Surgery – Instruments – Cutting – puncturing or piercing
Reexamination Certificate
1999-01-19
2001-04-03
Buiz, Michael (Department: 3731)
Surgery
Instruments
Cutting, puncturing or piercing
C606S181000
Reexamination Certificate
active
06210420
ABSTRACT:
FIELD OF THE INVENTION
The present invention is related to techniques for lancing skin tissue with a lancet and drawing blood from it and more particularly to apparatuses and methods for lancing skin tissue to obtain an adequate sample with less pain.
BACKGROUND
The analysis and quantification of blood components is an important diagnostic tool for better understanding the physical condition of a patient. Since adequate noninvasive blood analysis technology is not currently available, blood samples still need to be obtained and analyzed by invasive methods from a great number of patients every day. A well known example of such needs is self monitoring of glucose levels by a diabetic individual, often performed in the home of the individual. To obtain a blood sample it is necessary to puncture the skin with a sharp object such as a lancet at a region well supplied with blood vessels, for example, the fingertip. For lancing, a lancet launcher is first loaded with a lancet and cocked by pulling or rotating the cap on the launcher. The tip of the launcher is then pressed against the skin and a button is pressed to launch the lancet to strike the skin.
Currently available lancet launchers are typically pen-shaped devices. The lancet is held in a cylindrical piston which is propelled by a spring mechanism. On cocking, the spring serves to store the energy required to propel the piston forward at the skin. The propulsion of the lancet causes the lancet to impact against and puncture the skin, causing a wound large enough for sampling blood.
Such blood sampling is often painful and inconvenient. As a result, many patients tend to not sample blood as frequently as suggested by the health professionals to monitor the physiological functions adequately. Moreover, for fear of pain in blood sampling, many patients fail to use the lancet launchers properly. Such improper use results in inadequate blood volume being collected and requires repeating the lancing procedure, causing more pain and multiple wounds.
What is needed is a lancet launcher for sampling blood that can be used for sampling blood efficiently, so as to minimize pain to encourage a patient to follow a routine for sampling blood as directed by health professionals.
SUMMARY
In the present invention, the sampling of blood from body tissue is facilitated by applying a negative pressure to the body tissue before and while a lancet is launched to inflict a bleeding wound in the body tissue. This negative pressure is mechanically transmitted internally through substantially the body of the lancet device. In this way, there is no cumbersome suction source attached to the front part of the lancet device to hinder convenient application of the lancet device to the body tissue.
In one aspect, the present invention provides an apparatus having a lancet for sampling blood from body tissue. An embodiment of this apparatus includes a lancet, a housing, and a driver that drives the lancet for lancing. The lancing of the body tissue by the lancet results in a wound for bleeding. The housing is operatively connected to the lancet and shields it before lancing. The housing has a head for contacting the body tissue in an air-tight manner against vacuuming (i.e., suction) forces and having a channel in which the air pressure can be reduced before the lancet is driven to lance the body tissue. As an example, a piston can be included in the channel for air-tight sliding movement against the channel wall along the housing. Mechanical energy is transmitted via the piston from near the rear of the lancet device to near the head to result in reduced air pressure. In one embodiment, a rearward movement of piston in the channel can cause the air pressure in the channel near the head to be reduced before lancing. In another embodiment, withdrawing air through a bore in the piston from the front to the back of the piston while the front of the channel is sealed by the body tissue allows the piston to slide forward to drive the lancet toward the body tissue as the air pressure is reduced at where the lancet device contacts the body tissue.
Currently, finger-prick devices do not provide enough blood for certain tests that require larger volumes. Often large and multiple wounds are required. For example, some patients, such as infants, have veins that are difficult to locate for sampling through an intravenous needle. In these patients the device of the present invention can provide larger volumes for a smaller puncture wound. Also, using the present apparatus, by reducing the environmental pressure on the body tissue to increase its blood perfusion, the depth of penetration by the lancet into the body tissue can be reduced to provide an adequate blood sample. With a smaller penetration depth, the trauma and pain of overpenetration is avoided. Such reduction of discomfort and tissue damage can significantly improve the willingness of patients to comply with, for example, a blood sampling routine. The compact designs of the present lancet devices allow the lancet devices to be conveniently maneuvered without clustering around the lancing location on the body tissue. This is significant for the precise positioning of the lancet device on a desired location on the skin and one-handed operation by a patient who may have lost substantial dexterity due to a chronic illness.
REFERENCES:
patent: 4230118 (1980-10-01), Holman et al.
patent: 4535769 (1985-08-01), Burns
patent: 4653513 (1987-03-01), Dombrowski
patent: 4924879 (1990-05-01), O'Brien
patent: 5314442 (1994-05-01), Morita
patent: 5318584 (1994-06-01), Lange et al.
patent: 5395387 (1995-03-01), Burns
patent: 5666966 (1997-09-01), Horie et al.
patent: 5680872 (1997-10-01), Sesekura et al.
patent: 5827181 (1998-10-01), Dias et al.
patent: 5857983 (1999-01-01), Douglas et al.
patent: 5873887 (1999-02-01), King et al.
patent: WO 9637148 (1996-11-01), None
patent: WO 98/24366 (1998-06-01), None
Softclix®, “Lancet Device from the Makers of Accu-Chek® Systems”, (Product), PP. (3 pages), Becton Dickinson & Co., Franklin Lakes, New Jersey.
One Touch® Profile™ “Diabetes Tracking System”, Owner's Booklet, (Product), PP.31-33, LifeScan Inc.
Glucometer Elite®, “Diabetes Care System”, User's Guide, (Product), PP. (3 pages), Miles Inc. Elkhart, IN.
Dias J. Fleming
Mauze Ganapati R
Agilent Technologie,s Inc.
Buiz Michael
Ngo Lien
LandOfFree
Apparatus and method for efficient blood sampling with lancet does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for efficient blood sampling with lancet, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for efficient blood sampling with lancet will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2507591