METHOD FOR CREATING A PUNCTURE WOUND AND HANDHELD APPARATUS SUITABLE THEREFOR

• US 20080208079A1
• Filed: 03/02/2008
• Published: 08/28/2008
• Est. Priority Date: 09/03/2005
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Calasso, Irio, List, Hans, Hein, Heinz-Michael
• Granted Patent: US 8,394,117 B2
• Time in Patent Office: Days
• US Class Current: 600/583
• 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 5/150152 by an adequate mechanical impact on the puncturing location
• 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 5/150427 Specific tip design, e.g. for improved penetration characteristics
• CPC Class Codes: A61B 5/150511 Details of construction of shaft
• CPC Class Codes: A61B 5/15123 comprising magnets or solenoids
• 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
• CPC Class Codes: Y10T 83/0481 Puncturing

Abstract

The invention relates to a method for creating a puncture wound for obtaining a sample of a body fluid from a body part in which a skin opening is created at a puncture site in the epidermis in a skin-opening step. Then, in a sample collection step a sample collection puncture is executed by using a puncture element with which the skin opening is deepened with the puncture element, thereby creating a puncture wound for obtaining the sample. The invention also relates to a handheld apparatus for implementing this method.

Claims

1. A method for creating a puncture wound in the epidermis of a body part to obtain a body fluid sample, comprising:

creating a skin opening in the epidermis at a puncture site to a first depth not reaching blood carrying tissue;

allowing the epidermis at the puncture site to relax; and

inserting a puncture element into the skin opening to a second depth which reaches blood carrying tissue, thereby creating a puncture wound for collecting the sample.

2. The method of claim 1, further comprising waiting from 1 msec to 30 msec between the end of the skin-opening step and the beginning of the inserting step.

3. The method of claim 1, wherein a skin opening element other than the puncture element is used for the skin-opening step.

4. The method of claim 1, wherein the puncture element is used for the skin-opening step, the puncture element being decelerated at the end of the skin-opening step and being accelerated again in the sample collection step.

5. The method of claim 4, wherein the puncture element is stopped at the end of the skin-opening step.

6. The method of claim 5, wherein the puncture element is retracted at the end of the skin-opening step.

7. The method of claim 6, wherein the puncture element is completely withdrawn from the epidermis at the end of the skin-opening step.

8. The method of claim 1, further comprising, before the skin opening step, determining the position of the skin surface relative to a fixed reference point on an apparatus being used to create the puncture wound.

9. The method of claim 8, wherein the step of determining the position of the skin surface comprises an electric measurement.

10. The method of claim 9, wherein the puncture element is used as an electrode and is moved into contact with the skin surface for the electric measurement, and is then retracted into a starting position for the skin-opening step.

11. The method of claim 1, further comprising, after inserting a puncture element into the skin opening to the second depth, retracting the puncture element into a collection position in which the tip of the puncture element remains within the skin.

12. The method of claim 11, further comprising decelerating the puncture element as it approaches the collection position.

13. The method of claim 1, wherein the skin opening created in the skin opening step has a depth of 0.4 mm to 2.0 mm.

14. The method of claim 13, wherein the skin opening created in the skin opening step has a depth of 0.8 mm to 1.2 mm.

15. A method of using a lancing apparatus to create a puncture wound in the epidermis of a body part to obtain a body fluid sample, the lancing apparatus having a puncture element, a drive for reciprocating the puncture element, and a housing having an opening from which the puncture element is accessible for contacting a body part, the method comprising:

(a) contacting the apparatus with a body part from which a body fluid sample is to be obtained;

(b) advancing the puncture element a first distance relative to the apparatus to create a skin opening in the epidermis having a first depth not reaching blood carrying tissue;

(c) allowing the epidermis around the skin opening to relax; and

(d) advancing the puncture element a second distance relative to the apparatus into the skin opening to a second depth which reaches blood carrying tissue, thereby creating a puncture wound for collecting the sample.

16. The method of claim 15, wherein the first distance is substantially the same as the second distance.

17. The method of claim 15, wherein the first distance is less than the second distance.

18. The method of claim 15, further comprising, after step (b), retracting the puncture element.

19. The method of claim 15, further comprising, after step (b), completely withdrawing the puncture element from the body part.

20. The method of claim 15, wherein step (c) comprises a period of from 1 msec to 30 msec.

21. The method of claim 15, further comprising, before step (b), determining the position of the surface of the epidermis relative to a fixed reference point on the apparatus.

22. The method of claim 21, wherein the step of determining the position of the surface comprises an electric measurement.

23. The method of claim 15, further comprising, after step (d), retracting the puncture element into a collection position in which the tip of the puncture element remains within the skin.

24. The method of claim 23, further comprising decelerating the puncture element as it approaches the collection position.

25. The method of claim 15, wherein the skin opening created in step (b) has a depth of 0.4 mm to 2.0 nm.

26. The method of claim 25, wherein the skin opening created in step (b) has a depth of 0.8 mm to 1.2 mm.

27. A handheld apparatus for creating a puncture wound, comprising:

a puncture element;

a drive for moving the puncture element toward and away from the skin;

a control unit for controlling the movement of the puncture element, the control unit being operable to;

move the puncture element in a skin opening step a first distance toward the skin, whereby a skin opening may be created;

slow or pause movement of the puncture element for a time sufficient to allow the epidermis at a puncture site to relax; and

then

move the puncture element toward the skin a second distance, whereby a puncture wound for collecting a sample may be created.

28. The apparatus of claim 27, wherein the control unit is operable to retract the puncture element before the step of moving the puncture element toward the skin the second distance.

29. The apparatus of claim 27, wherein the drive comprises a drive spring for generating a drive force and a drive rotor that is rotatably driven by the drive force, the control unit comprising a curve control linked to the drive rotor, wherein rotational movements of the drive rotor are converted into movements of the puncture element toward and away from the skin.

30. The apparatus of claim 29, wherein the curve control comprises a control curve traveler which travels along a control curve of the drive rotor during a rotational movement of the drive rotor.

31. The apparatus of claim 30, wherein the control curve has a shape comprising a first extremum corresponding to the first depth and a second extremum corresponding to the second depth.

32. The apparatus of claim 30, wherein the control curve comprises an angle of rotation of the drive rotor of at least 360°

.

33. The apparatus of claim 30, wherein relaxing the spring results in a rotational movement of the drive rotor of more than 360°

.

34. The apparatus of claim 30, wherein the control curve is an open control curve.

35. The apparatus of claim 30, wherein, during relaxation of the drive spring, the drive rotor turns in a first direction of rotation and the drive spring is tensioned by the drive rotor when turning in a second direction of rotation, the second direction of rotation being opposite the first direction of rotation.

36. The apparatus of claim 27, further comprising a housing having a housing opening with a pressure ring for contacting to a body part in which a puncture wound is to be created.

37. The apparatus of claim 27, wherein the first distance and the second distance are substantially the same.

38. The apparatus of claim 27, wherein the second distance is greater than the first distance.