Surgery – Instruments – Cutting – puncturing or piercing
Patent
1995-10-18
1997-04-29
Buiz, Michael
Surgery
Instruments
Cutting, puncturing or piercing
128770, A61B 500
Patent
active
056244584
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to lancets and blood sampling devices.
2. Prior Art
In medical laboratories, doctors' offices, and the home, there is a frequent need to draw small amounts of blood for diagnostic purposes. Usually blood samples are drawn from the finger, earlobe or another easily accessible body part of the patient. Traditionally, this is done by cleaning the surface of the patient's finger and pricking it with a lancet. Drops of blood are collected in a tube or smeared on a microscope slide for further processing.
The medical personnel or others involved in taking the sample must assure the lancet needle penetrates to an appropriate depth, both to generate enough blood sample and to avoid excessive pain or an unnecessarily large wound. It is also important to keep the lancet from pricking the finger a second time to avoid uncontrolled sampling. Additional requirements are to avoid contaminating any surface of the lancet with blood, and to prevent infection of medical personnel by blood contact. In particular, since the discovery of human immunodeficiency virus (HIV or the AIDS virus), the need to avoid contact with blood samples and lancets has become acute.
Prior lancet devices have several drawbacks. Many lancets use springs to propel the lancet tip, or a needle, into the finger of the patient. These devices do not provide precise control over the depth of penetration of the lancet. Also, many prior lancet devices do not provide for automatic retraction of the lancet tip. Instead, the user must manually retract or cover the tip to prevent re-use. Further, most prior lancet devices require separate sterile packaging to prevent contamination of the lancet tip before it is used. Examples of prior devices having these disadvantages are found in U.S. Pat. Nos. 4,539,988, 4,624,253, and 5,074,872.
This invention avoids these drawbacks of the prior art and achieves the goals described above. The invention also helps prevent infection by blood-borne pathogens, such as the AIDS virus. The invention provides a blood sampling device which is reliable, hygienic, provides an optimum prick depth, and prevents re-use, while having low production costs.
SUMMARY OF THE INVENTION
A blood sampling system or lancet device comprises a piercing device in a closed housing. The housing comprises a perforable wall opposite the piercing device; the perforable wall is perforated by the piercing device at the moment of sampling. The piercing device is held in a cavity or recess on a platform formed integrally with a compressible, flexible upper wall of the device. This flexible upper wall of the housing permits vertical movement of the assembled piercing device; pressing on the flexible wall drives the piercing device through the perforable wall and into the patient's finger or other body part.
The flexible wall eliminates the need for a spring to retract the lancet. After sampling, the flexible wall itself retracts the lancet through spring tension developed in the material from which the wall is made.
The invention also includes means to control the depth of puncture by the piercing device. In one embodiment, the depth control means is a collar or rim integrally formed with the outside of the perforable wall of the housing. The collar defines a predetermined area; the center of the area is the piercing point at which the piercing device perforates the perforable wall. Pressure on the collar forces the skin to assume a tight, hemispherical shape, ensuring accurate puncture depth.
In one embodiment, the blood sampling device has a safety or stop mechanism which blocks repeated vertical movement of the piercing device by immobilizing the lancet inside the housing.
Other aspects of the invention are explained in the detailed description below and in the attached drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an exploded side elevation of one embodiment of a lancet device of the invention, shown in partial cross-section;
FIG. 2 is a section view of th
REFERENCES:
patent: 4869249 (1989-09-01), Crossman et al.
patent: 5026388 (1991-06-01), Ingalz
patent: 5054499 (1991-10-01), Swierczek
patent: 5201324 (1993-04-01), Swierczek
patent: 5231993 (1993-08-01), Haber et al.
patent: 5318581 (1994-06-01), Sunmo
patent: 5402798 (1995-04-01), Swierczek
Buiz Michael
Lewis William
Varro Anne Marie
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