LANCING SYSTEM FOR THE EXTRACTION OF A BODY FLUID

• US 20100063417A1
• Filed: 03/03/2009
• Published: 03/11/2010
• Est. Priority Date: 09/04/2006
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: List, Hans, Hoenes, Joachim, Harttig, Herbert, Haar, Hans-Peter, Zimmer, Volker, Kraemer, Uwe, Calasso, Irio G.
• Granted Patent: US 8,444,574 B2
• Time in Patent Office: Days
• US Class Current: 600/583
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150068 by tissue compression, e.g. with specially designed surface of device contacting the skin area to be pierced
• CPC Class Codes: A61B 5/150175 Adjustment of penetration depth
• CPC Class Codes: A61B 5/150389 Hollow piercing elements, e.g. canulas, needles, for piercing the skin
• 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 5/15109 Fully automatically triggered, i.e. the triggering does not require a deliberate action by the user, e.g. by contact with the patient's skin
• CPC Class Codes: A61B 5/15113 Manually triggered, i.e. the triggering requires a deliberate action by the user such as pressing a drive button
• 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 5/15132 comprising tooth-shaped elements, e.g. toothed wheel or rack and pinion

Abstract

Lancing system for extracting a body fluid from the skin of a human or animal comprising a needle element (3) for lancing the skin, a lancing device (2) which includes a lancet drive (15a), by which a lancing movement of the needle element (3) coupled with the lancet drive by means of a coupling mechanism (28) is driven in lancing direction, wherein the lancing device (2) comprises a housing (4) with a housing opening (5) at its in lancing direction front end and the housing opening (5) is surrounded by a housing skin contact surface (7) which is pressed against the skin when using the lancing device (2), the needle element (3) is moved on a predetermined lancing path in a lancing direction in a forward phase of the lancing movement until its tip (3c) enters the skin in order to create a wound and in a return phase of the lancing movement following the reaching of a reversal point corresponding to the lancing depth (S) in the skin is retracted again, a lancing depth reference element (8) with a reference skin contact surface (11) is provided to improve the reproducibility of the lancing depth (S), which is adapted and arranged in such a manner that the reference skin contact surface (11) at the reversal point of the lancing movement is in contact with the skin and the predetermined value of the lancing depth (S) is determined by the distance in lancing direction which prevails at the reversal point of the lancing movement between the reference skin contact surface (11) and the position of the tip (3c) of the needle element (3), at which at the time at which the tip (3c) of the needle element (3) in the forward phase of the lancing movement passes the reference skin contact surface (11) and enters a skin surface which is in contact with said reference skin contact surface, the lancing depth reference element (8) with the reference skin contact surface (11) is in a stationary defined position relative to the reversal point of the lancing movement and the lancing depth reference element (8) is adapted and arranged in such a manner that the skin when pressed against the reference skin contact surface (11) is stabilized with respect to a skin deformation which occurs upon lancing of the skin.

Claims

1. A lancing system for extracting a body fluid from the skin of a human or animal, comprising

a needle element for lancing the skin,

a lancing device, including a lancet drive by which a lancing movement of the needle element is driven in a lancing direction, the needle element being coupled with the lancet drive by means of a coupling mechanism, wherein

the lancing device comprises a housing with a housing opening at its in lancing direction front end and the housing opening is surrounded by a housing skin contact surface which is pressed against the skin during use of the lancing device,

the needle element is, during a forward phase of the lancing movement, moved on a predetermined lancing path in a lancing direction until its tip enters the skin in order to create a wound and is again retracted in a return phase of the lancing movement after having reached a reversal point, the reversal point corresponding to the lancing depth in the skin,

a lancing depth reference element is provided for improving the reproducibility of the lancing depth the lancing depth reference element comprising a reference skin contact surface and being adapted and arranged in such a manner that the reference skin contact surface is, at the reversal point of the lancing movement, in contact with the skin and the predetermined value of the lancing depth is determined by the distance in lancing direction that exists at the reversal point of the lancing movement between the reference skin contact surface and the position of the tip of the needle element,

wherein

at the time at which the tip of the needle element, in the forward phase of the lancing movement, passes the reference skin contact surface and enters a skin surface which is in contact with said reference skin contact surface, the lancing depth reference element with the reference skin contact surface is in a stationary defined position relative to the reversal point of the lancing movement, and the lancing depth reference element is adapted and arranged in such a manner that the skin, on pressing against the reference skin contact surface, is stabilized with respect to a skin deformation occurring when lancing the skin.

2. The lancing system according to claim 1, characterized in that the lancing depth reference element is adapted and arranged in such a manner that during the lancing a skin-stabilizing compressive force acts between the reference skin contact surface and the skin.

3. The lancing system according to claim 2, characterized in that it comprises a force sensor for measuring the compressive force which acts when the skin is pressed against the reference skin contact surface.

4. The lancing system according to claim 2, characterized in that the lancing depth reference element is mounted to be movable opposite to the lancing direction, wherein the force of a spring device acts in the lancing direction against a housing-fixed stop in such a manner that the lancing depth reference element is displaced when the skin is pressed against its reference skin contact surface, the displacement being towards the rear against the force of the spring device and opposite to the lancing direction, wherein the compressive force acting on the skin corresponds to the spring force of the spring device.

5. The lancing system according to claim 1, characterized in that at least a part of the lancing depth reference element, on which the reference skin contact surface is formed, is a disposable element intended for once only use.

6. The lancing system according to claim 1, characterized in that the return phase of the lancing movement includes two part sections wherein the movement of the needle element is faster in the first part section than in the second part section and wherein during the rapid movement of the first part section of the return phase the reference skin contact surface remains in the stationary position.

7. The lancing system according to claim 1, characterized in that during a part of the return phase the lancing depth reference element is moved simultaneously with the needle element.

8. The lancing system according to claim 7, characterized in that the lancing depth reference element and the needle element are moved in synchronization during a part of the return phase in such a manner that the relative distance between the tip of the needle element and the reference skin contact surface of the lancing depth reference element remains unchanged.

9. The lancing system according to claim 1, characterized in that, before the tip of the needle element is completely extracted from the skin, the lancing depth reference element is moved from its stationary position relative to the housing and opposite to the lancing direction only so far that the reference skin contact surface remains in contact with the skin.

10. The lancing system according to claim 1, characterized in that the lancing depth reference element is adapted and arranged in such a manner that it is located in the defined stationary position relative to the housing before the skin is pressed against the housing skin contact surface.

11. The lancing system according to claim 3, characterized in that the lancing device comprises a triggering lock such that the lancing process of the needle element can only be triggered when a predetermined minimum contact pressure is applied between the skin and the reference skin contact surface.

12. The lancing system according to claim 1, characterized in that the lancet drive comprises a drive rotor, the needle element being driven by the rotary movement of the drive rotor.

13. The lancing system according to claim 12, characterized in that the lancet drive comprises a two-part drive rotor, one part being axially displaceable relative to the other part for adjusting the lancing depth of the needle element.

14. The lancing system according to claim 12, characterized in that the lancet drive comprises a tensioning rotor which is coupled with the drive rotor in such a manner that the drive rotor on a part of its movement is moved in synchronization with the tensioning rotor.

15. The lancing system according to claim 14, characterized in that the tensioning rotor comprises a control curve by means of which a traveler is guided the traveler being coupled with the lancing depth reference element via a coupling mechanism.

16. The lancing system according to claim 1, characterized in that the needle element comprises a capillary channel through which a body fluid can be transported out of the skin.

17. The lancing system according to claim 1, characterized in that the lancing device is adapted for multiple use and includes a holder by means of which a lancing unit can be interchangeably coupled with the lancet drive, wherein the reference skin contact surface of the lancing depth reference element is embodied on a disposable single-use element.

18. The lancing system according to claim 1, characterized in that the lancing depth reference element comprises an element opening through which the tip of the needle element extends in the forward phase of the lancing movement and the element opening being arranged such that the smallest distance between the needle element and the reference skin contact surface of the lancing depth reference element measured vertically to the lancing direction, is at most 2 mm, preferentially at most 1 mm and particularly preferably at most 0.5 mm.

19. The lancing system according to claim 18, characterized in that the element opening of the lancing depth reference element is variable in its size.

20. The lancing system according to claim 1, characterized in that the reference skin contact surface is embodied on a plurality of components.

21. The lancing system according to claim 20, characterized in that:

the lancing depth reference element comprises an element opening through which the tip of the needle element extends in the forward phase of the lancing movement and the element opening being arranged such that the smallest distance between the needle element and the reference skin contact surface of the lancing depth reference element measured vertically to the lancing direction, is at most 2 mm, preferentially at most 1 mm and particularly preferably at most 0.5 mm; and

the plurality of components is moveable relative to one another for varying the size of the element opening of the lancing depth reference element.

22. The lancing system according to claim 1, characterized in that it comprises an analysis unit which comprises at least one analysis element for taking up a fluid and for determining an analyte contained in the fluid.

23. The lancing system according to claim 1, characterized in that the lancing depth reference element can be moved in a lateral direction relative to the lancing direction of the lancing movement in such a manner that the housing opening of the lancing device is cleared for allowing the positioning of another function unit of the lancing device, preferably an analytical unit, at the lancing opening to take up a drop of body fluid which emerges there.

24. The lancing system according to claim 23, characterized in that an analysis unit in the lancing device is moveable into a position behind the housing opening.

25. The lancing system according to claim 18, characterized in that:

the element opening of the lancing depth reference element is variable in its size; and

the plurality of components is moveable relative to one another for varying the size of the element opening of the lancing depth reference element.