KR102373864B1 - Apparatus and method for continuously measuring blood pressure over a long period of time without cuff - Google Patents

Abstract

A blood pressure measuring device of the present invention includes: a heart rate measuring device for measuring a heart rate (HR) of a user in a supine position; Pre-specified, multiple body parts of a user in a supine position using an electrical bio-impedance or ultrasound volume pulse wave sensor designed to be relatively insensitive to the user's intermittent movement and resulting changes in the attachment state of the sensor a pulse wave measuring device that acquires simultaneous measurement and time-synchronized pulse waves in the arteries of a brachial artery diastolic blood pressure estimator for estimating the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured by the pulse wave measuring device and the heart rate (HR) measured by the heart rate measuring device; and the systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured by the pulse wave measuring device and the diastolic blood pressure (DBP _up ) in the brachial artery estimated by the brachial artery diastolic blood pressure estimator. It includes an estimating brachial systolic blood pressure estimator, and by estimating and determining the user's blood pressure in a supine position in consideration of the difference in blood vessel characteristics and blood pressure level according to the user's body parts, non-invasive blood pressure measurement is continuously performed for a long time without a cuff. can be performed with

Description

Apparatus and method for continuously measuring blood pressure for a long time without a compression band

The present invention relates to a blood pressure measuring device and method, and more particularly, to a blood pressure measuring device and method that enables non-invasive brachial artery blood pressure measurement continuously for a long time without a compression band from a user in a supine position. .

Due to the continuous increase in the number of hypertensive patients due to the aging population, the number of people suffering from hypertension in Korea has exceeded 11 million as of 2017. The prevalence of masked hypertension in Korea is estimated to be about 10%.

Therefore, in order to accurately diagnose high blood pressure and determine management/treatment policy, hospitals currently provide the user's blood pressure for 24 hours for patients who are diagnosed with hypertension for the first time, hypertensive patients whose blood pressure is not well controlled, and patients with suspected nocturnal hypertension. The pattern is being monitored, and for this purpose, a 24-hour ambulatory blood pressure monitoring (ABPM) method is used.

In this 24-hour active blood pressure measurement (ABPM) method, the user's brachial artery blood pressure is intermittently measured by tightening the cuff, but every 15 to 20 minutes during the day and every 30 to 60 minutes at night. Periodically measure the user's non-invasive brachial blood pressure.

However, the conventional ABPM method has the following problem when measuring nighttime blood pressure from a user in a supine position (eg, a sleeping user) by using a compression band.

1) Sleep disturbance due to pressure/tenderness and noise/vibration generated during the process of repeatedly contracting the compression band

2) Distorted measurement of nocturnal blood pressure due to sleep disturbance

3) Impossible to monitor sudden blood pressure change by intermittent night blood pressure measurement every 30-60 minutes

4) Occurrence of petechiae/ecchymosis (bruising) due to repeated compression of the cuff

For this reason, the conventional ABPM method has a problem in that it is difficult to diagnose and manage/treat hypertension through accurate nighttime blood pressure monitoring, and it is difficult to satisfy user convenience as well.

Therefore, in order to improve this problem, methods for estimating non-invasive brachial blood pressure continuously for a long time without a cuff (cuff-less) have been developed.

These conventional methods are largely based on a method based on pulse transit time (PTT) or pulse wave velocity (PWV) (Method 1), and pulse wave analysis (PWA). It can be classified into one method (Method 2) and a method based on pulse wave decomposition (PWD) (Method 3), and each has advantages/disadvantages.

Therefore, most of the existing patents for measuring non-invasive brachial blood pressure without a cuff use one or more of the PWA, PWD, and PTT (or PWV)-based blood pressure estimation methods, and additionally each existing The unique method proposed by the patent aims to measure blood pressure in the brachial artery non-invasively without a cuff.

For example, Korean Patent Publication No. 10-2017-0073051 (first patent) discloses a method and apparatus for calculating blood pressure without a cuff using PTT or PWA, and Korean Patent Publication No. 10-2016-0146394 (No. 2) and Korean Patent Publication No. 10-2020-0054719 (3rd patent) disclose a method and apparatus for estimating blood pressure without a cuff using PTT or PWV.

However, in the case of the first patent, 1) pulse wave information (pulse wave waveform for PTT or PWA measured at two different points in the arterial system) is measured in the user's body, and 2) user's body information (user's gender) is measured. , age, height, weight, BMI, posture, pulse wave information, etc.) to obtain the user's estimated basic blood pressure (systolic blood pressure or diastolic blood pressure), and 3) a blood pressure correction value from the pulse wave information using the learned estimator. After determining , 4) finally applying the blood pressure correction value to the basic blood pressure to calculate the final blood pressure. In obtaining the blood pressure correction value, 1) estimating the user's posture, 2) arm At the same time measuring the pulse wave information in a plurality of position (posture) states such as lifting or lowering the 3) Determine (at least one) parameter of a regression equation for estimating the blood pressure correction value from the pulse wave information based on the pulse wave information measured at the plurality of positions (postures) and the blood pressure correction values By doing so, the blood pressure correction value is calculated. However, the first patent uses a posture change method of raising or lowering an arm above the head when performing a posture change method for generating a change in hydrostatic pressure. In the case of lowering or lowering, the pulse wave information is distorted as axial stress, vessel torsion, and bending occur in the blood vessels in the aortic arch-brachial artery section. exist.

In addition, in the second and third patents, PTT or PWV is calculated through pulse wave measurement (or pulse wave and ballistic measurement) at two different points in the arterial system, and the PTT or PWV is used to calculate blood pressure without a cuff. It relates to a method and apparatus for estimating , and the second and third patents commonly use a photoplethysmography sensor when measuring a pulse wave to calculate PTT (or PWV) at two points in the arterial system. The sensor has a disadvantage in that it is very sensitive to changes in the optical interface between the measuring part and the sensor. Accordingly, if the user moves the body even a little while measuring the pulse wave, the optical volume between the photoplethysmography sensor and the measuring part As the interface changes irreversibly, the measurement stability is poor, such as not measuring the pulse wave itself or measuring the capillary pulse wave instead of the arterial pulse wave, making it difficult to reliably measure the pulse wave for a long time.

Meanwhile, in the second patent, the blood pressure-PTT (or PWV) relationship is significantly changed by the constriction/relaxation action of blood vessels according to the activity of the sympathetic nervous system. ) Since the diastolic blood pressure and the systolic blood pressure are estimated based on the PTT (or PWV), there is a further problem that the accuracy is lowered and frequent correction is required.

1. Republic of Korea Patent Publication No. 10-2017-0073051, publication date: 2017. 06. 28, method and apparatus for calculating blood pressure 2. Republic of Korea Patent Publication No. 10-2016-0146394, publication date: December 21, 2016, blood pressure measuring device and its operating method 3. Korean Patent Publication No. 10-2020-0054719, publication date: May 20, 2020, method and apparatus for detecting blood pressure calibration time

Accordingly, an object of the present invention is to provide a blood pressure measuring device and method capable of accurately measuring blood pressure even at night without disturbing a user's sleep by enabling non-invasive blood pressure measurement to be continuously performed for a long time without a cuff.

Another object of the present invention is to provide a blood pressure measuring device and method capable of increasing user convenience and satisfaction because there is no discomfort and petechiae/ecchymosis due to repeated compression for a long time.

In addition, in the process of initializing the blood pressure-PTT (or PWV) relational expression in order to estimate blood pressure using PTT (or PWV) obtained by simultaneously measuring pulse waves in the arteries of different body parts of a user in a supine position, By using the posture change method that does not change the blood pressure-PTT (or PWV) relational expression corresponding to the blood vessel characteristics, an accurate blood pressure-PTT (or PWV) relation can be obtained, thereby improving the accuracy and reliability of the blood pressure measurement result An object of the present invention is to provide a blood pressure measuring device and a method therefor.

In addition, the present invention improves measurement stability and reliability for a long time by using a bioimpedance or ultrasonic plethysmography sensor, which is designed to be relatively insensitive to the user's intermittent movement and the resulting change in the attachment state of the sensor compared to the photoplethysmography wave. An object of the present invention is to provide a blood pressure measuring device capable of measuring a pulse wave and a method therefor.

In order to achieve the above object, a blood pressure measuring device provided by the present invention includes: a pulse wave measuring device for measuring a pulse wave from an artery of a predetermined, plurality of body parts of a user in a supine position; a brachial artery diastolic blood pressure estimator for estimating the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the heart rate (HR) of the user in the supine position and the pulse wave measured by the pulse wave measuring device; and systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured by the pulse wave measuring device and the diastolic blood pressure (DBP _up ) in the brachial artery estimated by the brachial diastolic blood pressure estimator. It is characterized in that it comprises a brachial artery systolic blood pressure estimator to estimate.

Preferably, the pulse wave measuring device includes first and second body parts for measuring the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position, and the brachial artery pulse wave transmission velocity of the user in the supine position ( PWV _ff,up ) attached to each of the third and fourth body parts for measuring an electrical bio-impedance or ultrasound (ultrasound) volume pulse wave that measures an arterial pulse wave of the corresponding part It may be a sensor.

Preferably, the brachial artery diastolic blood pressure estimator includes: a receiver configured to receive the pulse waves measured in the first and second body parts by the pulse wave measuring device; a calculation unit for receiving the pulse waves measured from the first and second body parts from the receiving unit and calculating a central artery pulse wave transmission velocity (PWV _ff,c ) and a heart rate (HR) of the user in the supine position; a model manager for initializing, correcting, storing and managing a central artery diastolic blood pressure determination model for determining a central artery diastolic blood pressure (DBP _c ) in the supine position; an inspection unit for examining a change in vascular characteristics of the central artery; The central artery diastolic blood pressure (DBP _c ) of the user in the supine position is estimated based on the received pulse wave, the heart rate (HR), and the central artery diastolic blood pressure determination model, and the supine position is based on the test result of the examination unit. a central arterial diastolic blood pressure determining unit for determining a user's central artery diastolic blood pressure (DBP _c ); a brachial artery diastolic blood pressure determination unit for determining the brachial artery diastolic blood pressure (DBP _up ) of the user in the supine position based on the central artery diastolic blood pressure (DBP _c ); and a controller for controlling operations of the receiver, the calculator, the model manager, the tester, the central artery diastolic blood pressure determiner, and the brachial diastolic blood pressure determiner based on a preset control algorithm.

Preferably, the blood pressure measuring device further comprises a heart rate measuring device for measuring a heart rate (HR) of the user in a supine position, and the brachial artery diastolic blood pressure estimator is measured in the first and second body parts by the pulse wave measuring device. a receiver for receiving the measured pulse wave and the heart rate (HR) measured by the heart rate measuring device; a calculation unit for receiving the pulse waves measured from the first and second body parts from the receiving unit and calculating a central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position; a model manager for initializing, correcting, storing and managing a central artery diastolic blood pressure determination model for determining a central artery diastolic blood pressure (DBP _c ) in the supine position; an inspection unit for examining a change in vascular characteristics of the central artery; The central artery diastolic blood pressure (DBP _c ) of the user in the supine position is estimated based on the received pulse wave, the heart rate (HR), and the central artery diastolic blood pressure determination model, and the supine position is based on the test result of the examination unit. a central arterial diastolic blood pressure determining unit for determining a user's central artery diastolic blood pressure (DBP _c ); a brachial artery diastolic blood pressure determination unit for determining the brachial artery diastolic blood pressure (DBP _up ) of the user in the supine position based on the central artery diastolic blood pressure (DBP _c ); and a controller for controlling operations of the receiver, the calculator, the model manager, the tester, the central artery diastolic blood pressure determiner, and the brachial diastolic blood pressure determiner based on a preset control algorithm.

Preferably, the central artery diastolic blood pressure determining unit converts the estimated central artery diastolic blood pressure (DBP _c ) to the user's central artery diastolic blood pressure (DBP _c ) when there is no change in the central artery blood vessel characteristics of the user as a result of the examination by the examination unit The process of determining and estimating the user's central artery diastolic blood pressure (DBP _c ) based on the central artery diastolic blood pressure determination model corrected by the model manager when there is a change in the central artery blood vessel characteristics of the user as a result of the examination by the inspection unit can be further performed.

Preferably, the model manager obtains from the pulse wave measuring device, the heart rate measuring device, and the brachial reference blood pressure monitor without changing the user's posture when it is determined by the test unit that the vascular characteristics of the user's central artery have changed. current data including one body signal, the central arterial diastolic blood pressure (DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the cardio-ankle vascular index (CAVI ₀ ); and a body signal obtained from a user in a supine position through the pulse wave measuring device, the heart rate measuring device, and the brachial reference blood pressure monitor in the process of initializing or immediately before the initialization of the central arterial diastolic blood pressure determination model, the central arterial diastolic blood pressure Based on previous data including (DBP _c ), central artery pulse wave transmission velocity (PWV _ff,c ), and the cardiac-ankle vascular index (CAVI ₀ ), the central artery diastolic blood pressure determination model may be updated and corrected. .

Preferably, the brachial artery systolic blood pressure estimating unit includes pulse waves measured at the third and fourth body parts of the user in the supine position by the pulse wave measuring device, and the brachial artery diastolic blood pressure (DBP) determined by the brachial artery diastolic blood pressure estimator. _up ) receiving unit; The brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position is calculated using the received pulse wave, and the brachial artery pulse wave transmission velocity (PWV _ff ,up ) of the user and the brachial diastolic blood pressure (DBP) are calculated. _up ) based on the arterial stiffness index (β ₀ when using brachial artery internal diameter information, α ₀ when using brachial artery internal cross-sectional area information), the brachial artery diastolic blood pressure (DBP _up ), and the arterial stiffness index ( β ₀ or α ₀ ), and the first inner diameter/ that is the brachial artery inner diameter/cross-sectional area (d _d /A _d ) at the diastolic blood pressure level measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ) is determined Calculation of calculating the second inner diameter/cross-sectional area (d _ref /A _ref ), which is the brachial artery diameter/cross-sectional area (d _ref /A _ref ) at a specific blood pressure level corresponding to 100 mmHg, based on the cross-sectional area (d _d /A _d ) wealth; The arterial stiffness index (β ₀ or α ₀ ), the second inner diameter/cross-sectional area (d _ref /A _ref ), and the systolic blood pressure level measured at the same time point as when the systolic blood pressure of the brachial artery is calculated. Brachial artery systolic determining the brachial systolic blood pressure (SBP _up ) of the user in the supine position based on the third internal diameter/cross-sectional area (d _s /A _s ), which is the brachial artery internal diameter/cross-sectional area (d _s /A _s ) blood pressure determining unit; and a controller for controlling operations of the receiver, the calculator, and the brachial systolic blood pressure determiner based on a preset control algorithm.

Meanwhile, in order to achieve the above object, the method for measuring blood pressure provided by the present invention includes: a pulse wave measuring step of measuring a pulse wave from an artery of a predetermined, plurality of body parts of a user in a supine position; a heart rate measuring step of measuring a heart rate (HR) of a user in a supine position; a brachial artery diastolic blood pressure estimating step of estimating the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured in the pulse wave measuring step and the heart rate (HR) measured in the heart rate measuring step; and systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured in the pulse wave measuring step and the diastolic blood pressure (DBP _up ) in the brachial artery estimated in the brachial artery diastolic blood pressure estimation step. It is characterized in that it comprises a step of estimating brachial systolic blood pressure.

Preferably, the step of measuring the pulse wave includes first and second body parts for calculating the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position, and the brachial artery pulse wave transmission velocity (PWV) of the user in the supine position. _ff,up ) is measured in the third and fourth body parts for calculating the bioimpedance (electrical bio-impedance) or ultrasound (ultrasound) volume pulse wave (arterial volume) attached to the first to fourth body parts A pulse wave) sensor can be used to measure the pulse wave of each part.

Preferably, the step of estimating the brachial diastolic blood pressure comprises: initializing a central artery diastolic blood pressure determination model for initializing a central artery diastolic blood pressure determination model for determining the central artery diastolic blood pressure (DBP _c ) of the user in the supine position; After calculating the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position using the pulse waves measured in the first and second body parts, the central artery pulse wave transmission velocity (PWV _ff ) of the user in the supine position a central artery diastolic blood pressure estimation step of estimating the diastolic blood pressure (DBP _c ) in the central artery of the user in the supine position by applying the _{, c} ) and heart rate (HR) to the central artery diastolic blood pressure determination model; an examination step of examining and determining whether the central artery blood vessel characteristics of the user in the supine position have changed; a central artery diastolic blood pressure determining step of determining the estimated blood pressure as the central artery diastolic blood pressure (DBP _c ) of the user in the supine position when there is no change in vascular characteristics in the central artery of the user in the supine position; and a brachial artery diastolic blood pressure determining step of determining the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the determined central artery diastolic blood pressure (DBP _c ) of the user in the supine position. .

Preferably, in the step of initializing the central artery _diastolic blood pressure determination model, the first and Obtain the intravascular diastolic pressure (Local DP _c,position1 ) of each point of the central artery between the second body parts, and the central artery pulse wave transmission velocity (PWV _ff, in the central artery section between the first and second body parts) _{c, position1} ) and a first step of measuring the heart rate (HR _position1 ); Based on the brachial artery diastolic blood pressure (DBP _up,position2 ) measured through the brachial reference blood pressure monitor in the second posture of the preset posture change method, in the blood vessels at each point of the central artery between the first and second body parts Obtaining diastolic pressure (Local DP _c,position2 ), and measuring the central artery pulse wave transmission velocity (PWV _{ff,c,position2} ) and heart rate (HR _position2 ) in the central artery section between the first and second body parts second step; and intravascular diastolic pressure (Local DP _c,position1 & Local DP _c,position2 ) at each point of the central artery in the first and second steps, and the central artery pulse wave transmission velocity (PWV _{ff,c,position1} & PWV _ff ) _{, c, position2} ), and a modeling step of obtaining coefficients of the central artery diastolic blood pressure determination model based on the heart rates (HR _position1 & HR _position2 ), wherein the central artery angle between the first and second body parts The intravascular diastolic pressure (Local DP _c,position1 or Local DP _c,position2 ) of the point is 'Central artery diastolic blood pressure (DBP _c ) at the brachial blood pressure measurement height in the situation where the user maintains the first or second posture _{,up,position1} or DBP _{c,up,position2} )' and 'the difference in hydrostatic pressure between each point of the central artery between the first and second body parts and the point of the central artery at the height of the brachial blood pressure measurement'. It may be an intravascular diastolic pressure at each point of the central artery between the first and second body parts.

Preferably, the posture change method changes the posture of the user in a direction that generates only a difference in hydrostatic pressure while not generating or minimizing axial stress in the central artery, torsion/bending of blood vessels, and changes in heart rate (HR). can change

Preferably, the step of estimating the brachial diastolic blood pressure may further include a central artery diastolic blood pressure determination model correction step of correcting the central artery diastolic blood pressure determination model when there is a change in vascular characteristics in the central artery of the user in the supine position. can

Preferably, the step of correcting the central artery diastolic blood pressure determination model includes an updating step of updating the central artery diastolic blood pressure determination model, wherein the updating step includes the pulse wave measuring device and the heart rate measurement without changing the posture of the user who is the supine posture. device, and the body signals obtained from the user through the brachial reference blood pressure monitor, the central artery diastolic blood pressure (DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the cardiac-ankle vascular index ( current data including CAVI ₀ ); and the central arterial diastolic blood pressure ( DBP _c ), the central artery pulse wave propagation velocity (PWV _ff,c ), and the cardio-ankle vascular index (CAVI ₀ ), the coefficient of the central artery diastolic blood pressure determination model may be updated based on previous data. .

Preferably, in the step of estimating brachial systolic blood pressure, brachial artery pulse wave transmission is calculated using the pulse waves measured at the third and fourth body parts to calculate the brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position. speed calculation step; _{Arterial stiffness} index ( brachial artery stiffness index calculation step of calculating β ₀ when using brachial artery internal diameter information, and α ₀ when using brachial internal cross-sectional area information; The brachial artery diastolic blood pressure (DBP _up ), the arterial stiffness index (β ₀ or α ₀ ), and the brachial artery inner diameter at the diastolic blood pressure level measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ) is determined Based on the first internal diameter/cross-sectional area (d _d /A _d ) which is /cross-sectional area (d _d /A _d ), the second is the brachial artery diameter/cross-sectional area (d _ref /A _ref ) at a specific blood pressure level corresponding to 100 mmHg. 2 A brachial artery inner diameter or cross-sectional area calculation step of calculating the inner diameter/cross-sectional area (d _ref /A _ref ); and the arterial stiffness index (β ₀ or α ₀ ), the second inner diameter/cross-sectional area (d _ref /A _ref ), and the systolic blood pressure level measured at the same time point at which the systolic blood pressure of the brachial artery is to be calculated. Brachial artery that determines the brachial systolic blood pressure (SBP _up ) of the user in the supine position based on the third internal diameter/cross-sectional area (d _s /A _s ), which is the inner diameter/cross-sectional area of the brachial artery (d _s /A _s ) It may include the step of determining the systolic blood pressure.

The blood pressure measuring apparatus and method of the present invention have the advantage of being able to accurately measure blood pressure even at night without disturbing the user's sleep by enabling non-invasive blood pressure measurement to be continuously performed for a long time without a cuff. In addition, the present invention has the advantage of increasing the user's convenience and satisfaction because there is no discomfort and petechiae/ecchymosis due to repeated compression for a long time. In addition, in the process of initializing the blood pressure-PTT (or PWV) relational expression in order to estimate the blood pressure using the PTT (or PWV) obtained by simultaneously measuring the pulse waves in the arteries of different body parts of the user in the supine position, By using the posture change method that does not change the blood pressure-PTT (or PWV) relational expression corresponding to the blood vessel characteristics, an accurate blood pressure-PTT (or PWV) relation can be obtained, thereby improving the accuracy and reliability of the blood pressure measurement result It has the advantage of being able to do it.

In addition, the present invention uses a bioimpedance or ultrasonic plethysmography sensor designed to be relatively insensitive to the intermittent movement of the user and the resulting change in the attachment state of the sensor, compared to the optical plethysmography wave, thereby improving measurement stability and providing reliable results for a long time. It has the advantage of being able to measure the pulse wave.

1 is a schematic block diagram of an apparatus for measuring blood pressure according to an embodiment of the present invention.
2 is a schematic block diagram of a brachial artery DBP estimator according to an embodiment of the present invention.
3 is a schematic block diagram of a brachial artery SBP estimator according to an embodiment of the present invention.
4 is a schematic flowchart of a method for measuring blood pressure according to an embodiment of the present invention.
5 is a diagram illustrating attachable positions of a pulse wave sensor for measuring blood pressure according to an embodiment of the present invention.
6 is a diagram illustrating an example of a process for estimating a brachial artery DBP in a supine position according to an embodiment of the present invention.
7 is a diagram illustrating an example of a process for initializing a central artery diastolic blood pressure determination model according to an embodiment of the present invention.
8 and 9 are diagrams for explaining an example of a method for changing a user's posture that can be adopted in a process for initializing the central artery diastolic blood pressure determination model illustrated in FIG. 7 .
10 is a diagram illustrating an example of a process for correcting a central artery diastolic blood pressure determination model according to an embodiment of the present invention.
11 is a diagram illustrating an example of a process for estimating brachial artery SBP in a supine position according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings, but it will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily practice the present invention. However, the present invention may be implemented in several different forms and is not limited to the embodiments described herein. On the other hand, in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification. In addition, even if the detailed description is omitted, descriptions of parts that can be easily understood by those skilled in the art are omitted.

Throughout the specification and claims, when a part includes a certain element, it means that other elements may be further included, rather than excluding other elements, unless specifically stated to the contrary.

1 is a schematic block diagram of an apparatus for measuring blood pressure according to an embodiment of the present invention. Referring to FIG. 1 , a blood pressure measuring device 100 according to an embodiment of the present invention includes a heart rate measuring device 110 , a pulse wave measuring device 120 , a brachial artery DBP estimator 130 , and a brachial artery SBP estimator ( 140).

The heart rate measuring device 110 measures a user's heart rate (HR). In particular, the heart rate measuring apparatus 110 measures a user's heart rate (HR) for measuring blood pressure, but measures the user's heart rate (HR) in a supine position. To this end, the heart rate measuring device 110 may apply various well-known techniques, and may be implemented by any method of a contact type or a non-contact type. Meanwhile, the blood pressure measuring apparatus 100 may not include the heart rate measuring apparatus 110 separately. In this case, the brachial artery DBP estimator 130 to be described later may calculate the heart rate HR. That is, the calculator ( 132 of FIG. 2 ) in the brachial artery DBP estimator 130 may calculate the heart rate HR by using the pulse wave measured by the pulse wave measuring device 120 .

The pulse wave measuring apparatus 120 measures a pulse wave from an artery of a user whose blood pressure is to be measured, and acquires a simultaneous measurement and time-synchronized pulse wave from an artery of the user who is in a supine position and is preset in a plurality of body parts. In particular, the pulse wave measuring device 120 includes first and second body parts (eg, carotid and aorta) for measuring the central artery pulse wave transmission velocity (PWV _ff,c ) of the user, and the brachial artery pulse wave of the user. It is attached to each of the third and fourth body parts of the brachial artery for measuring the transmission velocity (PWV _ff,up ), and the pulse wave of the corresponding part is measured. To this end, the pulse wave measuring device 120 is an electrical bio-impedance or ultrasound (ultrasound) arterial volume pulse wave sensor designed to be relatively insensitive to the user's intermittent movement and the resulting change in the attachment state of the sensor. can be implemented with Specific examples of the first to fourth body parts are illustrated in FIG. 5 to be described later.

The reason why the pulse wave measuring device 120 measures the pulse waves from the first to fourth body parts is generally compared to peripheral arteries (eg, radial and brachial arteries) and central arteries (eg, carotid and aorta). It is less affected by the vasoconstriction/relaxation action of the sympathetic nervous system and the time-dependent changes in the DBP-PWV _ff relationship. Since there is a difference between the artery and the central artery, this is to estimate the blood pressure in consideration of the difference in blood vessel characteristics and blood pressure level according to these parts of the body.

The brachial arterial diastolic blood pressure (DBP) estimator 130 is configured to determine the position of the user in the supine position based on the pulse wave measured by the pulse wave measuring device 120 and the heart rate (HR) measured by the heart rate measuring device 110 . Estimate the diastolic blood pressure (DBP _up ) in the brachial artery. To this end, the brachial artery DBP estimator 130 first estimates the diastolic blood pressure (DBP _c ) in the central artery of the user, which is the supine position, and based on the diastolic blood pressure (DBP _c ) in the central artery, the supine position Estimate the diastolic blood pressure (DBP _up ) in the brachial artery of the user. A specific configuration example of the brachial artery DBP estimator 130 is illustrated in FIG. 2 to be described later.

The brachial artery systolic blood pressure (SBP) estimator 140 calculates the pulse wave measured by the pulse wave measuring device 120 and the diastolic blood pressure (DBP _up ) in the brachial artery estimated by the brachial artery DBP estimator 130 . Based on the systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position is estimated. A specific configuration example of the brachial artery SBP estimation unit 140 is illustrated in FIG. 3 to be described later.

2 is a schematic block diagram of a brachial artery DBP estimator according to an embodiment of the present invention. 1 and 2 , the brachial artery DBP estimator 130 according to an embodiment of the present invention includes a receiver 131 , a calculator 132 , a model manager 133 , a tester 134 , and a central artery. It includes a DBP determination unit 135 , a brachial artery DBP determination unit 136 , and a control unit 137 .

The receiver 131 receives measurement data transmitted from the heart rate measuring device 110 and the pulse wave measuring device 120 . In particular, the receiver 131 receives the heart rate of a user who wants to measure blood pressure in a supine position from the heart rate measuring device 110 , and receives the pulse waves measured at the first and second body parts from the pulse wave measuring device 120 . do.

The calculator 132 receives the pulse waves measured from the first and second body parts of the user from the receiver 131 and calculates PWV _ff,c . Meanwhile, when the heart rate measuring device 110 is not used, the calculator 132 further calculates the heart rate HR from the pulse wave received by the receiver 131 .

The model manager 133 initializes and corrects a central artery diastolic blood pressure determination model for determining the central artery diastolic blood pressure (DBP _c ) of the user in the supine position, and stores and manages the central artery diastolic blood pressure determination model. In this case, the central arterial diastolic blood pressure determination model determines the relationship between the central artery diastolic blood pressure (DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the heart rate (HR) of the user in a supine position. As a modeled relational expression, the diastolic blood pressure (DBP _c ) of the central artery may be determined by measuring the PWV _ff,c and HR.

To this end, the model management unit 133 is based on the brachial artery diastolic blood pressure (DBP _up,position1 & DBP _up,position2 ) measured through the brachial artery reference sphygmomanometer in each of the first and second postures of the preset posture change method. Thus, the diastolic blood pressure (DBP _{c,up,position1} & DBP _{c,up,position2} ) and the hydrostatic pressure difference at the height of the brachial blood pressure measurement (to be clear, each point in the central artery section between the user's first and second body parts) and the diastolic pressure (Local DP _c,position1 & Local DP _c,position2 ) of each point of the central artery corresponding to the sum of the hydrostatic pressure difference between the position of the central artery at the height of the brachial blood pressure measurement, and the user's The user's central artery pulse wave transmission velocity (PWV _{ff,c,position1} & PWV _{ff,c,position2} ) is calculated using the pulse waves measured from the first and second body parts, and the heart rate (HR _position1 & HR _position2 ) is calculated. Initialization of modeling the relationship between the diastolic blood pressure (DBP _c ) of the central artery of the user in the supine position, the pulse wave transmission velocity of the central artery (PWV _ff,c ), and the heart rate (HR) with a relational expression by measuring or calculating can be done

Alternatively, the model manager 133 may receive and store and manage the diastolic blood pressure determination model from the controller 137 that has performed the series of processes.

On the other hand, the posture change method is a method of changing the user's posture in a direction to generate only a difference in hydrostatic pressure while not generating or minimizing the difference in heart rate and axial stress of the central artery, twisting/bending of blood vessels, say

Also, during the process of estimating the central artery diastolic blood pressure (DBP _c ) of the user in which the central artery DBP determining unit 135, which will be described later, is in a lying position, the model manager 133 performs a sudden sympathetic nerve by the examination unit 134 to be described later. When it is determined that a change in vascular characteristics has occurred due to vasoconstriction/relaxation caused by factors such as excitement, the diastolic blood pressure determination model is updated and corrected.

At this time, the change in the characteristics of blood vessels means that the blood vessel constriction/relaxation action occurs due to rapid sympathetic nerve excitation, etc., so that the cross-sectional area (or diameter) of blood vessels at a specific level of diastolic blood pressure decreases/increases, or at a specific level of diastolic blood pressure. It refers to a change in the amount of change in the blood vessel internal cross-sectional area (or diameter) in response to a very small blood pressure change, or a change in the diastolic blood pressure-vascular internal cross-sectional area (or diameter) relationship in a specific blood pressure range. The central arterial diastolic blood pressure determination model for determining the central arterial diastolic blood pressure (DBP _c ) of may be changed.

The inspection unit 134 inspects whether the vascular characteristics of the central artery are changed. At this time, the inspection unit 134 applies a different method to the case where a sudden and large change in the heart rate (HR) is not accompanied and the case where the sudden and large change in the heart rate (HR) is accompanied, respectively, to determine the vascular characteristics of the central artery. change can be checked.

First, when there is no sudden and large change in heart rate (HR), the inspection unit 134 calculates the relationship between the diastolic blood pressure and the internal cross-sectional area (or diameter) of the blood vessel in a specific central artery vascular section by Equation 18 (or 15) A _ref (or d) of the internal cross-sectional area (or diameter) of blood vessels at a specific blood pressure level corresponding to 100 mmHg and α ₀ (or β ₀ ), which is the arterial stiffness index obtained when the central arterial diastolic blood pressure determination model is initialized. _ref ), and the blood vessel internal cross-sectional area at the central artery diastolic blood pressure (DBP _c ) level when the vascular characteristics are not changed, calculated based on the central artery diastolic blood pressure (DBP _c ) obtained through the central artery diastolic blood pressure determination model (or diameter) A _d (or d _d ), and A _d (or d _d ), which is the internal cross-sectional area (or diameter) of blood vessels at the level of central artery diastolic blood pressure (DBP _c ) measured through an ultrasonic volumetric pulse wave sensor, are constant. When there is a difference greater than or equal to a threshold value, it is possible to examine whether the vascular characteristics have changed by using the first determination method of determining that the vascular characteristics have changed due to the vasoconstriction/relaxation action caused by rapid sympathetic nerve excitation. .

On the other hand, when there is a sudden and large change in the heart rate (HR), the inspection unit 134 subtracts the change component of the central artery diastolic blood pressure (DBP _c ) due to the sudden and large change in the heart rate (HR), and then the first By performing the same process as the determination method, it is possible to examine whether the vascular characteristics change by using the second determination method for determining that the vascular characteristics have changed due to the occurrence of vasoconstriction/relaxation action due to rapid sympathetic nerve excitation.

For example, if the current user has previously measured blood pressure using the method of the present invention, the test unit 134 may determine the heart rate (HR) and arterial stiffness index (β ₀ ) in the initialization step of the central artery diastolic blood pressure determination model. Or α ₀ ), and by comparing the current data and previous data, including the central arterial diastolic blood pressure determination model and coefficient information, it is possible to determine whether changes in vascular properties due to aging. In addition, in the process of estimating the central artery diastolic blood pressure (DBP _c ) of a user in a supine position, when a change in vascular characteristics occurs due to a vasoconstriction/relaxation action caused by a factor such as the rapid sympathetic nerve excitation, as described above, Through a method of determining whether the vascular characteristics of the user's central artery has changed, it can be determined whether the vascular characteristics of the user's central artery have changed during the process of estimating the diastolic blood pressure (DBP _C ) of the central artery. .

The central artery DBP determining unit 135 determines the central artery diastolic blood pressure of the user in the supine position based on the pulse wave and heart rate (HR) received from the receiving unit 131 and the central artery diastolic blood pressure determination model stored in the model management unit 133 . (DBP _c ) is estimated. That is, the central artery DBP determining unit 135 applies the central artery pulse wave transmission velocity (PWV _ff,c ) and the heart rate (HR) to the central artery diastolic blood pressure determination model to determine the central artery diastolic blood pressure of the user in the supine position. (DBP _c ) can be estimated.

In addition, the central artery DBP determining unit 135 finally determines the central artery diastolic blood pressure DBP _c of the user in the supine position based on the examination result of the examination unit 134 . That is, the central artery DBP determining unit 135 receives the examination result of the examination unit 134 through the control unit 137, and as a result of the examination, when there is no change in the central artery vascular characteristics of the user in a supine position, the estimated central artery The diastolic blood pressure (DBP _{c ) is determined as the central artery diastolic blood pressure (DBP c )} of the user in the supine position.

On the other hand, when there is a change in the central artery vascular characteristics of the user in the supine position, the central artery DBP determination unit 135 determines the user's supine position based on the diastolic blood pressure determination model corrected by the model management unit 133 . The process of estimating and determining the central artery diastolic blood pressure (DBP _c ) is further performed.

The brachial artery DBP determination unit 136 determines the user's brachial artery diastolic blood pressure (DBP _up ) based on the user's central artery diastolic blood pressure (DBP _c ), which is the supine position finally determined by the central artery DBP determination unit 135 . do.

The controller 137 controls the overall operation of the brachial artery DBP estimator 130 based on a preset control algorithm. That is, the control unit 137 includes the receiving unit 131 , the calculating unit 132 , the model managing unit 133 , the examining unit 134 , the central artery DBP determining unit 135 , and the brachial artery DBP determining unit based on a preset control algorithm. (136) controls each operation.

3 is a schematic block diagram of a brachial artery SBP estimator according to an embodiment of the present invention. Referring to FIGS. 1 and 3 , the brachial artery SBP estimator 140 according to an embodiment of the present invention is shown in FIG. It includes a receiver 141 , a calculator 142 , a brachial artery SBP determiner 143 , and a controller 144 .

The receiver 141 receives data transmitted from the pulse wave measuring device 120 and the brachial artery DBP estimator 130 . In particular, the receiver 141 receives the pulse waves measured at the third and fourth body parts by the pulse wave measuring device 120 , and the brachial artery of the user is the supine position estimated by the brachial artery diastolic blood pressure estimator 130 . Receives diastolic blood pressure (DBP _up ).

)에서의 상완동맥 내부 직경/단면적(d_ref/A_ref)인 제2 내부 직경/단면적(d_ref/A_ref)을 산출한다. The calculator 142 calculates data necessary to determine the brachial artery SBP under the control of the controller 144 . That is, the calculator 142 calculates the brachial artery pulse wave transmission velocity PWV _ff,up of the user in the supine position using the pulse wave received from the receiving unit 141, and the brachial artery pulse wave transmission velocity PWV _{ff, up} ) and the brachial artery stiffness index (β ₀ or α ₀ ) of the user in a supine position based on the brachial artery diastolic blood pressure (DBP _up ) estimated by the brachial artery DBP estimator 130 and received by the receiving unit 141 ) , and the first inner diameter that is the brachial artery inner diameter/cross-sectional area (d _d /A _d ) at the diastolic blood pressure level of the user in the supine position measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ) is determined. / A specific blood pressure level of a user in a supine position based on / cross-sectional area (d _d /A _d ), the brachial artery diastolic blood pressure (DBP _up ), and the brachial artery stiffness index (β ₀ or α ₀ ) (eg, 100

) calculates a second internal diameter/cross-sectional area (d _ref /A _ref ), which is the brachial artery internal diameter/cross-sectional area (d _ref /A _ref ).

The brachial artery SBP determination unit 143 determines the SBP of the brachial artery by using the data calculated by the calculation unit 142 . That is, the brachial artery SBP determination unit 143 determines the brachial artery inner diameter/cross-sectional area (d _s /A _s ) at the systolic blood pressure level of the user in the supine position measured at the same time point as the time point at which the systolic blood pressure of the brachial artery is to be calculated. ), the third internal diameter/sectional area (d _s /A _s ), the brachial artery stiffness index (β ₀ or α ₀ ), and the second internal diameter/sectional area (d _ref /A _ref ) based on the supine position Determines the systolic blood pressure (SBP _up ) of the user's brachial artery.

The controller 144 controls the overall operation of the brachial artery SBP estimator 140 based on a preset control algorithm. That is, the controller 144 controls the operations of the receiver 141 , the calculator 142 , and the brachial artery SBP determiner 143 based on a preset control algorithm.

4 is a schematic flowchart of a method for measuring blood pressure according to an embodiment of the present invention. 1 and 4 , a blood pressure measurement method according to an embodiment of the present invention is as follows.

First, in step S100 , the pulse wave measuring apparatus 120 measures a pulse wave from an artery in a body part of a user whose blood pressure is to be measured. That is, in step S100 , the pulse wave measuring apparatus 120 may acquire simultaneous measurement and time-synchronized pulse waves from arteries of a plurality of body parts of the user in a supine position. In this case, the plurality of body parts may be designated in advance.

For example, in step S100 , the pulse wave measuring device 120 may be attached to the first to fourth body parts to acquire simultaneous measurement and time-synchronized pulse waves from arteries of different body parts, the first and second The body part is a body part for measuring the user's central artery pulse wave transmission velocity (PWV _ff,c ), and may be any one of the aortic arch, the iliac artery, the femoral artery, and the carotid artery, respectively, and the third part located in the user's brachial artery and the fourth body part is a body part for measuring the user's brachial artery pulse wave transmission velocity (PWV _ff,up ), and may be any one of arterial positions within the range of the brachial artery.

In addition, the pulse wave measuring device 120 may be implemented as a bioimpedance (electrical bio-impedance) or ultrasonic (ultrasound) arterial volume pulse wave (arterial volume pulse wave) sensor, Fig. 5 shows a position to which such a pulse wave sensor can be attached. is foreshadowing

5 is a diagram illustrating attachable positions of a pulse wave sensor for measuring blood pressure according to an embodiment of the present invention. FIG. 5 (a) shows an example in which the bioimpedance/ultrasound volume pulse wave sensor is attached to the aortic arch (A), iliac artery (B ₁ ), and brachial artery (C, D), and FIG. 5 (b) shows an example in which the bioimpedance/ultrasound volume pulse wave sensor is attached to the aortic arch (A), the femoral artery (B ₂ ), and the brachial artery (C, D), and FIG. 5 (c) is the bioimpedance/ultrasound wave sensor. An example in which the volume pulse wave sensor is attached to the aortic arch (A), the carotid artery (B ₃ ), and the brachial artery (C,D) is shown.

At this time, as illustrated in FIG. 5 , the reason why the pulse wave measuring device 120 measures pulse waves from a plurality of different body parts is, in general, peripheral arteries (eg, radial and brachial arteries, etc.) versus central arteries. (e.g., carotid and aorta) are less affected by _{vasoconstriction} /relaxation of blood vessels due to sympathetic nervous system excitation, etc. On the other hand, since the systolic blood pressure differs between the peripheral arteries and the central arteries, this is to estimate the blood pressure in consideration of the differences in vascular characteristics and blood pressure levels according to these parts of the body.

Referring back to FIGS. 1 and 4 , in step S200 , the heart rate measuring device 110 measures the heart rate (HR) of the user, but when the heart rate measuring device is not used, the brachial artery DBP weight, which will be described later, is The government 130 may calculate and measure the heart rate (HR) of the user.

In step S300, the brachial artery DBP estimator 130 estimates the brachial artery DBP (DBP _up ) of the user in the supine position. That is, in step S300, the brachial artery DBP estimator 130 estimates the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the pulse wave and heart rate measured in steps S100 and S200. . A more detailed processing process for this will be described later with reference to FIGS. 6 to 10 .

In step S400, the brachial artery SBP estimator 140 estimates the brachial artery SBP (SBP _up ) of the user in the supine position. That is, in step S400 , the brachial artery SBP estimating unit 140 based on the pulse wave measured in step S100 and the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position estimated in step S300. The systolic blood pressure (SBP _up ) in the brachial artery of the user in the lying position is estimated. A more detailed processing process for this will be described later with reference to FIG. 11 .

6 is a diagram illustrating an example of a processing process for estimating a user's brachial artery DBP in a supine position according to an embodiment of the present invention. Referring to FIGS. 2, 4 and 6 , a process ( S300 ) for estimating the brachial artery DBP in a supine position according to an embodiment of the present invention is as follows.

First, in step S310 , the model manager 133 initializes a central artery DBP determination model for determining the central artery diastolic blood pressure (DBP _c ) of the user in the supine position. At this time, the central artery DBP determination model uses the feature that there is no or very small difference in hydrostatic pressure on the vascular path for measuring the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the lying position when the user is lying down, step In S310, according to the above characteristics, the relationship between DBP _c - HR & PWV _ff,c in the central artery is calculated by Equation 1 (linear function model), Equation 2 (quadratic function model), and Equation 3 (exponential function) model) can be modeled. Prior to performing the description of the equation, the central artery diastolic blood pressure (DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), the brachial artery diastolic blood pressure (DBP _up ), which have been used for the description of the present invention so far ), brachial artery pulse wave transmission velocity (PWV _ff,up ), and heart rate (HR) are basically variables in a situation where the user maintains a supine position. In order to distinguish between supine) and a tilted/tilted posture, words representing the user's posture state, such as supine and tilted, are added to the subscripts of the above variables.

At this time, BP_b is a predetermined constant, and HR _init,supine is the heart rate measured in the supine position at the very beginning of the phase of determining the diastolic blood pressure of the central artery from the user in the supine position (the position may depend on the use scenario). When performing the change method, it can be defined as the heart rate measured in the supine position).

Meanwhile, in order to initialize the coefficients c1, c2, and c3 of Equations 1 to 3, the model management unit 133 performs a process as illustrated in FIG. 7 .

7 is a view showing an example of a process for initializing the central artery DBP determination model according to an embodiment of the present invention. Referring to FIG. 7, first, in step S311, the model manager 133 performs the first Measure and acquire variables for initialization in posture. That is, in step S311, the model manager 133 determines the center of the brachial blood pressure measurement height based on the brachial artery diastolic blood pressure (DBP _up,position1 ) measured through the brachial artery reference blood pressure monitor in the first posture of the preset posture change method. Arterial diastolic blood pressure (DBP _{c,up,position1} ) and hydrostatic pressure differences (specifically, the central artery between the user's first and second body parts, such as the aortic arch and iliac artery, aortic arch and femoral artery, aortic arch and carotid artery, etc.) Obtaining the intravascular diastolic pressure (Local DP _c,position1 ) of each point of the central artery corresponding to the sum of the hydrostatic pressure difference between each point in the section and the position of the central artery at the height of the brachial blood pressure measurement), and the first and second Measure the central artery pulse wave transmission velocity (PWV _{ff,c,position1} ) and heart rate (HR _position1 ) in the central artery section between body parts.

Next, in step S312, the model management unit 133 measures and obtains a variable for initialization in the second posture. That is, in step S312, the model management unit 133 determines the center of the brachial blood pressure measurement height based on the brachial artery diastolic blood pressure (DBP _up,position2 ) measured through the brachial artery reference blood pressure monitor in the second posture of the preset posture change method. Arterial diastolic blood pressure (DBP _{c,up,position2} ) and hydrostatic pressure difference (specifically, the central artery between the user's first and second body parts, such as the aortic arch and iliac artery, aortic arch and femoral artery, aortic arch and carotid artery, etc.) Obtaining the intravascular diastolic pressure (Local DP _c,position2 ) of each point of the central artery corresponding to the sum of the hydrostatic pressure difference between each point in the section and the position of the central artery at the height of the brachial blood pressure measurement), and the first and second The central artery pulse wave transmission velocity (PWV _{ff,c,position2} ) and heart rate (HR _position2 ) in the central artery section between body parts are measured.

In this case, the change in the user's posture (eg, from the first posture to the second posture or from the second posture to the first posture) is the axial stress of the central artery, the torsion of the blood vessel/ It means changing the posture of the user in a direction that generates only the difference in hydrostatic pressure while not generating or minimizing the bending and the difference in heart rate.

8 and 9 are views illustrating an example of such a change in posture, and are views for explaining an example of a method of changing a user's posture that can be adopted in the process for initializing the central artery DBP determination model illustrated in FIG. 7 .

8 is an example of a tilt table-based posture change method, in which the inclination angle θ of the tilt table is changed from 0° to 30° while the user is lying on a tilt table or tilt table. It shows a method of changing the posture of the user by changing Seated-to-supine position change) A method of inducing a hydrostatic pressure difference in the vascular path of the aortic arch-carotid artery by changing the inclination angle from 90˚ to 0˚ is shown.

Referring back to FIG. 7 , the model manager 133 models the central artery DBP determination model in step S313 . That is, in step S313, the model manager 133 determines the intravascular diastolic pressure (Local DP _c,position1 & _{The central artery diastolic blood} pressure ( DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the heart rate (HR) are modeled as a relational expression.

In other words, the model manager 133 initializes the coefficients c1, c2, and c3 through two different Local DP _c - PWV _ff,c data pairs in the central artery obtained by the change in the user's posture, but c1 and a first process of obtaining the c2 coefficient, and a second process of obtaining a c3 coefficient indicating the dependence of the central artery pulse wave transmission velocity (PWV _ff,c ) on the heart rate (HR) based on the first process may be performed. .

At this time, the first process is a method for generating a hydrostatic pressure difference on the vascular path in the section measuring the central artery pulse wave transmission velocity (PWV _ff,c ), and the posture change method illustrated in FIGS. 8 and 9 . can be used However, depending on the target section, the method illustrated in Fig. 9 is not used in some cases. For example, when measuring PWV _ff,c in the aortic arch-carotid artery vascular section, Figs. All of the illustrated posture change methods may be used, but the method illustrated in FIG. 9 is not used when the PWV _ff,c is measured in the aortic arch-iliac/femoral artery section. This is because, in the sitting position, unlike the lying position, the blood vessels in the aortic arch-iliac/femoral artery section are twisted or bent, so that the c1 and c2 coefficients in Equations 1 to 3 can change as c1' and c2'. because there is

On the other hand, the process of obtaining the coefficients c1 and c2 of Equations 1 to 3 through the first process can be specified as an equation. As a practical example, PWV _ff,c is an aortic arch (AA) - Measured in the arterial section of the right femoral artery (RFA), and the central artery diastolic blood pressure determination model in the supine position, the DBP _c - HR & PWV _ff,c relational expression in the central artery corresponding to Equation 1 was obtained. In the case of using the method illustrated in FIG. 8 to generate a hydrostatic pressure difference on the vascular path of the section measuring PWV _ff,c , the process of obtaining the coefficients c1 and c2 of Equation 1 is Equation 4 to Equation 4 As exemplified in Equation 9.

At this time, PTT _ff [sec.] and PWV _ff [m/s] of Equation 4 were calculated based on the time difference between the foot feature points of two pulse waves simultaneously measured and time-synchronized at two different points in the arterial system, respectively. It is the pulse wave propagation time and the pulse wave propagation velocity, and L[m] represents the distance between two points in the arterial system. That is, the L[m] represents the distance L between the aortic arch O and the right femoral artery L ₂ in the example of FIG. 8 . In addition, DBP _c,supine [mmHg] and PTT _ff,c,supine [sec.] of Equations 5 and 6 are DBP of the central artery when the user lies on a tilt table with an inclination angle of 0˚ and It is the pulse wave transmission time in the aortic arch-right femoral artery section, and L _aa-rfa [m] represents the length of the vascular path in the aortic arch-right femoral artery section.

DP _c,aa,tilted [mmHg] and PTT _ff,c,tilted [sec.] of Equations 7 to 9 are, in the example of FIG. 8, a tilt table in a state inclined at an inclination angle of θ = 30˚ The intravascular diastolic pressure of the central artery at the height of the aortic arch (0) and the pulse wave transmission time in the aortic arch-right femoral artery section when the user is lying on the (tilt table), P _H,θ [mmHg] is A point separated by l[m] along the vascular path from the aortic arch of the user lying on a tilt table with an inclination angle of θ = 30˚ (ie, the aortic arch and h = It corresponds to the difference in hydrostatic pressure due to the difference in height between the point having a height difference of l×θ˚) and the point of the aortic arch. Among the parameters constituting the P _H,θ , ρ and g are blood density (≒1050) [kg/m ³ ] and gravitational acceleration (≒9.8) [m/s ² ], respectively, and uc is the hydrostatic pressure in Pa Corresponds to a constant of 0.00750062 value for conversion to mmHg.

In conclusion, the coefficients c1 and c2 of Equation 1 can be determined by finding a numerical solution of the simultaneous system of nonlinear equations corresponding to Equations 6 and 9 among Equations 4 to 9 above.

In addition, in situations other than the specific examples mentioned above (eg, measuring PWV _ff,c in the aortic arch-carotid artery section, using the posture change method illustrated in FIG. 9 , and central artery as in Equation 2 or Equation 3) In DBP _c - HR & PWV _ff,c, etc.), the coefficients c1 and c2 can be determined and initialized in the same way by obtaining the numerical solution of the simultaneous equations of Equations 5 and 7 above can

On the other hand, the second process is a process of initializing the coefficient c3 of Equations 1 to 3 based on the first process. The coefficient c3 of Equations 1 to 3 can be determined and initialized using the average value of the coefficient c3 indicating the dependence of the PWV _ff,c on the HR of . Alternatively, the heart rate measured in the supine position at the very beginning of the phase of determining the diastolic blood pressure of the central artery from the user in the supine position (depending on the usage scenario, the heart rate measured in the supine position when the posture change method is performed depending on the usage scenario) When HR changes above a certain threshold compared to the HR _{init,supine value} defined by Through the PWV _ff,c values in the supine position measured in the arch-iliac/femoral artery section, a personalized c3 coefficient value can be obtained.

When the central artery DBP determination model is initialized in this way, in step S320 of FIG. 6 , the central artery DBP determination unit 135 obtains from the receiver 131 and the calculation unit 132 in the central artery of the user in a supine position. DBP in the central artery is estimated by applying HR and PWV _ff ,c to the relational expression of DBP _c - HR & PWV _ff,c as in Equations 1 to 3 above. That is, in step S320, the central artery DBP determining unit 135 is measured in the first and second body parts (eg, aortic arch and iliac artery, aortic arch and femoral artery, aortic arch and carotid artery, etc.), and the receiving unit 131 ) and the user's central artery pulse wave transmission velocity (PWV _ff,c ) obtained by the calculator 132 and the user's heart rate (HR) obtained from the receiver 131 or the calculator 132 in Equation 1 to Equation 3 may be applied to the central artery diastolic blood pressure determination model to estimate the diastolic blood pressure DBP _c in the central artery of the user in the supine position.

In steps S330 and S340, the inspection unit 134 inspects and determines whether the central artery vascular characteristic of the user in the supine position has changed, and the central artery DBP determination unit 135 that has received the determination result through the control unit 137 is As a result of the determination of the inspection unit 134 , if there is no change in the central artery vascular characteristic of the user in the supine position, the estimated blood pressure is determined as the diastolic blood pressure DBP _c in the central artery of the user in step S350 . Thereafter, in step S360 , the brachial artery DBP determining unit 136 determines the diastolic blood pressure DBP _up in the user's brachial artery based on the determined diastolic blood pressure DBP _c in the central artery.

At this time, the change in the characteristics of blood vessels means that the blood vessel constriction/relaxation action occurs due to rapid sympathetic nerve excitation, etc., so that the cross-sectional area (or diameter) of blood vessels at a specific level of diastolic blood pressure decreases/increases, or at a specific level of diastolic blood pressure. It refers to a change in the amount of change in the blood vessel internal cross-sectional area (or diameter) in response to a very small blood pressure change, or a change in the diastolic blood pressure-vascular internal cross-sectional area (or diameter) relationship in a specific blood pressure range. The central arterial diastolic blood pressure determination model for determining the central arterial diastolic blood pressure (DBP _c ) of may be changed.

In steps S330 and S340, the inspection unit 134 determines whether a rapid and large change in heart rate (HR) is not accompanied and a case in which a sudden and large change in heart rate (HR) is accompanied in order to inspect and determine whether the vascular characteristics change. In each case, a different method may be applied to examine whether the vascular characteristics of the central artery are changed.

First, when there is no sudden and large change in heart rate (HR), the inspection unit 134 calculates the relationship between the diastolic blood pressure and the internal cross-sectional area (or diameter) of the blood vessel in a specific central artery vascular section by Equation 18 (or 15) A _ref (or d) of the internal cross-sectional area (or diameter) of blood vessels at a specific blood pressure level corresponding to 100 mmHg and α ₀ (or β ₀ ), which is the arterial stiffness index obtained when the central arterial diastolic blood pressure determination model is initialized. _ref ), and the blood vessel internal cross-sectional area at the central artery diastolic blood pressure (DBP _c ) level when the vascular characteristics are not changed, calculated based on the central artery diastolic blood pressure (DBP _c ) obtained through the central artery diastolic blood pressure determination model (or diameter) A _d (or d _d ), and A _d (or d _d ), which is the internal cross-sectional area (or diameter) of blood vessels at the level of central artery diastolic blood pressure (DBP _c ) measured through an ultrasonic volumetric pulse wave sensor, are constant. When there is a difference greater than or equal to a threshold value, it is possible to examine whether the vascular characteristics have changed by using the first determination method of determining that the vascular characteristics have changed due to the vasoconstriction/relaxation action caused by rapid sympathetic nerve excitation. .

When a sudden and large change in the heart rate (HR) is accompanied, the inspection unit 134 subtracts the change component of the central artery diastolic blood pressure (DBP _c ) due to the sudden and large change in the heart rate (HR), and then the first determination method By performing the same process as described above, it is possible to examine whether the vascular characteristics are changed by using the second determination method of determining that the vascular characteristics have changed due to the occurrence of vasoconstriction/relaxation action due to rapid sympathetic nerve excitation.

Meanwhile, as a result of the determination of the examination unit 134 , when there is a change in the central artery vascular characteristics of the user in the supine position, the control unit 137 controls the model management unit 133 to correct the central artery DBP determination model.

Accordingly, in step S370, the model manager 133 that has received the control corrects the central artery DBP determination model. That is, after the DBP determination models of the central artery corresponding to Equations 1 to 3 are initialized in step S310, they may undergo short-term changes due to rapid vasoconstriction/relaxation action that occurs due to sympathetic nervous system excitation, etc. When such a change is detected, in step S370 , the model manager 133 that has received the control calibrates the DBP determination model of the central artery corresponding to Equations 1 to 3 . An example of the central artery DBP determination model correction process ( S370 ) is illustrated in FIG. 10 .

10 is a view showing an example of a process for correcting the central artery DBP determination model according to an embodiment of the present invention. Referring to FIG. 10 , the central artery DBP determination model correction process (S370) is as follows. Follow the steps.

First, in step S371, the model management unit 133 calculates current data. That is, in step S371, the central artery diastolic blood pressure ( DBP _c ), central artery pulse wave propagation velocity (PWV _ff,c ), and cardio-ankle vascular index (CAVI ₀ ) are obtained.

In addition, in step S372, the model management unit 133 derives the previous data. That is, in step S372, the model management unit 133 performs the pulse wave measuring device, the heart rate measuring device, and the brachial artery reference blood pressure monitor in the previous step S310 (or step S370, which is the immediately preceding correction process) corresponding to the initialization step of the central artery DBP determination model. Acquire previous data including central artery diastolic blood pressure (DBP _c ), central artery pulse wave transmission velocity (PWV _ff,c ), and cardio-ankle vascular index (CAVI ₀ ), which are body signals obtained from users in a supine position through do.

Then, in step S373, the model management unit 133 updates the model information. That is, in step S373, the model manager 133 updates the central artery DBP determination model (ie, Equations 1 to 3) based on the current data and previous data.

For example, when a change in the central artery DBP determination model over a short time due to severe sympathetic nervous system excitement is detected during the process of determining blood pressure from a sleeping user in a supine position (S340), the central artery DBP determination model Since the above-described posture change method for waking the sleeping user cannot be performed to correct for , the model management unit 133 determines the DBP measured through the brachial artery reference blood pressure monitor at the point in time when the change in the central artery DBP determination model is detected. Based on _up , DBP _c,current is obtained from the central artery of the user in a supine position, and PWV _ff,c,current is obtained from the aortic arch-carotid artery or aortic arch-iliac/femoral artery section through a pulse wave measuring device. , CAVI _0,current is calculated and obtained from the values (DBP _c,current and PWV _ff,c,current ) (S371). And, based on the DBP _up measured by the brachial artery reference blood pressure monitor in the process of initializing the coefficients c1, c2, and c3 of Equations 1 to 3 (or the correction process immediately before), it is obtained from the central artery of the user in the supine position. CAVI _0,previous was obtained from PWV _{ff,c,previous,} obtained in the aortic arch-carotid artery or aortic arch-iliac/femoral artery section through the DBP _c,previous and pulse wave measuring device. Calculate and obtain (S372). After that, the coefficient c2 of Equations 1 to 3 is preferentially updated through the proportional expressions of CAVI _0,current and CAVI _0,previous , and then the DBP _c,current and PWV _ff,c,current are mathematically used. The coefficient c1 of Equations 1 to 3 may be updated (S373).

The correction method of the DBP determination model of the central artery in the supine position can be specified as in Equations 10 to 13 below, taking the central artery DBP determination model in the supine position of Equation 1 as an example, The same principle can be applied to the central artery DBP determination model corresponding to Equation 2 and Equation 3 as well.

Equation 10 is a general mathematical definition of CAVI ₀ , where ρ is blood density (≒1050) [kg/m ³ ], and PWV _ff [m/s] is simultaneous measurement and time synchronization at two different points in the corresponding artery section. The pulse wave transmission velocity calculated from the time difference between the foot feature points of the two pulse waves, DBP[mmHg] is the diastolic blood pressure in the relevant arterial section, P _ref (=100mmHg)[mmHg] is a fixed constant, and finally uc (=133.322) is a constant for converting DBP in mmHg to Pa.

Equations 11 to 13 specifically show the updating process of coefficients c1 and c2, which are part of the central artery DBP determination model of the above example. First, an updated value (c2 _,updated ) of the coefficient c2 of the central artery DBP determination model can be obtained by the proportional expression of Equation 11, and the coefficient c2 of the central artery DBP determination model can be obtained from Equation 11 as shown in Equation 12 After preferentially updating with the acquired updated value (c2 _,updated ), the central artery DBP determination model through the above PWV _ff,c,current and DBP _c,current values obtained in the current correction process as shown in Equation 13 By obtaining the updated values (c1 _,updated ) of the coefficient c1 of , the correction process can be performed in the supine posture without posture change such as when the coefficients c1 and c2 of Equations 1 to 3 are initialized. If the c3 coefficient needs to be corrected, the c3 coefficient may be corrected in the same manner as in the second process of the central artery DBP determination model initialization process.

On the other hand, at this time, the DBP used in the process of initializing/correcting the coefficients c1, c2, and c3 of Equations 1 to 3 is the central artery DBP at the height of the brachial blood pressure measurement. In most cases where the difference between the DBP level of the central artery at the height of the brachial blood pressure measurement and the DBP level of the brachial artery at the height of the brachial blood pressure measurement of the user who maintains it is small or small, the DBP of the central artery at the measurement height of the brachial blood pressure is measured with the brachial reference sphygmomanometer. It can be replaced with the measured DBP of the brachial artery, and the DBP (DBP _c ) of the central artery of the user in the supine position determined through the initialized/corrected Equations 1 to 3 is the DBP of the user's brachial artery in the supine position. (DBP _up ) can be used instead. However, in some special circumstances, a significant difference may occur in DBP levels of the central artery and the brachial artery of a user who maintains a supine position. In this case, the coefficients c1, c2, and c3 of Equations 1 to 3 are initialized. / To correct, convert the DBP of the brachial artery measured with the brachial arterial sphygmomanometer to the central artery DBP at the height of the brachial blood pressure measurement, or the user's central artery in the supine position determined through the initialized/corrected Equations 1 to 3 An additional/selective process is required to convert DBP (DBP _c ) into DBP (DBP _up ) of the user's brachial artery in a supine position. A function-based, central-brachial DBP transformation method may be used.

11 is a diagram illustrating an example of a processing process for estimating systolic blood pressure in the brachial artery of a user in a supine position according to an embodiment of the present invention. Since it is more greatly affected by vasoconstriction/relaxation action caused by nervous system excitation and the (time-dependent) change in the DBP-PWV _ff relationship, steps as illustrated in FIG. 11 are performed in response to this.

Referring to FIGS. 3, 4 and 11 , a process ( S400 ) for estimating brachial artery SBP in a supine position according to an embodiment of the present invention is as follows.

First, in step S410, the calculator 142 calculates the brachial artery pulse wave transmission speed. That is, in step S410 , the calculator 142 calculates the brachial artery pulse wave propagation velocity PWV _ff,up of the user in the supine position from the pulse wave received through the receiver 141 . At this time, the pulse wave is simultaneously measured and time-synchronized through bioimpedance or ultrasound (M-mode/B-mode/Doppler mode) volumetric pulse wave sensors at the third and fourth body parts of the brachial artery, and the calculator 142 ) acquires the brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position by detecting the foot feature points of the two pulse waves and calculating the time difference between the two foot feature points.

In step S420, the calculator 142 calculates the brachial artery stiffness index. That is, in step S420, the calculator 142 calculates the brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position calculated in step S410, and the supine position estimated in step S300 and received by the receiving unit 141. The arterial stiffness index (β ₀ or α ₀ ) of the brachial artery of the user in the supine position is calculated based on the user's brachial artery diastolic blood pressure (DBP _up ) in the posture.

In step S430, the calculator 142 calculates the inner diameter or cross-sectional area of the brachial artery. That is, in step S430 , the calculator 142 calculates the first brachial artery inner diameter (d _d ) at the diastolic blood pressure level of the user in the supine position measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ) is determined. Based on the internal diameter (d _d ), the brachial artery diastolic blood pressure (DBP _up ), and the arterial stiffness index (β ₀ ) of the brachial artery, the inside of the brachial artery at a specific blood pressure level (eg, 100 mmHg) of the user in the supine position Calculate the second inner diameter d _ref , which is the diameter d _ref . If it is desired to use information on the internal cross-sectional area rather than the internal diameter of the brachial artery, the calculator 142 determines the diastolic blood pressure (DBP up) of the user in the supine position measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ) is determined. Based on the first internal cross-sectional area _{(A d )} , the brachial artery diastolic blood pressure (DBP _up ), and the arterial stiffness index (α ₀ ) of the brachial artery at the blood pressure level, the supine position is A second internal cross-sectional area (A _ref ), which is the internal cross-sectional area (A _ref ) of the brachial artery at the user's specific blood pressure level (eg, 100 mmHg), is calculated.

In step S440, the brachial artery SBP determination unit 143 determines the brachial artery SBP. That is, in step S440, the brachial artery SBP determination unit 143 determines the brachial artery inner diameter (d _s ) at the systolic blood pressure level of the user in the supine position measured at the same time point as the time point at which the systolic blood pressure of the brachial artery is to be determined. Based on the third inner diameter (d _s ), the arterial stiffness index (β ₀ ) of the brachial artery, and the second inner diameter (d _ref ), the systolic blood pressure (SBP _up ) of the brachial artery of the user in the supine position is determined do. If it is desired to use information on the internal cross-sectional area rather than the internal diameter of the brachial artery, the brachial artery SBP determining unit 143 is a user who is in a supine position measured at the same time point as when the systolic blood pressure of the brachial artery is to be determined. Based on the third internal cross-sectional area (A _s ), which is the internal cross-sectional area (A _s ) of the _{brachial artery} at the systolic blood pressure level of It determines the systolic blood pressure (SBP _up ) of the user's brachial artery, which is the posture.

On the other hand, step S400 can be specified as in Equations 14 to 16 below for the case of using information on the inner diameter rather than the inner cross-sectional area of the brachial artery.

Equation 14 is a general mathematical definition of the arterial stiffness index (β ₀ , arterial stiffness index beta 0), where ρ is the blood density (≒1050) [kg/m ³ ], and PWV _ff [m/s] is the corresponding arterial section The pulse wave propagation velocity calculated from the time difference of the foot feature points of the two pulse _waves simultaneously measured and time-synchronized at two different points of The last constant, uc(=133.322), is a constant for converting DBP in mmHg to Pa. Therefore, by applying to Equation 14, PWV _ff (PWV _ff,up ) of the brachial artery in the supine position and DBP (DBP _up ) of the brachial artery in the supine position estimated in the step of estimating the DBP of the brachial artery, The arterial hardness index (β ₀ ) of the brachial artery of the user in the supine position may be calculated.

Equation 15 is an equation for calculating the inner diameter of the brachial artery (step S430), where d _d [mm] and d _ref [mm] are the inner diameter of the brachial artery and 100 mmHg of the brachial artery at the DBP blood pressure level of the brachial artery, respectively. Corresponds to the inner diameter of the brachial artery at the blood pressure level. Therefore, the β ₀ of the brachial artery calculated from Equation 14, the DBP (DBP _up ) of the brachial artery estimated in step S300 of FIG. 4 , and the DBP blood pressure level of the brachial artery of the user in the supine position obtained through the measurement. The value of d _ref of the brachial artery of the user in the supine position may be determined based on P _ref , which is a fixed constant value corresponding to the inner diameter of d _d and 100 mmHg.

Equation 16 is an equation for determining the SBP of the brachial artery (step S440), where d _s [mm] means the inner diameter of the brachial artery at the SBP blood pressure level of the brachial artery. In conclusion, d _ref of the brachial artery calculated from Equation 15, β ₀ of the brachial artery calculated from Equation 14, P _ref which is a fixed constant value corresponding to 100 mmHg, and the supine position obtained through measurement of the brachial artery of the user. The SBP value in the brachial artery of the user in the supine position may be determined based on d _s , which is the inner diameter of the brachial artery at the SBP blood pressure level.

If, in step S440, it is desired to determine the SBP using information on the internal cross-sectional area rather than the internal diameter of the brachial artery, the steps S420 to S440 and the corresponding Equations 14 to 16 are calculated using the following Equations 17 to It can be specified by changing to Equation 19.

At this time, in Equations 17 to 19, β ₀ in Equations 14 to 16 is α ₀ , and d _d /d _ref /d _s , which is a variable representing diameter information, is A _d /A _ref /A _s , respectively. It has the same process and meaning, except that it is replaced with .

Although embodiments of the present invention have been described above, the scope of the present invention is not limited thereto, and the present invention is easily changed from the embodiments by those of ordinary skill in the art to which the present invention belongs and recognized as equivalent. including all changes and modifications to the scope of

100: blood pressure measuring device 110: heart rate measuring device
120: pulse wave measuring device 130: brachial artery DBP estimator
131, 141: receiving unit 132, 142: calculating unit
133: model management unit 134: inspection unit
135: central artery DBP determinant 136: brachial artery DBP determinant
137: controller 140: brachial artery SBP estimation unit
143: brachial artery SBP determination unit 144: control unit

Claims (15)

A blood pressure measuring device comprising:
a pulse wave measuring device for measuring a pulse wave from an artery of a predetermined, plurality of body parts of a user in a supine position;
a brachial artery diastolic blood pressure estimator for estimating the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the heart rate (HR) of the user in the supine position and the pulse wave measured by the pulse wave measuring device; and
Based on the pulse wave measured by the pulse wave measuring device and the diastolic blood pressure (DBP _up ) in the brachial artery estimated by the brachial diastolic blood pressure estimator, the systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position is estimated Including a brachial systolic blood pressure estimator,
The pulse wave measuring device
First and second body parts for measuring the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position, and the brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position Blood pressure measurement, characterized in that it is an electrical bio-impedance or ultrasound (ultrasound) arterial volume pulse wave sensor attached to each of the third and fourth body parts for measuring an arterial pulse wave in the corresponding part Device. delete According to claim 1, wherein the brachial artery diastolic blood pressure estimator
a receiver configured to receive the pulse waves measured in the first and second body parts by the pulse wave measuring device;
a calculation unit for receiving the pulse waves measured from the first and second body parts from the receiving unit and calculating a central artery pulse wave transmission velocity (PWV _ff,c ) and a heart rate (HR) of the user in the supine position;
a model manager for initializing, correcting, storing and managing a central artery diastolic blood pressure determination model for determining a central artery diastolic blood pressure (DBP _c ) in the supine position;
an inspection unit for examining a change in vascular characteristics of the central artery;
Based on the received pulse wave, the heart rate (HR), and the central artery diastolic blood pressure determination model, the central artery diastolic blood pressure (DBP _c ) of the user in the supine position is estimated, and based on the test result of the examination unit, the supine position a central arterial diastolic blood pressure determining unit that determines the user's central arterial diastolic blood pressure (DBP _c );
a brachial artery diastolic blood pressure determination unit for determining the brachial artery diastolic blood pressure (DBP _up ) of the user in the supine position based on the central artery diastolic blood pressure (DBP _c ); and
and a controller for controlling each operation of the receiver, calculator, model manager, tester, central artery diastolic blood pressure determiner, and brachial diastolic blood pressure determiner based on a preset control algorithm. According to claim 1, wherein the blood pressure measuring device
Further comprising a heart rate measuring device for measuring the heart rate (HR) of the user in a supine position,
The brachial artery diastolic blood pressure estimating unit
a receiver configured to receive pulse waves measured at the first and second body parts by the pulse wave measuring device and a heart rate (HR) measured by the heart rate measuring device;
a calculation unit for receiving the pulse waves measured from the first and second body parts from the receiving unit and calculating a central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position;
a model manager for initializing, correcting, storing and managing a central artery diastolic blood pressure determination model for determining a central artery diastolic blood pressure (DBP _c ) in the supine position;
an inspection unit for examining a change in vascular characteristics of the central artery;
Based on the received pulse wave, the heart rate (HR), and the central artery diastolic blood pressure determination model, the central artery diastolic blood pressure (DBP _c ) of the user in the supine position is estimated, and based on the test result of the examination unit, the supine position a central arterial diastolic blood pressure determining unit that determines the user's central arterial diastolic blood pressure (DBP _c );
a brachial artery diastolic blood pressure determination unit for determining the brachial artery diastolic blood pressure (DBP _up ) of the user in the supine position based on the central artery diastolic blood pressure (DBP _c ); and
and a controller for controlling each operation of the receiver, calculator, model manager, tester, central artery diastolic blood pressure determiner, and brachial diastolic blood pressure determiner based on a preset control algorithm. According to claim 3 or 4, wherein the central arterial diastolic blood pressure determining unit
If there is no change in the central artery vascular characteristics of the user as a result of the examination by the inspection unit, the estimated central artery diastolic blood pressure (DBP _c ) is determined as the user's central artery diastolic blood pressure (DBP _c ),
If there is a change in the central artery blood vessel characteristics of the user as a result of the examination by the inspection unit, a process of estimating the central artery diastolic blood pressure (DBP _c ) of the user is further performed based on the central artery diastolic blood pressure determination model corrected by the model manager Blood pressure measuring device, characterized in that. The method of claim 5, wherein the model management unit
During the process of estimating the central artery diastolic blood pressure (DBP _c ) of the user in the lying position,
When it is determined by the inspection unit that the vascular characteristics of the user's central artery have changed,
The central artery diastolic blood pressure (DBP _c ) and the central artery pulse wave transmission velocity (PWV _ff,c ), which are body signals obtained from the pulse wave measuring device, the heart rate measuring device, and the brachial reference blood pressure monitor without changing the user's posture , and current data including cardio-ankle vascular index (CAVI ₀ ); and
The central arterial diastolic blood pressure ( DBP _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the central artery diastolic blood pressure determination model based on previous data including the cardiac-ankle vascular index (CAVI ₀ ) is updated and corrected. blood pressure measuring device. According to claim 1, wherein the brachial systolic blood pressure estimator
a receiver configured to receive the pulse waves measured at the third and fourth body parts of the user in the supine position by the pulse wave measuring device and the brachial diastolic blood pressure (DBP _up ) estimated by the brachial diastolic blood pressure estimator;
The brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position is calculated using the received pulse wave, and the brachial artery pulse wave transmission velocity (PWV _ff ,up ) of the user and the brachial diastolic blood pressure (DBP) are calculated. _up ), the brachial artery stiffness index (β ₀ when using brachial artery internal diameter information, α ₀ when using brachial internal cross-sectional area information) is calculated based on the user’s supine position, and the brachial artery diastolic blood pressure (DBP _up ) is calculated. ), the brachial artery stiffness index (β ₀ or α ₀ ), and the brachial artery diastolic blood pressure (DBP _up ) measured at the same time point as when determining the brachial artery inner diameter/ Based on the first internal diameter/cross-sectional area (d _d /A _d ), which is the cross-sectional area (d _d /A _d ), the brachial artery inner diameter/cross-sectional area (d _ref /A) at a specific blood pressure level corresponding to 100 mmHg of the user in the supine position a calculator for calculating a second inner diameter/cross-sectional area (d _ref /A _ref ) that is _ref );
The brachial artery stiffness index (β ₀ or α ₀ ), the second inner diameter/cross-sectional area (d _ref /A _ref ), and the supine position measured at the same time point as the time point at which the systolic blood pressure of the brachial artery is to be calculated Based on the third inner diameter/cross-sectional area (d _s /A _s ) of the brachial artery inner diameter/cross-sectional area (d _s /A _s ) at the user’s systolic blood pressure level, the user’s brachial artery systolic blood pressure (SBP _up ) in the supine position ) brachial artery systolic blood pressure determining unit to determine; and
and a controller for controlling each operation of the receiver, the calculator, and the brachial systolic blood pressure determiner based on a preset control algorithm. In the blood pressure measurement method,
a pulse wave measuring step of measuring a pulse wave from an artery of a predetermined, plurality of body parts of the user in a supine position;
a heart rate measuring step of measuring a heart rate (HR) of a user in a supine position;
a brachial artery diastolic blood pressure estimating step of estimating the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the pulse wave measured in the pulse wave measuring step and the heart rate (HR) measured in the heart rate measuring step; and
Based on the pulse wave measured in the pulse wave measuring step and the diastolic blood pressure (DBP _up ) in the brachial artery estimated in the brachial diastolic blood pressure estimation step, the systolic blood pressure (SBP _up ) in the brachial artery of the user in the supine position is estimated Including the step of estimating brachial systolic blood pressure,
The pulse wave measurement step is
First and second body parts for calculating the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position, and for calculating the brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position Measure the pulse waves in the third and fourth body parts,
A method for measuring blood pressure, characterized in that the first to fourth body parts measure the pulse wave of each part using an electrical bio-impedance or an ultrasonic arterial volume pulse wave sensor attached to the body part. . delete The method of claim 8, wherein the step of estimating the brachial artery diastolic blood pressure
a central artery diastolic blood pressure determination model initialization step of initializing a central artery diastolic blood pressure determination model for determining the central artery diastolic blood pressure (DBP _c ) of the user in the supine position;
After calculating the central artery pulse wave transmission velocity (PWV _ff,c ) of the user in the supine position using the pulse waves measured in the first and second body parts, the central artery pulse wave transmission velocity (PWV _ff ) of the user in the supine position a central artery diastolic blood pressure estimation step of estimating the diastolic blood pressure (DBP _c ) in the central artery of the user in the supine position by applying the _{, c} ) and heart rate (HR) to the central artery diastolic blood pressure determination model;
an examination step of examining and determining whether the central artery blood vessel characteristics of the user in the supine position have changed;
a central artery diastolic blood pressure determining step of determining the estimated blood pressure as the central artery diastolic blood pressure (DBP _c ) of the user in the supine position when there is no change in vascular characteristics in the central artery of the user in the supine position; and
and a brachial diastolic blood pressure determining step of determining the diastolic blood pressure (DBP _up ) in the brachial artery of the user in the supine position based on the determined central artery diastolic blood pressure (DBP _c ) of the user in the supine position. how to measure blood pressure. The method of claim 10, wherein the step of initializing the central artery diastolic blood pressure determination model comprises:
Intravascular diastole at each point of the central artery between the first and second body parts based on the brachial diastolic blood pressure (DBP _up,position1 ) measured through the brachial artery reference sphygmomanometer in the first posture of the preset posture change method. The first to acquire the pressure (Local DP _c,position1 ) and measure the central artery pulse wave transmission velocity (PWV _{ff,c,position1} ) and heart rate (HR _position1 ) in the central artery section between the first and second body parts Level 1;
Based on the brachial artery diastolic blood pressure (DBP _up,position2 ) measured through the brachial reference blood pressure monitor in the second posture of the preset posture change method, in the blood vessels at each point of the central artery between the first and second body parts Obtaining diastolic pressure (Local DP _c,position2 ), and measuring the central artery pulse wave transmission velocity (PWV _{ff,c,position2} ) and heart rate (HR _position2 ) in the central artery section between the first and second body parts second step; and
Intravascular diastolic pressure (Local DP _c,position1 & Local DP _c,position2 ) at each point of the central artery in the first and second steps, the central artery pulse wave transmission velocity (PWV _{ff,c,position1} & PWV _{ff, c, position2} ), and a modeling step of obtaining coefficients of the central artery diastolic blood pressure determination model based on the heart rate (HR _position1 & HR _position2 ),
The intravascular diastolic pressure (Local DP _c,position1 or Local DP _c,position2 ) at each point of the central artery between the first and second body parts is
In a situation in which the user maintains the first or second posture, 'Central artery diastolic blood pressure (DBP _{c,up,position1} or DBP _{c,up,position2} ) at the brachial pressure measurement height' and 'The first and second positions 2 The diastolic pressure in the blood vessels at each point of the central artery between the first and second body parts obtained by summing the difference in hydrostatic pressure between each point of the central artery between the body parts and the point of the central artery at the height of the brachial blood pressure measurement. A method for measuring blood pressure, characterized in that. The method of claim 11, wherein the posture change method
Blood pressure measurement, characterized in that the user's posture is changed in a direction to generate only a difference in hydrostatic pressure while not generating or minimizing axial stress in the central artery, torsion/bending of blood vessels, and changes in heart rate (HR) method. The method of claim 11, wherein the step of estimating the brachial artery diastolic blood pressure
When there is a change in vascular characteristics in the central artery of the user in the lying position,
The method for measuring blood pressure according to claim 1, further comprising: correcting the central arterial diastolic blood pressure determining model for correcting the central arterial diastolic blood pressure determining model. The method of claim 13, wherein the step of correcting the central artery diastolic blood pressure determination model
Including an update step of updating the central artery diastolic blood pressure determination model,
The update step is
The central artery diastolic blood pressure (DBP _c ) and the central artery pulse wave, which are body signals obtained from the user through the pulse wave measuring step, the heart rate measuring step, and the brachial reference blood pressure monitor, without a change in the posture of the user in the supine position. Current data including rate of delivery (PWV _ff,c ), and cardio-ankle vascular index (CAVI ₀ ); and
The central arterial diastolic blood pressure (DBP), which is a body signal obtained from a user in a supine position through the pulse wave measuring step, the heart rate measuring step, and the brachial reference blood pressure monitor in the process of initializing or immediately before the initialization of the central artery diastolic blood pressure determination model, the central artery diastolic blood pressure (DBP) _c ), the central artery pulse wave transmission velocity (PWV _ff,c ), and the cardio-ankle vascular index (CAVI ₀ ) based on previous data including updating the coefficient of the central artery diastolic blood pressure determination model, characterized in that how to measure blood pressure. The method of claim 8, wherein the step of estimating brachial systolic blood pressure
a brachial artery pulse wave transmission velocity calculation step of calculating a brachial artery pulse wave transmission velocity (PWV _ff,up ) of the user in the supine position by using the pulse waves measured at the third and fourth body parts;
Based on the calculated supine position, the user's brachial artery pulse wave transmission velocity (PWV _ff,up ), and the user's brachial artery diastolic blood pressure (DBP _up ), which is the supine position estimated in the brachial diastolic blood pressure estimation step, the supine position is A brachial artery stiffness index calculation step of calculating the user's brachial artery stiffness index (β ₀ when using brachial artery internal diameter information, α ₀ when using brachial internal cross-sectional area information);
The diastolic blood pressure of the user in a supine position measured at the same time point as when the brachial artery diastolic blood pressure (DBP _up ), the brachial artery stiffness index (β ₀ or α ₀ ), and the brachial artery diastolic blood pressure (DBP _up ) are determined Based on the first internal diameter/cross-sectional area (d _d /A _d ), which is the brachial artery internal diameter/cross-sectional area (d _d /A _d ) at the level, the brachial artery at a specific blood pressure level corresponding to 100 mmHg of the user in the supine position A brachial artery inner diameter or cross-sectional area calculating step of calculating a second inner diameter/cross-sectional area (d _ref /A _ref ) which is an inner diameter/cross-sectional area (d _ref /A _ref ); and
The brachial artery stiffness index (β ₀ or α ₀ ), the second inner diameter/cross-sectional area (d _ref /A _ref ), and the supine position measured at the same time point as the time point at which the systolic blood pressure of the brachial artery is to be calculated Based on the third inner diameter/cross-sectional area (d _s /A _s ) of the brachial artery inner diameter/cross-sectional area (d _s /A _s ) at the user’s systolic blood pressure level, the user’s brachial artery systolic blood pressure (SBP _up ) in the supine position ) of the brachial artery systolic blood pressure determining step.

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