U.S. patent application number 10/330724 was filed with the patent office on 2004-07-01 for precision depth control lancing tip.
Invention is credited to Roe, Steven N., Wiegel, Chris.
Application Number | 20040127818 10/330724 |
Document ID | / |
Family ID | 32654574 |
Filed Date | 2004-07-01 |
United States Patent
Application |
20040127818 |
Kind Code |
A1 |
Roe, Steven N. ; et
al. |
July 1, 2004 |
Precision depth control lancing tip
Abstract
A bodily fluid sampling device is operable to lance with a
precise depth and express fluid from both fingertip and alternate
sites. In one form, the device is operable to adjust the
penetration depth of the lancet into the skin. The bodily fluid
sampling device includes a lancet adapted to form an incision in
skin. A skin contacting member has an orifice through which the
lancet extends when lancing the skin. The orifice has a first
opening size that is sized to flatten the skin around the lancet
during lancing. The orifice has a second opening size that is
larger than the first opening size after the incision is formed to
express fluid from the incision.
Inventors: |
Roe, Steven N.; (San Mateo,
CA) ; Wiegel, Chris; (San Jose, CA) |
Correspondence
Address: |
Woodard, Emhardt, Naughton,
Moriarty and McNett LLP
Bank One Center/Tower, Suite 3700
111 Monument Circle
Indianapolis
IN
46204-5137
US
|
Family ID: |
32654574 |
Appl. No.: |
10/330724 |
Filed: |
December 27, 2002 |
Current U.S.
Class: |
600/583 |
Current CPC
Class: |
A61B 5/1519 20130101;
A61B 5/150549 20130101; A61B 5/15194 20130101; A61B 5/150358
20130101; A61B 5/15019 20130101; A61B 5/150442 20130101; A61B
5/150503 20130101; A61B 5/150618 20130101; A61B 5/150068 20130101;
A61B 5/150412 20130101; A61B 5/150022 20130101; A61B 5/150717
20130101 |
Class at
Publication: |
600/583 |
International
Class: |
A61B 005/00 |
Claims
What is claimed is:
1. A bodily fluid sampling device, comprising: an incision forming
member adapted to form an incision in skin; an expression member
defining an expression opening configured to express fluid from the
incision; a reference member defining an aperture through which the
incision forming member extends when forming the incision, the
reference member having a reference surface received in the
expression opening during formation of the incision to contact the
skin and limit penetration depth of the incision forming member
into the skin; and a retraction mechanism coupled to the reference
member to retract the reference surface from the expression
opening.
2. The device of claim 1, wherein said retraction mechanism
includes a spring coupled between the expression member and the
reference member to bias the reference surface out of the
expression opening after the incision is formed.
3. The device of claim 1, wherein said retraction mechanism
includes: a housing connected to the expression member; a sleeve
slidably received around the housing; and a cam arm pivotally
coupled to the housing, the cam arm engaging the sleeve and the
reference member to retract the reference surface of the reference
member from the expression opening when the sleeve slides towards
the skin.
4. The device of claim 3, wherein the retraction mechanism includes
a second cam arm pivotally coupled to the housing, the second cam
arm engaging the sleeve and the reference member to retract the
reference surface of the reference member from the expression
opening when the sleeve slides towards the skin.
5. The device of claim 3, further comprising a spring positioned
between the housing and the sleeve to bias the reference surface
into the expression opening.
6. The device of claim 5, further comprising a nut coupled to the
sleeve and engaging the spring.
7. The device of claim 3, further comprising a lock mechanism to
lock the reference member in a retracted position in which the
reference surface is retracted from the expression opening.
8. The device of claim 7, wherein the lock mechanism includes: a
latch coupled to the sleeve; and a lock tab extending from the cam
arm that is engageable with the latch.
9. The device of claim 1, further comprising a lock mechanism to
lock the reference member in a retracted position in which the
reference surface is retracted from the expression opening.
10. The device of claim 1, wherein the reference member is coupled
to the incision forming member to adjust the penetration depth of
the incision forming member.
11. The device of claim 10, wherein: the incision forming member
has threads; and the reference member has threads engageable with
the threads of the incision forming member for adjusting the
penetration depth of the incision forming member.
12. The device of claim 1, further comprising a penetration depth
adjustment mechanism to adjust the penetration depth of the
incision forming member.
13. The device of claim 12, wherein the penetration depth
adjustment mechanism includes an adjuster having a stop surface
engageable with the incision forming member to limit the
penetration depth of the incision forming member, the adjuster
threadedly engaging the reference member for adjusting a distance
between the reference surface and the stop surface of the
adjuster.
14. The device of claim 12, wherein the penetration depth
adjustment mechanism includes the reference member threadedly
engaged with the incision forming member for adjusting the
penetration depth of the incision forming member.
15. A bodily fluid sampling device, comprising: a skin lancing
member adapted to form an incision in skin; and a skin contacting
member having an orifice through which the skin lancing member
extends to form the incision, the orifice having a first opening
size that is sized to flatten the skin around the skin lancing
member while the skin lancing member forms the incision and a
second opening size that is larger than the first opening size
after the incision is formed to express fluid from the
incision.
16. The device of claim 15, wherein the skin contacting member
includes: a reference member defining an aperture having the first
opening size; and an expression member defining an expression
opening having the second opening size.
17. The device of claim 16, wherein: at least a portion of the
reference member is positioned in the expression opening during
formation of the incision; and the skin contacting member includes
a retraction mechanism to retract the reference member from the
expression opening after the incision is formed.
18. The device of claim 17, wherein said retraction mechanism
includes a spring coupled between the expression member and the
reference member to bias the reference surface out of the
expression opening after the incision is formed.
19. The device of claim 17, wherein said retraction mechanism
includes: a housing connected to the expression member; a sleeve
slidably received around the housing; and a cam arm pivotally
coupled to the housing, the cam arm engaging the sleeve and the
reference member to retract the reference surface of the reference
member from the expression opening when the sleeve slid towards the
skin.
20. The device of claim 19, wherein the retraction mechanism
includes a second cam arm pivotally coupled to the housing, the
second cam arm engaging the sleeve and the reference member.
21. The device of claim 19, further comprising a spring positioned
between the housing and the sleeve to bias the reference surface
into the expression opening.
22. The device of claim 15, wherein the skin contacting member
includes: a cover defining an aperture having the first opening
size; and a plurality of living hinges extending around the
aperture to support the cover, the living hinges being bendable to
form an expression opening having the second opening size.
23. The device of claim 22, further comprising an opening size
adjustment mechanism.
24. The device of claim 22, wherein: the opening size adjustment
mechanism includes an outer tube defining a guide slot, and an
inner tube received in the outer tube, the inner tube having a
guide member received in the guide slot; said living hinges are
connected between the inner tube and the outer tube; and said guide
slot is configured to retract a portion of the inner tube inside
the outer tube to bend the living hinges and form the expression
opening having the second opening size.
25. A bodily fluid sampling device, comprising: an incision forming
member operable to form an incision in skin; a reference member
having a reference surface positioned proximal the incision forming
member to engage the skin around the incision forming member during
formation of the incision; and means for adjusting penetration
depth of the incision forming member into the skin.
26. The device of claim 25, wherein the means for adjusting the
penetration depth includes an adjuster having a stop surface
engageable with the incision forming member to limit the
penetration depth of the incision forming member, the adjuster
threadedly engaging the reference member for adjusting a distance
between the reference surface and the stop surface of the
adjuster.
27. The device of claim 25, wherein the means for adjusting the
penetration depth includes the reference member threadedly engaging
with the incision forming member.
28. The device of claim 25, further comprising: a head portion
attached to the incision forming member; a leaf spring attached to
the head; wherein the reference member includes a cover attached to
the leaf spring; and wherein the means for adjusting the
penetration depth includes wheel having a series of steps with
different thicknesses positioned between the head and the
cover.
29. The device of claim 25, wherein: the reference member includes
a living hinge connected to the incision forming member and a stop
flange; the means for adjusting the penetration depth includes a
holder holding the incision forming member, a depth control member
threadedly engaged with the holder and positioned to contact the
stop flange to limit the penetration depth.
30. A method, comprising: forming an incision in the skin with a
lancing member of a sampling device through an aperture in the
device that has a first opening size; configuring the aperture to a
second opening size that is larger than the first opening size; and
expressing fluid from the incision with the aperture at the second
opening size.
31. The method of claim 30, wherein: the device includes a
reference member that defines a lancing opening at the first
opening size received inside an expression opening at the second
opening size defined in an expression member; and said configuring
includes retracting the reference member from the expression
opening.
32. The method of claim 30, wherein: the device includes a cover
that define a lancing opening with the first opening size and a
plurality of living hinges extending around the lancing opening to
support the cover; said configuring includes deforming the living
hinges to create an expression opening having the second opening
size.
33. A device for sampling a bodily fluid from an incision in a
user's skin, comprising: an expression member including a first,
skin-contacting surface defining a first opening; a depth-control
member including a second, skin-contacting surface defining a
second opening smaller than the first opening, said depth-control
member being movable between first and second positions relative to
said expression member, said depth-control member in the first
position being retracted relative to said expression member to be
displaced from skin received in the first opening of said
expression member, said depth-control member in the second position
being positioned relative to said expression member to contact skin
received in the first opening of said expression member; and an
incision forming member extendable through the second opening of
said depth-control member in the second, skin-contacting
position.
34. The device of claim 33 in which said expression member and said
depth-control member comprise concentric, annular-shaped
skin-contacting surfaces.
35. The device of claim 33 and which further includes means for
adjusting the position of the incision forming member relative to
said depth-control member to control the depth of penetration of
the incision forming member into the user's skin.
36. The device of claim 35 in which said incision forming member is
connected with and movable relative to said depth-control
member.
37. The device of claim 36 in which said incision forming member
includes a lancet extending beyond the skin-contacting surface of
said depth-control member.
38. A device for sampling a bodily fluid from an incision in a
user's skin, comprising: a skin-contacting member including an end
portion configurable between two positions, said skin-contacting
member in the first position defining a first skin-contacting
surface including a depth-control opening, said skin-contacting
member in the second position defining a second skin-contacting
surface including an expression opening larger than the
depth-control opening; and an incision forming member extendable
through the depth-control opening of said skin-contacting
member.
39. A method for sampling a bodily fluid from an incision in a
user's skin, comprising: providing a sampling device including an
expression member including a first, skin-contacting surface
defining a first opening, a depth-control member including a
second, skin-contacting surface defining a second opening smaller
than the first opening, the depth-control member being movable
between first and second positions relative to the expression
member, the depth-control member in the first position being
retracted relative to the expression member to be displaced from
skin received in the first opening of the expression member, the
depth-control member in the second position being positioned
relative to the expression member to contact skin received in the
first opening of the expression member, and an incision forming
member extendable through the second opening of the depth-control
member in the second, skin-contacting position placing the sampling
device against the user's skin to engage the skin against the
skin-contacting surface of the expression member; positioning the
depth-control member in the second position to engage the user's
skin; advancing the incision forming member relative to the
expression member to incise the skin to produce a bodily fluid from
the incision; and withdrawing the depth-control member to the first
position displaced from the user's skin.
40. The method of claim 39 in which the incision forming member is
connected with the depth-control member and said positioning of the
depth-control member to engage the skin and said advancing the
incision forming member to incise the skin are performed
simultaneously.
41. The method of claim 39 and which further includes, after said
advancing, withdrawing the incision forming member from the
skin.
42. The method of claim 41 in which the incision forming member is
connected with the depth-control member and said withdrawing of the
depth-control member and said withdrawing of the incision forming
member are performed simultaneously.
43. The method of claim 39 and which further includes sampling the
bodily fluid while maintaining engagement between the
skin-contacting surface of the expression member and the skin.
44. A method for sampling a bodily fluid from an incision in a
user's skin, comprising: providing a sampling device comprising a
skin-contacting member including an end portion configurable
between two positions, the skin-contacting member in the first
position defining a first skin-contacting surface including a
depth-control opening, the skin-contacting member in the second
position defining a second skin-contacting surface including an
expression opening larger than the depth-control opening, and an
incision forming member extendable through the depth-control
opening of the skin-contacting member placing the sampling device
against the user's skin with the skin-contacting member in the
first, depth-control position to engage the skin against the
skin-contacting surface and received within the depth-control
opening; advancing the incision forming member through the
depth-control opening to incise the skin; withdrawing the incision
forming member from the depth-control opening to be displaced from
the user's skin; and reconfiguring the end portion of the
skin-contacting member to the second position while maintaining
contact between the skin-contacting member and the skin to receive
the skin within the expression opening.
45. The method of claim 44 and which further includes sampling the
bodily fluid while maintaining engagement between the
skin-contacting surface of the expression member and the skin.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention generally relates to bodily fluid
sampling devices and more specifically, but not exclusively,
concerns a bodily fluid sampling device configured to form an
incision having a precise depth and express fluid from both finger
and alternate site testing (AST) locations.
[0002] General Fluid Testing
[0003] The acquisition and testing of bodily fluids is useful for
many purposes, and continues to grow in importance for use in
medical diagnosis and treatment, and in other diverse applications.
In the medical field, it is desirable for lay operators to perform
tests routinely, quickly and reproducibly outside of a laboratory
setting, with rapid results and a readout of the resulting test
information. Testing can be performed on various bodily fluids, and
for certain applications is particularly related to the testing of
blood and/or interstitial fluid. Such fluids can be tested for a
variety of characteristics of the fluid, or analytes contained in
the fluid, in order to identify a medical condition, determine
therapeutic responses, assess the progress of treatment, and the
like.
[0004] General Test Steps
[0005] The testing of bodily fluids basically involves the steps of
obtaining the fluid sample, transferring the sample to a test
device, conducting a test on the fluid sample, and displaying the
results. These steps are generally performed by a plurality of
separate instruments or devices.
[0006] Acquiring--Vascular
[0007] One method of acquiring the fluid sample involves inserting
a hollow needle or syringe into a vein or artery in order to
withdraw a blood sample. However, such direct vascular blood
sampling can have several limitations, including pain, infection,
and hematoma and other bleeding complications. In addition, direct
vascular blood sampling is not suitable for repeating on a routine
basis, can be extremely difficult and is not advised for patients
to perform on themselves.
[0008] Acquiring--Incising
[0009] The other common technique for collecting a bodily fluid
sample is to form an incision in the skin to bring the fluid to the
skin surface. A lancet, knife or other cutting instrument is used
to form the incision in the skin. The resulting blood or
interstitial fluid specimen is then collected in a small tube or
other container, or is placed directly in contact with a test
strip. The fingertip is frequently used as the fluid source because
it is highly vascularized and therefore produces a good quantity of
blood. However, the fingertip also has a large concentration of
nerve endings, and lancing the fingertip can therefore be painful.
Alternate sampling sites, such as the palm of the hand, forearm,
earlobe and the like, may be useful for sampling, and are less
painful. However, they also produce lesser amounts of blood. These
alternate sites therefore are generally appropriate for use only
for test systems requiring relatively small amounts of fluid, or if
steps are taken to facilitate the expression of the bodily fluid
from the incision site.
[0010] Various methods and systems for incising the skin are known
in the art. Exemplary lancing devices are shown, for example, in
U.S. Re. Pat. No. 35,803, issued to Lange, et al. on May 19, 1998;
U.S. Pat. No. 4,924,879, issued to O'Brien on May 15, 1990; U.S.
Pat. No. 5,879,311, issued to Duchon et al. on Feb. 16, 1999; U.S.
Pat. No. 5,857,983, issued to Douglas on Jan. 12, 1999; U.S. Pat.
No. 6,183,489, issued to Douglas et al. on Feb. 6, 2001; U.S. Pat.
No. 6,332,871, issued to Douglas et al. on Dec. 25, 2001; and U.S.
Pat. No. 5,964,718, issued to Duchon et al. on Oct. 12, 1999. A
representative commercial lancing device is the Accu-Chek Softclix
lancet.
[0011] Expressing
[0012] Patients are frequently advised to urge fluid to the
incision site, such as by applying pressure to the area surrounding
the incision to milk or pump the fluid from the incision.
Mechanical devices are also known to facilitate the expression of
bodily fluid from an incision. Such devices are shown, for example,
in U.S. Pat. No. 5,879,311, issued to Duchon et al. on Feb. 16,
1999; U.S. Pat. No. 5,857,983, issued to Douglas on Jan. 12, 1999;
U.S. Pat. No. 6,183,489, issued to Douglas et al. on Feb. 6, 2001;
U.S. Pat. No. 5,951,492, issued to Douglas et al. on Sep. 14, 1999;
U.S. Pat. No. 5,951,493, issued to Douglas et al. on Sep. 14, 1999;
U.S. Pat. No. 5,964,718, issued to Duchon et al. on Oct. 12, 1999;
and U.S. Pat. No. 6,086,545, issued to Roe et al. on Jul. 11, 2000.
A representative commercial product that promotes the expression of
bodily fluid from an incision is the Amira AtLast blood glucose
system.
[0013] Sampling
[0014] The acquisition of the produced bodily fluid, hereafter
referred to as the "sampling" of the fluid, can take various forms.
Once the fluid specimen comes to the skin surface at the incision,
a sampling device is placed into contact with the fluid. Such
devices may include, for example, systems in which a tube or test
strip is either located adjacent the incision site prior to forming
the incision, or is moved to the incision site shortly after the
incision has been formed. A sampling tube may acquire the fluid by
suction or by capillary action. Such sampling systems may include,
for example, the systems shown in U.S. Pat. No. 6,048,352, issued
to Douglas et al. on Apr. 11, 2000; U.S. Pat. No. 6,099,484, issued
to Douglas et al. on Aug. 8, 2000; and U.S. Pat. No. 6,332,871,
issued to Douglas et al. on Dec. 25, 2001. Examples of commercial
sampling devices include the Roche Compact, Amira AtLast,
Glucometer Elite and Therasense FreeStyle test strips.
[0015] Testing General
[0016] The bodily fluid sample may be analyzed for a variety of
properties or components, as is well known in the art. For example,
such analysis may be directed to hematocrit, blood glucose,
coagulation, lead, iron, etc. Testing systems include such means as
optical (e.g., reflectance, absorption, fluorescence, Raman, etc.),
electrochemical, and magnetic means for analyzing the sampled
fluid. Examples of such test systems include those in U.S. Pat. No.
5,824,491, issued to Priest et al. on Oct. 20, 1998; U.S. Pat. No.
5,962,215, issued to Douglas et al. on Oct. 5, 1999; and U.S. Pat.
No. 5,776,719, issued to Douglas et al. on Jul. 7, 1998.
[0017] Typically, a test system takes advantage of a reaction
between the bodily fluid to be tested and a reagent present in the
test system. For example, an optical test strip will generally rely
upon a color change, i.e., a change in the wavelength absorbed or
reflected by dye formed by the reagent system used. See, e.g., U.S.
Pat. Nos. 3,802,842; 4,061,468; and U.S. Pat. No. 4,490,465.
[0018] Blood Glucose
[0019] A common medical test is the measurement of blood glucose
level. The glucose level can be determined directly by analysis of
the blood, or indirectly by analysis of other fluids such as
interstitial fluid. Diabetics are generally instructed to measure
their blood glucose level several times a day, depending on the
nature and severity of their diabetes. Based upon the observed
pattern in the measured glucose levels, the patient and physician
determine the appropriate level of insulin to be administered, also
taking into account such issues as diet, exercise and other
factors.
[0020] In testing for the presence of an analyte such as glucose in
a bodily fluid, test systems are commonly used which take advantage
of an oxidation/reduction reaction which occurs using an
oxidase/peroxidase detection chemistry. The test reagent is exposed
to a sample of the bodily fluid for a suitable period of time, and
there is a color change if the analyte (glucose) is present.
Typically, the intensity of this change is proportional to the
concentration of analyte in the sample. The color of the reagent is
then compared to a known standard which enables one to determine
the amount of analyte present in the sample. This determination can
be made, for example, by a visual check or by an instrument, such
as a reflectance spectrophotometer at a selected wavelength, or a
blood glucose meter. Electrochemical and other systems are also
well known for testing bodily fluids for properties on
constituents.
[0021] Alternate Site Testing (AST)
[0022] As mentioned above, the fingertip is frequently used as the
fluid source because it is highly vascularized and therefore
produces a good quantity of blood. However, the fingertip also has
a large concentration of nerve endings, and lancing the fingertip
can therefore be painful. Alternate sampling sites, such as the
palm of the hand, forearm, earlobe and the like, may be useful for
sampling, and are less painful. However, they also produce less
blood when lanced.
[0023] In general, bodily fluid sampling devices are designed to
express blood from either the fingertip or an alternate site, but
not both. Typically, alternate site sampling devices need to
express fluid from a large surface area surrounding the site in
order to draw a sufficient amount of fluid for testing.
Furthermore, it is usually more desirable to lance the skin deeply
at the alternate site in order to ensure that a sufficient amount
of fluid can be expressed. In comparison, fingertips are relatively
small and do not need to be deeply lanced or require a large area
in order to express a sufficient amount of fluid. Therefore,
alternate site sampling devices usually have larger openings for
expressing fluid as compared to devices designed to express fluid
from fingers. If an alternate site sampling device were used to
lance and express fluid from a fingertip, severe pain or serious
injury to the finger may result. With the alternate site device,
when an incision is being formed in the fingertip, the skin can
tend to deform or bulge into the expression opening such that the
lancet forms an incision with a greater depth than needed.
[0024] Thus, needs remain for further contributions in this area of
technology.
SUMMARY OF THE INVENTION
[0025] One form of the present invention concerns a bodily fluid
sampling device that includes an incision forming member adapted to
form an incision in skin. An expression member defines an
expression opening configured to express fluid from the incision. A
reference member defines an aperture through which the incision
forming member extends when forming the incision. The reference
member has a reference surface received in the expression opening
during formation of the incision to contact the skin and limit
penetration depth of the incision forming member into the skin. A
retraction mechanism is coupled to the reference member to retract
the reference surface from the expression opening.
[0026] Further forms, objects, features, aspects, benefits,
advantages, and embodiments of the present invention will become
apparent from a detailed description and drawings provided
herewith.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a cross-sectional view of a bodily fluid sampling
device according to one embodiment of the present invention.
[0028] FIG. 2 is a cross-sectional view of the FIG. 1 device during
lancing at an alternate site.
[0029] FIG. 3 is a cross-sectional view of the FIG. 1 device
expressing fluid from the alternate site.
[0030] FIG. 4 is a cross-sectional view of the FIG. 1 device
configured to lance from a fingertip site.
[0031] FIG. 5 is a cross-sectional view of the FIG. 1 device
lancing the fingertip site.
[0032] FIG. 6 is a cross-sectional view of a bodily fluid sampling
device according to according to another embodiment.
[0033] FIG. 7 is a cross-sectional view of the FIG. 6 device
configured to express fluid from an alternate site.
[0034] FIG. 8 is an exploded view of the FIG. 6 device.
[0035] FIG. 9 is a perspective view of the FIG. 6 device.
[0036] FIG. 10 is a perspective view of a lancing device according
to a further embodiment of the present invention.
[0037] FIG. 11 is a cross-sectional view of the FIG. 10 device.
[0038] FIG. 12 is a perspective view of the FIG. 10 device
configured for a deep penetration depth.
[0039] FIG. 13 is a perspective view of the FIG. 10 device
configured for a shallow penetration depth.
[0040] FIG. 14 is a cross-sectional view of a lancing device
according to another embodiment.
[0041] FIG. 15 is an exploded view of a sampling device according
to a further embodiment.
[0042] FIG. 16 is a perspective view of the FIG. 15 device.
[0043] FIG. 17 is a perspective view of the FIG. 16 in an armed
configuration.
[0044] FIG. 18 is a perspective view of a sampling device according
to another embodiment.
[0045] FIG. 19 is a top perspective view of the FIG. 18 device in a
lancing position.
[0046] FIG. 20 is a bottom perspective view of the FIG. 18 device
in a lancing position.
[0047] FIG. 21A is a top perspective view of a sampling device
according to a further embodiment.
[0048] FIG. 21B is a bottom perspective view of the FIG. 21A
device.
[0049] FIG. 22 is a perspective view of an adjustable holder
according to another embodiment holding the FIG. 21A device.
[0050] FIG. 23 is an exploded view of a sampling device according
to another embodiment.
[0051] FIG. 24 is a perspective view of the FIG. 23 device.
[0052] FIG. 25 is a front view of the FIG. 23 device.
[0053] FIG. 26 is a side view of the FIG. 23 device.
[0054] FIG. 27 is a cross-sectional view of the FIG. 23 device
configured to express fluid from a fingertip.
[0055] FIG. 28 is a cross-sectional view of the FIG. 23 device
configured to express fluid from an alternate site.
[0056] FIG. 29 a front view of a sampling device according to a
further embodiment.
[0057] FIG. 30 is a cross-sectional view of the FIG. 29 device
configured to express fluid from a fingertip.
[0058] FIG. 31 is a cross-sectional view of the FIG. 29 device
configured to express fluid from an alternate site.
DESCRIPTION OF THE SELECTED EMBODIMENTS
[0059] For the purposes of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiments illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended, such alterations and further modifications in the
illustrated device, and such further applications of the principles
of the invention as illustrated therein being contemplated as would
normally occur to one skilled in the art to which the invention
relates. One embodiment of the invention is shown in great detail,
although it will be apparent to those skilled in the relevant art
that some features that are not relevant to the present invention
may not be shown for the sake of clarity.
[0060] Bodily fluid sampling devices according to the present
invention are operable to form an incision with a precise depth and
express fluid from both fingertip and alternate sites. The devices
can further be configured to allow for the adjustment of the
penetration depth of the lancet. In one particular embodiment, the
device includes a reference member that provides a reference
surface for controlling the penetration depth of a lancet. The
reference member is received in a large expression opening of an
expression member. During lancing, the reference member flattens
the skin in the expression opening such that an incision with a
precise depth can be formed. After lancing the skin, the reference
member can be retracted from the expression opening so that the
larger expression opening can be used to express a sufficient
amount of bodily fluid from the alternate site. In one form, a
spring automatically retracts the reference member after lancing,
and in other forms, cam mechanisms are used to retract the
reference member during expression of the fluid. In other
embodiments, the reference member is coupled to the lancet in order
to control the penetration depth of the lancet. Further aspects of
the present concern integrated sampling devices that allow test
media to be attached to the lancet after sterilization so as to
ensure that the test media remains properly calibrated.
[0061] A bodily fluid sampling device 40 according to one
embodiment of the present invention is illustrated in FIGS. 1-5.
Referring to FIG. 1, the sampling device 40 includes an incision
forming member 42, a penetration depth adjuster 44, an expression
member 46, and a reference member 48. For the sake of clarity and
brevity, other components of the sampling device 40 that are well
know in the art, such has hammers, cocking mechanisms and the like
that are not important to appreciate the present invention, will
not be discussed below. For examples of such components, please
refer to U.S. Pat. No. 5,964,718, issued to Duchon et al. on Oct.
12, 1999, which is hereby incorporated by reference in its
entirety. The device 40 illustrated in FIG. 1 can be back loaded
into a sampling device of the type described in U.S. Pat. No.
5,964,718.
[0062] As shown in FIG. 1, the incision forming member 42 has a
lancet 50 that is attached to a lancet body 52. In the illustrated
embodiment, the lancet 50 is in the form of a needle. However, it
should be appreciated that the lancet 50 can come in other forms,
such as a blade. Moreover, although a single lancet is shown, the
incision forming member 42 in other embodiments can include
multiple lancets 50. As depicted in FIG. 1, the lancet body 52 has
a depth stop surface 54, which is used to control the penetration
depth of the lancet 50. The lancet 50 further includes a flange 56
positioned proximal to tip 58 of the lancet 52, which is configured
to cut the skin S. In one form of the present invention, the flange
56 can be used as an auxiliary stop in order to prevent over
penetration of the lancet 52 into the skin S.
[0063] With continued reference to FIG. 1, the sampling device 40
has a depth control assembly 59 that is able to adjust the
penetration depth of the lancet 52. The depth control assembly 58
includes adjuster 44 and reference member 48. As depicted, the
adjuster 44 has an outer adjustment member 60 attached to an inner
adjustment member 62 that interfaces with the reference member 48.
The outer expression member 46 defines a slot 64 through which arm
66 of the adjuster 44 connects the outer adjustment member 60 to
the inner adjustment member 62. The outer adjustment member 60 in
the illustrated embodiment is in the form of a ring that encircles
the outer expression member 46. To adjust the penetration depth of
the lancet 50, the user rotates the outer adjustment member 60
around the device 40. The inner adjustment member 62 further
incorporates an outwardly extending flange 68 that engages an
inwardly extending flange 70 in the outer expression member 46. As
shown in FIG. 1, the inner adjustment member 62 defines an inner
passageway 72 through which the lancet 50 extends. Inside
passageway 72, the inner adjustment member 62 has a stop flange 74
that is configured to engage the stop surface 54 on the incision
forming member 42.
[0064] As depicted, the inner adjustment member 62 has at least one
thread 76 that engages a corresponding groove 78 formed in the
reference member 48. As should be appreciated, in other
embodiments, the reference member 48 can be threaded and the inner
adjustment member 62 can have corresponding grooves. Although the
reference member 48 surrounds the inner adjustment member 62 in the
illustrated embodiment, at least a portion of the reference member
48 in other embodiments can be received inside the inner adjustment
member 62. To prevent the reference member 48 from rotating with
the adjuster 44 when the penetration depth is adjusted, the outer
expression member 46 has a slot 80 that engages the reference
member 48.
[0065] Referring to FIG. 1, the reference member 48 has a contact
portion 82 that is adapted to extend through expression opening 84
that is defined in the expression member 46. The contact portion 82
has a skin contacting surface 86 that contacts the skin S when the
incision is formed by the lancet 50. Surface 86 surrounds an
aperture 88 through which tip 58 of the lancet 50 extends. Distance
D1 between the skin contacting surface 86 and stop surface 89 on
the stop flange 74 of the adjuster 44 controls the penetration
depth of the lancet 50. Rotating the outer adjustment member 60
changes distance D1, thereby changing the penetration depth of the
lancet 50.
[0066] Extending around opening 84 in the outer expression member
46 is a ridge 90 that is adapted to engage the reference member 48
so as to control how far the contact portion 82 extends from the
expression member 46. The outer expression member 46 further has an
expression surface 92 that is angled or inclined towards opening 84
in order to promote expression of bodily fluid. In one form, the
expression surface 92 has a generally frusto-conical shape. An
opening size adjustment or retraction mechanism 93 is used to
retract reference member 48 from the expression opening 84 so as to
change the opening size for expressing fluid. In the illustrated
embodiment, mechanism 93 includes a spring 94. As will be
appreciated from the discussion below concerning the other
embodiments, other types of size adjustment mechanisms 93 can be
used to change the size of the opening for expressing fluid. Spring
94, which is positioned between the outer expression member 46 and
the reference member 48, biases the reference member 48 along with
the adjuster 44 against flange 70 so that the contact portion 82 is
positioned out of the expression opening 84.
[0067] As mentioned above, alternate sampling sites A, such as the
palm of the hand, forearm, earlobe and the like, may be useful for
sampling because lancing these sites tends to be less painful.
However, one drawback with the alternate site A is that the amount
of fluid that can be expressed from an incision formed in that area
is relatively small when compared to fingertip sites. One solution
has been to increase the opening size in an expression ring so as
to increase the area in which fluid is expressed from the skin.
However, due to the larger opening size, the skin tends to bulge to
a greater degree, thereby increasing the penetration depth of the
lancet by a variable amount when the incision is formed at the
alternate site A. In device 40, the expression opening 84 is sized
to express a sufficient amount of fluid for testing from the
alternate site A. In comparison to the expression opening 84, the
aperture 88 in the reference member 48 is relatively small. In one
embodiment, the aperture 88 is sized to be slightly larger than the
lancet tip 58 such that the lancet 50 is able to slide through the
aperture 88. The size of the reference member 48 minimizes skin
deformation around the lancet 50 when piercing the skin S, thereby
ensuring the device 40 forms incisions with substantially
consistent depths.
[0068] During lancing, as shown in FIG. 2, the incision forming
member 42 is actuated to move towards the skin S. As should be
understood, the incision forming member 42 can be driven towards
the skin S through a number of mechanisms, such as for example by a
hammer striking the incision forming member 42. As the incision
forming member 42 moves toward the skin S, the stop surface 54 of
the incision forming member 42 contacts the inner flange 74 of the
adjuster 44 such that the reference member 48 is driven toward the
skin S. While the adjuster 44 and the reference member 48 are
driven towards the skin S, the arm 66 of the adjuster 44 slides
within the slot 64 of the outer expression member 46. In FIG. 2,
the contact portion 84 of the reference member 82 extends through
the expression opening 84 such that the skin contacting surface 86
of the reference member 48 contacts and flattens the skin S
surrounding the lancet 50 as incision I is formed. As previously
discussed, the distance D1 between the skin contacting surface 86
and the stop surface 89 of the stop flange 74 controls the
penetration depth P1 of the lancet 50 in to the skin S.
[0069] Referring to FIG. 3, after the incision I is formed in the
skin S, the spring 94 retracts the reference member 48 from the
expression opening 84. The user is able to express bodily fluid B
from the incision I using the larger expression opening 84. As
should be appreciated from the discussion above, this design allows
a greater amount of fluid to be expressed from an alternate site A,
while at the same time forms an incision having precise depth.
[0070] As discussed above, the penetration depth of the lancet 50
can be adjusted by rotating the outer adjustment member 60 of the
adjuster 44. As illustrated in FIG. 4, rotating the outer
adjustment member 60 of the adjuster 44 extends the reference
member 48 from the adjuster 44, thereby increasing distance D2
between the skin contacting surface 86 of the reference member 48
and the flange 74 of the adjuster 44. Increasing distance D2 in
turn reduces the penetration depth P2 of the lancet 50, as is
illustrated in FIG. 5. Reducing the penetration depth P2 can help
reduce the pain associated with lancing at especially sensitive
sites, such as fingertip site F.
[0071] A bodily fluid sampling device 40a according to another
embodiment of the present invention will now be described with
reference to FIGS. 6-9. The sampling device 40a of the illustrated
embodiment is configured to automatically increase the size of the
expression opening when fluid is expressed from an alternate site.
As illustrated in FIGS. 6 and 8, the sampling device 40a includes a
sleeve 96 that encloses incision forming member 42, which has
lancet 50 and lancet body 52, of the type described above. In the
illustrated embodiment, surface 54 of the lancet body 52 does not
act as an end stop for controlling the penetration depth of the
lancet 50. Rather, a fixed stop inside the mechanism that is used
to actuate the lancet 50 controls the penetration depth. For
instance, device 40a can be incorporated into a SOFTCLIX brand
lancing device (Boehringer Mannheim GmbH Corporation, Germany) in
order to actuate and control the penetration depth of the lancet
50. It is contemplated, however, that device 40a can be modified
such that surface 54 of the lancet body 52 can act as a stop
surface for controlling the penetration depth of the lancet 50. In
FIG. 6, the sleeve 96 is slidable over a lancet housing 98. As
shown, the lancet housing 98 encloses the incision forming member
42. A spring 100 is operatively positioned between the sleeve 96
and the housing 98 for biasing the sleeve 96. In FIGS. 6 and 8, the
sleeve 96 is attached to a nut or inner flange 102 against which
the spring 100 engages, and in a similar fashion, the housing 98
has an outwardly extending flange 104 that engages the spring 100.
In one form, the nut 102 threadedly engages the sleeve 96, and in
another embodiment, the nut 102 is integrally formed with the
sleeve 96. As should be understood, nut 102 and flange 104 can be
attached in other manners. The sleeve 96 further includes one or
more guide arms 106 that longitudinally extend from the sleeve 96.
In the illustrated embodiment, the sleeve 96 has a pair of guide
arms 106. However, it should be appreciated that the sleeve 96 can
have a different number of guide arms 106 in other embodiments.
Each guide arm 106 has an end stop member 107 that extends in an
inward radial direction so as to engage flange 104 of the housing
98. The sleeve 96 further has an outer collar 108 that assists the
user in gripping the sleeve 96. To prevent rotation of the housing
98 relative to the sleeve 96, the housing 98 has guide ridges 109
that longitudinally extend on opposite sides of the guide arms 106,
as shown in FIG. 8.
[0072] Similar to the above described embodiment, the sampling
device 40a illustrated in FIGS. 6-9 includes an outer expression
member or tip 46a as well as a reference member 48a. As shown, the
reference member 48a has aperture 88 and skin contacting portion 82
with skin contacting surface 86. Like the embodiment before, the
expression tip 46a has angled expression surface 92 that surrounds
expression opening 84. In the illustrated embodiment, the
expression tip 46a is glued to the housing 98, and in the another
embodiment, the expression tip 46a is integrally formed with the
housing 98. It should be understood that the expression tip 46a can
be attached to the housing 98 in other manners as generally know by
those skilled in the art. As mentioned above, the penetration depth
of the lancet 50 is control by a fixed stop in the actuation
mechanism, such as with a SOFTCLIX brand lancing device. It
contemplated that the lancet 50 in the sampling device 40a can be
constructed to have a fixed penetration depth or an adjustable
penetration depth, as in the manner described above for the
previous embodiment by adjusting registration between the reference
member 48a and the lancet body 52.
[0073] As mentioned above, the sampling device 40a of the
embodiment illustrated in FIGS. 6-9 is designed to automatically
retract the skin contacting portion 82 of the reference member 48a
from the expression opening 84 when expressing fluid from an
alternate site A. Normally, as depicted in FIG. 6, the skin
contacting portion 82 of the reference member 48a is positioned
within the expression opening 84. To automatically retract the
reference member 48a, the sampling device 40a incorporates a
retraction mechanism 110 that includes one or more cam arms 112
pivotally mounted to the housing 98. In the illustrated embodiment,
the retraction mechanism 110 incorporates a pair of cam arms 112,
but it should be appreciated that the retraction mechanism 110 can
have more or less cam arms 112 than is shown. As depicted in FIGS.
6 and 8, the cam arms 112 pivot about housing pivot pins 114, which
are received in pivot slots 116 defined in the housing 98. Each of
the cam arms 112 extend through cam arm openings 118 in the housing
98 and engage at one end a cam groove or surface 120 that is
defined in the guide arms 106. The other end of each of the cam arm
112 is engage with the reference member 48a through aperture pin
122 that is received in cam slot 124 defined in the reference
member 48a. In the illustrated embodiment, pin 122 extends within a
cavity 123 (FIG. 8) defined in each cam arm 122.
[0074] During lancing, the skin contacting portion 82 of the
reference member 48a is positioned in the expression opening 84 in
order to control the penetration depth of the lancet 50. As
illustrated in FIG. 6, the spring 100 biases the sleeve 96 away
from the expression tip 46a which in turn, through the guide arms
106, orients the cam arms 112 so as to position the reference
member 48a in the expression opening 84. When expressing bodily
fluid from an incision I formed at an alternate site A, the skin
contacting portion 82 of the reference member 48a is retracted from
the expression opening 84 such that the bodily fluid can be
expressed from the alternate site using the wider expression
opening 84. To retract the reference member during expression, the
user grasps the device 40a by sleeve 96 and presses the expression
tip 46a against the skin S. Referring to FIG. 7, while the device
40a is pressed against the skin S, the sleeve 96 slides in
direction E along the housing 98, and the spring 100 becomes
compressed. The stiffness of the spring 100 is selected such that
spring 100 will compress during expression, but will typically not
compress during lancing. As the sleeve 96 slides along the housing
98, the guide arms 106 pivot the cam arms 112 such that the
reference member 48a is retracted into the device 40a. Once the
user ceases pressing the device 40a against the skin S, the spring
100 returns the sleeve 96 to the original position shown in FIG. 6,
and the cam arms 112 return the reference member 48a back into the
expression opening 84.
[0075] An incision forming member 130 according to another
embodiment of the present invention will now be described with
reference to FIGS. 10-13. As illustrated in FIGS. 10 and 11, the
incision forming member 130 includes a body portion 132, a
reference member 133, a safety cover 134 and a lancet 136. In one
embodiment, the body portion 132, the reference member 133 and the
safety cover 134 are made of plastic; while lancet 136 is made of
metal. As should be appreciated, these components can be made of
other materials. The body portion 132 has a pair of opposing
notches 138 that are used secure the incision forming member 130 to
the bodily fluid sampling device. To protect the user from being
accidentally cut by the lancet 136, the safety cover 134 covers the
lancet 136 before use. In addition, the safety cover 134 can be
used to ensure the sterility of the lancet 136. When the incision
forming member 130 needs to be used, the safety cover 134 can then
be removed from the lancet 136, as illustrated in FIGS. 11-13. In
one form of the present invention, the safety cover 134 is
integrally molded with the body portion 132 such that the safety
cover 134 can be removed by twisting the cover 134 off the body
portion 132. In another form, the safety cover 134 is separate from
the body portion 132. Like the previous embodiments, the lancet 136
in FIG. 11 is configured to form an incision in the skin. By way of
nonlimiting example, the lancet 136 can be a blade, a needle or the
like.
[0076] In the embodiment illustrated in FIG. 11, the reference
member 133 is attached to the body 132 of the incision forming
member 130 in order to control the penetration depth of the lancet
136. As shown, the incision forming member 130 is received inside
the expression member 46. The retraction mechanism 93 used in the
illustrated embodiment is spring 94, which is engaged between the
expression member 46 and the reference member 133. The reference
member 133 has contact portion 82 with skin contacting surface 86
that controls the penetration depth of the lancet 136. After the
incision is formed, the incision forming member 130 along with the
reference member 133 are retracted by spring 94 such that the
contact portion 82 is removed from the expression opening 84 in the
expression member 46. By retracting the contact portion 82 of the
reference member 133, the larger expression opening 84 can be used
to express bodily fluid. It is contemplated, however, that the
reference member 133 can be retracted in other manners. For
instance, incision forming member 130 can be incorporated into a
SOFTCLIX brand lancing device that can be used to actuate and
retract the incision forming member 130. To adjust the penetration
depth of the lancet 136, the reference member 133 and the body
portion 132 are threadedly mated together. For example, the
reference member 133 and the body portion 132 can be threadedly
mated during the molding process for the parts. As shown in FIG.
11, the reference member 140 has an internally threaded portion 140
that engages an externally threaded portion 142 on the body portion
132 of the incision forming member 130. Further, the reference
member 133 has one or more wing members 144 extending therefrom
that engage spring 94 and are used to help turn the reference
member 133 relative to the body portion 132. For instance, as shown
in FIGS. 12 and 13, the penetration depth of the lancet 136 can be
reduced by rotating the reference member 133 in a counterclockwise
direction C. It should be appreciated that the incision forming
member 130 can be threaded differently such that the penetration
depth is increased by rotating the reference member 133 in the
counterclockwise direction C.
[0077] An incision forming member assembly 150 according to another
embodiment of the present invention is illustrated in FIG. 14. As
shown, the assembly 150 includes a body 152 and lancet 136 attached
to the body 152. In the body 152, living hinges 154 (or other
spring means) resiliently attach a reference member portion 155 to
the remainder of the body 152. Notches 138 are defined in the body
152 to secure the body to a holder 156. In the illustrated
embodiment, the holder has external threads 158 that mate with
internal threads 160 on depth control member 162. The depth control
member 162 has a contact edge 164 configured to contact a stop
flange 166 on the reference member portion 155. Distance D3 between
edge 164 and stop flange 166 controls the penetration depth of the
lancet 136. Assembly 150 further includes a safety cover 168 that
covers the lancet 136 in order to protect the user and provide a
sterile environment for the lancet 136. In the reference member
portion 155, a skin contact portion 170 extends from the stop
flange 166 along the lancet 136. Between the skin contact portion
170 and the safety cover 168, a groove or an area of weakness 172
is formed so that the cover 168 can be detached from the skin
contact portion 170 to expose the lancet 136. Once the cover 168 is
detached, a skin contacting surface 174 is formed at groove
172.
[0078] Assembly 150 is used in conjunction with an expression
member 46 of the type described above. As previously mentioned,
variations in skin height due to factors, such as the pressure
applied to the skin, the type of skin and the skin location, can
significantly alter the penetration depth of traditional lancing
devices. Assembly 150 is constructed to contact the skin before
lancing will occur, which in turn provides a reference surface for
controlling the penetration depth into the skin. During lancing,
the skin contact portion 155 extends through the expression opening
84 in the expression member 46, and the skin contacting surface 174
of assembly 150 contacts the skin. As the skin contacting surface
174 is pressed against the skin by the actuation of the lancet
assembly 150, the living hinges 154 are compressed until the stop
edge 164 contacts flange 166. As previously mentioned, the distance
D3 between edge 164 and flange 166 controls the penetration depth
of the lancet 136. Increasing distance D3 by rotating the depth
control member 162 relative to holder 156 deepens the penetration
depth of the lancet 136. In contrast, reducing the distance D3
between edge 164 and flange 166 decreases the penetration depth of
the lancet 136. The living hinges 154 aid in retracting the lancet
136 from the incision. When assembly 150 is retracted after lancing
the skin, the contact portion 155 is removed from the expression
opening 84 of the expression member 46, thereby providing a wider
opening in which the bodily fluid can be expressed.
[0079] A lancing assembly 180 according to a further embodiment of
the present invention will now be described with reference to FIGS.
15-17. Lancing assembly 180 integrates a number of features into a
single device; while at the same time allows for sterilization of
the lancet without affecting the test strip. Assembly 180 includes
an incision forming member 182, test media 184, and a carrier 186.
As shown, the incision forming member 182, which is used to form an
incision in the skin, has a head 188, a lancet 190, a pry member
192, and a safety cover 194. The head 188 and the cover 194 are
positioned at opposite ends of the lancet 190, and the pry member
192 is positioned along the lancet 190, between the head 188 and
the cover 194. In the illustrated embodiment, the head 188 has a
pair of lock notches 196 for locking the incision forming member
182 in an armed position. The lancet 190 in the illustrated
embodiment is a needle. However, it should be appreciated that
lancet 190 can include other types of instruments that are used to
from incision, such as blades for example. The pry member 192 has a
pair of pry surfaces 198 that are angled towards the lancet 190. To
make insertion of the incision forming member 182 into the carrier
easier, surfaces 198 are rounded. One of the many functions of the
safety cover 194 includes covering tip 200 of the lancet 190 (see
FIG. 17) in order to maintain the sterility of the lancet 190.
Moreover, the cover 194 protects users from accidentally cutting
themselves. As illustrated, the cover 194 in the illustrated
embodiment has a general cylindrical shape with an alignment flange
202 extending therefrom at one end. The cover 194 further has an
opening 204 that is normally sealed so as to maintain the sterility
of the lancet tip 200. In one form, the head 188 and the pry member
192 are made from a hard plastic; the cover 194 is made of a soft
plastic; and the lancet 190 is metallic. As should be appreciated,
these components can be made from other types of materials.
[0080] The test media 184 is used for determining analyte levels in
the bodily fluid sample. As should be appreciated, analyte levels
can be determined through the chemical, electrical, electrochemical
and/or optical properties of the bodily fluid sample collected on
the test media, to name a few. For example, the test media 184 in
the illustrated embodiment is a chemically reactive reagent test
strip. Typically, reagent test strips are sensitive to thermal
and/or chemical processes required for sterilization. The
sterilization process can affect the results generated by the test
media 184, and therefore, recalibration of the test media 184 is
required after sterilization. In the embodiment illustrated in
FIGS. 15-17, the incision forming member 182 can be separately
sterilized such that the test media 184 does not have to go through
the same sterilization process as the incision forming member 182.
After sterilization, the incision forming member 182 can be
installed in the carrier 186, thereby eliminating the need to
recalibrate the test media 184.
[0081] Referring to FIGS. 15 and 16, the carrier 186 has a pair of
lock arms 206 that define a receptacle 208 in which the head 188 is
locked when the lancet 182 is in the armed position, as is shown in
FIG. 17. Each lock arm 206 has a lock tab 210 that is constructed
to engage a corresponding notch 196 in the head 188. Between the
lock arms 206, the carrier has a connector 211 with a slot 212 in
which the lancet 190 is slidably received. The carrier 186 further
includes a pair of living hinges 214 that connect the lock arms 206
to sampling portion 216 of the lancing assembly 180. As shown, the
living hinges 214 have notches 218 that allow the living hinges 214
to bend. Each of the living hinges has two outwardly opening
notches 220 that are located proximal the connector 211 and the
sampling portion 216. Between the outwardly opening notches 220,
each living hinge 214 has an inwardly opening notch 222. The living
hinges 214 have expansion members 224 that are connected together
by a tamper evidence link 226. Each expansion member has a pry
surface 228, and the pry surfaces 228 are constructed to define a
pry member cavity 230 that receives the pry member 192 of the
incision forming member 182. In the illustrated embodiment, the pry
surfaces 228 are angled and are concavely shaped to coincide with
the shape of the surfaces 198 on the pry member 192. The carrier
186 further includes a cover receptacle 280 that defines a safety
cover cavity 282 in which the safety cover 194 of the incision
forming member 182 is received. As illustrated in FIG. 15, cavity
282 includes an alignment slot 284 that is configured to receive
the alignment flange 202 of the safety cover 194.
[0082] As shown in FIG. 15, the sampling portion 216 of the carrier
186 defines a test media cavity 286 in which the test media 184 is
housed during use. Inside the test media cavity 286, the sampling
portion 216 further has a capillary channel 288. The capillary
channel 288 is configured to allow the lancet 182 to extend
therethrough during lancing and is configured to draw fluid onto
the test media 184 during sampling. In cavity 286, the test media
184 is slightly spaced away from the sampling portion 216 in order
to define a flat capillary space for spreading the fluid sample
across the test media 184. As depicted, a cross member 289 extends
across a portion of the channel 288 proximal the cover 194 so as to
prevent removal of the incision forming member 182 when the
assembly 180 is armed. The channel 288 fluidly communicates with an
aperture 290 defined in skin contacting portion 292. The skin
contacting portion 292 has a skin contacting surface 294 that
contacts and flattens the skin around the aperture 290 so that the
lancet 182 can cut an incision with a precise depth.
[0083] To arm the assembly 180, the head 188 is pushed into the
receptacle 208 such that the lock arms 206 engage and lock with the
notches 196 in the head 188, as is illustrated in FIG. 17. During
arming, the pry member 192 breaks the tamper evidence link 226 by
prying the expansion members 224 apart, which in turn bends the
living hinges 214. As mentioned above, the tamper evidence link 226
provides a visual indicator of prior arming or use of the device
180. When assembly 180 is armed, the tip 200 of the lancet 182
pierces through the sealed opening 204 in the cover 194 and extends
into the capillary channel 288. By extending across the capillary
channel 288, the cross member 289 helps to prevent accidental
removal of the incision forming member 182 after arming. It should
be noted that that the test media 184 is not shown in FIG. 17 so
that the tip 200 of the lancet 182 can be viewed when in the armed
position and that the test media 184 is typically attached before
arming in the illustrated embodiment. Moreover, it should be noted
that the tip 200 of the lancet 182 in one form is typically
positioned within aperture 290 proximal the skin contacting surface
294.
[0084] After arming, assembly 180 can be used to form an incision
in the skin. To form the incision, the assembly 180 is installed in
a sampling device in one embodiment of the present invention. In
one form, the assembly 180 is armed by the sampling device, and in
another form, the assembly is armed before installation in the
sampling device. During lancing, the skin contacting surface 292
contacts the skin, and the tip 200 of the lancet 190 is driven
through opening 290. In one embodiment, the incision forming member
182 is actuated by a hammer, or a similar device, in order to
strike the head 188 of the incision forming member 182. In one
embodiment, the penetration depth of the lancet 190 is controlled
by an adjustable holder for assembly 180 of the type similar to the
one described below with reference to FIG. 22. In another
embodiment, distance D4 between the pry member 192 and the cover
194 controls the penetration depth of the lancet 190. As the
incision forming member 182 is driven, the living hinges 214 are
compressed. After the tip 200 of the lancet 190 is fully extended,
the compressed living hinges 214 recoil, thereby retracting the
lancet 190. The bodily fluid from the incision formed by the lancet
190 is collected through aperture 290 and is distributed across the
test media 184 via capillary channel 184. The annular space defined
in aperture 290 between the lancet 190 and the skin contacting
portion 292 forms a low volume capillary for transporting the
fluid. The fluid is then transferred to the flat capillary defined
between the test media 184 and the sampling portion 216 in cavity
286. In one form, the gaps are small (0.1 mm or less) to promote
transfer of the fluid between the annular and flat capillaries. In
one embodiment, venting of the capillaries is accomplished via
slots or channels 295 formed around cavity 286.
[0085] A sampling device 300 according to another embodiment of the
present invention is illustrated in FIGS. 18-20. FIG. 18 depicts
the device 300 prior to lancing; while FIGS. 19 and 20 show the
device 300 during lancing. Sampling device 300 includes a head
member 302 that has a pair of living hinges or leaf springs 304.
The head 302 defines a pair of openings 306 that are used to secure
the device 300. As shown, the ends of the leaf springs 306 that are
opposite the head 302 are received in slots 306 defined in safety
cover 308. The safety cover 308 encapsulates lancet 190 to protect
the lancet 190 from outside contamination. In the illustrated
embodiment, the lancet 190 is attached to the head 302, and in
another embodiment, the lancet 190 abuts the head 302. The cover
308 has an encapsulating surface 310 that covers the lancet 190.
Before lancing, as depicted in FIG. 18, the encapsulating surface
310 of the safety cover 308 covers the lancet 190. During lancing,
as illustrated in FIG. 19, the tip 200 of the lancet 190 pierces
the encapsulating surface 310 of the cover 308. In one embodiment,
the encapsulating surface 310 includes soft foam and/or rubber that
surround the tip 200 of the lancet 190 inside the cover 308.
Following lancing of the skin, the leaf springs 304, which were
bent during lancing, retract the lancet 190 from the skin.
[0086] Like the device shown in FIGS. 15-17, the sampling device
300 illustrated in FIGS. 18-20 allows test media 312 to be
assembled to the remainder of the device after the lancet 190 has
been sterilized. As illustrated in FIG. 20, the test media 312 is
attached to the safety cover 308, and the test media 312 has an
overhang portion 313 that extends past surface 310 on the cover
308. In one embodiment, the test media 312 is glued to the covers.
As should be appreciated, the test media 312 can be attached in
other manners. In the illustrated embodiment, the test media 312 is
operable to test analyte levels electrochemically. In another
embodiment, the test media 312 is operable to test analyte levels
optically. It should be understood that the test media 312 can test
analyte levels using other techniques. Proximal to surface 310, the
test media 312 incorporates a capillary portion 314 for drawing
bodily fluid into the test media 312 for testing. The overhang
portion 313 of the test media 312 ensures that capillary 314 is in
close proximity to the skin. The capillary portion 314 is
surrounded by a skin contacting surface 315 that acts as the
reference surface for controlling the penetration depth of the
lancet 190. In FIG. 20, the head 302 and the safety cover 308 have
opposing stop surfaces 316 and 318 that control the penetration
depth of the lancet 190. In one embodiment, the distance between
stop surfaces 316 and 318 determines the penetration depth of the
lancet 190. In another embodiment, spacers with varying thicknesses
are placed between the stop surfaces 316 and 318 to adjust the
penetration depth of the lancet 190.
[0087] FIGS. 21-23 illustrate a sampling device 330 according to
another embodiment of the present invention. As shown in FIGS.
21A-B and 22, device 330 includes a housing 332, a lancet or blade
334 slidably received in the housing 332, and test media 336.
Housing 332 has first 338 and second 340 sides that are attached
together through a bead 342 to form a blade cavity 344 in which
blade 334 is received. In the illustrated embodiment, both the
first 338 and second 340 sides are generally flat to give the
sampling device an overall flat appearance. In one form, bead 342
is an adhesive bead that adheres the first 338 and second 340 sides
together. Conceptually, the housing 332 can be further subdivided
into separate head 346 and skin contacting 348 portions. Blade 334
is attached to the head 346 and is slidable within blade cavity 344
in the skin contacting portion 348 of the housing 332. The first
side 338 of the housing 332 defines a living hinge or leaf spring
350 that connects the head 346 to the skin contacting portion 348
of the housing 332. The head 346 can further have notches 352 for
securing device 330 to a holder. FIGS. 21 and 22 illustrate the
leaf spring 350 in a flexed state when blade 334 is extended from
the housing 332 through opening 353. Next to opening 353, the first
side 338 of the housing 332 has a skin contacting edge 354 that
acts as a reference surface for controlling the penetration depth
of the blade 334. Opposite the edge 354, the second side 340 of the
housing 332 has a capillary slot 356 for drawing fluid via
capillary action into the blade cavity 344. As shown, the capillary
slot 356 in the illustrated embodiment has a gradual tapered shaped
from opening 353 to improve fluid flow from the incision into the
blade cavity 344. As shown in FIG. 23, capillary slot 356 as well
as opening 353 can be covered with a safety cover 358 that can be
used to maintain the sterility of blade 334 and to protect the user
from injury.
[0088] In the blade cavity 344, especially between the blade 334
and the second side 340 of the housing 332, a gap is formed around
the blade 334 for drawing bodily fluid from the incision to the
test media 336 via capillary action. In one embodiment, the side of
the blade 334 that faces the test media 336 is coated and/or
incorporates hydrophilic material, and the opposite side is coated
and/or incorporates hydrophobic material. As should be appreciated,
this construction improves the transfer of the fluid onto the test
media 336. The test media 336 can be of the type described above
and can be attached to the housing 332 in a number of manners. For
instance, the test media 336 can be a chemically reactive reagent
strip that is glued to the housing. To ensure proper calibration of
the test media 336, the test media 336 can be attached to the
housing 332 after the blade 334 has been sterilized. Once attached,
the test media 334 defines portion of the blade cavity 344 and
fluid from slot 356 can be drawn to the test media 332 through the
blade cavity 334.
[0089] A holder 360 for device 330 that is operable to adjust the
penetration depth of the blade 334 is illustrated in FIG. 22.
Holder 360 has a cover 362 with a receptacle 364 in which device
330 is received and a depth control mechanism 366 that is coupled
to the cover 362. In the illustrated embodiment, a test media view
window 368 is defined in the cover 362 so that the test media 336
can be viewed. Window 368 can allow the test media 336 to be
analyzed optically. The depth control mechanism 366 has a depth
adjustment wheel 370 that is rotatably coupled to a bearing member
372 through rod 374, and the bearing member 372 is attached to the
cover 362. The rod 374 has a gear 376 that is engageable with an
actuation gear 378. Wheel 380 only partially extends around rod
374, thereby defining a gap 380 that allows device 330 to be
mounted in holder 360. As shown, the wheel 380 has a series of
steps 382 of graduated thickness, and the steps 382 of wheel 380
can be rotated through a slot 384 in the cover 362.
[0090] To insert device 330 into holder 360, the actuation gear 378
rotates the wheel 380 such that gap 380 is positioned in the slot
384. Device 330 is then slid into the receptacle 364 so that the
head 346 of the device 330 is slid past slot 384. Next, the
actuation gear 378 rotates the wheel 380 such that at least one of
the steps 382 is positioned in the slot 384 between the head 346
and the skin contacting portion 348, thereby securing the device
330 to the holder 360. The step 382 with the appropriate thickness
can be positioned in the slot 384 between the head 346 and the skin
contacting portion 348 so as to control the penetration depth of
the blade 334. During lancing, as the holder 360 is driven towards
the skin, the skin contacting edge 354 contacts the surface of the
skin. As the holder 360 is driven further, the skin contacting
portion 348 of the housing 332 slides within the receptacle 364
towards the head 346 of the device 330 such that the blade 334 is
uncovered to lance the skin. The skin contacting portion 348 of the
housing 332 continues to retract until it engages the selected step
382 on the wheel 380. As previously mentioned, the thickness of the
step 382 controls the penetration depth of the blade 334.
Afterwards, the leaf spring 350, which became flexed during
lancing, extends portion 348 of the housing 332 so as to recover
the blade 334. Once the incision is formed, the skin contacting
edge 354 can remain positioned against the skin (or positioned
proximal to the skin) such that the fluid from the incision is
drawn via capillary action into the blade cavity 344. In one
embodiment, the fluid is drawn onto the side of the blade that
faces the test strip 336, which is coated with hydrophilic
material. From the blade cavity 344, the fluid is then deposited
onto the test strip 336 for testing.
[0091] A lancing device 400 according to a further embodiment,
which incorporates components similar to the embodiments
illustrated in FIGS. 1-9, will now be described with reference to
FIGS. 23-28. Lancing device 400 according to the illustrated
embodiment is configured to automatically increase the size of the
expression opening and maintain the larger sized expression opening
when fluid is expressed from an alternate site. As depicted in FIG.
23, the lancing device 400 includes an outer expression member or
tip 46b, a reference member 48b, a cam arm 112a, a sleeve 96a, a
latch mechanism 402, a housing 98a, spring 100 and nut 102. Similar
to the embodiments illustrated in FIGS. 1-9, the reference member
48b has skin contacting portion 82 with skin contacting surface 86
that surrounds aperture 88 (see FIG. 27). The expression tip 46b in
FIG. 28 has an expression surface 92, which has a conical form, and
the expression surface 92 surrounds expression opening 84. The
expression tip 46b is attached to the sleeve 98a, which is slidably
received in the housing 98a. In one form of this embodiment, the
expression tip 46b is glued to the sleeve 98a. However, it is
contemplated that the expression tip 46b can be secured in other
manners.
[0092] As depicted in FIG. 23, the sleeve 98a defines a pair guide
slots 404 that are configured to receive a pair of guide bosses 406
on the reference member 48b. It should be appreciated that the
reference member 48b can have more or less guide bosses 406 than is
shown. In the illustrated embodiment, the guide bosses 406 have a
generally rectangular shape so as to align the reference member 48b
in the guide slots 404. Around the sleeve 98a, the housing 96a has
stop arms 408 with stop members 410 that are adapted to engage a
stop flange 104a on the sleeve 98a. In the illustrated embodiment,
the penetration depth of the lancet 50 is controlled by the
mechanism that is used actuate the lancet 50, such as in a SOFTCLIX
brand lancing device. It is contemplated, however, that the
penetration depth of the lancet 50 can be controlled in other
manners. For instance, the distance between the stop flange 104a
and the stop members 410 can be used to control the penetration
depth of the lancet 50. On one of the stops 408, arm 412, the cam
arm 112a is pivotally mounted. Both arm 412 and cam arm 112a have
pivot pin openings 414 and 416 in which a pivot pin 418 is
received, as is shown in FIGS. 23-24. The cam arm 112a has a link
portion 420 that join two actuation members 422 that give the cam
arm 112a a general u-shape. The end of each actuation member 422,
opposite link 420, has a reference member engaging slot 424 that
are configured to engage cam arm pins 426 that extend from the
guide bosses 406 on the reference member 48b. In the illustrated
embodiment, the actuation members 422 have a generally bowed shape
so as to fit around the sleeve 98a. Between pivot pin openings 416
and slots 424, each actuation member 422 has a sleeve engaging pin
428 that are received in a corresponding pivot pin opening 430 in
the sleeve 98a. On the cam arm 112a, a lock arm portion 430 with a
lock tab 432 extends from one of the actuation members 422.
Referring to FIGS. 25 and 26, one end of the latch arm 402 is
pivotally mounted to the housing 96a, and the other end of the
latch arm 402 has a latch notch 434 configured to engage the lock
tab 432. In the illustrated embodiment, gravity is used to position
the latch arm 402 such that the latch arm is able to engage the
lock tab 432. In another embodiment, the latch arm 402 incorporates
a spring for biasing the latch arm 402 toward the housing 96a such
that the latch arm 402 is able to engage the lock tab 432 on the
cam arm 112a. It should be appreciated that latch arm 402 can be
biased in other manners.
[0093] By being able to accurately control the penetration depth of
the lancet 50, the device 400 is able to safely lance and express
fluid from both fingertips and alternate sites. As previously
discussed, the actuation mechanism for the lancet 50 controls the
penetration depth of the lancet 50. With reference to FIGS. 27-28,
spring 100 is secured between the stop flange 104a of the sleeve
98a and the nut 102, which is secured to the housing 96a. Normally,
as shown in FIG. 27, the spring 100 biases the sleeve 98a with
respect to the housing 96a such that the cam arm 112a positions the
reference member 48b in expression opening 84 of the expression tip
46b so that the penetration depth can be precisely controlled
during lancing. Typically, device 400 is only used to lance the
fingertip and is not used to express fluid from the fingertip
because fingertips tend to provide an adequate fluid supply without
the need to express the fluid. When expressing from an alternate
site, as depicted in FIG. 28, the user grips and presses the
housing 96a towards the skin. As the housing 96a slides relative to
the sleeve 98a, the cam arm 112a pivots such that the reference
member 48b is retracted from the expression opening 84. The
retraction of the reference member 48b creates a large opening in
which bodily fluid from an alternate site can be expressed. To
ensure that the reference member 48b remains in the retracted
position during expression of fluid from an alternate site, the
lock tab 432 on the cam arm 112a locks with the latch arm 402.
After the fluid has been expressed, the latch arm 402 can be
disengaged from the lock tab 432 to return the device 400 to its
original configuration, as illustrated in FIG. 27.
[0094] A fluid sampling device 450 according to a further
embodiment of the present invention is illustrated in FIGS. 29-31.
With reference to FIG. 29, the device 450 has an actuation knob 452
at one end and a skin contacting or expression member 454 at the
other end. The actuation knob 452 is rotatably mounted on housing
456, and the knob 452 can be rotated in order to change the shape
and size of the expression member 454. Like the previous
embodiments, device 450 is configured to precisely control the
penetration depth of a lancet for safety purposes and is
configurable to express fluid from finger as well as from alternate
sites. As illustrated in FIG. 30, device 450 includes lancet 130
that is able to control and adjust its penetration depth, as was
described above with reference to FIGS. 10-13. It should be
appreciated that device 450 can use other types of lancing devices
that can control penetration depth of the lancet, such as the
embodiments illustrated in FIGS. 14-23. The expression member 454
has a lancet opening 458 through which lancet 130 is able to extend
during lancing.
[0095] As briefly mentioned above, the expression member 454 is
reconfigurable to change shapes depending on the expression site.
For instance, the sampling device 450 in FIG. 30 is configured to
express fluid from a fingertip or similar site, and in FIG. 31,
device 450 is in a configuration to create a larger expression
opening in order to express fluid from an alternate site. To
accomplish this, the sampling device 450 has an inner tube 460
slidably mounted inside an outer tube 462. The inner tube 460 has a
proximal end that is attached to the knob 452. The distal end of
the inner tube 460 has a flange 464 that is rotatably coupled to a
collar 464 such that the flange 464 is able to rotate relative to
the collar 464. In the expression member 454, living hinges 466
connect the collar 464 to the outer tube 462, and each living hinge
466 has a relief notch or portion 468 that allows the living hinge
to bend. As shown, the living hinges 466 are covered by a covering
470 that defines opening 458. In the illustrated embodiment, the
covering 470 is made of a flexible material that is attached to the
living hinges 466. By way of nonlimiting example, the covering 470
can be made of flexible plastic, rubber or the like. The collar 466
provides structural support around opening 458 so that the device
450 is able to express fluid from incision I in fingertip F.
However, usually expressing the fingertip F is not required in
order to obtain an adequate fluid sample.
[0096] The sampling device 450 further incorporates an actuation
mechanism 472 that, in conjunction with knob 452, retracts the
inner tube 460 inside the outer tube 462, thereby expanding the
expression member 454 to the configuration illustrated in FIG. 31.
With reference to FIGS. 29 and 30, the actuation mechanism 472 in
the illustrated embodiment includes a guide pin 474 that extends
from the inner tube 460 into a guide channel 476 in the outer tube
462. As depicted in FIG. 29, the guide channel 476 extends along a
generally spiral shaped path on housing 456. Although the guide
channel 476 is visible on the outside of the device in FIG. 29, it
is contemplated that the guide channel 476 can be enclosed so as to
be invisible from the outside. By way of example, the actuation
mechanism 472 operates in a fashion similar to that of a lipstick
dispenser. As the knob 452 is rotated relative to the housing 456
in a clockwise fashion, as viewed from the proximal end of the
device 450, the guide pin 474 slides within channel 474 such that
the distal end of the inner tube 460 is drawn inside of the outer
tube 462. While the inner tube 460 retracts inside the outer tube
462, the living hinges 468 bend to create an expression opening 476
that is larger than opening 458 such that the device 450 is able to
express fluid from alternate site A. As illustrated in FIG. 31, the
living hinges 466 bend at middle notch 478 to form an outer
expression edge 480 that defines expression opening 476 with an
expression surface 482. In the illustrated embodiment, the
expression surface 482 has a conical shape. It is contemplated that
the shape of the expression member 454 can be changed in other
manners. In a further embodiment, the actuation mechanism 472 and
inner tube 460 are eliminated such that the user manually pushes in
the expression member 454 to create a dented portion on the
expression member 454 so that fluid can be expressed from an
alternate site.
[0097] As should be appreciated, the above-described devices can be
incorporated into an integrated sampling device that further
includes a capillary tube or some other wicking means for drawing
the bodily fluid sample onto a test strip while the device remains
positioned over the incision. Sampling device 330, which was
described above with reference to FIGS. 21-23, is an example of one
such integrated device. As previously mentioned, device 330 remains
in contact with the skin as the fluid sample is drawn into the
blade cavity 344 and deposited onto the test strip 336. It is
contemplated that other devices described herein can be modified to
collect and test a fluid sample in a similar fashion.
[0098] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that only the preferred embodiment has been shown
and described and that all changes and modifications that come
within the spirit of the invention are desired to be protected. All
publications, patents, and patent applications cited in this
specification are herein incorporated by reference as if each
individual publication, patent, or patent application were
specifically and individually indicated to be incorporated by
reference and set forth in its entirety herein.
* * * * *