Cap for a Lancing Device
A cap for a lancing device for lancing dermal tissue is provided. The cap includes a cap body having a proximal end for connecting to the distal end of the housing of the lancing device and a contact ring attached to the distal end of the cap body. The contact ring includes an opening for <; i portion of the lancet of the lancing device to pass therethrough. The contact ring has a multi-contoured surface oriented generally about an axis distinct from the axis of motion of the lancet. The multicontoured surface is designed to pressure the dermal tissue to facilitate expression of a fluid sample after lancing the dermal tissue. The fluid sample can include blood, interstitial fluid, or both.
This application claims priority to provisional patent application Ser. No. 60/210,808 filed Jun. 9, 2000 and provisional patent application Ser. No. 60/261,513 filed Jan. 12, 2001, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTIONThe present invention generally relates to lancing devices for lancing dermal tissue and for withdrawing a fluid sample.
Lancets in conventional use generally have a rigid body and a sterile needle which protrudes from one end. The lancet may be used to pierce the skin, thereby enabling the collection of a blood sample from the opening. The blood is then transferred to a test collection device. Blood is most commonly taken from the fingertips, where there is generally an abundant supply. However, the nerve density in this region causes significant pain in many patients. Sampling of alternate sites, such as earlobes and limbs, is sometimes practiced to access sites which are less sensitive. These sites are also less likely to provide sufficient blood volume, and make blood transfer directly to test devices difficult.
Repeated lancing in limited surface areas (such as fingertips) results in callous formation. This leads to increased difficulty in drawing blood and increased pain to the user. To reduce the anxiety of piercing the skin and the associated pain, many spring loaded devices have been developed.
After puncturing the skin, conventional lancing devices are laid down and the free hand of the user squeezes blood from the puncture wound. This technique requires a clean storage site for the lancing device and a two-hand operation. Once the drop of blood is expressed from the lancing site, the user transfers the blood to a test strip of a suitable meter.
It is often desirable to collect the expressed sample from the patient and then introduce the sample to a test device in a controlled fashion. Some blood glucose monitoring systems, for example, require that the blood sample be applied to a test device which is in contact with a test instrument. In such situations, bringing the finger of a patient directly to the test device poses some risk of contamination from blood of a previous patient. With such systems, particularly in hospital settings, it is common to lance a patient, collect a sample in a micropipette via capillary action and then deliver the sample from the pipette to the test device.
However, these lancet devices do not extract (‘squeeze out’) a sufficient sample from the various surfaces for lancing. For example, the curved surface of a fingertip requires the right amount of pressure to be applied to extract blood quickly and efficiently from the patient. Therefore, there is a need for a lancet system that can accommodate the lancing of curved surfaces (e.g., fingertips) as well as flat surfaces (e.g., forearm or leg) to express sufficient volume of blood or interstitial fluid, while concomitantly reducing pain experienced by the user.
SUMMARY OF THE INVENTIONThe present invention provides a cap for a lancing device for lancing dermal tissue. The cap includes a cap body having a proximal end for connecting to the distal end of the housing of the lancing device and a contact ring attached to the distal end of the cap body. The contact ring includes an opening for a portion of the lancet of the lancing device to pass therethrough. The contact ring has a multi-contoured surface oriented generally about an axis distinct from the axis of motion of the lancet. The multi-contoured surface is designed to pressure the dermal tissue to facilitate expression of a fluid sample after lancing the dermal tissue. The fluid sample can include blood, interstitial fluid, or both.
In accordance with one aspect of the present invention, the cap body is transparent to facilitate viewing of the quantity of blood expressed.
In accordance with another aspect of the present invention, the multi-contoured surface comprises an outer radial portion oriented at a first angle relative to the axis of the contact ring and an inner radial portion proximate the opening and oriented at a second angle, distinct from the first angle, relative to the axis of the contact nng.
In accordance with a further aspect of the present invention, the cap is removably and replaceably connected to the distal end of the housing.
In accordance with another aspect of the present invention, a sleeve can be mounted about the cap body. The sleeve can be movable generally along the axis of motion of the lancet and relative to the cap body. The sleeve includes at least two legs for maintaining contact with the dermal tissue during expression of a blood sample after lancing the dermal tissue. In addition, the sleeve can be biased toward the distal end of the cap body, for example, by a spring.
In accordance with another aspect of the present invention, the cap body includes a contact ring having a multi-contoured surface oriented to create a radially inwardly extending pressure-gradient, which extends towards a central aperture.
In accordance with another aspect of the present invention, a cap for lancing curved dermal tissue is provided. The contact ring portion of the cap is comprised of a flexible material. The flexible material when placed against the lancing site conforms to the surface, and hence accommodates lancing of the curved dermal tissue to create a pressure gradient beneath the skin to express a suitable fluid sample. This flexible cap creates a pressure gradient and expresses dermal fluid on strongly curved and flat areas of the skin without having to change the cap or use a different lancing device.
In accordance with yet another aspect of the present invention, a lancing device for lancing dermal tissue is provided. The lancing device includes a housing, a lancet and a cap. The cap includes a cap body and a contact ring having a multi-contoured surface oriented generally about an axis distinct from the axis of motion of the lancet. The multi-contoured surface is designed to pressure the dermal tissue to facilitate expression of a fluid sample after lancing the dermal tissue. The fluid sample can include blood, interstitial fluid, or both.
These and other features and advantages of the present invention will be more fully understood by reference to the following detailed description in conjunction with the attached drawings in which like reference numerals refer to like elements through the different views. The drawings illustrate principles of the invention and, although not to scale, show relative dimensions.
The present invention is directed to a cap for use with a lancing device for lancing dermal tissue to express a fluid sample, such as blood, interstitial fluid, or both. We refer below to the expression of blood for purposes of simplicity, although it is intended to encompass the expression of interstitial fluid or both. The cap of the present invention is designed to facilitate the expression of blood after the dermal tissue is lanced by increasing the pressure on the dermal tissue surrounding the lancing site. This increase in pressure results in increased blood flow from the lancing site, thereby reducing the time necessary to express a sufficient quantity of blood and eliminating the need for placing the lancing device on a surface and using the other free hand to squeeze out the sample fluid.
Moreover, the cap of the present invention is particularly suited for collecting blood samples from lancing sites other than on the fingertip of the patient, which is the traditional location for collecting blood samples. Use of such alternative sites can be less painful to the patient and also allows the patient to “rest” his or her fingertip. Suitable alternative sites include, but are not limited to, the forearms, the upper arms, the thighs, the palms, and the abdomen of a patient. Blood sample collection at alternative sites can be problematic as manually applying sufficient pressure on the dermal tissue proximate the lancing site to collect the blood sample can be difficult and typically results in low yields. The cap of the present invention allows the user to increase the amount of pressure at the lancing site such that a sufficient quantity of blood can be expressed from the alternative sample site.
A cap 10 in accordance with one preferred embodiment of the present invention is illustrated in
The cap 10 includes a cap body 14 having a proximal end 32 and a distal end 34 as best illustrated in
Referring to
The cap body 14 can be constructed from a transparent, translucent or opaque material, such as a clear, transparent plastic, or includes a transparent portion forming a window to the interior of the cap body, or can be constructed of conventional non-transparent material. If transparent, the material should be sufficiently so to permit expressed blood to be viewed within the cap body 14. The transparency of the cap body 14 allows the user to view the amount of blood expressed for collection from the lancing site, as discussed in more detail below.
Referring to
The multi-contoured surface 22 is designed to pressure the dermal tissue to maximize blood flow rate from the periphery of the pressured area to the center of the lancing site and to facilitate the expression of a blood sample for collection. The term multi-contoured surface as used herein is intended to include two or more surfaces oriented at distinct angles with respect to each other and with respect to a common axis. The multi-contoured surface can extend inwardly from a vertical wall, or can extend inwardly from a flat surface extending radially inwardly from the vertical wall. Those of ordinary skill will recognize that the multi-contoured surface can include any selected number of surfaces. The surface can be, according to one practice, non-planar. In one embodiment described herein, the multi-contoured surface 22 is comprised of an outer radial portion 24 and an inner radial portion 26 proximate the opening 18. The outer radial portion 24 is preferably oriented at a first angle C relative to the second axis B. The inner radial portion 26 is preferably oriented at a second angle D, distinct from the first angle C, relative to the second axis B. The outer radial portion 24 and the inner radial portion 26 can have any selected surface feature or shape, e.g., can be linear, stepped, or curved. In the illustrated embodiment, the outer radial portion 24 is generally linear from the perimeter 28 of the contact ring 16 to the intersection with the inner radial portion 26. Alternatively, the outer radial portion 24 can be convex or concave in curvature. Additionally, the inner radial portion 26 is generally concave in curvature, but can also be linear or convex.
As shown in
The contact ring 16 can be constructed from plastic or other materials suitable for use in a medical instrument. The contact ring 16 can have a non-transparent color, such as white, that is distinct and in contrast from the color of the dermal tissue. A contrasting color allows the user to better visualize the quantity of expressed blood.
The contact ring 16 can be a separate, discrete component affixed to the cap body 14, or can be integrally formed with the cap body 14.
With reference to
The pressure profile 31 created by the cap 10 has pressure peaks 33 that coincide with the perimeter portion of the cap, or with the start of the multi-contoured surface 22. The pressure is a maximum at this portion since the cap contacts the skin of the user to a greater degree. When the surfaces of the multi-contoured surface extend inwardly towards the opening 18 and away from the skin, the overall pressure decreases. This forms a pressure gradient that extends from the outermost portion of the cap 10 to the opening 18. The illustrated pressure gradient 31 has decreases in a somewhat uniform manner across the surface 24, and in a more rapid manner across surface 26. Those of ordinary skill will recognize that the pressure profile will change as a function of the configuration of the contact ring.
According to an alternative embodiment of the invention, illustrated in
The illustrated multi-contoured surface 22′ includes two or more surfaces oriented relative to each other to form different, distinct angles. In particular, the multi-contoured surface 22′ includes a pair of surfaces 25 and 27. The radially outer surface 25 is oriented at a first angle relative to the axis B. The radially inner surface 27 is oriented at a second angle relative to the axis B different from the first angle. As described above, the surfaces 25 and 27 can have any selected shape or angle.
In use, the cap 10 is connected to the housing 12 of the lancing device and the dermal tissue is lanced by the lancet 30 passing through the opening 18 in the contact ring 16. The lancet 30 is then withdrawn into the cap 10 or the lancing device. The contact ring 16 is pressed into contact with the dermal tissue proximate the lancing site causing blood to exit the lancing site and enter the cap 10 through the opening 18. Dermal tissue is “squeezed” into contact with the outer radial portion 24 and the inner radial portion 26 of the multi-contoured surface 22. The mllti-contoured surface 22 facilitates blood expression by increasing the hydrostatic pressure on the dermal tissue in contact with the perimeter 28 of the contact ring 16. The hydrostatic pressure on the dermal tissue decreases as the slope of the outer radial surface 24 and the inner radial surface changes toward the opening 18. This inwardly extending pressure gradient is illustrated in
An alternative embodiment of the cap of the present invention is illustrated in
As illustrated in
The sleeve 60 is preferably slidable along an axis parallel to the first axis A, as indicated by arrow T in
A spring 70 or other biasing mechanism can be provided to bias the sleeve 60 toward the distal end of the cap 1 O. One skilled in the art will appreciate that the sleeve 60 is not limited to use with the cap 10 of the present invention, but can be used with the cap of any lancing device.
It is sometimes desirable to remove the cap 10 and the contact ring 16 from contact with the dermal tissue after lancing, for example, to remove pressure from the dermal tissue or to visibly inspect the lancing site. The sleeve 60 allows the user to maintain a portion of the lancing device, the legs 64A and 64B of the sleeve 60, in contact with skin when the cap 14 and the contact ring 16 are removed from contact with skin, as illustrated in
Referring to
Alternate embodiments of the cap of the present invention are illustrated in
The cap body 81 is constructed from transparent, translucent, or opaque material, such as clear or transparent plastic, or includes a transparent portion forming a window to the interior of the cap body. The material should be sufficiently transparent to allow the blood being expressed from within the cap body 81 to be viewed by the user. The transparency of the cap body 81 allows the view the amount of blood expressed for collection from the lancing, etc.
The contact ring 85 preferably employs a pair of pressure wings 82 sized and dimensioned to accommodate the sharp curve of the fingertip there between. The pressure wings 82 thus form a recess 87 for accommodating the finger of the user. This applies the correct amount of pressure to allow for the expression of blood.
Referring to
The illustrated contact ring 85 can be constructed from plastic or other materials suitable for use in a medical instrument. The contact ring 85 can have a non-transparent color that is distinct from the color of the fingertip. White is the preferred color of choice. A contrasting color allows the user to better visualize the quantity of blood expressed. The contact ring 85 can be a separate, discrete component affixed to the cap body 81, or can be integrally formed with the cap body 81.
When in use, the cap 80 is connected to the housing 12 of the lancing device, and the fingertip of the user is placed in the recess 87 formed by the pressure wings 82, 82. The lancet 30 of the device is deployed and passes through the opening 92 in the contact ring 85 to pierce the skin. The contact ring 85 is pressed into contact with the fingertip proximate to the lancing site to express blood. The multi-contoured surface 87 facilitates blood expression by creating a pressure gradient that extends radially inwardly towards the opening 92. According to an alternate embodiment, an anti-slip feature on the contact ring 85 prevents movement of the contact ring relative to the skin surface when the contact ring is pressed into contact with the fingertip. As discussed, the anti-slip feature can comprise a suitable anti-slip material affixed to the multi-contoured surface, or a roughened multi-contoured surface. Alternatively, the contact ring 85 can be constructed entirely of a suitable anti-slip material to provide an anti-slip feature.
The cap body 94 includes a connector 99 for removably and replaceably connecting a proximal end 98 of the cap body 94 to a distal end of the housing 12. For example, the connector 99 can be sized and shaped to fit the housing 12. Also, the cap 90 can be permanently affixed to the housing 12. Preferably, the cap 93 is removably and replaceably connected to the housing 12. The cap body 94 is preferably similar to cap body 81 of
The illustrated contact ring 95 has a multi-contoured surface 96 that extends from the periphery of the cap body 94 to the central opening 101. The multi-contoured surface 96 can include two or more surfaces disposed at distinct angles relative to each other and with respect to a common axis. For example, the illustrated multi-contoured surface 96 is comprised of an outer radial portion 96A, a middle portion 96B, and an inner radial portion 96C disposed proximate to the opening 101. The outer, middle and inner radial portions of the cap can have any selected surface feature or shape, e.g., can be linear, stepped, or curved. Moreover, the transition points between each surface 96A, 96B and 96C of the multi-contoured surface can have rounded, arcuate, or sharp surface features.
The illustrated contact ring 95 can be constructed from plastic or other materials suitable for use in a medical instrument. The contact ring 95 can have a non-transparent color that is distinct from the color of the fingertip. White is the preferred color of choice. A contrasting color allows the user to better visualize the quantity of blood expressed. Similarly to cap 80, the contact ring 95 can be separated, discrete component affixed to the cap body 94, or can be integrally formed with the cap body 94.
When in use, the cap 90 is connected to the housing 12 of the lancing device and the fingertip is placed in intimate facing contact with the ventral side finger and lanced by the lancet 30 passing through the opening 101 in the contact ring 96. The lancet 30 is withdrawn into the cap 90 or lancing device. The fingertip is squeezed into contact with the outer radial portion 96A, middle radial portion 96B, and inner radial portion 96C of the multi-contoured surface 96. The multi-contour surface 96 facilitates blood expression by creating a pressure gradient that extends radially inwardly toward the opening 101 from the perimeter 100 of the contact ring 95 or cap body 94. According to one embodiment, an anti-slip feature on the contact ring 95 prevents movement of the contact ring relative to the skin surface when the contact ring is pressed into contact with the fingertip. As discussed, the anti-slip feature can comprise a suitable anti-slip material, such as rubber or silicone, affixed to the multi-contoured surface. Alternatively, at least a portion of the multi-contoured surface comprises a roughened contact surface to ensure friction between the contact ring and the skin.
An alternative embodiment of the cap of the present invention is illustrated in
The illustrated contact ring is preferably formed of a deformable, resilient, flexible material that is capable of conforming to the shape of the body region of the user placed in contact therewith. The contact ring can be preferably formed of a rubber material, polyurethane, latex, or other flexible material. The cap body 112 can also be formed of any suitable transparent, translucent, or opaque material, such as clear or transparent plastic, or can include a transparent portion forming a window to the interior of the cap body to enable the user to view the expressed blood. Alternatively, the cap can be formed of a non-transparent material.
The contact ring 114 can be disposed in a rest position,
According to an alternate embodiment, as illustrated in
The contact ring can be preferably formed of rubber material, polyurethane, latex, or other flexible material. The contact ring 134 can be disposed in a rest position,
The cap body 132 can includes a connector for removably and replaceably connecting a proximal end of the cap body 132 to a distal end of the housing 12. According to one practice, the cap 130 can be permanently affixed to the housing 12. Preferably, the cap 130 is removably and replaceably connected to the housing 12.
Since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are to cover all generic and specific features of the invention described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between.
Claims
1. (canceled)
2. The cap of claim 6, wherein the cap body is transparent, translucent, or opaque.
3. The cap body of claim 6, wherein a portion of the cap body is transparent to allow a user to view the blood sample.
4. (canceled)
5. The cap of claim 6, wherein the cap is removably and replaceably connected to the distal end of the housing.
6. A cap for a lancing device for lancing dermal tissue, the lancing device including a housing having a proximal end and a distal end and a lancet mounted within the housing, the lancet being movable along a first axis relative to the housing the cap comprising:
- a cap body having a proximal end and a distal end, the proximal end of the cap body connecting to the distal end of the housing; and
- a contact ring attached to the distal end of the cap body the contact ring including an opening for a portion of the lancet to pass therethrough, the contact ring having a multi-contoured surface oriented generally about a second axis that is distinct from the first axis an configured to increase the pressure on the dermal tissue to facilitate compression of a blood sample after lancing the dermal tissue, wherein the contact ring has a contacting surface having a flat portion extending radially inwardly from a perimeter portion and wherein the multi-contoured surface extends from the flat portion to the opening.
7. (canceled)
8. The cap of claim 6, wherein the contact ring is formed of a flexible, deformable material.
9. The cap of claim 8, wherein the contact ring includes edge portions which extend outwardly from the cap body.
10. The cap of claim 6, wherein the contact ring has a non-transparent color distinct from and in contrast to the color of the dermal tissue.
11. The cap of claim 1 6, wherein the contact ring comprises a separate and discrete component mounted on the cap body.
12. The cap of claim 6, wherein the contact ring is integrally formed with the cap body.
13. (canceled)
14. The cap of claim 6, wherein the multi-contoured surface includes an anti-slip feature.
15. The cap of claim 14, wherein the anti-slip feature comprises a roughened surface on the multi-contoured surface to increase friction between the contact ring and the skin.
16. The cap of claim 14, wherein the anti-slip feature comprises an anti-slip material affixed to the multi-contoured surface.
17. The cap of claim 6, wherein the contact ring is formed of an anti-slip material.
18. (canceled)
19. A cap for a lancing device for lancing dermal tissue, the lancing device including a housing having a proximal end and a distal end and a lancet mounted within the housing, the lancet being movable along a first axis relative to the housing, the cap comprising:
- a cap body having a proximal end and a distal end, the proximal end of the cap body connecting to the distal end of the housing of the lancing device,
- a contact ring attached to the distal end of the cap body, the contact ring including an opening for a portion of the lancet to pass therethrough, and
- a sleeve mounted about the cap body, the sleeve being movable generally along the first axis and relative to the cap body, the sleeve including at least two legs for maintaining contact with the dermal tissue during expression of a blood sample after lancing the dermal tissue.
20. The cap of claim 19, wherein the sleeve is biased toward the distal end of the cap body.
21. The cap of claim 19, wherein the legs are spaced apart to permit a user's fingers in the space therebetween.
22. The cap of claim 19, wherein the legs are constructed from a resilient material such that the legs act to compress the user's finger when positioned therebetween.
23. The cap of claim 19, wherein the legs include an anti-slip feature to prevent movement of the legs relative to the skin.
24. The cap of claim 23, wherein the anti-slip feature comprises a roughened surface to increase friction between the legs and the skin.
25. The cap of claim 23, wherein the anti-slip feature comprises an anti-slip material affixed to a portion of the legs in contact with the skin.
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
Type: Application
Filed: Sep 22, 2008
Publication Date: Mar 19, 2009
Inventor: Piet Moerman (Martens-Latem)
Application Number: 12/234,758
International Classification: A61B 5/151 (20060101);