JPS59203959A - Measuring device for blood clotting time - Google Patents

Abstract

PURPOSE:To permit easy measurement, to improve accuracy of reproduction and to enable measurement of an abnormal specimen as well by storing momentarily the optically detected value of clotting and calculating the time until set % is attained with a satd. value as 100%. CONSTITUTION:When the sample having the same temp. as the temp. of a blood plasma sample is injected into the device by a pipette 8, the time for starting the measurement is set in an arithmetic circuit 12 and at the same time a light shielding cover 4 is closed. The detection and measurement of the clotting by a light source 5, a photodetector 6 and a detecting circuit 10 are started. The measured value is stored momentarily into a storage circuit 13 and when the measured value is satd., the circuit 10 is controlled by the circuit 12 to end the measurement. The circuit 12 calculates the measuring time of each % with the satd. value as 100% and stores the same, etc. again in the circuit 13. The time for the clotting complying with the assigned % from a keyboard 11 is outputted to a CRT14 or recorder. The measurement is easily accomplished by such constitution which performs the automatic measurement and % processing, by which the reproducibility is improved and the measurement of the abnormal specimen is made easy and sure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus capable of measuring blood coagulation time with high reproducibility.

Conventionally, the clotting time of large or animal blood has been measured, and items that contribute to the diagnosis of diseases include prothrombin time (PT) and partial thromboplastin (PTT).
, fibrinogen level (Fbg) or deficiency factor quantification, activated partial thromboplanutin time (APTT)
), Ca re-addition time, etc. These items are determined by which component in the blood is reacted with the reagent added. For example, in the measurement of prothrombin time (PT), it is the time it takes for a white reticular fibrin clot to form when enough tissue trompoplanutin and calcium are added to plasma in blood components after centrifugation. For example, activated partial thromboplastin time (APT)
In measuring T), calcium chloride is added to the plasma collected after centrifugation in addition to a reagent called actin, and the time until a clot forms is measured. That is, plasma centrifuged from blood is stored in a refrigerator, and 0.1 mn of actin heated for 1 minute in a 37°C water bath is added to a test tube containing 0.1 mn of this plasma.
Warm at 7°C for 2 minutes, then add 0°02M Qa, (:, 120.1mβ) that had been placed in a 37°C water bath
Blow in strongly and press the stopwatch at the same time. The test tube is then placed in a 37°C water bath and heated for 25 seconds, after which the test tube is removed and observed, and the stopwatch is stopped when clot formation occurs to measure the clotting time.

The above method is a method of direct measurement by hand, and is generally referred to as a manual method. This method requires considerable skill on the part of the examiner and cannot be easily measured by anyone. With the advent of problem behavior analyzers, clotting time has come to be measured automatically. This method detects clots using optical means, but compared to manual methods, it detects clots locally, and depending on the measurement conditions, there are large gaps and gaps, and poor reproducibility. There was a drawback. Furthermore, due to the configuration of automated analyzers, there is a problem in how to define the so-called "clotting time." In general, a predetermined optical level is set in optical measurement, and when that level is crossed, The method of using the time point as the clotting time, or the inflection point (
There is a method of differentiating the change curve with respect to time and using the peak point as the coagulation time.

In the former level detection method, how the level is set -
Therefore, in the case of an abnormal sample, it may not be possible to reach that level, and it was usually dismissed as unmeasurable.

That is, in FIGS. 1 and 2, when the level is set to L3, the curve of the abnormal sample does not reach level /L/L3, so the measurement continues continuously. On the other hand, as shown in Figures 3 and 4, even with the latter method of determining the inflection point, it is difficult to detect the inflection point in abnormal samples, as shown in Figure 4. Even if a measurement error occurred, there was a risk that the machine would mistakenly interpret it as an inflection point. The above measurement results do not necessarily agree with the measurement results obtained by manual methods, so it was necessary to correct the measurement values in comparison with conventional methods in order to use them for diagnosis.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a blood coagulation time measuring device that facilitates the measurement of abnormal samples, etc., for which the coagulation time has conventionally been difficult to measure, and has high reproducibility. It is.

Hereinafter, the configuration of the present invention will be explained based on embodiments shown in the drawings. FIG. 5 is an explanatory diagram showing the configuration of the present invention, and FIGS. 6 and 7 are explanatory diagrams showing the measurement principle. Reference numeral 1 denotes a detection block, which includes a storage section 3 for storing a sample container 2 containing a plasma sample, a light-shielding lid 4 for opening and closing this storage section 3, and a detection block provided adjacent to the side of the sample container 2. light source 5
It also has a light receiving element 6 and a temperature control element 7 that keeps the sample in the sample container 2 at a predetermined temperature. Reference numeral 8 denotes a pipette with a switch, which adds a reagent maintained at a predetermined temperature to the sample container 2, and is turned on at the time of addition to issue a measurement start signal. A detection circuit 10 for detecting a signal from the detection block 1 is connected to the light receiving element 6 . 11
is a keyboard switch for selecting measurement items and inputting various conditions; this keyboard switch 11. Pipette with switch 8, detection circuit 10 and temperature control element 7
An arithmetic circuit 12 is connected to the arithmetic circuit 12, and a memory circuit 13, a display device 14, and a recording device 15 are connected to the arithmetic circuit 12. 16 is a temperature control circuit, and 17 is a reagent container.

In the apparatus configured as described above, when a similarly temperature-controlled reagent is added to a plasma sample previously maintained at a predetermined temperature using a pipette with a switch 8, the measurement start time is determined by the arithmetic circuit 12. light-shielding lid 4
When closed, measurement is started, and the measured values are sent from the detection circuit 10 to the arithmetic circuit 12 and stored in the memory circuit 13 every moment. These measurements can also be monitored through display device 14. When the curve changes and takes a constant value and reaches a saturated state, the arithmetic circuit 12 issues a command to the detection circuit 10 to end the measurement, and at the same time, the display device 14 indicates that the measurement has ended. The above final measured value (saturation value) is set as 100%, and a calculation is performed in the calculation circuit 12, and the calculation result is stored again in the remaining space of the storage circuit 13. 20 by using the keyboard switch 11 in advance.
%, 50%, 80%, etc., are set to be printed or displayed as a result, and each value is calculated by the arithmetic circuit 12. For example, for a normal sample as shown in Figure 6 or an abnormal sample as shown in Figure 7, it is easy to calculate 20%, 50%, 80%, etc. The values are in good agreement with the clotting times measured by conventional manual techniques.

Calculating the measurement result using the above percentage value always outputs a constant value regardless of errors in the device itself, such as lamp deterioration, deterioration of the light receiving part, or improper adjustment.
Very effective.

Since the present invention is configured as described above, the end point of the conventional coagulation time is the detection of the level or inflection point, but it can be expressed as a percentage, thereby improving the correlation with the conventional method. Of course, the reproducibility of measurements is dramatically improved. Furthermore, errors due to device drift are reduced, and abnormal samples can be easily measured.

[Brief explanation of drawings]

FIGS. 1 and 2 are graphs showing an example of a conventional level detection method, FIGS. 3 and 4 are graphs showing an example of a conventional method for determining an inflection point, and FIG. 5 is a graph showing an example of a conventional method for determining an inflection point. An explanatory diagram showing an example of the configuration, and FIGS. 6 and 7 are graphs showing the measurement principle. DESCRIPTION OF SYMBOLS 1... Detection block, 2... Sample container, 3... Storage part, 4... Light shielding lid, 5... Light source, 6... Light receiving element, 7... Temperature control element, 8. ...Pipette with switch, 10...Detection circuit, 11...Keyboard switch, 12...Arithmetic circuit 1.3...Memory circuit, 14.
...Display device, 15...Recording device, 16...Temperature control circuit, 17...Reagent container Patent applicant Toa Medical Electronics Co., Ltd. Agent Patent attorney Shiodegu -- ρzo... (N" Shizuku° 1.・ Figure 7 Figure 7 Procedural amendment (method) 1. Indication of the case 1982 Patent Application No. 78651 2. Title of the invention Blood coagulation time measuring device 3. Person making the amendment Relationship to the case Patent application Address: 7 Rigana, 6-6-17 Daikaidori, Hyogo-ku, Kobe City.
Toa I Yodenono-I (Name) Toa Medical Electronics Co., Ltd. 4, Agent

Claims (1)

[Claims] 1. A storage section that stores a sample container containing a plasma sample, a light-shielding lid that opens and closes this storage section, a light source and a light-receiving element provided adjacent to the side of the sample container, and a sample container that keeps the sample in the sample container at a predetermined temperature. a detection block having a temperature control element that maintains the temperature at
A pipette with a switch that adds reagents kept at a predetermined temperature to a sample container and that turns on when added and issues a measurement start signal, a detection circuit that detects signals from a detection block, and a selection of measurement items and various conditions. It consists of a keyboard switch for inputting information, an arithmetic circuit connected to a pipette with a switch, a keyboard switch, a detection circuit, and a temperature control element, a memory circuit, a display device, and a recording device connected to the arithmetic circuit. When the lid is closed, measurement starts, and the measured values are sent from the detection circuit to the calculation circuit and stored in the memory circuit every moment.The curve changes and takes a constant value, and when it reaches saturation, the calculation circuit sends a command to the detection circuit to end the measurement, the saturation value is set to 100%, calculation is performed in the calculation circuit, and υ is set in advance by the keyboard switch.
A blood coagulation time measuring device characterized in that the coagulation time is defined as the period until a measured value of a predetermined percentage is obtained.