JP2000271099A - Peripheral vessel resistance measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a peripheral vessel resistance measuring instrument capable of noninvasively and continuously measuring a peripheral vessel resistance. SOLUTION: The pressure maximum time point tamx indicating the maximum pressure Pmax in one pulse wave of the pressure pulse wave detected by a pressure pulse wave sensor 38 is determined by a pressure maximum time point determining means 74. The pulse pressure of the pressure pulse wave from the maximum time point tamx to the time after 180 msec is normalized and the normalizing pulse wave W is determined by a pulse wave normalizing means 76. The peripheral vessel resistance TPR of a living body is calculated from the relation of the equation: TPR=a+bx in accordance with this normalizing pulse wave W by a peripheral vessel resistance calculating means 78 and, therefore, the noninvasive and continuous measurement of the peripheral vessel resistance TPR is made possible. In the equation, a and b are empirically determined constants and x is a variable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for measuring peripheral vascular resistance of a living body in a non-invasive manner.

[0002]

2. Description of the Related Art It is very useful to study peripheral vascular resistance in studies on the regulation mechanism of blood pressure or studies on circulatory dynamics. A conventional peripheral vascular resistance measuring device is Swan-Ga
A device using an nz catheter was mainly used, and a cardiac output was calculated using the catheter, and a peripheral vascular resistance was calculated.

[0003]

However, the above-mentioned conventional peripheral vascular resistance measuring apparatus is invasive and invasive. That is, since it is necessary to insert a catheter into the heart, an X-ray fluoroscope provided in a special examination room is required. In addition, there is a great burden on the patient, and there is a risk of infection due to vascular puncture. Further, the conventional peripheral blood vessel resistance measuring device has a problem that data can be obtained only every several tens of seconds at the shortest. This limits its application to a wide range of clinical trials.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a peripheral vascular resistance measuring device capable of non-invasively and continuously measuring peripheral vascular resistance. Is to do.

[0005]

The gist of the present invention for achieving the above object is to provide a peripheral vascular resistance measuring device for non-invasively measuring the peripheral vascular resistance of a living body,
A pressure pulse wave detecting device for continuously and non-invasively detecting the pressure pulse wave of the artery of the living body, and a highest pressure point indicating the highest pressure in one pulse wave of the pressure pulse waveform detected by the pressure pulse wave detecting device. Pressure pulse time determining means for determining a normalized pulse wave by normalizing the pulse pressure of the pressure pulse waveform for a predetermined time from the pressure maximum time point determined by the pressure maximum time point determining means. And a peripheral blood resistance calculating means for calculating the peripheral blood vessel resistance of the living body based on the normalized pulse wave normalized by the pulse wave normalizing means from a preset relationship. is there.

[0006]

In this manner, the highest pressure point indicating the highest pressure in one pulse wave of the pressure pulse waveform detected by the pressure pulse wave detecting device is determined by the peak pressure time determining means. The normalizing means normalizes the pulse pressure, that is, the amplitude of the pressure pulse waveform for a predetermined time from the highest pressure point to determine a normalized pulse wave, and the peripheral blood vessel resistance calculating means preliminarily determines the pulse wave based on the normalized pulse wave. Since the peripheral vascular resistance of the living body is calculated from the set relationship, the peripheral vascular resistance can be measured noninvasively and continuously.

[0007]

In another embodiment of the present invention, preferably, the predetermined relationship used in the peripheral vascular resistance calculating means is:
A neural network previously learned based on a plurality of input waveforms schematically representing a plurality of the normalized pulse waves representing different peripheral vascular resistances and a reference output value sequence set corresponding to the input waveforms Is included. This has the advantage that the relationship between the normalized pulse wave normalized by the pulse wave normalizing means and the peripheral vascular resistance of the living body is easily set.

[0008] Preferably, the peripheral vascular resistance measuring device includes an electrocardiographic lead device for detecting an electrocardiographic lead waveform of the living body through an electrode contacted with the living body, and a periodicity of the electrocardiographic lead waveform. A single pulse wave determining means for determining a single pulse wave of the pressure pulse waveform based on a predetermined portion to be repeated. With this configuration, the single pulse wave determining means determines one pulse wave of the pressure pulse waveform based on a predetermined portion of the electrocardiographic lead waveform. There is an advantage that the pressure maximum point can be determined. Incidentally, when determining a single pulse wave based on a predetermined portion of the pressure pulse wave that repeats periodically, for example, when determining a single pulse wave based on a rising point of the pressure pulse wave, the rise of the pressure pulse wave is determined. In some cases, the pulse wave cannot be determined accurately because the point is unclear.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a block diagram illustrating the configuration of a peripheral vascular resistance measuring device 10 to which the present invention has been applied.

Referring to FIG. 1, a peripheral vascular resistance measuring device 10
Is mounted to the living body wrist 12 of pressing the radial artery 16 from above the body surface 14, pressure pulse wave detection to output the pulse-wave signal SM ₁ to detect the pressure pulse wave from the radial artery 16 A probe 18 and an electrocardiographic wave indicating the action potential of the myocardium are detected,
The ECG device 20 for outputting the ECG signals SM ₂ indicative of the ECG wave, processes the pressure-pulse-wave signal SM ₁ and the ECG signal SM _2, operation control for calculating the peripheral vascular resistance TPR The apparatus includes a device 22 and a display 24 for displaying the peripheral vascular resistance TPR and the like calculated by the arithmetic and control unit 22.

As shown in detail in FIG. 2, the pressure pulse wave detecting probe 18 has a case 28 for accommodating a sensor housing 26 in the form of a container, and moves the sensor housing 26 in the width direction of the radial artery 16. And a screw shaft 32 screwed to the sensor housing 26 and rotationally driven by a motor (not shown) provided in a driving unit 30 of the case 28. A mounting band 34 is attached to the case 28 so that the opening end of the container-shaped sensor housing 26 is detachably attached to the wrist 12 by the mounting band 34 with the open end facing the body surface 14 of the human body. Has become. The sensor housing 26
Inside the pressure pulse wave sensor 3 via a diaphragm 36.
8 are provided so as to be relatively movable and protrude from the open end of the sensor housing 26, and the pressure chamber 40 is
Are formed. The pressure chamber 40 is supplied with pressurized air from an air pump 42 via a pressure regulating valve 44, whereby the pressure pulse wave sensor 38 is connected to the pressure chamber 4.
It is pressed against the body surface 14 with a pressing force corresponding to the pressure within 0. In this embodiment, the pressing force of the pressure pulse wave sensor 38 is indicated by the pressure in the pressure chamber 40 (unit: mmHg).

The sensor housing 26 and the diaphragm 36 constitute a pressing device 46 for pressing the pressure pulse wave sensor 38 toward the radial artery 16.
2 and a motor (not shown) are used to change the pressing position at which the pressure pulse wave sensor 38 is pressed in the width direction of the radial artery 16 to change the pressing position, ie, the width direction moving device 4.
8.

The pressure pulse wave sensor 38 has a pressing surface 50 made of, for example, a semiconductor chip made of single crystal silicon or the like.
A large number of semiconductor pressure-sensitive elements (not shown) are arranged at regular intervals of about 0.2 mm in the width direction of the radial artery 16, that is, in the direction of movement of the pressure pulse wave sensor 38 parallel to the screw axis 32. When the wrist 12 is pressed onto the radial artery 16 on the body surface 14 of the wrist 12, a pressure vibration wave or pressure pulse wave generated from the radial artery 16 and transmitted to the body surface 14 is detected. The pressure pulse wave signal SM ₂ representing the pulse wave is supplied to the arithmetic and control unit 22 via the A / D converter 52. Therefore, in this embodiment, the pressure pulse wave sensor 38 functions as a pressure pulse wave detection device.

The electrocardiograph 20 continuously detects an electrocardiogram, which is a so-called electrocardiogram, showing an action potential of the myocardium through a plurality of electrodes 54 attached to a predetermined portion of a living body. A signal SM ₂ indicating the electrocardiogram is supplied to the arithmetic and control unit 22. FIG. 3 shows a pressure pulse wave represented by the pressure pulse wave signal SM ₁ detected by the pressure pulse wave sensor 38,
Shows an example of ECG waves representing the ECG signal SM ₂ detected by and electrocardiograph device 20.

The arithmetic and control unit 22 includes a CPU 56 and an R
A so-called microcomputer having an OM 58, a RAM 60, an I / O port (not shown), and the like is configured. The CPU 56 executes signal processing using a storage function of the RAM 60 according to a program stored in the ROM 58 in advance. A drive signal is output to the drive unit 30 to adjust the pressing position of the pressure pulse wave sensor 38, and the air pump 4
A drive signal is output to the pressure regulator 2 and the pressure regulating valve 44 via a drive circuit (not shown) to regulate the pressure in the pressure chamber 40.

That is, the arithmetic and control unit 22 causes the pressing device 46 to press the pressure pulse wave sensor 38 at a relatively small first pressing value P ₁ which is sufficiently lower than the optimum pressing force, and in that state, The pressing position is adjusted so that one of the pressure detecting elements of the pressure pulse wave sensor 38 which shows the maximum pulse wave amplitude is located at a predetermined central portion in the arrangement direction of the pressure detecting elements. Subsequently, the pressing force of the pressure pulse wave sensor 38 is continuously changed, and the optimum pressing force for making a part of the blood vessel wall of the radial artery 16 substantially flat based on the pressure pulse wave obtained in the changing process. P _HDPO is determined and its optimal pressing force P
_The pressure regulating valve 44 is controlled so as to maintain _HDPO .

Then, the arithmetic and control unit 22 converts the pressure pulse wave signal SM ₁ supplied from the pressure pulse wave sensor 38 together with the electrocardiographic lead signal SM ₂ supplied from the electrocardiographic lead device 20 into a magneto-optical disk or the like. It is stored in the external storage device 62, and calculates the peripheral vascular resistance TPR based on the external storage device 62 the pressure-pulse-wave signal SM ₁ is stored in and ECG signal SM _2.

FIG. 4 is a functional block diagram for explaining a main part of the peripheral blood vessel resistance TPR determining function of the arithmetic and control unit 22 in the peripheral blood vessel resistance measuring apparatus 10. The waveform storage means 70 _{converts the} pressure pulse wave signal SM ₁ supplied from the pressure pulse wave sensor 38 into an electrocardiographic lead during the process of the pressure pulse wave sensor 38 pressing the radial artery 16 with the optimum pressing force P _HDPO. together with the signal SM _2, it is stored in the external storage device 62.

The single-pulse-wave determining means 72 is provided between predetermined portions of the electrocardiographic lead waveform represented by the electrocardiographic lead signal SM ₂ stored in the external storage device 62 by the waveform storage means 70, for example, between R-waves. Between the R waves, the electrocardiogram lead signal SM ₂
And the pressure pulse wave signal SM stored in the external storage device 62
_One pulse wave is determined. Thus Ichimyaku wave of pressure pulse wave signal SM ₁ which is determined includes each one by one point minimum pressure P _min and the maximum pressure P _max for each one heartbeat, as shown in FIG.

The highest pressure point determining means 74 determines the highest pressure point indicating the highest pressure P _max for each pulse wave of the pressure pulse wave represented by the pressure pulse wave signal SM ₁ determined by the _single pulse wave determining means 72. Determine t _max .

The pulse wave normalizing means 76 uses the _maximum pressure time t _max determined by the maximum pressure time determining means 74 as a reference point to normalize a pulse pressure, that is, a different amplitude for each pulse wave, and then sets a predetermined time. The pulse pressure of the pressure pulse wave (for example, 180 msec) is normalized to determine a normalized pulse wave W.
That is, the pulse pressure (amplitude) P _max at the _maximum pressure time t _max is set to “1”, the pulse pressure P after the predetermined time is set to “0”, and the pulse pressure of the pressure pulse wave during the predetermined time is normalized, The normalized pulse wave W is assumed. Incidentally, the pressure pulse wave for a predetermined time from the pressure _maximum time point _tmax is the most by comparing the pressure pulse waveforms of various patients whose peripheral vascular resistance is considered to be different, such as a normotensive young woman and a hypertensive elderly man. Peripheral vascular resistance TPR
This is the part where the influence of appears. That is, as shown in FIG. 5 (a diagram schematically showing two pressure pulse waves having different peripheral vascular resistance TPR), when the value of the peripheral vascular resistance TPR is compared with the case where the value is low, the peripheral vascular resistance TPR Is high, the decrease of the pressure pulse wave from the pressure _maximum point _tmax is relatively slow.

The peripheral blood vessel resistance calculating means 78 calculates the peripheral blood vessel resistance TPR of the living body based on the normalized pulse wave W normalized by the pulse wave normalizing means 76 from a preset relationship. For example, the relationship shown in Expression 1 is used as the preset relationship. In Equation 1, a and b are constants experimentally obtained in advance. For example, a = 1690 and b = 2400 are used, and x is a variable.

[0023]

## EQU1 ## TPR = a + bx

The variable x of the equation (1) includes a plurality of input waveform I _n that a plurality of normalized pulse wave W represented schematically represent different peripheral resistance TPR each set corresponding to the input waveform I _n It has been based on the reference output value sequence S _n are those calculated by using the previously trained neural network NN. As shown in FIG. 5, the peripheral vascular resistance TPR is reflected in the normalized pulse wave W, so that the normalized pulse wave W indicates that the peripheral vascular resistance TPR is high. An input waveform I _n schematically representing n types of waveforms up to a normalized pulse wave W indicating
reference output value is set corresponding to _n on the basis of the column S _n, it is to determine the relationship between the normalized pulse wave W and peripheral vascular resistance TPR. The reference output value sequence S _n is a sequence of a set of output layer units as many numbers of the neural network NN, each reference output value sequence S _n, the position of which indicates the maximum value is different in a number of rows It is set as follows.

FIG. 6 shows the neural network NN
And 17 units α _i (i = 1 to 1)
17) and 14 units β _j (j = 1
To 14) and an output layer γ having 16 units γ _k (k = 1 to 16). And this neural network NN is
By using the input waveform I _n and a reference output value sequence S _n of the output layer unit gamma _k as many 16 different, are learned by well-known back-propagation algorithm.

The above input waveform I_nHas a preset 2
The following curve is used. That is, the midpoint of the predetermined time
(That is, when the section to be normalized is 180 msec
Is the pressure maximum time t_max90 msec after)_m
To the normalized pulse wave W obtained from each subject in the resting state.
Equation 2 set based on the upper and lower limits in
At that point, at which point the pulse pressure P becomes "1"
Point t_maxThe point after the predetermined time when the pulse pressure P becomes “0” is
The quadratic curve passing through the added three points is the input waveform I_nDecided to
You. The input waveform I thus determined_nIs that n is large
Normalization when peripheral vascular resistance TPR is large
The pulse wave W is schematically shown. This input waveform I _nThat of
In each case, the point of the maximum pressure when the pulse pressure P is "1"
t_maxAnd the predetermined time after the pulse pressure P is "0"
Except for the point, 17 pulse pressures P obtained every 10 msec
Input layer unit α_iTo enter. Reference output value sequence S_nTo
Is the output layer unit γ_kIs the same number of 16 sequences as
A sequence in which one is "1" and the other is "0",
That is, S₁= [1,0,0 ..., 0], S_Two= [0,
1,0, ... 0], ..., S₁₆= [0,0,0, ... 1]
Can be. Then, the input waveform I_nAnd the corresponding group
Semi-output value sequence S_nAnd a predetermined number of times, for example, 100
A neural network NN that has been trained 10,000 times
Used for the peripheral vascular resistance calculation means 76.

[0027]

## EQU2 ## P ₂ = (n / 20) + ／

The neural network NN
Output signal O output from each output layer unit γ _k
By substituting _k into the polynomial shown in Equation 3, the variable x in Equation 1 is determined. The coefficient of this equation 3 is
Since the coefficient in accordance with the magnitude of peripheral resistance TPR represented by the input waveform I _n has been determined, the input signal normalization pulse wave W is, the more is one where a high peripheral resistance TPR, variable x has a large value. By substituting the variable x determined in this way into Equation 1, the peripheral vascular resistance TPR is calculated.

[0029]

X = (0/15) O ₁ + (1/15) O ₂ ... +
(15/15) O ₁₆

The peripheral blood vessel resistance display means 80 displays the peripheral blood vessel resistance TPR calculated by the peripheral blood vessel resistance calculating means 78 on the display 24.

FIGS. 7 and 8 show the peripheral vascular resistance TP in the arithmetic and control unit 22 of the peripheral vascular resistance measuring device 10.
It is a flowchart explaining the principal part of R determination operation | movement,
7 is a pulse storage routine for storing the pressure pulse wave signal SM ₁ and the ECG signal SM _2, 8, peripheral vascular resistance to calculate the peripheral vascular resistance TPR based on the stored pulse wave This is a calculation routine.

In FIG. 7, first, in step SA1 (hereinafter, the steps are omitted), it is determined whether or not the optimum pressing force P _HDPO has been determined. If the determination of SA1 is denied, the determination of SA1 is repeated. If the determination is affirmed, SA2 corresponding to the following waveform storage means 70 is stored.
In a state where the pressing force of the pressure pulse wave sensor 38 is maintained in the optimum pressing force P _HDPO determined in SA1, the pressure pulse wave signal SM ₁ supplied from the pulse-wave sensor 38, ECG device 20 is stored in the external storage device 62 together with the ECG signal SM ₂ supplied from.

At SA3, it is determined whether or not the signal storage is to be terminated. That is, by determining whether or not a preset storage period has elapsed since the storage was started in SA2 or whether a stop button (not shown) was pressed, the storage in SA2 was terminated. It is determined whether or not. While the determination in SA3 is denied, the storage of the signal in SA2 is continued,
If the determination in SA3 is affirmative, this routine is ended.

The pressure pulse wave signal SM ₁ and the electrocardiographic lead signal SM
_When the storage of ₂ is completed, a peripheral blood vessel resistance calculation routine shown in FIG. 8 is executed. In FIG. 8, first, in SB1 corresponding to the single pulse wave determining means 72, the external storage device 6
2 to determine _one pulse wave of the pressure pulse wave represented by the pressure pulse wave signal SM1 stored in the second pulse wave. Ie, R-wave of the ECG waveform represented by the ECG signal SM ₂ which is stored together with the pressure-pulse-wave signal SM ₁ -
The pressure pulse wave detected between the R waves is determined as a single pulse wave.

Next, S corresponding to the maximum pressure time determination means 74
Steps B2 and SB3 are executed. First, in SB2,
A differential waveform of each pulse waveform determined in SB1 is obtained. Then, in the subsequent SB3, in the differentiated waveform obtained in the SB2, a point at which the value first becomes “0” after a positive number peak is a pressure _maximum time t _ma indicating the maximum pressure P _max.
Determine _x . The positive peak of the differential waveform, so the lowest pressure P _min is a inflection point existing between the highest pressure P _max, then first determines the become points "0" to the highest pressure P _{ma x} Thus, the maximum pressure _Pmax can be reliably determined.

[0036] In subsequent SB4, the pressure pulse wave between 180msec is extracted from圧最high time t _max determined above SB3, the SB5 corresponding to the subsequent pulse normalization means 76,
The pulse pressure of the pressure pulse wave extracted in SB4 is normalized, and a normalized pulse wave W is determined for each pulse wave.

Subsequently, SB6 to SB8 corresponding to the peripheral blood vessel resistance calculating means 78 are executed. First, in SB6, the neural network NN shown in FIG. 6, which is learned in advance based on the the artificially set input waveform I _n and a reference output value sequence S _n as described above, were determined in SB5 normal by an input signal from Kamyakuha W is input, the output signal O _k from the neural network NN is determined.

In the following SB7, the variable x is determined by substituting the output signal O _k determined in the above SB6 into the above equation 3, and the variable x is substituted into the equation 1 in the following SB8. , The peripheral vascular resistance TPR is calculated based on the pressure pulse wave for each beat.

Subsequently, in SB9, a moving average TPR _{AV of} the peripheral vascular resistance TPR calculated in SB8 for a predetermined number of beats (for example, about 10 beats) is calculated. Then, in SB10 corresponds to the subsequent peripheral vascular resistance display unit 80, the moving average TPR _AV peripheral vascular resistance was calculated in SB9 is displayed trend graph on the display unit 24. FIG. 9 is a diagram showing an example of a trend graph displayed in SB10.

As described above, according to the present embodiment, the highest pressure _Pmax in one pulse wave of the pressure pulse waveform detected by the pressure pulse wave sensor 38 is determined by the maximum pressure time point determining means 74 (SB2 to SB3).圧最high time t _amx showing a is determined by the pulse normalization means 76 (SB5), the圧最high time t _amx
The pulse pressure of the pressure pulse wave from after to 180 msec is normalized to determine the normalized pulse wave W, and the peripheral vascular resistance calculating means 78
(SB6 to SB8), the peripheral vascular resistance TPR of the living body is calculated from the relationship of Equation 1 based on the normalized pulse wave W, so that the peripheral vascular resistance TPR is noninvasive and continuous.
Can be measured.

FIG. 10 shows the peripheral vascular resistance TP measured by the peripheral vascular resistance measuring apparatus 10 of this embodiment using a pressure pulse wave.
FIG. 7 is a diagram comparing R with peripheral vascular resistance TPR measured invasively using a Swan-Ganz catheter. FIG.
As shown in FIG. 0, the peripheral vascular resistance TPR measured using the peripheral vascular resistance measuring device 10 shows a good linear positive correlation with the peripheral vascular resistance TPR measured invasively. (R =
0.81, p <0.001)

According to the present embodiment, the preset relations used in the peripheral vascular resistance calculation means 78 (SB6 to SB8) are different from each other.
A plurality of input waveform I _n that a plurality of normalized pulse wave W schematically illustrating representing the R, previously trained neural based on the reference output value sequence S _n which is set in response to the input waveform I _n Since the network includes the network NN, the normalized pulse wave W normalized by the pulse wave normalizing means 76 (SB5)
There is an advantage that the relationship between the blood pressure and the peripheral vascular resistance TPR of the living body can be easily set.

Further, according to the present embodiment, the single pulse wave determining means 72 (SB1) determines the interval between the R and R waves of the electrocardiographic lead waveform as one pulse wave of the pressure pulse waveform. The time point determining means 74 (SB2 to SB3) has an advantage that the pressure _maximum time point t _{max for} each pulse wave can be reliably determined.

While the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-described embodiment, in the peripheral vascular resistance calculation routine of FIG. 8, the peripheral vascular resistance TPR was calculated for every pulse wave for every pulse wave. Peripheral vascular resistance TPR may be calculated for pulse waves every hour.

In the above embodiment, the pressure pulse wave signal SM
₁And electrocardiographic lead signal SM_TwoIs the external storage device 6
2 and the accumulated signal SM₁, SM_TwoBased on
Therefore, the peripheral vascular resistance TPR was calculated. Sand
In addition, the peripheral vascular resistance TPR is calculated offline.
However, the data need not always be stored in the external storage device 62.
And the pressure pulse wave signal SM supplied to the arithmetic and control unit 22.₁You
And electrocardiogram lead signal SM _TwoOnline using
The peripheral blood vessel resistance TPR may be calculated.

In the above-described embodiment, the configuration of the neural network NN used to determine the output signal O _k to be substituted into Equation 3 is composed of an input layer α having 17 units and a hidden layer β having 14 units. , And 16 output units, but the number of units in each layer is not limited to the above. For example, the number of the intermediate layers β may be 14.

In the above-described embodiment, the pressure pulse wave of the radial artery is used. However, a pressure pulse wave detected from another artery such as the dorsal artery or the carotid artery may be used. .

The present invention can be modified in various other ways without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of a peripheral vascular resistance measuring device according to an embodiment of the present invention.

FIG. 2 is an enlarged view illustrating a pressure pulse wave detection probe of the embodiment of FIG. 1 with a part cut away.

FIG. 3 is a diagram exemplifying a pressure pulse wave detected by the pressure pulse wave sensor of the embodiment of FIG. 1 and an electrocardiographic wave detected by an electrocardiograph;

FIG. 4 is a functional block diagram illustrating a main part of a peripheral blood vessel resistance determining function of the arithmetic and control unit in the embodiment of FIG. 1;

FIG. 5 is a diagram schematically showing two pressure pulse waves having different peripheral vascular resistances.

FIG. 6 is a diagram showing an example of a configuration of a neural network used in peripheral vascular resistance calculation means. It is a figure explaining an example of composition.

FIG. 7 is a flowchart illustrating a main part of a peripheral blood vessel resistance determining operation in the control device of the embodiment of FIG. 1, which is a pulse wave storage routine.

8 is a flowchart illustrating a main part of a peripheral blood vessel resistance determining operation in the control device of the embodiment of FIG. 1, which is a peripheral blood vessel resistance calculation routine.

FIG. 9 is a diagram showing an example in which the peripheral vascular resistance obtained in the embodiment of FIG. 1 is trend-displayed on a display.

10 is a diagram comparing the peripheral vascular resistance measured using the pressure pulse wave by the peripheral vascular resistance measuring device of the embodiment of FIG. 1 with the peripheral vascular resistance measured invasively.

[Explanation of symbols]

 10: peripheral vascular resistance measuring device 20: electrocardiographic guiding device 38: pressure pulse wave sensor (pressure pulse wave detecting device) 72: single pulse wave determining means 74: highest pressure point determining means 76: pulse wave normalizing means 78: peripheral Vascular resistance calculation means

Claims (2)

[Claims] 1. A peripheral vascular resistance measuring device for non-invasively measuring peripheral vascular resistance of a living body, comprising: a pressure pulse wave detecting device for continuously detecting non-invasively a pressure pulse wave of an artery of the living body; A pressure maximum time point determining means for determining a pressure maximum time point indicating a maximum pressure in one pulse wave of the pressure pulse waveform detected by the pressure pulse wave detecting device; and a pressure maximum time point determined by the pressure maximum time point determining means. Pulse wave normalizing means for determining a normalized pulse wave by normalizing the pulse pressure of the pressure pulse waveform for a predetermined time; and normalization normalized by the pulse wave normalizing means from a preset relationship. A peripheral vascular resistance calculating means for calculating the peripheral vascular resistance of the living body based on the pulse wave. 2. The preset relationship used in the peripheral vascular resistance calculating means includes a plurality of input waveforms schematically representing a plurality of the normalized pulse waves representing different peripheral vascular resistances, and the input waveform. 2. The peripheral vascular resistance measurement device according to claim 1, further comprising a neural network learned in advance based on a reference output value sequence set in accordance with (1).