repetition interval is less than 500 ms.

22. The medical test system of claim 19, further comprising generating a control signal that changes discontinuously in reflectance when a detection fields of the sensor is wetted with body fluid.

23. The method of claim 19, further comprising arranging two or more detection fields spaced apart from one another to detect a two-dimensional load of body fluid.

24. The method of claim 19, further comprising, before the second reciprocating puncture, automatically adapting lancing parameters for the second reciprocating puncture.

25. The method of claim 19, wherein the step of determining a fault comprises determining inadequate wetting of a detection field of the sensor.