JP3604822B2 - Body fluid analyzer - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a body fluid analyzer capable of analyzing a substance to be detected contained in a body fluid such as a blood glucose level, and more particularly to a body fluid analyzer capable of automatically and continuously performing a series of steps.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, when measuring a blood glucose level or the like, a finger, upper arm, abdomen, buttocks, etc. were scratched using a puncture device (lancet), blood droplets were squeezed out therefrom, taken out of a packaging material, and attached to a sensor. This has been done by attaching the blood drop to the electrode.
However, it is very troublesome to squeeze out the necessary amount of blood droplets for measurement, and if the puncture device and sensor are separated, there are many operations required by the measurer in performing a series of processes, There is a problem that the measurement is complicated.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to provide a convenient body fluid analyzer capable of automatically, continuously, and effectively performing a series of steps required for measurement.
[0004]
[Means for Solving the Problems]
In view of the above problems, as a result of intensive research, the present inventors have obtained information on the puncture means, the compression band (cuff) for discharging bodily fluid from the punctured finger and the pressurizing means, and information on the discharged bodily fluid into an electric signal. A unit for converting, a means for determining a measured value based on the electric signal, a display for displaying the determined measured value, and the like are housed in one device, and a series of steps required for the measurement are automatically and continuously controlled by a computer. It has been found that the analysis of body fluid can be performed easily and quickly.
Further, the distance between the puncture blade or the puncture needle in the puncture means and the electrode in the electric signal conversion means was considered as follows.
[0005]
The volume of blood required for one measurement is generally 5 to 30 μl. A drop of blood (blood drop) squeezed out from the punctured skin forms a substantially hemisphere. The diameter of this hemisphere is calculated to be 2.6 to 4.9 mm when calculated from the blood volume. The same was true for the measurement results. Therefore, by setting the distance between the puncture blade or puncture needle and the electrode within 5 mm, the discharged bodily fluid can be surely brought into contact with the electrode. The present inventors have also newly found the above and completed the present invention.
[0006]
That is, the present invention provides a puncture device for puncturing a finger with a puncture blade or a puncture needle, a compression band for compressing the finger, a pressurizing unit for supplying air to the compression band, and air in the compression band. A body fluid having an exhaust means for exhausting, a means for converting information relating to a body fluid discharged from a finger into an electric signal by an electrode, a means for determining a measured value based on the electric signal, and a display for displaying the determined measured value An analyzer, wherein a distance between the puncture blade or puncture needle and the electrode is within 5 mm.
Further, the present invention is a body fluid analyzer in which a pressure sensor for detecting a pressure of a cuff is further added to the above body fluid analyzer.
[0007]
[Action]
Puncturing means for puncturing a finger with a puncturing blade or a puncturing needle, a cuff for pressing the finger, a pressurizing means for supplying air to the cuff, an exhaust means for exhausting air from the cuff, According to the body fluid analyzer of the present invention, which has means for converting information about the humored body fluid into an electric signal by the electrode, means for determining a measured value based on the electric signal, and a display for displaying the determined measured value. After piercing the finger, the finger is pressed with a pressurized cuff to drain the body fluid, and after draining, the cuff is loosened by exhausting and the finger is opened, and necessary information from the obtained body fluid is converted into an electric signal. Since the measured value can be changed and displayed on the display, a series of steps required for the measurement can be performed automatically and continuously, and the analysis of the bodily fluid can be performed simply and quickly.
[0008]
In the body fluid analyzer of the present invention, the distance between the puncture blade or the puncture needle and the electrode is specified to be 5 mm or less. By limiting the distance between the two as described above, the amount of bodily fluid discharged by puncture can be reduced. The measured body fluid can be surely brought into contact with the electrode while keeping the necessary minimum, and the measurement can be performed effectively. Further, the design of the apparatus can be effectively performed.
By adding a pressure sensor that detects the pressure of the cuff to the body fluid analyzer, the upper limit of the pressure of the cuff can be determined regardless of the thickness of the finger of the measurer, and gives the measurer an excessive feeling of pressure. An appropriate amount of bodily fluid can be squeezed out of the finger without the need.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
Here, the body fluid in the present invention refers to a liquid that can be discharged from a living body by puncturing, such as blood or intercellular exudate.
FIG. 1 shows a perspective view of a body fluid analyzer according to an example of the present invention. The body fluid analyzer 1 has a rectangular parallelepiped casing 11, and the casing 11 is provided with a tightening unit 2, a puncturing unit 3, a display 4, a main switch 51, and a puncturing switch 52. .
[0010]
The tightening portion 2 has a cylindrical shape so that a finger can be inserted therein, and a cuff (compression band) 21 for pressing the finger is provided inside the tightening portion 2. The cuff 21 can press and release a finger by using the injection and exhaust of air by a cuff driving device (not shown). The cuff driving device has a sensor (pressure sensor) for detecting the pressure of the cuff 21, a solenoid valve, a pump, and a leak valve, and these are communicated with the cuff 21 through a rubber tube. The cuff driving device is controlled by a computer (not shown) provided inside the body fluid analyzer 1.
[0011]
The puncture part 3 has a sleeve 6 and a plate-shaped base 7 housed in the sleeve 6 as shown in FIG. A puncturing blade 71 is provided on one side of the base 7 so as to be able to move forward and backward (see FIGS. 3A and 3B), and an electrode tip 72 is provided on the other side. Electrode leads 73a and 73b are provided so as to be connected to the terminals of the electrode chip 72 (see FIG. 3 (c)). Further, leaf springs 74 are provided on both front sides of the base 7, and the protruding puncture blade 71 can be retracted to the initial position. FIG. 3D is a perspective view of the base 7 and the puncture blade 71 as viewed from the rear.
[0012]
The puncture blade 71 is preferably made of stainless steel in consideration of hygiene safety, and a commercially available puncture blade 71 such as Blood Lancets manufactured by Feather Safety Razor can be used. In addition, although the puncture blade is used in the present embodiment, the present invention is not limited to this, and may be anything as long as it can injure the skin and discharge body fluids, For example, it may be needle-shaped (puncture needle).
[0013]
The electrode tip 72 is provided with electrodes (a working electrode and a reference electrode), and one of the electrodes is coated with an enzyme ink (not shown). Various types of enzyme inks can be selected according to the substance to be detected in the body fluid. For example, when measuring a blood glucose level, an ink composition containing glucose oxidase or the like can be used.
[0014]
FIG. 4 shows a top view of the base 7, the puncturing blade 71 and the electrode tip 72 (in a state where the puncturing blade 71 is protruded). In this embodiment, the puncture blade 71 and the electrode tip 72 are provided in parallel, but the distance (L) between the puncture blade 71 and the electrode provided on the electrode tip 72 needs to be within 5 mm. . The “distance between the puncture blade and the electrode” as used herein refers to an extension including the tip of the puncture blade (a portion for puncturing the skin) and a tip of the electrode in a parallel relationship with the extension. (The part where the discharged body fluid comes into contact first.) The same applies when a puncture needle is used.
[0015]
By defining the distance between the puncture blade 71 and the electrode to be within 5 mm, a minimum necessary amount of bodily fluid can be surely brought into contact with the electrode. This is because the volume of the body fluid required for one measurement is generally 5 to 30 μl, and the diameter of the hemisphere formed by the discharged body fluid is 2.6 to 4.9 mm when calculated from the volume of the body fluid. It is. However, since the punctured portion is usually the center of the hemisphere formed by the bodily fluid, the distance between the puncture blade 71 and the electrode is more preferably within 2.5 mm.
If the sleeve 6 containing the base 7 having the puncture blade 71 and the electrode tip 72 is made into a cartridge type that can be detached from the body fluid analyzer 1, they can be disposable, which is very advantageous for hygiene. It becomes.
[0016]
The puncture blade 71 is advanced (see FIG. 2) by driving a puncture blade driving device (in this embodiment, a solenoid) 9 via the arm member 8. The solenoid 9 is driven by turning on the puncture switch 52. The tip portion of the puncturing blade 71 that has been advanced projects from the base 7 and reaches a position ahead of the electrode tip 72. The amount of protrusion of the puncture blade 71 from the electrode tip 72 is such that the finger can be punctured and drained while the finger is attached to the body fluid analyzer 1, and the discharged body fluid comes into contact with the electrode tip 72. What is necessary is just to set so that it may be obtained. Specifically, it is preferably from 100 to 2000 μm, particularly preferably 750 μm. The protruding puncture blade 71 is retracted to the initial position by the action of the leaf spring 74 provided on the base 7. In this embodiment, the solenoid is used as a method for driving the puncture blade. However, the present invention is not limited to this, and the puncture blade can be driven by various methods.
[0017]
FIG. 5 is a block diagram showing an example of a circuit configuration of the body fluid analyzer.
In this body fluid analyzer, the cuff 21 communicates with a pressure sensor, an electromagnetic valve, a pump, and a leak valve by a rubber tube, and these constitute a pneumatic system. The operation of each member in the body fluid analyzer is controlled by a computer. The computer has a function to turn on / off a solenoid valve, a leak valve and a pump, a function to capture air pressure data detected by a pressure sensor, a function to operate a solenoid, a function to capture an electric signal from an electrode, and a function to calculate an electric signal. It has a function of determining a measured value and a function of outputting the measured value to a display.
[0018]
This computer is initialized when the main switch 51 is turned on, drives the solenoid 9 when the puncture switch 52 is turned on, and is programmed to drive the pump after a predetermined time. In addition, the pump may be turned off and the solenoid valve and the leak valve may be opened by taking in information that the pressure of the cuff 21 or the body fluid that has been detected by the pressure sensor has come into contact with the electrode, or after a predetermined time has elapsed since the pump was turned on. Command. The electric signals from the electrodes are also taken into the computer, and the measured values determined by the computer are output to the display 4.
[0019]
Note that this circuit configuration is merely an example, and a pressure sensor may not be necessary in some cases.
An example of the detailed operation of the body fluid analyzer in FIG. 1 will be described with reference to the flowchart shown in FIG.
Before starting the measurement, the measurer inserts a finger into the cuff 21. The finger may be any finger, or may be a finger on either the left or right hand. When the main switch 51 is turned on, the system is initialized such as clearing the memories in the computer.
[0020]
Next, the measurer turns on puncture switch 52. When the puncture switch 52 is turned on, the solenoid 9 is driven, and the puncture blade 71 projects from the base 7 via the arm member 8 (step 1). The protruding puncture blade 71 returns to its original position by the action of the leaf spring 74 after damaging the skin of the fingertip. After the puncture blade has protruded, the pump is driven (step 2), and the cuff 21 is pressurized. The cuff 21 compresses a finger and squeezes body fluid from the damaged skin.
[0021]
There are three methods for determining whether to turn off the pump. First, when the apparent blood pressure reaches a predetermined value (P) due to, for example, the pressure of the cuff, the determination is YES (FIG. 6: step 3). Note that the apparent blood pressure refers to a transient blood pressure value displayed from the pressure sensor in the process of pressing the finger with the cuff. That is, an apparent blood pressure that directly reflects the cuff pressure can be detected by the pressure sensor. The value of P is desirably 120 mmHg or more, and about 180 mmHg can obtain the most appropriate amount of liquid. According to the first method, the upper limit of the cuff pressure can be determined regardless of the thickness of the finger of the measurer, and the body fluid can be squeezed out without giving the measurer an excessive feeling of pressure.
[0022]
Second, when a predetermined time (T) has elapsed since the pump was turned on, the determination is YES (FIG. 7: step 3 '). The value of T is preferably about 5 to 60 seconds, and about 20 seconds can obtain the most appropriate amount of liquid.
Third, when the squeezed body fluid comes into contact with the electrode, the determination is YES (FIG. 8: Step 3 ″). According to the third method, a necessary and sufficient amount of body fluid can be secured and excess The finger is not unduly pressed by the pressure, and the pressure sensor is not required when the second method and the third method are applied in this step.
[0023]
When the drive of the pump is stopped according to the determination by any one of the first to third methods (FIG. 6: step 4), the solenoid valve and the leak valve are opened immediately, and the air in the cuff is quickly exhausted (step 5). ). One valve may be used, but by using the electromagnetic valve and the leak valve together, the air in the cuff can be quickly exhausted, and the finger of the measurer can be released from the compressed state.
[0024]
The squeezed body fluid comes into contact with the electrode on the electrode tip 72, and information on the body fluid is sent to the computer as an electric signal to start the calculation (step 6). When the time t has elapsed from the start of the calculation (step 7), the calculation is terminated (step 8). Since a certain time is required for the measured value to stabilize, the value of t greatly depends on the performance of the electrode, but generally requires about 5 to 60 seconds. When the measured value is determined by the calculation by the computer, the measured value is displayed on the display 4 (step 9).
[0025]
According to the body fluid analyzer of the present invention described above, a series of operation steps can be reduced, and the inspection can be completed very easily. In addition, the apparatus includes a puncturing means, a pressurizing means, a means for converting information about a bodily fluid into an electric signal, a means for determining a measured value, and a display for displaying the measured value. Since the distance is defined, the general user does not need skill, and can measure quickly, reliably, and effectively. Furthermore, the body fluid analyzer of the present invention can analyze not only the blood sugar level but also various substances in the body fluid by changing the type of the enzyme ink used.
[0026]
Although the present invention has been described in detail with reference to the drawings, the present invention is not limited thereto, and various modifications can be made without departing from the spirit of the present invention. For example, by making the display part rotatable with respect to the apparatus main body, the display can be oriented in a desired direction, and measurement can be easily performed. Further, the present invention is not limited to a finger, and may be applied to a device for a wrist, an arm or the like. Furthermore, it is also possible to provide an audio guide for the blind and to change the system to a series of systems until the measurement result is heard with a single switch.
[0027]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the apparatus of this invention, a series of processes required for a measurement can be performed automatically and continuously, and the analysis of a bodily fluid can be performed effectively, simply, and quickly.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a body fluid analyzer of the present invention.
FIG. 2 is a view showing a sleeve, a base, a puncturing blade, and a puncturing blade driving device (solenoid) in the body fluid analyzer of the present invention.
FIG. 3 is a view showing a base, a puncture blade and an electrode tip in the body fluid analyzer of the present invention. (A) is a view as seen from the puncture blade side, (b) is a view showing a state where the puncture blade is projected, (c) is a view as seen from the electrode tip installation side, and (d) is a rear view. FIG.
FIG. 4 is a view of the base, the puncture blade, and the electrode tip in the body fluid analyzer of the present invention as viewed from above.
FIG. 5 is a block diagram showing an example of a circuit configuration of the body fluid analyzer of the present invention.
FIG. 6 is a flowchart showing an example of the operation of the body fluid analyzer in FIG. 1;
FIG. 7 is a diagram showing another example of step 3 in the flowchart of FIG. 6;
FIG. 8 is a diagram showing another example of step 3 in the flowchart of FIG. 6;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Body fluid analyzer 11 ... Casing 2 ... Tightening part 21 ... Cuff 3 ... Puncture part 4 ... Display 51 ... Main switch 52 ... Puncture switch 6 ... Sleeve 7 ... Base 71 ... Puncture blade 72 ... Electrode tips 73a, 73b ... Electrode Lead 74: leaf spring 8: arm member 9: solenoid

Claims (2)

Puncture means for puncturing a finger with a puncture blade or a puncture needle, a compression band for compressing the finger, pressurizing means for supplying air to the compression band, and exhaust means for exhausting air from the compression band, A pressure sensor for detecting the pressure of the cuff, a means for converting information on body fluid discharged from a finger into an electric signal by an electrode, a means for determining a measured value based on the electric signal, and displaying the determined measured value A body fluid analyzer having a display, wherein a distance between the puncture blade or puncture needle and the electrode is within 5 mm. Puncture means for puncturing a finger with a puncture blade or a puncture needle, a compression band for compressing the finger, pressurizing means for supplying air to the compression band, and exhaust means for exhausting air from the compression band, Means for converting information about the bodily fluid discharged from the finger into an electrical signal by an electrode, means for determining a measured value by the electrical signal, and a body fluid analyzer having a display for displaying the determined measured value, A body fluid analyzer, wherein a distance between the puncture blade or puncture needle and the electrode is within 5 mm.

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