KR100585848B1 - Non-invasive blood pressure measuring system using peripheral plethysmograph - Google Patents

Abstract

The present invention relates to a method and apparatus for measuring blood pressure noninvasively using peripheral vascular blood flow measurement.

Blood pressure measurement system using the peripheral blood flow measurement of the present invention, the signal detecting unit for detecting the amount of light entering the light detection element and converts it into a current; A current-voltage converter converting an output signal of the signal detector into a voltage signal; An amplifier for amplifying the output signal of the current-voltage converter; A filter unit for removing noise from an output signal of the amplifier unit; A signal conversion / transmission section for converting the output signal of the filter section into a digital signal for transmission; An arithmetic processing unit that receives an output signal of the signal conversion / transmitting unit and calculates a predetermined parameter; A display unit which displays an output signal of the signal conversion / transmission unit and the calculation processing unit; And a storage unit for storing output signals of the signal conversion and transmission unit and the calculation processing unit.

The calculation processing unit includes: first parameter detection means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point D of the reflected wave; Second parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point P of the shock wave; Third parameter detecting means for obtaining a slope (SP slop) of a straight line having the starting point of the volume pulse wave and the highest point of the shock wave; Fourth parameter detecting means for obtaining a slope DS slop of a straight line having the highest point of the reflected wave and the starting point of the next volume pulse wave; Fifth parameter detecting means for obtaining a reflection index (RI) obtained by dividing the magnitude of the shock wave by the magnitude of the reflected wave; A sixth parameter detecting means is provided for dividing the distance between the shock wave and the reflected wave by the interval between the starting points and obtaining a ratio (PD / SS ratio) in the width of one volume pulse wave.

Volumetric pulse wave, reflected wave, blood pressure measurement system

Description

Non-invasive blood pressure measuring system using peripheral plethysmograph

1A is an explanatory diagram of pulse wave propagation time (PTT).

1B is an example of an initial pulse wave.

1C is an example of the volumetric pulse wave in which the initial pulse wave and the reflected wave are synthesized.

1D is an explanatory diagram of each point of the volume pulse wave.

1E is an explanatory diagram of the reflection wave arrival time ΔT _DVP in the volume pulse wave.

1F is an explanatory diagram of a slope of a straight line having a starting point of a volumetric pulse wave and a peak of a shock wave and a slope of a straight line having a peak of a reflected wave and a starting point of the next volume pulse wave.

Figure 2 is a schematic diagram for explaining a blood pressure measurement system using the peripheral blood flow measurement according to an embodiment of the present invention.

3 is an example of detecting the volumetric pulse wave using the blood pressure measuring system of FIG. 2.

4 is an explanatory diagram of the detection of the reflected wave peak using the blood pressure measuring system of FIG. 2.

5 is the reflected wave arrival time at multiple beats.

6 is an example of detecting each point of the volume pulse wave according to the present invention.

The present invention relates to a method and apparatus for measuring blood pressure noninvasively using peripheral vascular blood flow measurement.

The most representative methods of measuring blood pressure noninvasively are auscultation method and oscillometric method. Both auscultation methods and oscillometric methods attach cuffs to the subject's upper arm, pressurize them to a pressure higher than the systolic blood pressure, block the arteries, and then slowly depressurize the blood pressure.

Auscultation is a method of detecting Korotkoff sounds caused by the opening of an artery blocked by external pressure.It requires a long-term training to measure blood pressure with auscultation method. There is a disadvantage that the accuracy can be different.

Oscillometric measurements, which are commonly used today, press the pressure of the cuff attached to the target's upper arm to a pressure higher than the systolic blood pressure to block blood vessels and then gradually reduce the pressure. Characteristic oscillation occurs, and the cuff pressure when the magnitude of the vibration waveform reaches the maximum value is determined as the pressure value closest to the average blood pressure. In general, the magnitude of the oscillation waveform of cuff pressure at systolic and diastolic blood pressure has a specific ratio with the magnitude of the vibration waveform at average blood pressure, which is called characteristic ratios. Because of the large variation (approximately 10 ~ 20%) due to various factors, an error may occur depending on the individual when a fixed characteristic ratio is applied. In addition, when measuring blood pressure using an oscillometric measurement method, it is affected by blood vessel hardness, vascular wall viscosity, pulse pressure, heart rate, condition of brachial tissue, measurement posture, characteristics and size of cuff material, and the like.

As such, both auscultation and oscillometric methods use cuffs, which cannot be remeasured until the occluded artery returns to normal. It is not suitable and the object to be measured may feel uncomfortable due to the compression by the cuff, and skin trauma may be caused. Therefore, there is a need for continuous and non-constrained measurements that solve the shortcomings of conventional non-invasive measurement methods.

Recently, a new non-invasive measurement method using a pulse transit time (PTT) is newly being studied as a representative unbound measurement method without using a cuff. The pulse wave propagation time refers to the time (PTT) from the R point of the electrocardiogram to the starting point of the volume pulse wave as shown in FIG. 1A, and in order to measure the pulse wave propagation time, an electrocardiogram measuring means and a volume pulse wave measuring means are required. Blood pressure estimation using pulse wave propagation time is a method of estimating blood pressure by using an inverse relationship between blood pressure and pulse wave propagation time. Increasing blood pressure results in higher pressure on the walls of the blood vessels, thereby reducing the vessel's distensibility and thus decreasing pulse wave transit time. Conversely, decreasing blood pressure reduces the pressure on the walls of the vessels. The extension of blood vessels is increased and thus the pulse wave delivery time is increased. However, the blood pressure measurement method using the pulse wave propagation time should use electrocardiogram measuring means and volumetric pulse wave measuring means, and furthermore, it is very complicated and inconvenient because there are several measuring points to measure the electrocardiogram.

Accordingly, a non-invasive, unconstrained, simple and convenient blood pressure measurement device that does not use a cuff and does not use an ECG measurement system is desired. In particular, there is a need for a blood pressure measuring apparatus that does not require multiple measuring means and multiple measuring points among non-binding and non-invasive measuring methods.

To this end, the present invention proposes a method and apparatus for measuring blood pressure noninvasively using only peripheral blood flow measurement. In general, peripheral blood flow measurement refers to measuring volumetric pulse wave in peripheral blood vessels such as a fingertip.

Pulse wave is a biosignal that detects the change in intraaortic pressure due to the heartbeat and propagates the pressure wave peripherally along the arterial wall. The pulse wave is formed by the heart and blood vessels. When the intraaortic pressure changes due to the heartbeat, the arterial vascular wall expands or contracts continuously. In this case, the periphery of the arterial wall is called plethysmogram (PTG), and the blood flow volume of the measurement site ( The pulse wave obtained by measuring the change in the volume of a blood vessel) is called a volume pulse. The volumetric pulse wave is formed by combining the reflected wave reflected from the branching point and the peripheral point of the arterial system to the initial blood flow waveform formed by the cardiac output. The reflected wave arrival time is the time difference from the origin of the volumetric pulse wave to the peak of the reflected wave and has a high correlation with the pulse wave propagation time. The pulse wave originating from the left ventricle of the heart progresses from the aorta to the peripheral blood vessels. The pulse wave forms the blood flow waveform during cardiac output, the characteristics of the aorta and the systemic circulation, and the branching and peripheral areas of the arterial stem. Reflects the characteristics of the vasculature system such as reflectors. The volumetric pulse wave and the reflected wave arrival time will be described in detail below.

The pulse wave originating in the left ventricle of the heart has the same shape as in FIG. 1B and is called the initial pulse wave. The initial pulse wave is generated due to the discontinuity of blood vessels such as branching from the aorta to arteries, arterioles, and the aortic valve closure, and proceeds to the periphery while forming a waveform combined with a reflected wave traveling in the opposite direction. The waveform synthesized with the reflected wave, that is, the shape of the volumetric pulse wave is shown in FIG. 1C. The shape of the normal volume pulse wave and each point will be described with reference to FIG. 1D. Meaning of each point of the volumetric pulse wave, in Figure 1d, S is the starting point (Appearance point), that is, the starting point of the pulse wave, the time when the left ventricle contracts, the aortic pressure rises rapidly and blood begins to be released into the artery rapidly to be. P is the peak of the Percussion, which is the point at which the volumetric pulse wave increases in size due to rapid blood release by deep contraction. T is called a tidal wave, and a shock wave (P) is a wave reflected at the branch point from the aorta to the artery. C is an incisura, which is when the aortic pressure is higher than the left ventricular pressure and the aortic valve closes, at which point it transitions from the systolic to diastolic. D is a redundant wave (dicrotic), which is a waveform in which the reflected wave returned from the branching point or the peripheral part of the artery overlaps. The time difference from the origin of the volumetric pulse wave to the peak of the reflected wave is defined as the reflected wave arrival time. 1E is an explanatory diagram of the reflection wave arrival time ΔT _DVP in the volume pulse wave. The reflected wave arrival time has a high correlation with the pulse wave propagation time (r = 0.70, P <0.0001). As the pulse wave propagation time decreases, the reflected wave reflected back from the arterial bifurcation and peripheral area returns more quickly within the cardiac cycle, which reduces the echo arrival time and increases the pulse wave propagation time, causing the reflected wave to return late. The reflected wave arrival time is increased. Increasing blood pressure increases the pressure delivered to the vessel wall, causing it to expand, thus reducing the extension of the vessel wall. Since the reduced vascular wall extends the pulse wave propagation time, the return time of the reflected waves generated at the branching points and peripheral parts of the arteries is shortened, thereby reducing the reflected wave arrival time. On the contrary, when the blood pressure decreases, the pressure delivered to the blood vessel wall is relatively decreased, thereby increasing the extension of the blood vessel wall and increasing the pulse wave propagation time. That is, the blood pressure and the reflected wave arrival time are inversely related to each other. The relationship between blood pressure and pulse wave propagation time can be explained by a formula introduced by Bramwell and Hill.

c ² = Δp V / Δvρ

Where c is the rate of pulse wave delivery and Δp is the change in pressure in the vessel, Δv is the volume in the vessel, V is the initial volume of the vessel, and ρ is the concentration of blood. And pulse wave delivery rate can be obtained by dividing the total length of the measurement site by the pulse wave delivery time.

c = ℓ / Δt

Where l is the total length of the measurement site and Δt is the pulse wave propagation time. In other words, when the equations 1 and 2 are combined, the pulse wave propagation time and the pressure change are inversely related to each other, and thus the reflected wave arrival time determined by the pulse wave propagation time is also inversely related to the pressure change. Peripheral artery is the most significant correlation between blood pressure and echographic arrival time, and systolic blood pressure is the most contributing factor in determining echographic arrival time in peripheral artery.

The time interval from the starting point S of the volumetric pulse wave to the highest point P of the shock wave, and the volume, in addition to the parameter of the reflected wave arrival time, which is the time interval from the starting point S of the volumetric pulse wave to the highest point D of the reflected wave. The slope of the straight line (SP slop) with the origin of the pulse wave and the peak of the shock wave, the slope of the straight line (DS slop) with the peak of the reflected wave and the origin of the next volumetric pulse wave, and the reflected wave index divided by the magnitude of the reflected wave. Reflection Index (RI), the PD / SS ratio in the width of the volumetric pulse wave, which divides the distance between the shock and reflected waves by the interval between origins, is related to blood pressure. 1F is an explanatory diagram of a slope of a straight line having a starting point of a volumetric pulse wave and a peak of a shock wave and a slope of a straight line having a peak of a reflected wave and a starting point of the next volume pulse wave.

Through this theoretical background, the present invention provides new parameters for measuring blood pressure using only peripheral blood flow measurement, and blood pressure measurement method using peripheral blood vessel measurement using the parameter to solve the shortcomings of the conventional blood pressure measurement system. And its apparatus.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a blood pressure measurement method and apparatus using peripheral blood vessel measurement, which solves the disadvantages of the conventional blood pressure measurement system.

Another technical problem to be achieved by the present invention is to provide a new parameter for measuring blood pressure using peripheral blood flow measurement.

Another technical problem to be achieved by the present invention is to provide a blood pressure measurement system using only peripheral blood flow measurement.

In order to achieve the above technical problem, the present invention has the following features.

Blood pressure measurement system using the peripheral blood flow measurement of the present invention, the signal detecting unit for detecting the amount of light entering the light detection element and converts it into a current; A current-voltage converter converting an output signal of the signal detector into a voltage signal; An amplifier for amplifying the output signal of the current-voltage converter; A filter unit for removing noise from an output signal of the amplifier unit; A signal conversion / transmission section for converting the output signal of the filter section into a digital signal for transmission; An arithmetic processing unit that receives an output signal of the signal converting / transmitting unit and detects a predetermined parameter; A display unit which displays an output signal of the signal conversion / transmission unit and the calculation processing unit; And a storage unit for storing output signals of the signal conversion and transmission unit and the arithmetic processing unit.

The calculation processing unit may include a derivative unit for receiving and differentiating an output signal of the digital filter unit; A peak detector detecting a first peak and a second peak from an output signal of the derivative; A zero point detector for detecting a point at which the output signal of the derivative passes zero points; A parameter detector which calculates a predetermined parameter from an output signal of the differential part, an output signal of the zero point detector and the peak detector; And a blood pressure calculator for calculating blood pressure from the output signal of the parameter detector.

The calculation processing unit may further include: first parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point D of the reflected wave; Second parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point P of the shock wave; Third parameter detecting means for obtaining a slope (SP slop) of a straight line having the starting point of the volume pulse wave and the highest point of the shock wave; Fourth parameter detecting means for obtaining a slope DS slop of a straight line having the highest point of the reflected wave and the starting point of the next volume pulse wave; Fifth parameter detecting means for obtaining a reflection index (RI) obtained by dividing the magnitude of the shock wave by the magnitude of the reflected wave; Sixth parameter detecting means for dividing the distance between the shock wave and the reflected wave by the interval between the starting points and obtaining a ratio (PD / SS ratio) of the width of one volume pulse wave; Among them, at least one parameter detecting means is provided.

The calculation processing means further includes at least first parameter detecting means for obtaining a time interval from the starting point S of the volumetric pulse wave to the highest point D of the reflected wave, wherein the first parameter detecting means is provided immediately before the first peak. The point passing through the zero point is the starting point of the volumetric pulse wave, and when the magnitude of the second peak is greater than zero, the point passing through the zero point immediately after the second peak is the highest point of the reflected wave, and the magnitude of the second peak is Is less than or equal to 0, the second peak point is characterized in that the peak of the reflected wave.

In addition, the blood pressure measurement system using the peripheral blood flow measurement of the present invention, the digital filter to remove noise; A derivative unit for receiving and differentiating an output signal of the digital filter unit; A peak detector detecting a first peak and a second peak from an output signal of the derivative; A zero point detector for detecting a point at which the output signal of the derivative passes zero points; A parameter calculator which calculates a predetermined parameter from an output signal of the differential part, an output signal of the zero point detector and the peak detector; And a blood pressure calculator for calculating blood pressure from the output signal of the parameter detector.

The parameter calculation unit includes: first parameter detection means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point D of the reflected wave; Second parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point P of the shock wave; Third parameter detecting means for obtaining a slope (SP slop) of a straight line having the starting point of the volume pulse wave and the highest point of the shock wave; Fourth parameter detecting means for obtaining a slope DS slop of a straight line having the highest point of the reflected wave and the starting point of the next volume pulse wave; Fifth parameter detecting means for obtaining a reflection index (RI) obtained by dividing the magnitude of the shock wave by the magnitude of the reflected wave; Sixth parameter detecting means for dividing the distance between the shock wave and the reflected wave by the interval between the starting points and obtaining a ratio (PD / SS ratio) of the width of one volume pulse wave; Among them, at least one parameter detecting means is provided.

In addition, the blood pressure measurement method using the peripheral vascular blood flow measurement of the present invention, the filtering step of filtering to remove noise from the volumetric pulse wave; A derivative step of differentiating the output signal of the filtering step; A peak detection step of detecting a first peak and a second peak from the output signal of the derivative step; A zero point detection step of detecting a point at which the output signal of the differential step passes zero point; A parameter detecting step of calculating at least one parameter from the output signal of the differential step, the output signal of the zero point detection step and the output signal of the peak detection step; And a blood pressure calculation step of calculating blood pressure from the output signal of the parameter detection step.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of the blood pressure measurement system using the peripheral blood flow measurement according to an embodiment of the present invention will be described in detail.

FIG. 2 is a schematic diagram illustrating a blood pressure measuring system using peripheral blood flow measurement according to an embodiment of the present invention, wherein the blood pressure measuring system of FIG. 2 includes a signal detector 100, a signal preprocessor 200, and a signal converter. The transmitter 300 includes a calculation processor 400, a display 500, and a storage 600.

The signal detector 100 detects the amount of light that the photodetector enters and converts it into a current to output the signal. The signal detector 100 includes an optical sensor 110 and an optical sensor driver 120. In addition, the photodetecting element of the optical sensor 110 detects the amount of light coming in and converts it into a current, and outputs the same, and outputs two output (+,-) signals in which the current flows in opposite directions.

The signal preprocessor 200 is for amplifying the output signal of the signal detector 100 and removing noise. The signal preprocessor 200 includes a current-voltage converter 210, an amplifier 220, and a filter 230. The current-voltage converter 210 converts the output signal of the signal detector 100 into a voltage signal. The amplifier 220 is for amplifying the output signal of the current-voltage converter 210 to a predetermined gain, and may be configured as a differential amplifier having a gain of 100.

The filter unit 230 removes noise from the output signal of the amplifier 220 and passes only a predetermined frequency band. Although the volume pulse wave is mainly a component of a low frequency band, since a relatively high frequency component may occur in the origin portion of the volume pulse wave depending on an individual or a pulse rate, the predetermined frequency band may be selected from 0.05 Hz to 20 Hz. You can do In particular, the filter unit 230 may be configured to pass through a second high pass filter that blocks a signal of 0.05 Hz or less and then amplifies five times and then passes a second low pass filter that blocks a signal of 20 Hz or more.

The signal conversion / transmitter 300 converts the output signal of the signal preprocessor 200 into a digital signal and transmits the signal to the operation processor 400, the display 500, and the storage 600. A D converter 310 and a signal transmitter 320 are provided.

The A / D converter 310 converts the output signal of the signal preprocessor 200 into a digital signal. The signal transmitter 320 transmits the output signal of the A / D converter 310 to the calculation processor 400, the display 500, and the storage 600. The signal transmitter 320 includes a universal asynchronous receiver transmitter (UART) port.

The signal converter / transmitter 300 may be configured as a microcontroller, and may enable A / D conversion and RS-232 communication through the microcontroller.

The calculation processing unit 400 receives the output signal of the signal conversion / transmission unit 300 to calculate a predetermined parameter in the volumetric pulse wave. The calculation processor 400 includes a digital filter 410, a derivative 430, a peak detector 440, a zero point detector 450, a parameter detector 470, and a blood pressure calculator 480.

The digital filter unit 410 receives the output signal of the signal conversion / transmission unit 300 and removes the noise again. This uses a digital filter function to remove noise that is not completely removed by the hardware. A 5th order lowpass filter that blocks signals above 20Hz and a 5th order bandpass filter that blocks 60Hz noise can be used.

The derivative unit 430 receives the output signal of the digital filter unit 410 and performs first order differentiation. In general, since the volume pulse wave is not stabilized in the base line and the waveform has a relatively small undulation, it is difficult to analyze the signal. In the present invention, the derivative part 430 that first-orders the volume pulse wave signal is used. The signal obtained by first-ordering the volumetric pulse wave signal is called velocity pulse wave. The derivative unit 430 may use a differential filter of a least-squares polynomial method (L = 5).

The peak detector 440 detects the first peak and the second peak from the output signal of the derivative 430. The first peak refers to a peak present in a region exceeding a predetermined threshold value in the output signal of the derivative portion, and the second peak is detected after the first peak and is next to the first peak.

The zero point detection unit 450 detects a point at which the output signal of the differential unit 430 passes zero point.

The parameter detector 470 includes first to sixth parameter detectors that calculate parameters by using the output signal of the differential unit 430, the output signal of the zero point detector 450, and the output signal of the peak detector 440. . The parameter detection unit 470 detects the starting point S of the volume pulse wave, the highest point P of the shock wave, the squirrel wave T, the scare C, and the highest point D of the reflected wave (FIG. 1D). The parameter used, the first parameter which is the time interval from the starting point (S) of the volumetric pulse wave to the highest point (D) of the reflected wave, the second parameter which is the time interval from the starting point (S) to the highest point (P) of the shock wave, The third parameter, the slope of the straight line (SP slop) with the origin of the volumetric pulse wave and the peak of the shock wave, the fourth parameter with the slope (DS slop) of the straight line with the peak of the reflected wave and the origin of the next volumetric wave, the magnitude of the shock wave The fifth parameter, which is the reflection index (RI) divided by the magnitude of the reflected wave, and the sixth parameter, which is the ratio (PD / SS ratio) of the width of the volume pulse wave divided by the distance between the shock wave and the reflected wave by the interval between the starting points. Find the back. In some cases, each predetermined parameter may be calculated from a predetermined number of beats, and then the average value may be taken and used. In this way, the results obtained by obtaining the first to sixth parameters by the first to sixth parameter detection means are output to the blood pressure calculator 480.

The blood pressure calculator 480 calculates diastolic blood pressure and systolic blood pressure according to the parameters and the regression equation. The regression equation is obtained in the initial setting step.

The display unit 500 displays the output signals of the signal converter 300 and the calculation processor 400. An example of data displayed by the display unit 500 is illustrated in FIG. 3. 3 is an example in which the volumetric pulse wave is actually detected using the blood pressure measuring system of FIG. 2, and FIG. 3 shows a real-time display of the original signal, which is data received from the signal converter 300, in real time. The differential signal is also displayed. In this way, the status of the measured data can be checked. At the same time, the measured systolic blood pressure value, diastolic blood pressure value, the name of the subject and the age of the measured data are input and displayed, and the data are stored in a text file. Stored at 600.

The storage unit 600 stores the output signals of the signal converter 300 and the calculation processor 400. It stores the original signal, which is the data received from the signal conversion unit 300, and receives the measured systolic blood pressure value and the diastolic blood pressure value, the name of the measurement object, the age, and the like, and stores them in a text file.

The following describes, as an example, a method for detecting the first parameter, which is a time interval from the starting point S of the volume pulse wave to the highest point D of the reflected wave, in order to explain in detail the method of detecting the parameter in the parameter detecting means.

The peak detector 440 detects two points passing zero points to the left and right of the first peak detected by the peak detector 440, and the point preceding in time becomes the starting point of the volume pulse wave, and the following point becomes the peak of the shock wave. Next, we need to detect the peak of the reflected wave. Since the shape of the reflected wave in the volumetric pulse wave varies from person to person, two cases must be considered to find the reflected wave point in the volumetric pulse wave. This will be described with reference to FIG. 4. FIG. 4 shows two cases of the volume pulse wave and the velocity pulse wave obtained by firstly dividing the volume pulse wave to find the reflected wave point in the volume pulse wave. The first is the reflection wave which increases after the swell and the point of inflection and then peaks and decreases (FIG. 4 a), and the second does not increase but reflects only a gentle bend (FIG. 4 b). In the first case, as shown in a) of FIG. 4, the second peak of the velocity pulse wave increases to a value greater than zero and then decreases to a value less than zero. In the present invention, the zero point after the second peak passes the highest point. The point passing by is detected as the highest point of the reflected wave. In the second case, when the reflected wave appears at a gentle slope as shown in b) of FIG. 4, the second peak of the velocity pulse wave does not exceed zero. In this case, the point where the second peak of the velocity pulse wave has the highest value is detected as the highest point of the reflected wave of the volume pulse wave. The time difference between the starting point of the volumetric pulse wave and the highest point of the reflected wave thus obtained is calculated. In some cases, as shown in FIG. 5, the respective reflection wave arrival times may be calculated at predetermined bits, and then the average value may be taken.

Thus, Fig. 6 shows an example of detecting each point of the volume pulse wave according to the present invention. FIG. 6 detects the starting point of the volume pulse wave, the highest point of the shock wave, and the highest point of the reflected wave in each of the five bits detected in the selected section and displays the point.

Next, the initial setting of this invention is demonstrated. The blood pressure calculator 480 obtains diastolic blood pressure and systolic blood pressure by substituting the parameters into the regression equation. The regression equation is determined at the initial setting stage of the blood pressure measuring device of the present invention for each user. Although not particularly shown in the drawing, the present invention includes an initial setting unit, and performs initial setting. In the initial setting step, the blood pressure and the parameters of the measurement target are simultaneously measured. The data of the parameters are acquired, and the regression analysis is used to obtain the regression equation of the blood pressure and the parameters. For example, if only the reflected wave arrival time is a parameter, the blood pressure and the reflected wave arrival time of the measurement target are simultaneously measured at the initial setting step, and the measurement is repeated several times, and thus the blood pressure obtained and the corresponding reflected wave arrival time are measured. The regression analysis of the data yields the regression equation for blood pressure and echo time. In the present invention, when only the reflection wave arrival time is a parameter, an example of a regression equation of systolic blood pressure is shown in Equation 3 below.

Systolic Blood Pressure = A-BΔT _DVP

However, ΔT _DVP is the reflected wave arrival time, and A and B are determined at the initial setting stage. For most measurers, A was a positive integer between 150 and 400, and B was a positive integer between 0.1 and 0.5.

In the present invention, when only the reflection wave arrival time is a parameter, an example of a regression equation of diastolic blood pressure is shown in Equation 4.

Diastolic blood pressure = C-DΔT _DVP

However, ΔT _DVP is the reflected wave arrival time, and C and D are determined at the initial setting stage. For most measurers, C is a positive integer between 80 and 200, and D is a positive integer between 0.01 and 0.3.

As such, the present invention provides new parameters for measuring blood pressure using peripheral blood flow measurement, and provides a blood pressure measurement system using only peripheral blood flow measurement using the parameters. In addition, the present invention provides a method and apparatus for measuring blood pressure using only peripheral blood flow measurement, which solves the disadvantages of the conventional and inconvenient blood pressure measuring system.

As described above, the present invention provides a blood pressure measurement method and apparatus using peripheral blood vessel measurement to solve the disadvantages of the conventional blood pressure measurement system, the present invention is a new parameter for measuring blood pressure using peripheral blood vessel measurement Provided, the present invention provides a blood pressure measurement system using only peripheral blood flow measurement.

An apparatus and method for measuring blood pressure using only peripheral blood flow measurement according to the present invention is a novel method proposed in consideration of the correlation between the arrival time of a volume pulse wave and the blood pressure, which is inconvenient compared to an oscillometric measurement method using a cuff. It has the advantage of being small, simple and easy to measure. In addition, the blood pressure measuring apparatus and method of the present invention is a non-invasive non-constrained measuring method similar to the blood pressure measuring method using the pulse wave delivery time, and because it is possible to measure only by peripheral blood flow measurement, pulse wave delivery using an electrocardiogram and volumetric pulse wave is performed. Simple and simple compared to the measurement of time.

Claims (7)

In the blood pressure measurement system using peripheral blood flow measurement, A signal detector for detecting an amount of light input by the photodetector and converting the light into a current to output the light; A current-voltage converter converting an output signal of the signal detector into a voltage signal; An amplifier for amplifying the output signal of the current-voltage converter; A filter unit for removing noise from an output signal of the amplifier unit; A signal conversion / transmission section for converting the output signal of the filter section into a digital signal for transmission; The systolic blood pressure and diastolic blood pressure are Systolic Blood Pressure = A-BΔT Diastolic Blood Pressure = C-DΔT (Where ΔT is the reflected wave arrival time, A, B, C, and D are determined at the initial setting stage, A is a positive integer between 150 and 400, B is a positive integer between 0.1 and 0.5, and C is Positive integer between 80 and 200, and D is a positive integer between 0.01 and 0.3) A calculation processing unit obtained by; A display unit which displays an output signal of the signal conversion / transmission unit and the calculation processing unit; And a storage unit for storing an output signal of the signal conversion and transmission unit and the arithmetic processing unit. The method of claim 1, wherein the operation processing unit, A derivative unit for receiving and differentiating an output signal of the digital filter unit; A peak detector detecting a first peak and a second peak from an output signal of the derivative; A zero point detector for detecting a point at which the output signal of the derivative passes zero points; A parameter detector for calculating a parameter from an output signal of the differential part, an output signal of the zero point detector and the peak detector; And a blood pressure calculator for calculating blood pressure from the output signal of the parameter detector. The method of claim 1, wherein the operation processing unit First parameter detecting means for obtaining a time interval from the starting point S of the volumetric pulse wave to the highest point D of the reflected wave; Second parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point P of the shock wave; Third parameter detecting means for obtaining a slope (SP slop) of a straight line having the starting point of the volume pulse wave and the highest point of the shock wave; Fourth parameter detecting means for obtaining a slope DS slop between the highest point of the reflected wave and the starting point of the next volume pulse wave; Fifth parameter detecting means for obtaining a reflection index (RI) obtained by dividing the magnitude of the shock wave by the magnitude of the reflected wave; Sixth parameter detecting means for dividing the distance between the shock wave and the reflected wave by the interval between the starting points and obtaining a ratio (PD / SS ratio) of the width of one volume pulse wave; Among them, at least one parameter detection means comprising a blood pressure measuring system. The method of claim 2, The calculation processing means includes at least first parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point D of the reflected wave, The first parameter detecting means, The point passing through the zero point just before the first peak is the starting point of the volume pulse wave, If the magnitude of the second peak is greater than zero, the point passing the zero point immediately after the second peak is the highest point of the reflected wave, And when the magnitude of the second peak is less than or equal to zero, the second peak point is the highest point of the reflected wave. In the blood pressure measurement system using peripheral blood flow measurement, A digital filter unit to remove noise; A derivative unit for receiving and differentiating an output signal of the digital filter unit; A peak detector detecting a first peak and a second peak from an output signal of the derivative; A zero point detector for detecting a point at which the output signal of the derivative passes zero points; A parameter calculator which calculates a parameter from an output signal of the differential part, an output signal of the zero point detector and the peak detector; Systolic and diastolic blood pressures are output from the output signal of the parameter detector. Systolic Blood Pressure = A-BΔT Diastolic Blood Pressure = C-DΔT (Where ΔT is the reflected wave arrival time, A, B, C, and D are determined at the initial setting stage, A is a positive integer between 150 and 400, B is a positive integer between 0.1 and 0.5, and C is Positive integer between 80 and 200, and D is a positive integer between 0.01 and 0.3) Blood pressure calculator for calculating the blood pressure by; Blood pressure measuring system comprising a. The method of claim 2 and 5, wherein the parameter calculation unit First parameter detecting means for obtaining a time interval from the starting point S of the volumetric pulse wave to the highest point D of the reflected wave; Second parameter detecting means for obtaining a time interval from the starting point S of the volume pulse wave to the highest point P of the shock wave; Third parameter detecting means for obtaining a slope (SP slop) of a straight line having the starting point of the volume pulse wave and the highest point of the shock wave; Fourth parameter detecting means for obtaining a slope DS slop of a straight line having the highest point of the reflected wave and the starting point of the next volume pulse wave; Fifth parameter detecting means for obtaining a reflection index (RI) obtained by dividing the magnitude of the shock wave by the magnitude of the reflected wave; Sixth parameter detecting means for dividing the distance between the shock wave and the reflected wave by the interval between the starting points and obtaining a ratio (PD / SS ratio) of the width of one volume pulse wave; Among them, at least one parameter detection means comprising a blood pressure measuring system. In the blood pressure measurement method using peripheral blood flow measurement, A filtering step of filtering to remove noise from the volumetric pulse wave; A derivative step of differentiating the output signal of the filtering step; A peak detection step of detecting a first peak and a second peak from the output signal of the derivative step; A zero point detection step of detecting a point at which the output signal of the differential step passes zero point; A parameter detecting step of calculating at least one parameter from the output signal of the differential step, the output signal of the zero point detection step and the output signal of the peak detection step; Systolic blood pressure and diastolic blood pressure are output from the output signal of the parameter detecting step. Systolic Blood Pressure = A-BΔT Diastolic Blood Pressure = C-DΔT (Where ΔT is the reflected wave arrival time, A, B, C, and D are determined at the initial setting stage, A is a positive integer between 150 and 400, B is a positive integer between 0.1 and 0.5, and C is Positive integer between 80 and 200, and D is a positive integer between 0.01 and 0.3) A blood pressure calculation step of calculating blood pressure by; Blood pressure measuring method comprising a.

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