U.S. patent application number 11/276237 was filed with the patent office on 2006-07-13 for methods and apparatus for expressing body fluid from an incision.
This patent application is currently assigned to Roche Diagnostics Operations, Inc.. Invention is credited to Edward P. Perez, Charles C. Raney, Jeffrey N. Roe.
Application Number | 20060155316 11/276237 |
Document ID | / |
Family ID | 46277747 |
Filed Date | 2006-07-13 |
United States Patent
Application |
20060155316 |
Kind Code |
A1 |
Perez; Edward P. ; et
al. |
July 13, 2006 |
METHODS AND APPARATUS FOR EXPRESSING BODY FLUID FROM AN
INCISION
Abstract
A sample of a body fluid such as blood or interstitial fluid is
obtained from a body by lancing a portion of a user's skin,
preferably in an area other than a finger tip, to form an incision.
After the needle has been removed from the incision, a force is
applied to depress the skin in a manner forming a ring of depressed
body tissue in surrounding relationship to the incision, causing
the incision to bulge and the sides of the incision to open,
whereby body fluid is forced out through the opening of the
incision. A stimulator member is mounted to an end of a
lancet-carrying housing for applying the force. The stimulator
member can be movable relative to the housing, and can be either
heated or vibrated to promote movement of the body fluid.
Inventors: |
Perez; Edward P.; (Redwood
City, CA) ; Roe; Jeffrey N.; (San Ramon, CA) ;
Raney; Charles C.; (Camdenton, MO) |
Correspondence
Address: |
WOODARD, EMHARDT, MORIARTY, MCNETT & HENRY LLP
111 MONUMENT CIRCLE, SUITE 3700
INDIANAPOLIS
IN
46204-5137
US
|
Assignee: |
Roche Diagnostics Operations,
Inc.
Indianapolis
IN
|
Family ID: |
46277747 |
Appl. No.: |
11/276237 |
Filed: |
February 20, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10764261 |
Jan 23, 2004 |
|
|
|
11276237 |
Feb 20, 2006 |
|
|
|
09879991 |
Jun 14, 2001 |
6706000 |
|
|
10764261 |
Jan 23, 2004 |
|
|
|
09542040 |
Mar 31, 2000 |
6464649 |
|
|
09879991 |
Jun 14, 2001 |
|
|
|
09285021 |
Apr 1, 1999 |
6066103 |
|
|
09542040 |
Mar 31, 2000 |
|
|
|
08975978 |
Nov 21, 1997 |
5964718 |
|
|
09285021 |
Apr 1, 1999 |
|
|
|
Current U.S.
Class: |
606/181 ;
600/583 |
Current CPC
Class: |
A61B 5/15117 20130101;
A61B 10/0045 20130101; A61B 5/150022 20130101; A61B 5/150068
20130101; A61B 5/15194 20130101; A61B 5/157 20130101; A61B 5/1519
20130101; A61B 5/150412 20130101; A61B 5/15186 20130101; A61B
2010/008 20130101; A61B 5/15113 20130101; A61B 5/150083 20130101;
A61B 5/15111 20130101; A61B 5/150076 20130101 |
Class at
Publication: |
606/181 ;
600/583 |
International
Class: |
A61B 17/32 20060101
A61B017/32; A61B 5/00 20060101 A61B005/00 |
Claims
1. A sampling device, comprising: a constricting member configured
to pinch tissue to form a puckered area of the tissue; a
stimulating member positioned to contact the puckered area of the
tissue; a skin-lancing medium to form an incision in the puckered
area of the tissue; and wherein the stimulating member is
configured to spread the incision open and the constricting member
is configured to constrict fluid flow from the puckered area to
enhance expression of the body fluid from the incision.
2. The device of claim 1, wherein the constricting member is
constructed of a pliable material that flexes to pinch the
tissue.
3. The device of claim 1, wherein the constricting member includes:
a plurality of pivot arms; and a plurality of biasing members each
coupled to a corresponding one of the pivot arms to pivot the pivot
arms for pinching the tissue.
4. The device of claim 1, wherein the stimulator member includes
circumferentially spaced interruptions.
5. The device of claim 1, wherein the stimulator member includes a
flexible membrane.
6. The device of claim 1, wherein the stimulator members include
first and second stimulator members that are interconnected to move
axially in mutually opposite directions.
7. The device of claim 1, further including a second stimulator
member chosen from the group consisting of, a heating mechanism for
heating the stimulating member or constricting member, and a
vibrator mechanism for vibrating the stimulating member or
constricting member.
8. The device of claim 1, further comprising: means for pinching
the tissue, wherein the means for pinching the tissue includes the
constricting member; means for spreading the incision open, wherein
the means for spreading the incision open includes the stimulating
member; and means for forming the incision, wherein the means for
forming the incision includes the skin-lancing medium
Description
PRIOR APPLICATIONS
[0001] The present application is a divisional of U.S. patent
application Ser. No. 10/764,261 filed Jan. 23, 2004, which is a
continuation of U.S. patent application Ser. No. 09/879,991 filed
Jun. 14, 2001, now U.S. Pat. No. 6,706,000, which is a
continuation-in-part of U.S. patent application Ser. No. 09/542,040
filed Mar. 31, 2000, now U.S. Pat. No. 6,464,649, which is a
continuation of U.S. patent application Ser. No. 09/285,021 filed
Apr. 1, 1999, now U.S. Pat. No. 6,066,103, which is a continuation
of U.S. patent application Ser. No. 08/975,978 filed Nov. 21, 1997,
now U.S. Pat. No. 5,964,718. The above-identified patent
applications and patents are hereby incorporated by reference in
their entirety.
FIELD OF THE INVENTION
[0002] This invention relates to a body fluid testing device and
methods for obtaining samples of blood fluid for analysis.
BACKGROUND OF THE INVENTION
[0003] Many medical procedures in use today require a relatively
small sample of body fluid, for example in the range of 0.1-50
micro liters. It is more cost effective and less traumatic to the
patient to obtain such a sample by lancing or piercing the skin at
a selected location, such as the finger or forearm, to enable the
collection body fluid. With the advent of home use tests for the
self monitoring of blood glucose, there is a requirement for a
simple procedure which can be performed in any setting without a
person needing the assistance of a professional.
[0004] One device which is commonly utilized to form an opening in
the patient's skin is a lancets. Lancets generally have a rigid
body and a sterile lance which protrudes from one end. The lancet
may be used to pierce the skin, thereby enabling the collection of
a body fluid sample from the opening created. The body fluid sample
is transferred to a test device or collection device. Body fluid is
most commonly taken from the fingertips, where the supply is
generally excellent. However, the nerve density in this region
causes significant pain in many patient's. Sampling of alternative
sites, such as earlobes and limbs is sometimes practiced to lessen
the pain. These sites are also less likely to provide excellent
body fluid samples and make body fluid transfer directly to test
devices difficult. Examples of body fluids which may be utilized to
test for glucose are blood and interstitial fluid.
[0005] Repeated lancing in limited surface areas, such as
fingertips, results in callous formation. This leads to increased
difficulty in drawing body fluid and increased pain.
[0006] To reduce the anxiety of piercing the skin and the
associated pain, many spring loaded devices have been developed
wherein the device automatically triggers in response to an applied
force. Thus the user cannot anticipate the exact timing of the
piercing, thus they are less likely to pull the device away during
use. The following two patents are representative of the devices
which were developed in the 1980's for use with home diagnostic
test products.
[0007] U.S. Pat. No. 4,503,856, Cornell et al., describes a spring
loaded lancet injector. The reusable device interfaces with a
disposable lancet. The lancet holder may be latched in a retracted
position. When the user contacts a release, a spring causes the
lancet to pierce the skin at high speed and the retract. The speed
is important to reduce the pain associated with the puncture.
[0008] Levin et al., U.S. Pat. No. 4,517,978 describes a blood
sampling instrument. This device, which is also spring loaded, uses
a standard disposable lancet. The design enables easy and accurate
positioning against a fingertip so the impact site can be readily
determined. After the lancet pierces the skin, a bounce back spring
retracts the lancet to a safe position within the device.
[0009] In home settings it is often desirable to collect a body
fluid sample in order to enable a user to perform a test at home,
such as glucose monitoring. Some blood glucose monitoring systems,
require that the blood sample be applied to a test device which is
in contact with the test instrument. In such situations, bringing
the finger to the test device poses some risk of contamination of
the sample with a previous sample that may not have been properly
cleaned from the device. Glucose monitoring devices may utilize a
blood sample in many ways, though the two most common methods for
collection are a paper strip and a capillary tube. Monitors that
utilize a paper strip, require the patient to pierce a finger or
appropriate location, withdraw a small sample of blood from the
pierced area, such as by squeezing, and then placing the paper
strip in physical contact with the blood sample and waiting until
the paper strip absorbs the blood. Monitors that utilize a
capillary tube for fluid collection, require the patient to follow
the process described above, except that a paper strip is not
utilized, instead a small capillary tube is placed over the sample
until a sufficient amount of blood is withdrawn into the capillary
tube and to the glucose testing area of the testing device.
[0010] Many times due to dexterity problems or poor eye site it can
be difficult for the patient to either bring the body fluid sample
to the testing area or to bring a capillary tube to the fluid
sample. Additionally, some patient's have a fear of bodily fluids,
such as blood, and would prefer not to see this type of body
fluid.
[0011] Amira Medical Inc. introduced a new method for home glucose
testing. Amira's device AtLast 7, tests blood glucose levels by
taking blood from the skin of the forearm, which is a much less
sensitive than the fingertips. This device has been very well
received by both the diabetic community as well as the blood
glucose measurement industry.
[0012] Haynes U.S. Pat. No. 4,920,977 describes a blood collection
assembly with a lancet and micro-collection tube. This device
incorporates a lancet and collection container in a single device.
The lancing and collection are two separate activities, but the
device is a convenient single disposable unit for situations when
sample collection prior to use is desirable. Similar devices are
disclosed in Sarrine U.S. Pat. No. 4,360,016 and O'Brian U.S. Pat.
No. 4,924,879.
[0013] Jordan et al., U.S. Pat. No. 4,850,973 and U.S. Pat. No.
4,858,607 disclose a combination device which may be alternatively
used as a syringe-type injection device and a lancing device with
disposable solid needle lancet, depending on configuration.
[0014] Lange et al., U.S. Pat. No. 5,318,584 describes a blood
lancet device for withdrawing blood for diagnostic purposes. This
invention uses a rotary/sliding transmission system to reduce the
pain of lancing. The puncture depth is easily and precisely
adjustable by the user.
[0015] Suzuki et al., U.S. Pat. No. 5,368,047, Dombrowski U.S. Pat.
No. 4,654,513 and Ishibashi et al., U.S. Pat. No. 5,320,607 each
describe suction-type blood samplers. These devices develop suction
between the lancing site and the end of the device with the lancet
holding mechanism withdraws after piercing the skin. A flexible
gasket around the end of the device helps seal the end around the
puncture site until adequate sample is withdrawn from the puncture
sire or the user pulls the device back.
[0016] Garcia et al., U.S. Pat. No. 4,637,403 discloses a
combination lancing and blood collection device which uses a
capillary action passage to conduct body fluid to a separate test
strip in the form of a micro porous membrane. It is necessary to
achieve a precise positioning of the upper end of the capillary
passage with respect o the membrane in order to ensure that the
body fluid from the passage is transferred to the membrane. If an
appreciable gap exits therebetween, no transfer may occur.
[0017] It is difficult for a user to determine whether a
sufficiently large drop of body fluid has been developed at the
incision for providing a large enough sample.
[0018] Single use devices have also been developed for single use
tests, i.e. home cholesterol testing, and for institutional use to
eliminate the cross-patient contamination multi-patient use.
Crosman et al., U.S. Pat. No. 4,869,249, and Swierczek U.S. Pat.
No. 5,402,798, also describe disposable, single use lancing
devices.
[0019] The disclosures of the above patents are incorporated herein
by reference.
[0020] An object of the present invention is to provide a one-step
procedure and device for testing glucose levels in body fluids.
[0021] Another object of the present invention is to provide an
apparatus that withdraws a body fluid sample and provides an
individual with a body fluid glucose level reading.
[0022] Even with the many improvements which have been made, the
pain associated with lancing remains a significant issue for many
patients. The need for blood sampling and the fear of the
associated pain is also a major obstacle for the millions of
diagnosed diabetics, who do not adequately monitor their blood
glucose due to the pain involved. Moreover, lancing to obtain a
blood sample for other diagnostic applications is becoming more
commonplace, and a less painful, minimally invasive device is
needed to enhance those applications and make those technologies
more acceptable.
[0023] An object of the present invention therefore, is to provide
a device and a method for obtaining a sample of bodily fluid
through the skin which is virtually pain free and minimally
invasive, particularly by penetrating less sensitive areas of the
skin.
[0024] Furthermore, known lancing devices include manually actuable
buttons for triggering the lance-driving mechanism once the user
has placed the device against his/her skin. Because the user knows
the precise instant when the lancet will be triggered and pain will
be felt, there is a tendency for the user to jerk or raise the
device at the instant of triggering, which can lead to inconsistent
skin penetration, or possibly no penetration. Therefore, a further
object of the invention is to provide a lancing device which
eliminates such a tendency on the part of the user.
[0025] Therefore, it is another object of the invention to provide
a lancet carrier which eliminates the above-mentioned
shortcomings.
[0026] Another object of this invention is to provide a method
which can result in a sample of either blood or interstitial fluid,
depending on the sample site and the penetration depth utilized.
While there are no commercially available devices utilizing
interstitial fluid (ISF) at this time, there are active efforts to
establish the correlation of analytes, such as glucose, in ISF
compared to whole blood. If ISF could be readily obtained and
correlation is established, ISF may be preferable as a sample since
there is no interference of red blood cells or hematocrit
adjustment required.
[0027] Another object of this invention is to provide a method by
which the drawn sample is collected and may be easily presented to
a testing device, regardless of the location of the sample site on
the body. This approach helps with infection control in that
multiple patients are not brought in contact with a single test
instrument; only the sampling device with a disposable
patient-contact portion is brought to the test instrument.
Alternatively, the disposable portion of a test device may be
physically coupled with the sampler so the sample can be brought
directly into the test device during sampling. The test device may
then be read in a test instrument if appropriate or the testing
system can be integrated into the sampler and the test device can
provide direct results displayed for the patient.
[0028] It is a further object of the invention is to provide a
device for minimally invasive sampling comprising a reusable
sampler and disposable sample lancet and collection device.
SUMMARY OF THE INVENTION
[0029] The present invention involves a method of obtaining a
sample of fluid from a body. The method comprises applying a
skin-lancing medium against a skin surface to form an incision
therein, removing the skin-lancing medium from the incision; and
thereafter applying a force to depress the skin in a manner forming
a ring of depressed body tissue in surrounding relationship to the
incision, causing the incision to bulge and the sides of the
incision to open, whereby body fluid is forced out through the
opening of the incision.
[0030] The invention also relates to a device for sampling body
fluid which comprises a housing having an open end, and a skin
lancing mechanism for applying a skin-lancing medium against a skin
surface to form an incision therein and then remove the
skin-lancing medium from the incision. A stimulator member is
mounted to the housing at the open end thereof for movement
relative to the housing. The stimulator member extends about a
longitudinal axis of the housing and is adapted to engage the skin
surface to bulge and open the incision in response to a pressing of
the end face against the skin surface.
[0031] The invention also relates to a device for expressing body
fluid from a lanced skin surface, which comprises a housing, and a
stimulator mechanism mounted to the housing at an end thereof. The
stimulator mechanism includes a generally circular array of
stimulator elements each mounted to the housing for movement toward
and away from a longitudinal axis of the housing. An actuator is
mounted to the housing for displacing the stimulator elements
toward the axis.
[0032] The invention also relates to a device for expressing body
fluid from a lanced skin surface, which comprises a housing and a
stimulator member mounted on the housing at an end thereof. The
stimulator member comprises a coil spring which is compressible
toward the housing in response to being pushed against a user's
skin in surrounding relationship to a lanced portion thereof.
[0033] Another aspect of the invention relates to a device for
expressing body fluid from a lanced skin surface which comprises a
housing and a hollow stimulator member mounted at an end of the
housing and adapted to engage a user's skin surface in surrounding
relationship to a lanced portion thereof. In order to promote the
flow of body fluid, the stimulator member can be heated, or
vibrated. If vibrated, the stimulator member applies an ultrasonic
frequency to the skin surface.
[0034] The invention also relates to a device for expressing body
fluid from a lanced skin surface which comprises a housing and a
hollow stimulator member mounted at an end of the housing for
longitudinal movement relative to the housing and adapted to
contact a user's skin surface in surrounding relationship to a
lanced portion thereof. A motor is mounted in the housing and a
reciprocatory mechanism is connected to the motor to be driven
thereby, and is operably connected to the stimulator member for
reciprocating the stimulator member along a longitudinal axis of
the stimulator member.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The objects and advantages of the invention will become
apparent from the following detailed description of preferred
embodiments thereof in connection with the accompanying drawing in
which like numerals designate like elements and in which:
[0036] FIG. 1 is a longitudinal sectional view through a blood
sampling device according to a first embodiment of the invention,
with the lancet carrier in an unarmed condition;
[0037] FIG. 2 is a view similar to FIG. 1, with the lancet carrier
in an armed condition;
[0038] FIG. 3 is a view similar to FIG. 2 after the lancet carrier
has been triggered and a lancet is penetrating the skin;
[0039] FIG. 4 is a fragmentary view similar to FIG. 1 after an
incision has been formed;
[0040] FIG. 5 is a view similar to FIG. 4 showing a stimulator
member of the device being depressed to cause the incision to bulge
and open;
[0041] FIG. 6 is a view similar to FIG. 5 after a stimulating
action has been performed to form a drop of blood at the open end
of the incision;
[0042] FIG. 7 is a fragmentary longitudinal sectional view through
a second embodiment of the invention;
[0043] FIG. 8 is a fragmentary longitudinal sectional view taken
through a third embodiment of the invention;
[0044] FIG. 9 is a side elevational view of a fourth embodiment of
the invention pressed against a skin surface;
[0045] FIG. 10 is an end view of the device depicted in FIG. 9;
[0046] FIG. 11 is a view similar to FIG. 9 after the device has
been compressed against the skin surface to bulge and open an
incision;
[0047] FIG. 12 is an end view of the device in the condition
depicted in FIG. 11;
[0048] FIG. 13 is a fragmentary longitudinal sectional view taken
through a fifth embodiment of the invention while in a first state
of operation;
[0049] FIG. 14 is a view similar to FIG. 13 with the device in a
second condition of operation;
[0050] FIG. 15 is a fragmentary longitudinal sectional view taken
through a sixth embodiment of the invention in a first condition of
operation thereof;
[0051] FIG. 16 is a view similar to FIG. 15 with the device in
another condition of operation;
[0052] FIG. 17 is a view similar to FIG. 16 of yet a further
condition of operation of the device;
[0053] FIG. 18 is a side elevational view, partly in longitudinal
section of yet another embodiment of the invention;
[0054] FIG. 19 is a longitudinal sectional view taken through still
a further embodiment of the invention;
[0055] FIG. 20 is a longitudinal sectional view of a blood lancing
device according to a seventh embodiment of the invention while in
a first condition or operation thereof;
[0056] FIG. 21 is an end view of the device in the condition
depicted in FIG. 20;
[0057] FIG. 22A is a view similar to FIG. 20, with the lancet
carrier in an armed condition;
[0058] FIG. 22B is a partial cross-sectional side view of the
lancing device wherein the lancet has penetrated the patient's
skin;
[0059] FIG. 22C is a view similar to FIG. 22A, illustrating the
bulge which forms in the patient's tissue, wherein the stimulating
member stretches the skin open for expressing a body fluid
sample;
[0060] FIG. 23 is an end view of an alternative embodiment of the
stimulating member of the present invention;
[0061] FIG. 24 is a cross-sectional side view of the alternative
embodiment of the stimulating member illustrated in FIG. 23;
[0062] FIG. 25 is an end view of another alternative embodiment of
the stimulating member of the present invention;
[0063] FIG. 26 is a partial cross-sectional side view of a lancing
device including a stimulating member and a constricting
member;
[0064] FIG. 27 is a partial cross-sectional side view of the
lancing device of FIG. 26 in use;
[0065] FIG. 28 is a partial cross-sectional side view of the
lancing device of FIG. 26 in use illustrating a bulge of tissue
formed by the constricting member;
[0066] FIG. 29 is a partial cross-sectional side view illustrating
the lancing action and spreading of the formed incision by the
stimulating member;
[0067] FIG. 30 is a partial cross-sectional side view of an
alternative embodiment of a lancing device including a stimulating
member and a constricting member;
[0068] FIG. 31 is a partial cross-sectional side view of the
lancing device of FIG. 30 illustrating the formation of an incision
within a bulge of tissue;
[0069] FIG. 32 is a partial cross-sectional side view of the
lancing device of FIG. 31 illustrating the spreading of the
incision by the stimulating member; and
[0070] FIG. 33 is a side view illustrating a glucose monitoring
device in accordance with the present invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0071] A lancing device 10 (see FIG. 1) according to one preferred
embodiment of the invention comprises an outer housing 12 having
upper and lower portions 14, 16 connected together, and an inner
housing 18 fixed to the outer housing.
[0072] Mounted for vertical reciprocation in the upper portion 14
of the outer housing 12 is a cocking mechanism 20 comprising a pull
handle 22 to which is fixedly secured a hollow draw tube 24. Fixed
to an inner wall of the draw tube 24 is a draw ring 26.
[0073] Situated within the draw tube 24 is a draw bar 30 having a
pair of flexible hooks 32 at its upper end. The hooks are
releasably latched to a sleeve 34 which is movably disposed within
the draw ring 26. A coil compression spring 36 acts between a
flange 33 of the sleeve 34 and an inner flange 38 of the draw ring
26.
[0074] A trigger sleeve 35 is mounted within the lower portion 16
of the outer housing 12. A lower end of the trigger sleeve rests
upon a first outer flange 37A of the inner housing, and a second
outer flange 37B of the inner housing rests upon an inner
projection 39 of the trigger sleeve.
[0075] At its lower end the draw bar 30 frictionally holds a
skin-lancing medium in the form of a disposable lancet 40 in which
a needle 42 is disposed. The draw bar 30 includes a flexible latch
finger 44 that has a projection 45 adapted to be received in a hole
46 of the inner housing 18 (see FIG. 2) when the device is armed. A
trigger member 49 is mounted in a hole 47 of the trigger sleeve 35
and includes an arm 48 extending partially into the hole 46. The
trigger member 49 includes an inclined cam follower surface 50.
[0076] A coil compression spring 52 acts between a top wall 54 of
the inner housing 18 and a shoulder 56 of the draw bar.
[0077] Slidably disposed within a lower end of the lower portion of
the outer housing is a firing tube 60 which includes an upper cam
surface 62. Fixed to a lower end of the firing tube 60 is an outer
hollow stimulator member in the form of a cylindrical ring 64,
having an end surface 65 of generally frusto-conical shape so as to
be oriented at a downward and inward inclination to generally face
a longitudinal axis A of the device.
[0078] Disposed coaxially within the firing tube 60 and outer
stimulator ring 64 is an inner hollow stimulator member also in the
form of a cylindrical ring 66 having a frusto-conical end surface
67 also oriented at a downward and inward inclination.
[0079] The end surfaces 65 and 67 are of circular configuration
when viewed along the axis A, other configurations, such as
polygonal, oval, etc., are possible.
[0080] A coil compression spring 68 acts between an upper end of
the outer stimulator ring 64 and a downwardly facing shoulder 70 of
the inner stimulator ring 66.
[0081] The inner stimulator ring 66 includes a lance stop flange 72
adapted to be engaged by a lance ring 74 of the lancet 40 as will
be explained.
[0082] The first flange 37A of the inner housing rests upon a
support sleeve 80 which, in turn, rests upon an upper end of the
inner stimulator ring 66.
[0083] In practice, when a fluid sample, such as blood or
interstitial fluid, is to be taken from a user's body, a lancing
device according to the present invention can be used to minimize
pain. To do so, a region of the user's body having less sensitivity
than, for example, a fingertip, is selected. Such a low-sensitivity
region could be the user's forearm for example. Initially, the
handle 22 is pulled up to raise the drawbar 30 until the projection
45 of the latch finger 44 snaps into the hole 44 of the inner
housing 18, as shown in FIG. 2. Simultaneously, the spring 52 is
compressed.
[0084] If the outer stimulator ring 64 is pressed against the
user's skin S, e.g., on the selected forearm region FA, the ring 64
and its cam surface 62 are moved upwardly to displace the trigger
radially inwardly, whereupon the projection 45 of the latch finger
44 is disengaged from the hole 46. Accordingly, the spring 52
expands to displace the drawbar 30 downwardly so that the needle 42
punctures the skin sufficiently deep to cut capillaries in the
superficial vascular plexus, as shown in FIG. 3. Simultaneously,
the spring 68 is compressed. The extent of displacement of the
drawbar 30 is limited
[0085] by engagement between the lance ring 74 with the lance stop
72.
[0086] Once lancing has occurred, the compressed spring 68 expands
to raise the drawbar, as well as the needle 42 and inner stimulator
ring 66 from the skin (see FIG. 4).
[0087] The user then alternately applies and releases a downward
force on the outer housing 12. Each time that a downward force is
applied, the end face 65 of the outer stimulator ring 64 exerts a
downward force F which depresses a ring-shaped portion of the skin
and body tissue which is disposed in surrounding relationship to
the wound or incision I, causing the wounded area to bulge while
pulling apart the sides of the wound (see FIG. 5). Hence, fluid
such as blood or interstitial fluid is trapped and pressurized so
that it travels upwardly through the pulled-open end of the wound
since the surrounding ring of depressed skin and body tissue
restricts the outward flow of fluid. That action is enhanced by the
fact that the force F is inclined inwardly toward the axis A to
force the fluid toward the bulged area.
[0088] When the downward force is released, the sides of the wound
close, and fresh fluid flows toward the area of the wound to
replace fluid which had been forced upwardly through the wound. As
the downward force is reapplied, the above-described action is
repeated and additional fluid is forced through the wound.
Eventually, this "pumping" action results in the formation of a
suitably large drop D of fluid (FIG. 6).
[0089] It will thus be appreciated that the present invention
enables an ample supply of blood, interstitial fluid or other body
fluid to be obtained relatively painlessly from areas of the body
which typically possess lesser amounts of such fluid as compared
with the highly sensitive fingertip region.
[0090] Note that each time that the downward force is applied to
the outer housing, the outer stimulator ring 64 moves upwardly
relative to the inner stimulator ring 66 so that the end surface 67
of the inner ring 66 also contacts the skin surface S at a location
inwardly of the outer face 65, thereby promoting the displacement
of fluid inwardly toward the wound. However, the present invention
can be practiced by a single stimulator ring arrangement 64A as
shown in FIG. 8.
[0091] While the surfaces 65, 67 are continuous, i.e.,
non-interrupted, it may be desirable to provide either or both of
those surfaces with circumferentially spaced recesses 80 as shown
in FIG. 7. The surface(s) 65A, 67A will still depress a ring of
body tissue surrounding the wound, but the areas of the ring
corresponding to the location of the recesses will be depressed to
a lesser extent than the other areas. Those lesser depressed areas
will provide less resistance to fluid flow and will thus enable
some fluid to leak past the ring, which would be beneficial in the
event that the user neglects to release the downward pressure on
the device.
[0092] The stimulator member need not be in the form of a ring. As
depicted in FIGS. 9-12, the stimulator member can be in the form of
a helical spring 90 formed by a flat strip 92. Such a spring would
function in somewhat similar fashion to the double-ring arrangement
of FIGS. 1-7 in that a stimulator surface gradually comes into
contact with the skin in a radially inward direction to aid in
propelling blood or interstitial fluid toward the center axis. In
that regard, FIGS. 9 and 10 depict a condition when the spring 90
is uncompressed. In contrast, FIGS. 11 and 12 depict a condition
wherein the spring is fully compressed. Shaded regions in FIGS. 10
and 12 represent contact between the spring and the skin. It will
be appreciated that during compression of the spring, the contact
region of the spring progresses gradually radially inwardly,
causing blood or interstitial fluid to be pushed toward the axis A
and thus toward the bulged area of the skin.
[0093] Depicted in FIGS. 13 and 14 is yet another alternative
embodiment wherein the outer stimulator ring 64B is interconnected
to the inner stimulator ring 66B by levers 100 which are pivoted to
the firing tube 60B. Thus, upward sliding movement of the outer
ring 64B is transmitted as a downward force to the inner ring 66B
to slide the latter downwardly and intensify the pumping
action.
[0094] A further embodiment is depicted in FIGS. 15-17 wherein the
firing tube 60C has a carrier tube 102 affixed at a lower end
thereof. Pivotably mounted on the carrier tube 102 is a circular
array of levers 104 each having an upper and lower end, each lower
end carrying a stimulator element in the form of a roller 106. Each
lever 104 is rotatable about an axis extending orthogonally
relative to the axis of the housing.
[0095] An inner ring 110 is slidable up and down, either by manual
force, or by a motor-driven cam (e.g., of the type disclosed later
in connection with FIG. 19). That ring 110 has a beveled cam face
112 formed on its lower end. When the device is pressed against the
skin, following a lancing procedure, the ring 110 is moved
downwardly so that the cam face 112 engages rollers 108 mounted on
upper ends of the levers. Hence, the levers 104 are rotated such
that the lower rollers 106 are displaced inwardly and upwardly at a
location disposed below the open end of the bulged wound to open
the wound and force blood or interstitial fluid toward the wound to
form a drop D. When the levers are not contacted by the cam face
112, the rollers 106 gravitate to a rest position shown in FIG. 15.
Repeated applications of the downward force cause the drop to
become gradually enlarged as explained earlier.
[0096] Depicted in FIG. 18 is an alternative embodiment similar to
that depicted in FIGS. 1-6, except that the lower end surface of
the outer stimulator ring 64D is provided with a hollow stimulator
element 114 which is electrically connected to a battery 116
mounted in an upper end of the device. The element can be either an
electrical resistance element (i.e., a heater) or a vibrator such
as a piezoelectric transducer, intended to stimulate fluid flow. A
heater will expand the capillaries and make the blood or
interstitial fluid less viscous and thus more flowable, in order to
increase the amount of the body fluid sample. On the other hand, if
the element 114 is a vibrator, such as a piezoelectric transducer,
vibrations can be created which stimulate the flow of body fluid.
This could be achieved by operating the transducer to produce
frequencies below 28,000 cycles per second. Alternatively,
ultrasonic frequencies, i.e., frequencies above 20,000 cycles per
second, will create interferometric wave patterns inside the skin
that cause contractions forcing fluid upwardly from the wound. The
frusto-conical shape 114A of the end face of the element will
optimize the creation of such wave patterns. It may be further
beneficial to employ a heater, such as an infrared emitter, mounted
in the housing which vasodilates the capillaries to increase blood
flow. Another advantage of the use of such frequencies is that only
minimal downward force to the device may be necessary since the
wave patterns may produce an ample pumping action.
[0097] FIG. 19 depicts a device which is not automatically fired,
but rather requires manual actuation of lever 130 against a bias of
a spring 132 to force a trigger 134 to push a projection 136 out of
a hole 138 (when the projection extends into that hole).
[0098] Mounted in a housing 140 of the device are a battery 142 and
electric motor 144 connected to the battery to be actuated thereby.
The motor 144 rotates a sleeve 146 about the axis A. The sleeve
includes a cam surface 148 which engages a follower roller 150
mounted on a tube 152.
[0099] As the sleeve 146 rotates, the cam surface pushes the tube
152 downwardly against the bias of a coil compression spring 154,
to push an inner stimulator ring 156 repeatedly against a skin
surface, thereby pumping blood to the top of an incision in the
same manner described earlier herein. The inner stimulator ring 156
reciprocates along the axis A within an outer stimulator ring 155.
This embodiment eliminates the need for the user to pulsate the
device up and down; the pumping operation is achieved automatically
in response to actuation of the lever 130.
[0100] The cam mechanism 146 can be used in an automatically firing
device, such as that disclosed in connection with FIG. 1.
[0101] Referring now to FIG. 20, there is shown a seventh
embodiment of the blood lancing device 10 of the present invention,
wherein like reference numerals have been utilized to denote the
same or similar elements of the previous embodiments described
above and shown in FIGS. 1-19. The lancing device 10 according to a
seventh embodiment includes an outer housing 12 having upper and
lower portions 14, 16 connected together, and an inner housing 18
fixed to the outer hosing.
[0102] Mounted for vertical reciprocation in the upper portion 14
of the outer housing 12 is a cocking mechanism 20 comprising a pull
handle 22 to which is fixedly secured a hollow draw tube 24. Fixed
to an inner wall of the draw tube 24 is a draw ring 26.
[0103] Situated with the draw tube 24 is a draw bar 30 having a
pair of flexible hooks 32 at its upper end. The hooks are
releasably latched to a sleeve 34 which is movably disposed with
the draw ring 26. A coil compression spring 36 act between a flange
33 of the sleeve 34 and an inner flange 38 of the draw ring 26.
[0104] A trigger sleeve 35 is mounted within the lower portion 16
of the outer housing 12. A lower end of the trigger sleeve rests
upon a first outer flange 37A of the inner housing, and a second
outer flange 37B of the inner housing rests upon an inner
projection 39 of the trigger sleeve.
[0105] At its lower end, the draw bar 30 frictionally holds a
skin-lancing medium in the form of a disposable lancet 40 in which
a needle or lancet 42 is disposed. The draw bar 30 includes a
flexible latch finger 44 that has a projection 45 adapted to be
received in a hole 46 of the inner housing 18 when the device is
armed. A trigger member 49 is mounted in a hole 47 of the trigger
sleeve 35 and includes an arm 48 extending partially into the hole
46. The trigger 46 includes an inclined cam follower surface
50.
[0106] A coil compression spring 52 acts between a top wall 54 of
the inner housing 18 and a shoulder 56 of the draw bar.
[0107] Slidably disposed within the lower end of the lower portion
of the outer hosing is a firing tube 60 which includes an upper cam
surface 62. Fixed to a lower end of the firing tube 60 is a
stimulator member 160 in the form of a flexible membrane, having a
tissue contacting surface 161. Referring now to FIG. 21 there is
shown an end view of the lancing device 10 of the present invention
illustrating the stimulator member 160. As shown, the stimulator
member 160 includes circumferentially spaced interruptions 163.
[0108] Referring now to FIGS. 22A through 22C, there are shown
partial longitudinal cross-sectional side views of the present
invention. Referring now to FIG. 22A there is shown the distal end
of the lancing device 10 as disposed over a potion of skin S to be
lanced in preparation for a body fluid sample to be obtained. As
shown in FIG. 22A, the tissue contacting surface 161 of the
stimulator member 160 contacts the patient's skin. The tissue
contacting surface 161 of the stimulator member 160 may be formed
having a raised area as shown in FIGS. 23-25, wherein the raised
surface contact the skin S thereby providing a friction force f
between the distal surface 161 and the skin S.
[0109] Referring now to FIG. 22B, wherein a force F has been
applied to the proximal end of the lancing device 10, wherein the
force F is translated to the lancet 42 and lancet holder 240,
thereby advancing the lancet into the patient's skin.
[0110] Referring now to FIG. 22C there is shown the lancet 42 in a
retracted position after the lancet 42 has penetrated the skin S to
a sufficient depth to cut capillaries in the superficial vascular
plexis to form an incision I as shown.
[0111] The tissue contacting surface 161 of the stimulator member
160 remains in contact with the skin as after the lancet has formed
an incision within the patient's skin and is thereby withdrawn from
the incision I. The force F applied to the proximal end of the
lancing device 10 causes the sleeve 280 to contact the skin,
wherein the skin yields to the applied force as shown in FIG. 22C.
The skin S forms a bulge about the incision I formed by the lancet.
The friction force f between the distal surface 161 and the skin S
retains the stimulator member upon the skin S. By retaining the
contacting surface 161 upon the skin S, the incision I is stretched
open, thereby allowing more body fluid to be expressed from the
incision. In one embodiment, the sleeve 180 causes fluid such as
blood or interstitial fluid to become trapped and pressurized
within the bulged area, so that the body fluid will travel upwardly
through the pulled-open incision I.
[0112] After a sufficient sample size has developed, the lancing
device 10 is removed from the patient's skin wherein the sample may
then be utilized in any manner desirable.
[0113] It shall be understood that the stimulator member 160 and
the lancing device 10 produce a sufficiently sized sample between
about 0.05 micro liters and 10 micro liters without the need for
repetitive motion as described above with regard to the other
embodiments of the present invention. In addition, the alternative
embodiment of the lancing device illustrated in FIGS. 20-22C may be
utilized with other methods and devices for producing a
sufficiently sized sample. For example, the lancing device 10 may
include vibration means (not shown), heating means (not shown),
vacuum means (not shown), each of which may be utilized to
encourage blood flow within the area to be sampled. Alternatively,
the area to be sampled may be stimulated using one of the methods
described above prior to using the lancing device 10.
[0114] The stimulator member 160 may be constructed of
bio-compatible materials such as polyvinyl chloride, silicon,
urethane, or similar flexible materials which are adapted to grip
and translate a frictional force between the tissue contacting
surface 161 and the patient's skin S thereby causing a wound to be
stretched open thereby allowing a greater amount of body fluid to
flow therefrom. In addition, the stimulator member 160 may be
formed of materials which are flexible such that a portion of the
stimulator member 160 will deform in use, though it shall be
understood in a preferred embodiment, the tissue contacting surface
161 remains substantially parallel with the skin surface as shown
in FIGS. 22A-22C.
[0115] Alternatively, it is contemplated that the stimulating
member 160 may be formed of a rigid material wherein the skin
contacting surface of the rigid stimulating member is adapted to
provide a friction force between the skin and the tissue contacting
surface such that the skin will be retained upon the tissue
contacting surface as described above. Additionally, the
stimulating member may be pivotally affixed to the sleeve 280
thereby allowing a rigid stimulator member to be utilized in the
same manner as a flexible member.
[0116] Referring now to FIGS. 23 and 24 the stimulator member 260
illustrated therein may be formed in generally the same manner as
that shown and described above, though the stimulator member 260 is
formed having a plurality of rings 261 disposed radially about an
aperture 266. In use, the plurality of rings 261 act on the skin S
with a frictional force such as that described and shown above. The
frictional force f retains the tissue contacting surface 261 of the
stimulator member 260 upon the skin surface S, whereby causing the
incision I to stretch open as described above.
[0117] Referring now to FIG. 25 there is shown yet another
alternative embodiment of the stimulator member 460 of the present
invention. The stimulator member 460 further includes a raised
member 462 extending from the tissue contacting surface 461. The
raised member 462 is disposed upon the tissue contacting surface
461 in a spiraling manner, such as that shown in FIGS. 9-11, and
25. In practice, the leading edge 463 of the spiraling raised
member 462 will contact the patient's skin first, thereafter as a
greater downward force is applied the remaining portion of the
spiraling raised member 462 will contact the patient's tissue. The
forced imparted by the spiraling raised member 462 will cause the
skin to bulge, in addition the constant spiraling motion will cause
the fluid under the skin to become concentrated within the center
of the bulge.
[0118] Referring now to FIG. 26 there is shown yet another
alternative embodiment in accordance with the present invention.
The lancing device 10 may further include a stimulating member 160
as described in detail above with regard to FIGS. 21 through 25. In
addition to the stimulating member 160, a constricting member 500
may be fixedly attached to the distal end 181 of the sleeve 180.
The constricting member 500 may be constructed of a pliable
material, wherein the constricting member 500 will flex as shown in
FIG. 28. Examples of materials which the constricting member 500
may be constructed of plastics such as polyethylene, polysilicone,
polyvinyl chloride, or alternatively of materials such as titanium,
aluminum, steel, stainless steel.
[0119] The constricting member 500 may be constructed as a separate
body which is then fixedly attached to the distal end 181 of the
sleeve 180 with an adhesive or mechanical fastener or other process
such as melting or fusion welding. Alternatively, the constricting
member 500 may be pivotally attached to the distal end 181 of the
sleeve 180 (not shown).
[0120] Methods of use relating to the lancing device 10 will be
described in relation to FIGS. 27-29. Referring now to FIG. 27
there is shown the lancing device 10 as disposed over an area in
which it is desired to express a sample of body fluid. As the force
F is applied to the lancing device 10 the force F is translated
through the constricting member 500 into component forces F' and
F''. As the force F increases, the component forces F' and F''
cause the patient's skin in contact with the distal end 501 of the
constricting member 500 to gather and form a pucker as shown in
FIG. 28, wherein the tissue contacting surface 161 of the
stimulating member 160 contacts the skin S.
[0121] In addition to forming the puckered area of skin as shown in
FIG. 28, when the force F is increased on the lancing device 10,
the pucker of skin is drawn into the distal end of the lancing
device 10. The pucker of skin is received by the tissue contacting
surface 161 of the stimulating member 160, wherein the stimulating
member may include a plurality of ridges to increase frictional
contact between the skin and the tissue contacting surface 161 of
the stimulating member 160. In addition to forming the pucker of
skin, a second force F''' is applied to the lance 42, thereby
driving the distal tip of a lance or needle into the pucker of skin
to form an incision therein as shown in FIG. 28.
[0122] The forces F' and F'' which the constricting member 500
applies to the skin cause the skin to form the pucker as described
above. Additionally, the forces F' and F'' cause body fluid to pool
within the pucker because the forces constrict or tourniquet
vessels under the surface of the skin thereby restricting the flow
of body fluid from these areas. Thus, by constricting the flow of
body fluid within the pucker a larger body fluid sample may be
obtained from the incision formed by the lance or needle.
[0123] Referring now to FIG. 29 there is shown the lancing device
10 wherein the lance or needle 42 has been retracted by spring
force K after an incision I has been formed in the patient's skin.
As shown in FIG. 29 as a greater force F.sub.2 is applied to the
lancing device 10, this causes the constricting member 500 to
further pinch the skin in addition to causing the incision to be
spread by the stimulating member 160 due to a friction force f
between the skin S and the tissue contacting surface 161 of the
stimulating member 160.
[0124] As a result of the stretching of the incision I, a greater
amount of bodily fluid may be expressed from the incision I.
Because a greater amount of body fluid may be expressed from the
incision I, the lancet device may not require a repeated motion as
described above in order to express a sufficiently sized sample of
body fluid. Though not shown in FIGS. 27-29, the lancing device 10
may include additional stimulating means such as heat, vibration,
ultrasound or other similar known methods or devices which are
utilized to increase body fluid flow within a localized area.
[0125] Referring now to FIGS. 30-32 there is shown an alternative
embodiment of a constricting member 600. Wherein the constricting
device 600 may be disposed about the sleeve 180 of the lancing
device 10 and adjacent the distal end 181 to the sleeve 180. The
constricting device 600 includes a plurality of arms 610 having a
distal end 611 and a proximal end 612, a biasing member 650 and a
pivot 660.
[0126] In accordance with the present invention, the proximal end
612 of the arm 610 may be pivotally attached to the sleeve 180. The
arm 610 may be pivotally attached to the sleeve through a pin and
block configuration as shown in FIGS. 30-32 or alternatively the
proximal end 612 may be integrally formed with the sleeve 180 and
pivot through the use of a live hinge or similar arrangement.
[0127] As described above the constricting device member 600
includes a biasing member 650. The biasing member 650 acts on the
arms 610 thereby directing the distal tips 611 of the arms 610 to
contact the skin S as shown and to provide forces F' and F''.
[0128] Referring now to FIGS. 31 and 32 there is shown the lancing
device 10 in use. The constricting member 600 acts upon the
patient's skin to form a pucker of skin which is received within
the distal end of the lancing device 10. It shall be noted that the
constricting member 600 acts upon the patient's skin in the same
manner as the constricting device 500 as described above with
reference to FIGS. 26 through 29. Wherein the constricting device
600 and stimulating member 160 act in conjunction with one another
to express a greater amount of body fluid from an incision formed
in the patient's skin.
[0129] The lancing device in accordance with the present invention
may be best utilized in areas where it is difficult to obtain a
sufficient sample size, such as a forearm, though it is desirable
to lance within this area because of the reduction in pain
associated with the lancing.
[0130] Referring now to FIG. 33, there is shown a further
alternative embodiment of a lancing device 700 in accordance with
the present invention, wherein the lancing device 700 further
includes a body fluid sampling and testing device. The lancing
device 700 may be utilized upon a patient's forearm or similar
area, wherein the stimulating member and constricting member in
conjunction with a needle or lancet produce a sample size of
sufficient volume wherein a test may be performed thereon. For
example, the lancing device 700 may be that which is shown and
described in co-pending U.S. Provisional Patent Application No.
60/296,950 filed Jun. 8, 2001, now abandoned, Attorney Dkt. No.
018176-385 and to co-pending U.S. Provisional Patent Application
No. 60/297,098 filed Jun. 8, 2001, now abandoned, Attorney Dkt. No.
018176-382, the entirety of which are hereby incorporated by
reference.
[0131] It will be appreciated that the present invention enables a
sampling of blood or interstitial fluid to be taken from areas of
the body, such as a forearm, that are less insensitive to pain,
despite the fact that those areas typically have relatively less
fluid as compared, for example, to fingertips (which are highly
sensitive to pain).
[0132] Therefore, there will be less reluctance on the part of
users to have a sampling procedure performed. For example,
diabetics who experience a relatively high fear of pain will be
less likely to neglect monitoring their blood glucose levels.
[0133] In lieu of using a lancet as a skin-lancing medium, other
skin-lancing media can be used, such as a laser, or known pneumatic
or hydraulic injectors of the type which inject pressurized gas or
liquid against the skin. Such auto injectors are sold by
Becton-Dickinson, for example, to inject insulin. By eliminating
the insulin and merely injecting the gas (e.g., air or nitrogen) or
liquid (e.g., water) at pressures above
[0134] 30 psi. an incision could be formed in the skin for taking
samples of body fluid. Advantageously, small particles could be
mixed with the gas to promote the tissue-cutting action. The
particles could comprise carbon particles of from 1 micron to 0.010
inches in diameter.
[0135] In addition to that which is described above, it is
contemplated that the lance or needle may remain within the
incision during the collection of the sample. Additionally a force
may be applied to the lance or needle to stimulate fluid flow from
the incision, for example the lance or needle may be vibrated to
express fluid from the incision. It shall be understood that the
terms "remain within the incision" shall mean to include the
instances where the lance or needle remains in contact with the
patient's tissue inside of the incision, or where the lance or
needle is withdrawn just distal the incision though remains in
fluid contact with the body fluid expressed from the incision.
[0136] Although the present invention has been described in
connection with preferred embodiments thereof, it will be
appreciated by those skilled in the art that additions, deletions,
modifications, and substitutions not specifically described may be
made without departing from the spirit and scope of the invention
as defined in the appended claims. In addition, each of the methods
and apparatuses described herein may be utilized with testing
systems and devices such as those which are contained within the
co-filed U.S. Patent Application having Ser. No. 60/297,187 filed
Jun. 8, 2001, now abandoned, entitled "Control Solution Packet and
Methods of Use for Bodily Fluid Sampling Devices;" U.S. Patent
Application having Ser. No. 60/296,950 filed Jun. 8, 2001, now
abandoned, entitled "Lancet Device Having Capillary Action;" U.S.
Patent Application having Ser. No. 60/297,045 filed Jun. 8, 2001,
now abandoned, entitled "Method of Sampling Interstitial Fluid for
Glucose Monitoring;" U.S. Patent Application having Ser. No.
60/296,989 filed Jun. 8, 2001, now abandoned, entitled "Cassette
for a Glucose Monitoring System;" and U.S. Patent Application
having Ser. No. 60/296,949 filed Jun. 8, 2001, now abandoned,
entitled "Test Media for Glucose Monitoring Systems;" the entirety
of which are herein incorporated by reference.
* * * * *