JP2998579B2 - Pulse wave measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulse wave measuring device used for health management and diagnosis in a health care room, a medical institution or a general home.

[0002]

2. Description of the Related Art Conventionally, as a pulse wave measuring apparatus of this kind,
The output of the pulse wave sensor that detects an increase or decrease in blood volume at the end of the body such as a fingertip or an earlobe is differentiated twice, and from the magnitude relation of the height (distance from the reference line) of each peak of the resulting waveform. A configuration for determining the characteristics of a waveform is known (for example, Japanese Patent Application Laid-Open No. 57-93036).

FIG. 8 shows a specific example of an index calculation method of this pulse wave measuring device. 8, reference numeral 11 denotes a curve showing an example of a waveform obtained by differentiating the output of the pulse wave sensor twice.
Indicates a position where the height of the waveform 11 becomes 0, that is, a reference line. 8, the height of the first peak 11a in the waveform 11 is a, the height of the second, third, and fourth peaks 11b, 11c, and 11d is b, respectively.
It is described that c and d are used, and the characteristic of the waveform is determined from the magnitude relation between the values of a to d.

[0004]

However, in the configuration of the conventional pulse wave measuring device, when judging the characteristics of the waveform,
Focusing only on the height of each peak of the second derivative waveform, it is an important factor that characterizes the shape of the waveform, and in particular, each peak that is considered to have a deep relationship with the blood pushing force of the heart and the elasticity of blood vessels. The temporal positional relationship was not considered at all, and it was difficult to say that the characteristics of the waveform were sufficiently expressed.

The present invention solves the above-mentioned problem, and provides a pulse wave measuring apparatus which can evaluate a state of blood circulation based on a value reflecting a temporal positional relationship between waveform parts. It is intended to do so.

[0006]

To achieve this object, a first means of the present invention is to provide a pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, and to differentiate the output of the pulse wave sensor. A differential processing section for processing, a rising point detecting section for detecting a temporal position of a rising point of a waveform obtained by differentiation, and a temporal position of a point at which the rising waveform decreases after passing the maximum point and its slope becomes 0 And a pulse rate detector for counting the pulse rate of the test subject, a differential first wave required time detector for detecting a time required from the rising point to reach the tilt 0 point. And a pulse rate correction calculation unit that corrects the required time of the first differential wave to a value corresponding to the measurement at a predetermined reference pulse rate based on the pulse rate obtained thereby.

The second means of the present invention comprises a pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, etc., a differentiation processing section for differentiating the output of the pulse wave sensor, and a waveform obtained by the differentiation. A maximum point detection unit that detects the temporal position of a point that has reached the maximum after rising, and a zero point detection unit that detects the temporal position of a point that decreases after passing through the maximum point and has a slope of 0 And a differential wave descent required time detecting unit for detecting a required descent time of the waveform from the maximum point to the zero point, and a pulse rate detecting unit for counting the pulse rate of the subject. A pulse rate correction calculation unit that corrects the differential wave descent required time to a value corresponding to the measurement at a predetermined reference pulse rate based on the number.

A third means of the present invention comprises a pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a twice-differential processing unit for twice-differentiating the output of the pulse wave sensor, An intersection detection unit that detects a temporal position of a point where a waveform obtained by the differential crosses the reference line, and a second detection unit that detects a required time from the first intersection to the third intersection of the waveform obtained by the intersection detection unit 1 to 3 intersection required time detection unit, having a pulse rate detection unit that counts the pulse rate of the subject, based on the pulse rate obtained thereby, for the first to third intersection required time,
And a pulse rate correction calculating unit for correcting and calculating this to a value corresponding to the measurement at a predetermined reference pulse rate.

Further, a fourth means of the present invention comprises a pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a twice differentiation processing section for performing twice differentiation processing on the output of the pulse wave sensor,
An intersection detector for detecting a temporal position of a point where a waveform obtained by the differential crosses the reference line, and a required time from a second intersection to a third intersection of the waveform obtained by the intersection detector is detected. It has a second to third intersection required time detection unit and a pulse rate detection unit that counts the pulse rate of the subject. Based on the pulse rate obtained by this, or a predetermined value for the value of the second to third intersection required time A pulse rate correction calculation unit that performs a correction calculation to a value corresponding to the measurement at the reference pulse rate.

[0010]

[0011]

[0012]

[0013]

According to the present invention, the first required time for the differential of the pulse wave, the required time for the differential wave to fall, or the required time for the first to third intersections of the second differentiated pulse wave, or the second to third intersections The required time can be corrected to a value equivalent to the reference pulse rate, and even under measurement under different conditions, the subject's blood circulation state, vascular elasticity, and the like can be uniformly compared and evaluated.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pulse wave measuring apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a pulse wave measuring apparatus according to one embodiment of the present invention, and FIGS.
The two types of typical differential pulse waveforms are shown. In each of the figures, a differential pulse wave is shown in the upper part of the figure, and a corresponding twice differential pulse wave is shown in the lower part. FIG. 4 is an operation explanatory diagram in the case where a pulse rate correction calculation is added to the differential pulse wave.

In FIGS. 1 to 4, reference numeral 1 denotes a pulse wave sensor for detecting an increase or decrease in blood volume at the fingertip, 2 a differential processing unit for differentiating the output signal of the pulse wave sensor 1, and 3 a signal output from the differential processing unit. A rising point detector 4 detects the time position of the rising point S ₁ of the waveform A, and the waveform A has the maximum point S ₂
Reduce after passage, gradient 0 point detecting section for detecting a temporal position of the point S ₃ that the slope is 0, 5 rising point S ₁
The differential first-wave required time detector detects a required time T _S13 from the time T reaches the inclination 0 point S ₃ .

Reference numeral 6 denotes a pulse rate detector for counting the pulse rate n (FIG. 4) of the subject. Reference numeral 7 denotes a differential first wave required for the subject having the pulse rate n obtained by the differential first wave required time detector 5. time T _n a predetermined reference pulse rate pulse rate correction calculation unit for correction operation to a value T ₆₀ corresponding to the measurement in (FIG. 4 at 60 beats / min), 8 denotes a control unit for controlling the operations of these units,
Reference numeral 9 denotes a display unit for displaying a measurement result.

Next, the operation of the pulse wave measuring device will be described. The pulse wave signal obtained by the pulse wave sensor 1 is differentiated by the differentiation processing unit 2, and a so-called differentiated pulse wave waveform A
Is detected as Then, the time positions of the rising point S ₁ and the slope 0 point S ₃ of the waveform A are determined by the rising point detecting unit 3.
And the zero-point-of-inclination detection unit 4 detects the required first-wave differential time T _S13, which is the time interval between these.

At this time, on the basis of the pulse rate n simultaneously obtained by the pulse rate detecting section 6, the pulse rate correcting operation section 7 calculates T ₆₀ = T _n (n / 60) shown in FIG. The measurement result is corrected and displayed on the display unit 9 via the control unit 8.

[0021]

FIG. 5 is a block diagram showing another embodiment of the present invention, reference numeral 10 is the maximum point detecting unit for detecting a temporal position of the maximum point S ₂ of the waveform A, 11 from the maximum point S ₁ Slope 0
A differential wave drop required time detecting section for detecting a fall time required T _S23 of the waveform to the point S _3.

The operation in this case is the same as that of FIG. 1, _except that the required differential wave descent time T _S23 is obtained instead of the required differential first wave time T _S13 in FIG.

FIGS. 6 and 7 are block diagrams showing still another embodiment of the present invention corresponding to the third and fourth aspects of the present invention. The differential first wave required time T _S13 obtained by the configuration of FIGS. 6 shows a configuration for more simply and reliably _{obtaining the} differential wave descent required time T _S23 . In FIG. 6, reference numeral 12 denotes a two-time differential processing unit for performing differential processing on the output signal of the pulse wave sensor 1 twice, and reference numeral 13 denotes two times. The point (X ₁ , X ₂ , X ₂₎ where the waveform A ′ of the so-called twice-differentiated pulse wave obtained by differentiation intersects with the reference line X
₃ ) and a third intersection X ₃ (differential pulse) from the first intersection X ₁ (corresponding to S ₁ in the differentiated pulse wave A) obtained by the intersection detector 13. It is a first to third intersection required time detecting unit that detects a required time T _X13 (corresponding to T _S13 in the differential pulse wave A) up to S ₃ in the wave A). 7 indicates a second intersection X ₂ (differential pulse wave A) obtained by the intersection detection unit 13.
The _second to third intersection required time detectors for detecting a required time T _X23 (corresponding to T _S23 in the differential pulse wave A) from the second intersection X ₃ to the _third intersection X ₃ .

According to this configuration, the rising point S ₁ , the maximum point S ₂ , and the zero point S ₃ of the waveform A to be detected in the configurations shown in FIGS. 1 and 5 are all uniformly differentiated twice. Intersections X ₁ , X ₂ , and X ₃ of A ′ with reference line X can be easily and reliably detected by the same detection method (intersection detection unit 13).

Here, some supplementary explanations about the medical significance of the present invention will be added. Generally, a pulse wave is widely used as a means for detecting blood circulation in the human body, and a differentiated pulse wave obtained by differentiating the pulse wave has a plurality of peaks as shown in the upper part of FIG. 2 or FIG. It is known that the waveform becomes a waveform corresponding to the blood flow velocity at the measurement site. Then, the first peak of the waveform, that is, the first differential wave (S _{1 to} S ₃ )
Represents the process of expanding the blood vessel at the measurement site by the blood pushing force of the heart, increasing the blood flow velocity, and then decelerating due to the elasticity of the blood vessel, and some mountains that appear after that It is considered to be an attenuation waveform due to the influence of vascular elasticity.

Therefore, the time required for the first differential wave (T
_S13 ) is a value serving as an index that comprehensively expresses the blood pushing force of the heart and the elasticity of blood vessels, and furthermore, the time required for deceleration of the first differential wave, that is, the time required for differential wave descent (T
_S23 ) is an index that mainly represents the elasticity of blood vessels, and is data that is extremely important in medicine.

As is clear from the above description, the pulse wave measuring apparatus of the present invention has a first pulse time required for the differential pulse wave which is considered to have a deep relationship with both the blood pushing force of the heart and the elasticity of the blood vessel. The required time of the differential wave descent, or the required time of the first to third intersections or the required time of the second to third intersections of the twice differential pulse wave is measured, and the measurement result is determined using the pulse rate of the subject. Correction calculation can be performed to a value equivalent to the measurement at the reference pulse rate, so that it is possible to eliminate variations in evaluation caused by fluctuations in pulse rate, and to absorb individual differences due to differences between subjects, and All the measurement results on the blood circulation state and the vascular elasticity can be uniformly compared and evaluated.

[0029]

[0030]

[Brief description of the drawings]

FIG. 1 is a block diagram of a pulse wave measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a waveform chart showing an example of a differentiated pulse wave and a twice-differential pulse wave for explaining a basic operation of the pulse wave measuring device.

FIG. 3 is a waveform diagram showing another example of a differentiated pulse wave and a twice-differential pulse wave for explaining a basic operation of the pulse wave measuring device.

FIG. 4 is a waveform diagram of a differential pulse wave for explaining an operation of a pulse rate correction calculation by the pulse wave measuring apparatus.

FIG. 5 is a block diagram of a pulse wave measuring apparatus according to the second embodiment.

FIG. 6 is a block diagram of a pulse wave measuring apparatus according to the third embodiment.

FIG. 7 is a block diagram of a pulse wave measuring apparatus according to a fourth embodiment.

FIG. 8 is a waveform diagram of an acceleration pulse wave waveform for describing an index calculation method of the conventional pulse wave measuring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pulse wave sensor 2 Differential processing part 3 Rise point detection part 4 Incline zero point detection part 5 Differentiation first wave required time detection part 6 Pulse rate detection part 7 Pulse rate correction calculation part 10 Maximum point detection part 11 Differential wave descent required time Detector 12 Second derivative processor 13 Intersection detector 14 First to third intersection required time detector 15 Second to third intersection required time detector

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) A61B 5/02

Claims (4)

(57) [Claims] 1. A pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a differential processing unit for differentiating an output of the pulse wave sensor, and a time position of a rising point of a waveform obtained by the differentiation. A rising point detecting section for detecting, a slope 0 point detecting section for detecting a temporal position of a point where the rising waveform decreases after passing through the maximum point and the slope becomes 0, and from the rising point until reaching the slope 0 point A first-wave required time detecting unit for detecting the required time of the subject;
A pulse rate detector for counting the pulse rate
And a predetermined reference pulse for the time required for the first differential wave
Pulse rate correction that calculates the correction to a value equivalent to the measurement in number
A pulse wave measurement device including a calculation unit. 2. A pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a differential processing unit for differentiating the output of the pulse wave sensor, and a waveform obtained by the differentiation reaches a maximum after rising. A maximum point detector for detecting the temporal position of the point, a zero point detector for detecting the temporal position of a point that decreases after passing through the maximum point and has a slope of 0, and a slope from the maximum point. A differential wave descent time detection unit for detecting a descent time required for the waveform to reach point 0, and a pulse rate of the subject
A pulse rate detector for counting the number of pulses.
Based on the number of beats, the prescribed criteria for the time required for differential wave descent
Pulse rate corrected to a value equivalent to the pulse rate measurement
A pulse wave measurement device including a correction calculation unit. 3. A pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a twice differentiation processing unit for performing twice differentiation processing of the output of the pulse wave sensor, and a waveform obtained by the second differentiation is used as a reference. An intersection detector for detecting a temporal position of a point intersecting the line, and a first to third intersection required time detector for detecting a required time from a first intersection to a third intersection of a waveform obtained by the intersection detector And a pulse rate test to count the subject's pulse rate
And a first part based on the pulse rate obtained thereby.
For the required time of 3 intersections, set this to a predetermined reference pulse rate.
Pulse rate correction calculation to correct the value corresponding to the measurement in the measurement
Pulse wave measuring device provided with a part. 4. A pulse wave sensor for detecting an increase or decrease in blood volume at a fingertip, an earlobe, or the like, a twice differentiation processing unit for performing twice differentiation processing on the output of the pulse wave sensor, and a waveform obtained by the second differentiation is used as a reference. An intersection detection unit for detecting a temporal position of a point intersecting with the line, and a second to third intersection required time detection for detecting a required time from a second intersection to a third intersection of a waveform obtained by the intersection detection unit And the pulse rate to count the subject's pulse rate
It has a detection unit, and based on the pulse rate obtained by this,
Or a predetermined reference pulse for the value of the time required for the second and third intersections.
Pulse rate correction that calculates the correction to a value equivalent to the measurement in number
A pulse wave measurement device including a calculation unit.