JPS5913947A - Apparatus for measuring hematocrit - Google Patents

Abstract

PURPOSE:To measure a hemtocrit value rapidly and automatically, by determining the specific volume of blood cell part composing the blood, i.e., the hematocrit value with the use of the solution conductivity of the blood, giving attention to the face that the solution conductivity of the blood changes with the specific volume of the blood cell part. CONSTITUTION:Electrode plates 4 of a probe 2 are immersed in a vessel 1 in which a blood sample collected from a patient is placd. In case when an alternate potential from an alternate current source 6 is impressed via a reference resistor 7, a potential reduction proportinal to the solution conductivity between the electrode plates 4 occurs at the terminal of the reference resistor 7. The potential reduction is expressed in terms of a hematocrit value by an amplifier 8, is indicated by an indicator 9, and is recorded by a recorder 10. Hematocrit values obtained from the conductivity of the blood by the present invention are very highly coincident with those by microhematocrit method.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hematocrit measuring device that can electrically measure the volume ratio occupied by blood cells contained in blood.

Conventionally, hematocrit has been measured using the microhematocrit method, which involves injecting blood collected from a patient into a Wintrope tube or capillary tube, centrifuging it in a centrifuge, and then measuring the length of the blood cell layer interface. Ta. However, with this method, it takes several minutes to more than 10 minutes to obtain measurement results, so when measuring a large number of samples such as in a mass medical examination, it requires a great deal of time and effort. There have been problems such as the difficulty of assessing the patient's condition from moment to moment during emergencies such as surgeries.

SUMMARY OF THE INVENTION In view of these problems, it is an object of the present invention to provide a hematocrit measuring device that can automatically measure hematocrit in a short time.

In other words, the present invention is characterized by focusing on the fact that the solution conductivity of blood changes depending on the volume of the surface spheres constituting the blood, and by calculating the volume of blood cells, that is, the hematocrit value, from the solution conductivity of blood. Hereinafter, details of the present invention will be explained based on illustrated embodiments.

FIG. 1 is a block diagram showing one embodiment of the present invention, in which a probe 2 is immersed in blood contained in a sample container 1.
is composed of a base 6 and two opposing electrode plates 4.4 fixed to the base at a predetermined distance, and these two electrode plates 4.4 have a An alternating current power source 6 is connected via a standard resistor 7 to an apparatus main body 5 for converting and displaying hematocrit values, and a display 9 and a recorder 10 are further connected to this resistor 7 via an amplifier 8.

Next, the operation of the apparatus configured as described above will be explained. When the electrode plate 4.4 of the probe 2 is immersed in the sample container 1 containing blood collected from a patient and an alternating voltage from the AC power supply 6 is applied via the standard resistor 7, the terminal of the standard resistor 7 is connected to the electrode plate 4.4. A positive pressure drop fCC occurs in proportion to the solution conductivity between 4 and 4. This voltage drop is converted into a hematocrit value by an amplifier 8 and recorded on a display 9 and a recorder 10.

FIG. 2 is a graph showing the correlation between the hemadcrit values of 37 blood samples measured by the above-mentioned device and those measured by the microhemadcrit method of the same samples. It can be seen that the hemadcrit value of the invented device has very high agreement with that obtained by the microhemadcrit method.

The embodiment described above is very effective for automatically measuring the hematocrit value of a large number of blood samples collected through mass medical examinations, etc., but the second embodiment of the present invention shown in FIG. 1 is a measurement cell 1 installed in the middle of a blood transport pipe 12 connected to an artificial heart-lung machine 11 used in heart surgery.
3, the electrode plate of the probe 2 is immersed in the measurement cell 1.
By monitoring the patient's blood flowing through the device 3 with the device body 5, the patient's hematocrit value can be measured moment by moment.

As described above, according to the present invention, the hematocrit value is measured from the conductivity of the blood by immersing the electrode plates arranged oppositely into the blood, so that the measurement results can be obtained automatically and quickly. Not only is it possible to obtain results in a short amount of time, but it also eliminates the need for capillary injection of blood or centrifugation treatment, which greatly simplifies the measurement operation. Furthermore, measurements can be made in an extremely short time by simply immersing two small electrode plates arranged opposite each other in blood, making it possible to measure blood parameters online by placing them in parallel with ion concentration measurement electrodes, etc. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus showing an embodiment of the present invention;
Fig. 2 is a correlation diagram showing the consistency between the hematocrit measurement values according to the present invention and the measurement values by the microhematocrit method, and Fig. 3 is a block diagram showing another embodiment in which the device of the present invention is applied to a heart-lung machine. It is a diagram. 1... Sample container 2... Probe 4... Electrode plate 5... Apparatus body 11... Heart-lung machine 12...
Blood Transport Pipe Applicant: Shimadzu Corporation Representative Patent Attorney: Harutoshi Nishikawa
Uhiko Kimura Figure 1, 3rd concave

Claims (1)

[Claims] A hematocrit measuring device comprising two electrode plates disposed opposite to each other in blood, and means for deriving a value corresponding to hematocrit from the electrical conductivity between the electrode plates.