Self optimizing lancing device with adaptation means to temporal variations in cutaneous properties

• US 20030233112A1
• Filed: 09/04/2002
• Published: 12/18/2003
• Est. Priority Date: 06/12/2001
• Status: Active Grant

• Current Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Original Assignee: Pelikan Technologies, Inc.
• Inventors: Alden, Don, Freeman, Dominique
• Granted Patent: US 7,316,700 B2
• Time in Patent Office: Days
• US Class Current: 606/181
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/15016 by accessories for bringing the piercing element into the body, e.g. through rotation of the piercing element
• CPC Class Codes: A61B 5/150167 Adjustable piercing speed of skin piercing element, e.g. blade, needle, lancet or canula, for example with varying spring force or pneumatic drive
• CPC Class Codes: A61B 5/150427 Specific tip design, e.g. for improved penetration characteristics
• 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 5/151 Devices specially adapted for taking samples of capillary blood, e.g. by lancets , needles or blades
• CPC Class Codes: A61B 5/15123 comprising magnets or solenoids
• CPC Class Codes: A61B 5/1513 comprising linear sliding guides comprising tooth-shaped elements A61B5/15132

Abstract

Abstract: A lancing device, an embodiment of which controls the advancement and retraction of a lancet by monitoring the position of the lancet in conjunction with a lancet controller which incorporates a feedback loop for modulating the lancet driver to follow a predetermined tissue lancing profile.

Claims

1. A lancing device comprising:

a lancet comprising a shaft having a proximal driving end and a distal lancing end;

a lancet driver coupled to said lancet for longitudinal displacement of said lancet; and

a lancet controller coupled to said lancet driver, said lancet controller comprising a feedback loop for monitoring the longitudinal displacement of said lancet and for modulating the lancet driver to provide a predetermined tissue lancing profile having characteristic phases for lancet advancement and retraction.

2. A lancing device according to claim 1 wherein:

said lancet driver comprises a solenoid.

3. A lancing device according to claim 2 wherein:

said solenoid drives the lancet with electric current.

4. A lancing device according to claim 3 wherein:

said lancet controller comprises additional coil segments disposed adjacent to said solenoid for monitoring the lancet displacement.

5. A lancing device according to claim 1 wherein:

said lancet driver comprises a means for oscillating the lancet to improve the lancet cutting ability.

6. A lancing device according to claim 5 wherein:

said oscillating means comprises a piezoelectric driver.

7. A lancing device according to claim 6 wherein:

said lancet controller controllably varies said tissue lancing profile as a function of impedance changes sensed from said piezoelectric driver resulting from said lancet interacting with said tissue.

8. A lancing device according to claim 5 wherein:

said lancet controller comprises a means for sensing a change in lancing pressure to determine the lancet displacement.

9. A lancing device according to claim 1 wherein:

said lancet controller comprises a processor for modulating the lancet driver.

10. A lancing device according to claim 9 wherein:

said processor comprises memory for storage and retrieval of a set of alternative lancing profiles which the processor uses to modulate the lancet driver.

11. A lancing device according to claim 10 wherein:

a user of said lancing device selects the profile desired from said set of alternative profiles to modulate the lancet.

12. A lancing device according to claim 9 wherein:

said processor optimizes said phases of said tissue lancing profile based on information entered by the user of said lancing device.

13. A lancing device according to claim 9 wherein:

said processor modulates the lancet driver by comparing an actual profile of the lancet to the profile and maintaining a preset error limit between the actual profile and the profile.

14. A lancing device according to claim 9 wherein:

said processor comprises a database for the user.

15. A lancing device according to claim 14 wherein;

said database allows the calculation of statistics for a profile.

16. A lancing device according to claim 9 or 14 wherein:

said processor comprises an internal clock which links the lancing event with a time stamp.

17. A lancing device according to claim 9 wherein:

said processor calculates an appropriate lancet diameter and geometry to collect a blood volume required by the user.

38. A lancing device according to claim 1 wherein:

said feedback loop further comprises a light detecting sensor and a light emitter for monitoring the relative position of said lancet, said lancet further comprising a reflective surface on said proximal end such that said light emitter emits light such that said light is reflected from said reflective surface to said sensor.

39. A lancing device according to claim 1 wherein:

said feedback loop further comprises an electromagnetic sensor for monitoring the relative position of at least one magnetically permeable region disposed on a region of said shaft, said sensor comprising at least one solenoid.

18. A method for lancing tissue comprising the steps of:

selecting a desired profile from a set of alternative profiles having characteristic phases for lancet advancement and retraction;

lancing a user according to said profile;

determining a lancing profile trait during each of said characteristic phases; and

optimizing said profile for subsequent lancing based upon said profile trait as a function of the characteristic phases for lancet advancement and retraction.

19. A method for lancing tissue according to claim 18 wherein:

said profile trait comprises success of obtaining a blood sample from said user.

20. A method for lancing tissue according to claim 18 wherein:

said profile trait comprises blood volume obtained from said user.

21. A method for lancing tissue according to claim 18 wherein:

said profile trait comprises pain perceived by said user.

22. A method for lancing tissue according to claim 18 wherein:

said profile trait comprises a relative time associated with skin deformation.

23. A method for lancing tissue according to claim 18 wherein:

said profile trait comprises dwell time in said tissue of said user.

27. A method for lancing tissue according to claim 18, wherein:

said characteristic phases comprise a completed cycle of advancing and retracting said lancet into and out of a tissue to obtain a blood sample.

28. A method for lancing tissue according to claim 18, wherein:

said characteristic phases further comprising;

a lancet introduction phase comprising a longitudinal advancement of the lancet in a first direction into said tissue;

a lancet rest phase comprising a termination of said longitudinal advancement of said lancet wherein said lancet reaches a maximum depth of tissue penetration and becomes relatively stationary; and

a lancet retraction phase comprising a longitudinal retraction of said lancet in a second direction opposite said first direction out of said tissue.

29. A method for lancing tissue according to claim 28, wherein:

said lancet introduction phase comprises a first time duration; and

said lancet retraction phase comprises a second time duration which is relatively longer than said first time duration.

30. A method for lancing tissue according to claim 28, wherein:

said lancet introduction phase further comprises;

a lancet launch phase comprising a longitudinal advancement of the lancet in said first direction from a stationary loaded lancing position toward the tissue;

a tissue contact phase including a point of initial contact between said distal end of said lancet and the tissue;

a tissue deformation phase comprising deforming said tissue while longitudinally advancing said lancet in said first direction;

a tissue lancing phase comprising penetrating said tissue while longitudinally advancing said lancet in said first direction;

31. A method for lancing tissue according to claim 30, wherein:

said introduction phase varies according to said tissue deformation phase, such that said lancing follows said profile.

32. A method for lancing tissue according to claim 30, wherein:

said introduction phase varies according to said tissue contact phase, such that said lancing follows said profile.

33. A method for lancing tissue according to claim 28, wherein:

said lancet retraction phase further comprises;

a primary lancet retraction phase comprising a longitudinal retraction of the lancet in said second direction from a relatively stationary position during said rest phase where said skin pushes said lancet in said second direction;

a secondary lancet retraction phase comprising a longitudinal retraction of the lancet in said second direction from said position where said skin stops pushing said lancet in said second direction to a position and said lancet is pulled out of said skin in said second direction; and

a lancet exit phase comprising a exit of the lancet from the skin.

34. A method for lancing tissue according to claim 33, wherein:

said retraction phase varies according to said primary retraction phase, such that said lancing follows said profile.

35. A method for lancing tissue according to claim 33, wherein:

said retraction phase varies according to said secondary retraction phase, such that said lancing follows said profile.

24. A method for lancing tissue comprising the steps of:

selecting a desired profile from a set of alternative profiles;

lancing a user according to said profile;

determining whether said lancing generated a blood sample result from said user;

determining whether said lancing had success of obtaining a blood sample from said user;

determining whether said lancing caused pain to said user;

storing said blood sample result, said blood volume, and said pain determinations; and

optimizing said profile for subsequent lancing.

25. A method for lancing tissue according to claim 24 further comprising the step of:

prompting said user to choose between selecting another desired profile and selecting said optimized profile.

26. A method for lancing tissue according to claim 24 further comprising the step of:

selecting a lancet diameter and geometry based on the optimizing of said profile.

36. A lancing device comprising:

means for lancing tissue to obtain a blood sample;

means for driving said lancing means; and

means for controlling said driving means to provide a desired tissue lancing profile.

37. A method for lancing tissue to obtain a blood sample comprising the steps of:

providing a lancet to puncture said tissue;

attaching said lancet to a lancet driver for advancement and retraction of said lancet; and

controlling said lancet advancement and retraction by modulating said lancet driver to vary said advancement and retraction as a function of relative position and motion of said lancet.