JPH04288129A - Blood viscosity observing apparatus - Google Patents

Abstract

PURPOSE:To judge viscosity of blood accurately and non-invasively requiring no skill by obtaining a blood viscosity ovservation data which is quantified as time difference between a detection output signal with a first pressure sensor for detecting a pulse wave of an artery on the side of a heat and a detection output signal with a second pressure sensor for detecting the pulse wave of the artery on the peripheral side. CONSTITUTION:First and second pressure sensors 1 and 2 are pressed by a pressing means to press an artery and a pressing force is controlled with a pressing control section 8 to a state of restricting the passage of a blood stream from which a detection signal of a specified level is obtained with the second pressure sensor 2 for detecting a pulse wave of the artery on the peripheral side. In the state of restricting the passage of the blood stream, the pulse wave of the artery on the side of heart is detected with the first pressure sensor 1 while the pulse wave of the artery on the peripheral side is detected with the second pressure sensor 2. Thus, a time difference between the pulse waves is obtained as blood viscosity measuring data to be outputted from an output device 4.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood viscosity monitoring device for non-invasively observing the blood viscosity of an examinee's artery by observing the waveform of an arterial pulse wave.

0002

2. Description of the Related Art Conventionally, electrocardiograms, ultrasonic diagnostic devices, and the like have been used to examine heart diseases. In addition, the arterial pulse wave, which is related to the movement of the heart, contains important information that indicates the state of blood circulation function, so it is widely used to judge the quality of blood circulation function. Observations of volume pulse waves showing the This arterial pulse wave can be detected by converting pressure changes caused by heartbeat into electrical signals using piezo elements, condenser microphones, etc.
Methods such as optically detecting changes in blood flow using the modulation effect of hemoglobin in blood have been adopted.

[0003] In Oriental medicine, the medical condition of the patient is determined by exclusively tactile pulse diagnosis based on the pulse of the artery at the radial capsule-shaped protrusion on the inside of the wrist. Pulse diagnosis in Oriental medicine involves dividing the Sunkuchi pulse into three parts: upper, middle, and lower, that is, Sun, Guan, and Shaku, and grasping the pulse Qi of the two meridians that appear in each part. The above dimension refers to the distal side of the wrist artery, and the pulse of this dimension represents the state of health of a person from the head to the chest. In addition, Seki refers to the middle point between the peripheral side of the artery and the heart side, and the pulse of this Seki is
It represents the state of health from the chest to the navel. Furthermore, shaku refers to the heart side of the artery, and represents the state of health from the navel to the toes.

[0004] Conventionally, as a device for obtaining an arterial pulse wave from an artery of the human body using an infrared sensor, a pressure sensor, etc. and performing a pulse diagnosis by observing the waveform, for example, a pulse diagnosis device as disclosed in Japanese Patent Publication No. 57-52054 has been used. The device is known.

As shown in FIG. 9, this pulse diagnostic device includes three pressure sensors 51, 52, and 5, which convert arterial pulse waves at three locations, ie, tsuki, and shiku, into electrical signal waveforms.
3, and a covering band 55 for attaching these pressure sensors 51, 52, 53 to the wrist 54 of the examinee and pressing it against the artery. Each of the pressure sensors 51, 52, 53 is
They are placed side by side on the examinee's wrist 54, that is, on the artery in front, and the covering band 55 is wrapped and worn over the wrist 54 of the examinee. Then, compressed air is sent from an air pump through a conduit 56 to an air bag (not shown) provided in the cover band 55, and by adjusting the amount of air, the pressure applied to the artery is varied and the arterial pulse wave is adjusted. Changes can be measured.

[0006] The pressure sensors 51, 52, and 53 are composed of, for example, an electrostatic microphone or a piezoelectric microphone. Specifically, for example, a high DC voltage is applied between the diaphragm electrode of an electrostatic microphone and a fixed electrode through a resistance of several tens of MΩ, and the diaphragm electrode is brought into direct contact with the pressure-detecting point, the arterial artery. The pressure changes the distance between the diaphragm electrode and the fixed electrode, changing the capacitance, and the voltage generated at this time is detected. Each of the pressure sensors 51, 52, and 53 is connected to an electromagnetic oscillograph (not shown) via connection cords 51a, 52a, and 53a, respectively, and the measured arterial pulse waves are recorded on recording paper or the like for waveform observation. It is now possible to do so.

[0007]

[Problems to be Solved by the Invention] Conventionally, as mentioned above, electrocardiograms and ultrasonic diagnostic devices have been used to examine heart diseases, but arteries that change with internal organs diseases such as heart diseases and liver diseases have been used. There is no way to non-invasively measure blood viscosity within the body, and it has not been possible to use blood viscosity information to determine internal organ disease.

[0008] The present invention was proposed in view of the above circumstances, and aims to make it possible to utilize information on blood viscosity in determining internal organ diseases, and requires skill. The purpose of the present invention is to provide a blood viscosity observation device that can non-invasively and accurately determine the viscosity of blood in an artery of a subject.

[0009]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the blood viscosity observation device according to the present invention detects an arterial pulse wave on the heart side by being pressed against a detection area along an artery by a pressing means. a first pressure sensor that detects a peripheral arterial pulse wave, a second pressure sensor that detects a peripheral arterial pulse wave, and a first level detection that detects that a detection output signal of a predetermined level or higher is obtained by the first pressure sensor. means, a second level detection means for detecting that a detection output signal of a predetermined level or higher is obtained by the second pressure sensor, and a blood flow passage through which a detection output signal from the second level detection means is obtained. When the limit state is reached, the measurement is started by a detection output signal from the pressure control means for controlling the pressing force by the pressing means and the first level detection means, and the measurement is ended by the detection output signal from the second level detection means. and a timer means, and an output means for outputting the measurement data by the timer means as blood viscosity measurement data, the first and second level detection means being in a blood flow passage limit state in which a detection output signal by the second level detection means is obtained. The blood viscosity observation data is obtained from the detection output signal from the pressure sensor.

0010

[Operation] In the blood viscosity observation device according to the present invention, the pressure means presses the first and second pressure sensors to compress the artery, and the second pressure sensor detects the peripheral arterial pulse wave to a predetermined area. The pressing force of the pressing means is controlled by the pressing control means to a blood flow passage limit state where a level detection output signal is obtained. In the blood flow limit state, the first pressure sensor detects an arterial pulse wave on the heart side, the second pressure sensor detects an arterial pulse wave on the peripheral side, and the time difference is calculated as the blood viscosity. Obtained as measurement data.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the blood circulation function observation device according to the present invention will be described in detail below with reference to the drawings.

The blood circulation function observation device according to the present invention is configured as shown in FIG. 1, for example. The blood circulation function observation device shown in Fig.
The present invention is applied to a pulse diagnosis device that detects the pulse wave of the shaku and determines the medical condition of the examinee.It detects the arterial pulse wave of the shuku, seki, and shaku and converts it into an electrical signal waveform. Detection output signals S1, S2, S3 from each of these pressure sensors 1, 2, 3 are provided.
is supplied to an output device 4 for waveform observation.

[0013] The first to third pressure sensors 1, 2, 3
is constituted by a pressure-electric transducer such as a piezoelectric microphone, and detects the arterial pulse waves of the above dimensions as pressure changes. These first to third pressure sensors 1, 2, and 3 are arranged on the inner wall portion of a fixing plate 6 whose both ends are connected by a covering band 5 worn on the wrist of the examinee, as shown in FIG. has been done. The first to third pressure sensors 1, 2, and 3 are operated by injecting air into the air bag 7 provided in the cover band 5, so that the pressure sensors 1, 2, and 3 are connected to is pressed against the detection site corresponding to the patient's wrist, and as shown in FIG. 3, the artery 21 is occluded through the skin tissue 20 of the examinee's wrist.

Air is injected into the air bag 7 provided in the covering band 5 by an air pump (not shown) controlled by a pressure control section 8, and an exhaust valve (not shown) controlled by the pressure control section 8 is injected into the air bag 7. It is designed to be exhausted through the Furthermore, the first to third air bags 7
The pressing force of the pressure sensors 1, 2, and 3 is measured by the fourth pressure sensor 9.
It is designed to be detected by

The first pressure sensor 1, which detects the above-mentioned scale, that is, the arterial pulse wave on the heart side, supplies its detection output signal S1 to the output device 4, and the first
The signal is supplied to a level detection circuit 10 and a notch detection circuit 11.

The first level detection circuit 10 detects that the first pressure sensor 1 has obtained a detection output signal S1 of a predetermined level or higher. The detection output signal from the first level detection circuit 10 is supplied to the first and third timer circuits 12 and 15 as a timer start signal.

Further, the first notch detection circuit 11 includes:
The detection output signal S1 by the first pressure sensor 1, that is, the notch portion (waveform missing portion) included in the arterial pulse wave on the heart side is detected. This first notch detection circuit 11 is
A low-pass filter 11A extracts the fundamental wave component of the detection output signal S1 from the first pressure sensor 1, and the fundamental wave component extracted by the low-pass filter 11A is subtracted from the detection output signal S1 from the first pressure sensor 1. and a subtracter 11B. The first notch detection signal obtained as a subtracted output signal by the subtracter 11B is supplied to the first timer circuit 12 as a timer stop signal, and is also supplied to the integration circuit 14, and is further supplied to the second timer circuit 13. is supplied as a timer start signal.

After the first timer circuit 12 detects in the first level detection circuit 10 that the first pressure sensor 1 has obtained a detection output signal S1 of a predetermined level or higher, The time required for the first notch detection circuit 11 to detect the notch portion included in the detection output signal S1 of the first pressure sensor 1 is measured. The measurement output signal from this first timer circuit 12 is supplied to the output device 4. Further, the integration circuit 14 integrates the first notch detection signal obtained by the first notch detection circuit 11. The integrated output signal from this integrating circuit 14 is supplied to the output device 4.

Further, the second pressure sensor 2 which detects the arterial pulse wave at the junction point, that is, between the heart side and the peripheral side, supplies its detection output signal S2 to the output device 4, and also The signal is supplied to the level detection circuit 16 and notch detection circuit 17.

The second level detection circuit 16 detects that the second pressure sensor 2 has obtained a detection output signal S2 of a predetermined level or higher. The detection output signal from the second level detection circuit 16 is supplied to the output device 4 and the pressure control section 8, and is also supplied to the third timer circuit 15 as a timer stop signal, and is further supplied to the third timer circuit 15 as a timer stop signal. It is supplied to circuit 18 as a first latch signal.

The third timer circuit 15 receives a detection output signal S1 of a predetermined level or higher from the first pressure sensor 1.
The first level detection circuit 10 detects that the second pressure sensor 2 has obtained a detection output signal S2 of a predetermined level or higher. Measure the time until it is detected. The measurement output signal from this third timer circuit 15 is supplied to the output device 4.

[0022] Furthermore, the second notch detection circuit 17 includes:
The detection output signal S2 by the second pressure sensor 2, that is, the notch portion (waveform missing portion) included in the arterial pulse wave intermediate between the heart side and the peripheral side is detected. This second notch detection circuit 17 includes a low-pass filter 17A that extracts the fundamental wave component of the detection output signal S2 from the second pressure sensor 2, and a low-pass filter 17A that extracts the fundamental wave component of the detection output signal S2 from the second pressure sensor 2, and a low-pass filter 17A that extracts the fundamental wave component extracted by the low-pass filter 17A. and a subtracter 17B that subtracts from the detection output signal S2 from the pressure sensor 2. The second notch detection signal obtained as the subtracted output signal by the subtracter 17B is supplied to the second timer circuit 13 as a timer stop signal.

The second timer circuit 13 detects the notch portion included in the detection output signal S1 of the first pressure sensor 1 with the first notch detection circuit 11, and then detects the notch portion included in the detection output signal S1 of the first pressure sensor 1. The time required for the second notch detection circuit 17 to detect the notch portion included in the detection output signal S2 of the pressure sensor 2 is measured. The measurement output signal from this second timer circuit 13 is supplied to the output device 4.

Furthermore, the third pressure sensor 3 which detects the above-mentioned dimension, that is, the arterial pulse wave on the peripheral side, supplies its detection output signal S3 to the above-mentioned output device 4, and also
is supplied to the level detection circuit 19 of.

The third level detection circuit 19 detects that the third pressure sensor 3 has obtained a detection output signal S3 of a predetermined level or higher. The detection output signal from this third level detection circuit 19 is transmitted to the second latch circuit 2.
0 as the second latch signal.

Furthermore, the first air bag 7
The fourth pressure sensor 9, which detects the pressing forces of the third pressure sensors 1, 2, and 3, supplies its detection output signal S4 to the first and second latch circuits 18, 20.

The first latch circuit 18 converts the detection output signal S4 from the fourth pressure sensor 9 into the first latch signal, that is, the second level detection circuit 1.
6 is latched by the detection output signal, and the latch output signal is supplied to the subtracter 21 and the divider 22. This first
The latch output signal from the latch circuit 18 is a detection output signal S2 of a predetermined level or higher by the second pressure sensor 2 when the blood flow completely passes under the first pressure sensor 1.
shows the total blood flow pressure P1 obtained.

Further, the second latch circuit 20 converts the detection output signal S4 from the fourth pressure sensor 9 into the second latch circuit 20.
, that is, the detection output signal from the third level detection circuit 19 , and the latch output signal is supplied to the subtracter 21 . The latch output signal from this second latch circuit 20 is transmitted to the second pressure sensor 2.
The blood flow completely passes through the third pressure sensor 3 below.
shows the blood flow total passing pressure P2 at which a detection output signal S4 of a predetermined level or higher is obtained.

The subtracter 21 extracts the latch output signal from the first latch circuit 18 from the second latch circuit 2.
The latch output signal by 0 is subtracted and the subtracted output signal is supplied to the divider 22. The subtracted output signal by the subtractor 21 is calculated by combining the blood flow total passage pressure P1 at which the blood flow completely passes under the first pressure sensor 1, which is indicated by the latch output signal of the first latch circuit 18, and the 2 shows the pressure difference P1 - P2 between the blood flow total passage pressure P2 at which the blood flow completely passes under the second pressure sensor 2, which is indicated by the latch output signal of the second latch circuit 20.

The divider 22 is the subtracter 2.
By dividing the subtracted output signal by 1 by the latch output signal from the first latch circuit 18, the pressure difference P1 - P2 indicated by the subtracted output signal is normalized. The divided output signal from the divider 22, that is, the normalized pressure difference information (P1-P2)/P1, is supplied to the output device 4.

[0031] The pulse diagnostic device having such a configuration is used by switching its operating state to the first to third operating modes.

First, in the first operation mode, an air pump and an exhaust valve (not shown) are controlled by the pressure control section 8, and the first to third pressure sensors 1, 2, and 3 are controlled by the air bag 7. The pressing force is gradually changed from the blood flow cutoff state to the full passage state, and the first to third pressure sensors 1
, 2, and 3, the waveforms of the detection output signals S1, S2, and S3 are observed by the output device 4. This makes it possible to determine the medical condition of the patient by observing the arterial pulse waves of Sunkuchi, Seki, and Shaku in Oriental medicine.

[0033] Here, the first to third pressure sensors 1
, 2, 3 detection output signals S1, S2, S3 are as follows:
the first to third pressure sensors 1 using the air bag 7;
When the pressing force in steps 2 and 3 is gradually changed from the blood flow blocking state to the full blood flow passing state, as shown in FIG. 4, first the signal level of the detection output signal S1 from the first pressure sensor 1 located on the heart side increases, then the signal level of the detection output signal S2 from the second pressure sensor 2 located in the center rises, and finally the signal level of the detection output signal S3 from the third pressure sensor 3 located on the peripheral side rises. When the pressure increases and the pressing force decreases, the signal levels of the detection output signals S1, S2, and S3 from the first to third pressure sensors 1, 2, and 3 simultaneously decrease.

In the second operation mode, the pressing force of the first to third pressure sensors 1, 2, and 3 by the air bag 7 is gradually reduced from the blood flow cutoff state to the second level. Based on the detection output signal from the second level detection circuit 16, the pressure control unit 8 controls the pressure control unit 8 to maintain the pressure P1 constant in the blood flow passage limit state where the detection output signal from the detection circuit 16 is obtained. Not control the air pump and exhaust valve.

[0035] Here, in the blood flow passage limit state, the first
When the waveforms of the detection output signals S1 and S2 obtained from the second pressure sensors 1 and 2 are observed by the output device 4,
In FIG. 5, the waveform of the detection output signal S1 of the first pressure sensor 1 is shown by a solid line, and the waveform of the detection output signal S2 of the second pressure sensor 2 is shown by a broken line. When the circulatory function is normal, the waveform becomes a mountain-like waveform that continues smoothly from the time point t1 when cardiac contraction starts to the time point t2 when the aortic valve closes.

On the other hand, if there is an abnormality in the blood circulation function of the examinee, a notch will occur midway from the above-mentioned cardiac contraction start time t1 to the aortic valve closure time t2. For example, in the case of a pressure abnormality that propagates quickly due to a valve abnormality, the waveform of the detection output signal S1 of the first pressure sensor 1 is shown as a solid line in FIG. 6, and the waveform of the detection output signal S2 of the second pressure sensor 2 is shown in FIG. As shown by the broken line in the waveform, notches n1,
n2 appears at approximately the same time tn. Furthermore, in the case of a flow abnormality that propagates slowly due to an abnormality in the myocardium, for example, the waveform of the detection output signal S1 of the first pressure sensor 1 is shown as a solid line in FIG. As shown by the broken line in the waveform of S2, notches n1 and n2 with a time difference Δt appear.

[0037] In the second operation mode, this pulse diagnostic device sets the time tn from the cardiac systole start time t1 until the notch n1 appears in the detection output signal S1 of the first pressure sensor 1 to the first The timer circuit 12 measures the time from when the notch n1 appears in the detection output signal S1 of the first pressure sensor 1 until the notch n2 appears in the detection output signal S2 of the second pressure sensor 2, that is, the notch. Time difference Δ between n1 and n2
t is measured by the second timer circuit 13, and the generation time information tn, Δt of each notch n1, n2 is displayed on the output device 4.

In this way, by displaying the measurement data tn and Δt from the first and second timer circuits 12 and 13 as blood circulation function observation data on the output device 4, no skill is required. The state of the blood circulation function of a subject can be determined non-invasively and accurately.

Furthermore, the first pressure sensor 1 detects the notch n1 appearing in the detection output signal S1 of the first pressure sensor 1.
The disease state can be quantified by integrating the first notch detection signal from the notch detection circuit 11 by the integration circuit 14 to find the size (area) of the notch n. By displaying the integrated output signal as blood circulation function observation data on the output device 4, the disease state can be determined more accurately.

Further, in the second operation mode, the third timer circuit 15 detects that the first pressure sensor 1 has obtained a detection output signal S1 of a predetermined level or higher. The time from the detection by the circuit 10 until the second level detection circuit 16 detects that the detection output signal S2 of a predetermined level or higher is obtained by the second pressure sensor 2, that is, the first The time τ required for the blood to move by the distance L between the pressure sensor 1 and the second pressure sensor 2 is measured.

[0041] Here, in the blood flow passage limit state, the first
The speed v at which blood moves as a thin film flow under the pressure sensor 1 of
As shown in equation 1,

[Math 1]

Since it depends on the blood viscosity μ, the blood viscosity μ can be determined by measuring the time τ required for the blood to move by the distance L between the first pressure sensor 1 and the second pressure sensor 2. It can be estimated.

The output device 4 to which the output signal of the third timer circuit 15 is supplied is configured so that the blood moves by a distance L between the first pressure sensor 1 and the second pressure sensor 2. The measured value of the time τ required for this is displayed as observation data of blood viscosity μ. This makes it possible to obtain blood viscosity information that quantifies the blood viscosity μ of the artery of the patient.

Furthermore, in the second operation mode, a reference waveform signal based on the detection output signal S1 from the first pressure sensor 1 and a detection output signal S2 from the second pressure sensor 2 are compared. The waveform is displayed on the output device 4 as blood vessel inner wall condition observation information. The blood moving under the first pressure sensor 1 as a thin film flow in the blood flow limit state exhibits a wavefront (indicating an increase or decrease in pressure) depending on the rough state of the inner wall of the artery. The detection output signal S2 from the pressure sensor 2 of No. 2 is as shown in FIG.
The waveform corresponds to the rough state of the inner wall of the artery. Therefore, information on the roughness of the inner wall of the artery can be obtained from the patient.

In this second operation mode, the waveforms of the detection output signals S1 and S2 by the first pressure sensor 1 on the heart side and the second pressure sensor 2 in the center are observed, but the waveforms of the detection output signals S1 and S2 on the peripheral side are observed. By having the third pressure sensor 3 in the position, it is possible to remove the influence of blood on the peripheral side and perform highly accurate waveform observation.

Next, in the third operation mode, the pressing force is adjusted so that the pressing force of the air bag 7 on the first to third pressure sensors 1, 2, 3 is gradually reduced from the blood flow cutoff state. The control unit 8 controls an air pump and an exhaust valve (not shown), and normalized pressure difference information (P1-P2)/P1 is indicated by the division output signal from the divider 22.
is displayed on the output device 4 as arterial stiffness observation information.

Here, as in this pulse diagnosis device, first to third pressure sensors 1 and 2 are arranged adjacently along an artery.
, 3, the load from the first pressure sensor 1 on the heart side and the third pressure sensor 3 on the peripheral side affects the center where the second pressure sensor 2 is located, and the center load increases. The increase in load has a positive correlation with the hardness of the artery in the wrist of the examinee who presses the first to third pressure sensors 1, 2, and 3. Therefore, the first
Blood flow total passage pressure P1 at which the blood flow completely passes under the pressure sensor 1 of , and Blood flow total passage pressure P2 at which the blood flow completely passes under the central second pressure sensor 2. Difference P
1 - P2 can be used as information indicating the hardness of the wrist artery of the subject. In addition, since the blood flow total passage pressure point is the balance point of the systolic blood pressure and the load via the skin tissue, the pressure difference P1 - P2 is hardly affected by individual differences in blood pressure and skin tissue.

In this embodiment, the pressure difference P1 - P2
is normalized by the divider 22 and displayed on the output device 4 as arterial stiffness observation information that eliminates individual differences due to blood pressure and the like. This makes it possible to obtain arterial stiffness observation information for the patient.

[0049]

As described above, in the blood viscosity observation device according to the present invention, in the blood flow passage limit state where a detection output signal of a predetermined level is obtained by the second pressure sensor that detects the peripheral arterial pulse wave, , the first detecting the arterial pulse wave on the heart side
Since blood viscosity observation data quantified as the time difference between the detection output signal from the pressure sensor and the detection output signal from the second pressure sensor that detects the peripheral arterial pulse wave is output from the output means, skill is required. The blood viscosity of the patient can be accurately determined non-invasively. Therefore, information on blood viscosity can be used to determine visceral diseases.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a pulse diagnostic device to which the present invention is applied.

FIG. 2 is a perspective view showing the arrangement of three pressure sensors used in the pulse diagnostic device shown in FIG. 1;

FIG. 3 is a sectional view showing a state in which an artery is pressed by three pressure sensors in the pulse diagnosis device shown in FIG. 1;

FIG. 4 is a characteristic diagram showing changes in signal levels of detection output signals obtained by three pressure sensors in the pulse diagnosis device shown in FIG. 1;

[Figure 5] When the blood circulation function of the examinee is normal, Figure 1
FIG. 3 is a waveform diagram showing waveforms of detection output signals obtained by the first and second pressure sensors in the pulse diagnostic device shown in FIG.

FIG. 6 is a waveform chart showing observed waveforms of pressure abnormalities in blood circulation function by the pulse diagnostic device shown in FIG. 1;

FIG. 7 is a waveform chart showing observed waveforms of flow abnormalities in blood circulation function by the pulse diagnosis device shown in FIG. 1;

FIG. 8 is a waveform diagram showing observed waveforms of the state of the inner wall of a blood vessel by the pulse diagnosis device shown in FIG. 1;

FIG. 9 is a perspective view showing a pulse wave detection device that detects pulse waves of Sunkuchi, Seki, and Shaku in Oriental medicine.

[Explanation of symbols]

1, 2...Pressure sensor ４・・・・・・Output device 7・・・・・・Air bag 9...Press control section 10, 16...Level detection circuit 15... Timer circuit

Claims (1)

[Claims] 1. A first pressure sensor that is pressed against a detection area along an artery by a pressing means to detect an arterial pulse wave on the heart side, and a second pressure sensor that detects an arterial pulse wave on the peripheral side; a first level detection means for detecting that a detection output signal of a predetermined level or higher is obtained by the first pressure sensor; and a first level detection means for detecting that a detection output signal of a predetermined level or higher is obtained by the second pressure sensor. a second level detection means for detecting the level; a pressure control means for controlling the pressing force by the pressing means; A timer means for starting measurement according to a detection output signal from the detection means and ending the measurement according to a detection output signal from the second level detection means, and an output means for outputting the measurement data by the timer means as blood viscosity measurement data. Blood viscosity observation data is obtained from the detection output signals of the first and second pressure sensors in a blood flow passage limit state where the detection output signal of the second level detection means is obtained. Viscosity observation device.