TW201817375A - System of using electrode arrangement to perform armband-free blood pressure measurement capable of generating blood pressure information of a person under test by determining a pulse transmission time - Google Patents

Abstract

The present invention relates to an armband-free blood pressure measurement system. The blood pressure measurement system is mainly configured to detect an electrocardiographic signal of a person under test through an ECG detection module, and measure a body impedance signal of the person under test through a wearable blood pressure measurement module worn around the limb of the person under test. The obtained information is subject to a waveform comparison to find a time difference between the heart beat and the blood flow pulse of the person under test, so as to determine a pulse transmission time, thereby generating blood pressure information of the person under test.

Description

   System for measuring armless blood pressure through electrode configuration   

The present invention relates to a blood pressure measurement system, and more particularly to a system for capturing the heartbeat and pulse wave signals of a subject to perform an armless blood pressure measurement.

In order to track physical health, in recent years, simple body index measuring instruments have gradually entered the family. Among them, the most common measuring instruments are weight scales and sphygmomanometers. However, traditional sphygmomanometers that provide an armband for inflation are The measurement time is long, and it is easy to cause the subject's physical discomfort during the inflation process. As can be seen, there is still an inconvenience in using this type of blood pressure monitor.

In recent years, the development of armless blood pressure measurement is mainly based on comparing the pulse wave signals of peripheral blood vessels and the signals of the electrocardiogram to find the pulse wave transmission time, and then to evaluate the blood pressure value, which is mainly based on Sharwood-Smith put forward the principle of Pulse Transit Time (PTT) in 2006 related to changes in cardiovascular characteristics. Prior to this research, Ahlstrom proposed the use of pulse wave transmission in 2005. The method of estimating systolic blood pressure over time, and the results show an overall correlation degree as high as 0.8, which can effectively monitor the instantaneous decrease of blood pressure, because the definition of pulse wave transmission time (PTT) represents the electrocardiogram (ECG) Delay time between R wave and peripheral blood pressure wave.

Among them, the electrocardiogram (ECG) signal represents the electrical signal of the heart beat, so by measuring the ECG signal, the heartbeat waveform of the subject can be continuously obtained.

In addition, the measurement of pulse wave signals, that is, changes in blood flow in the body, can be detected through a variety of different methods. The blood flow will be affected by the systole and diastole, and the body impedance of the blood flow through the area Changes will also occur. Therefore, in theory, the pulse signal of blood flow can be detected by Impedance Plethysmography (IPG), and the impedance value of the body can be passed through the high-frequency current into the receiver. Measure the limb of the subject and measure the feedback value to obtain it.

The inventor of the present invention has thought to improve the traditional armband blood pressure monitor through the above theory, and aims to develop a blood pressure measurement system that can be performed quickly without an armband.

The invention proposes a system for measuring armless blood pressure through an electrode configuration, which is a system that can be set at a specific position on the surface of a subject's body to simultaneously obtain a subject's heart signal and pulse signal.

The invention mainly includes two main modules, including an electrocardiogram detection module and a wearable blood pressure measurement module, wherein the electrocardiogram detection module is used to be disposed on the surface of the chest of a subject to pass through Electrocardiography (ECG) to obtain the electrocardiogram waveform of the subject when the heart beats, that is, to obtain the subject's electrocardiographic signal data, and send the electrocardiographic signal data to the wearable blood pressure measurement Module for further processing.

The other module of the present invention is the wearable blood pressure measurement module, which is mainly a flexible material that is worn around a limb of the external subject, and the wearer Type blood pressure measurement module further includes two sub-modules, which are an integrated impedance sensing sub-module and a pulse wave time calculation sub-module, wherein the body impedance sensing sub-module includes a plurality of sensing electrodes To pass high-frequency constant current through parts of the limbs of the subject through each of the sensing electrodes, to measure slight changes in the resistance signal, to obtain the subject's limbs according to Impedance Plethysmography (IPG) The pulse wave waveform caused by blood flow, amplifies, demodulates, and filters the small changes in the resistance signal to generate the body impedance signal data and then the subject's integrated impedance signal data.

Wherein, the plurality of sensing electrodes of the body impedance sensing sub-module mainly include a group of I electrodes and a group of E electrodes, and the arrangement and position thereof correspond to the settings of the wearable blood pressure measurement module of the present invention. It is set at a better position on the subject's limbs. When the subject places the wearable blood pressure measurement module around his limb (such as the wrist), the wearable blood pressure measurement module should A ring is formed around the surface of the subject's wrist watch. The group of I electrodes and the group of E electrodes are located on the inner surface of the wearable blood pressure measurement module ring, that is, the surface that is close to the skin of the subject's wrist, and The group of I electrodes and the group of E electrodes are respectively arranged on the circumferential surface of the ring at antisymmetric positions and contact the skin surface of the subject. With this optimal electrode configuration position, the representative pulse wave can be obtained more accurately Changes in the body impedance signal data.

Then, a pulse wave transit time operator module in the wearable blood pressure measurement module can obtain the electrocardiographic signal signal data measured by the electrocardiogram detection module through the wearable blood pressure measurement module. The wave transit time operation sub-module can also obtain the body impedance signal data from the body impedance sensing sub-module. The wearable blood pressure measurement module can compare the heartbeat wave of the subject represented by the signal data of the electrocardiogram. And the pulse waveform of the subject represented by the body impedance signal data, and then obtain the Pulse Transit Time, which is a pulse transit time. Finally, the wearable blood pressure measurement module The systolic blood pressure and diastolic blood pressure were calculated respectively during the pulse wave transmission time to generate a blood pressure value of the subject.

The blood pressure value data is calculated by the wearable blood pressure measurement module according to the pulse wave transmission time by the following formula: Among them, PTT represents the Pulse Transit Time, P is the value of the blood pressure data, α is the adjustment constant, L is the distance of the pulse wave transmission, ρ is the blood density, d is the microvascular diameter, w Represents the wall thickness of the tube, and E ₀ represents the Young's modulus when the microvessel internal pressure is zero millimeters of mercury and mercury.

Continuing the above formula, the systolic blood pressure ( Psys ) of blood pressure has a quadratic curve function with the pulse wave transit time ( PTT ), and the correlation function is: Psys = a1 × PTT ² + a2 × PTT + a3, where , A1, a2, a3 represent the quadratic coefficient, first-order coefficient, and offset of the correlation function, respectively. Through this formula, the systolic pressure can be derived from the pulse wave transmission time.

Regarding the calculation method of the diastolic blood pressure ( Pdia ) of blood pressure, firstly, the pulse wave pressure ( PBP ) which is linearly related to the pulse wave transmission time ( PTT ) must be calculated. Among them, the pulse wave pressure ( PBP ) and the pulse wave transmission The correlation function of time ( PTT ) is: PBP = b1 × PTT + b2, where b1 and b2 respectively represent the coefficient and offset of the correlation function; in addition, pulse wave pressure ( PBP ) and systolic pressure ( Psys ), The relationship between diastolic blood pressure ( Pdia ) can be expressed by the following formula: PBP = Psys - Pdia . Obviously, after obtaining the pulse wave transmission time through the above formula, you can quickly fit in the model to get the blood pressure value (diastolic blood pressure). , Systolic blood pressure).

The system for measuring armless blood pressure through the electrode configuration of the present invention is composed of the above module structure, and simultaneously measures the information of the subject's electrocardiogram and blood flow pulses, providing a rapid estimation without the need of a blood pressure measurement armband Blood pressure measurement technology is a simple and efficient blood pressure measurement system.

A‧‧‧Subject

1‧‧‧ ECG detection module

2‧‧‧ wearable blood pressure measurement module

20‧‧‧body impedance sensing sub-module

22‧‧‧Pulse wave transit time operator module

201‧‧‧E electrode

202‧‧‧I electrode

FIG. 1 is a schematic diagram of a system for armless blood pressure measurement through an electrode configuration according to the present invention.

FIG. 2 is a first schematic diagram of a wearable blood pressure measurement module according to the present invention.

FIG. 3 is a second schematic diagram of a wearable blood pressure measurement module according to the present invention.

FIG. 4 is a schematic diagram of a method for comparing the time difference between the heartbeat and the pulse wave signals.

In the following, the present invention will be further described with examples and drawings. First, please refer to FIG. 1, which is a schematic diagram of a system for measuring armless blood pressure through an electrode configuration according to the present invention. Users of the system for blood pressure measurement, and the system of the present invention is worn as follows: Among them, the present invention has an electrocardiogram detection module 1, which can be implemented as a patch or a thin device when implemented, and is used to be placed near the receiver. The relative position of the chest surface of the subject A near the heart enables the electrocardiogram detection module 1 to better detect the heartbeat change of the subject A to generate an electrocardiogram signal data of the subject A.

In addition, the present invention has a wearable blood pressure measurement module 2 which can be implemented as a soft or hand-shaped device for wearing around a limb of the subject A. In this embodiment, The wearable blood pressure measurement module 2 is a hand-shaped ring device worn on the left wrist of the subject A, and it is used to receive the electrocardiographic signal signal data from the electrocardiogram detection module 1, and The pulse wave data of the subject A is detected through its own sub-module, and the blood pressure value of the subject A is calculated to implement the effect of the present invention.

The wearable blood pressure measurement module 2 of the present invention includes a plurality of sub-modules. Please refer to FIG. 2 and FIG. 3 together, which are the first and second of the wearable blood pressure measurement module of the present invention, respectively. schematic diagram.

Please refer to FIG. 2 first. The wearable blood pressure measurement module 2 of the present invention includes an integrated impedance sensing sub-module 20, and the body impedance sensing sub-module 20 has a plurality of sensing electrodes for The high-frequency constant current flows on the wrist of the subject A through the sensing electrode to measure the small change in the internal resistance signal of the subject A to generate integrated impedance signal data, and each of the sensing electrodes referred to, It is a set of I electrodes and a set of E electrodes, please refer to FIG. 3, in which it can be seen that the inner ring of the wearable blood pressure measurement module 2 is provided with an exposed set of I electrodes 202 and a set of E electrodes 201, The two sets of electrodes are arranged in opposite positions on opposite sides of the same circumferential surface surrounded by the wearing blood pressure measurement module 2. The two sets of electrodes are used to wear the subject A When the wearable blood pressure measurement module 2 is attached to the skin surface of the subject A to pass current, such an anti-symmetrical electrode arrangement on one circumferential surface is a better configuration for measuring pulse waves by current.

Please refer to FIG. 2 again, the wearable blood pressure measurement module 2 of the present invention further includes a pulse wave transit time operation sub-module 22 for receiving the body impedance sensing sub-module from the wearable blood pressure measurement module 2 In the body impedance signal data measured in group 20, the upper limb blood flow pulses of the subject and the ECG trace signal data from the ECG detection module 1 were obtained to describe the ECG trace signals of the subject A and the upper limb The blood flow pulse wave is used for waveform acquisition, and the waveforms are cross-referenced to estimate the time difference, which is the time of one pulse wave transmission of the subject A.

Finally, the wearable blood pressure measurement module 2 further estimates the systolic and diastolic blood pressure according to the pulse wave transmission time calculated by the pulse wave transmission time operation sub-module 22, so as to generate the test subject A's Blood pressure data.

Among them, regarding the pulse wave transmission time calculated by the pulse wave transmission time operation sub-module 22, the wearable blood pressure measurement module 2 uses the systolic pressure in blood pressure and the quadratic function of the pulse wave transmission time. Correlation, and the linear correlation between the pulse wave pressure of the blood flow and the pulse wave transmission time, including the difference between the pulse wave pressure and the systolic and diastolic blood pressure, is derived from the pulse wave transmission time. The systolic and diastolic blood pressure of the subject A was measured, and then the blood pressure was calculated.

Regarding the principle of how to compare the heartbeat and pulse signal waveforms of the subject, please refer to FIG. 4, which is a method applied by the present invention. By comparing the electrocardiogram signal (ECG) and the blood flow pulse wave (IPG) at the limb To find out the time difference of the pulse wave transmission time (PTT), and after finding out the pulse wave transmission time, you can quickly fit in the model to get the blood pressure value.

According to the system of the present invention for measuring armless blood pressure through an electrode configuration, according to the operation of the above modules, the subject can be relieved without experiencing the discomfort caused by the traditional compression of the limbs with an inflatable armband, but through the present invention A lightweight and simple measurement module that quickly measures blood pressure is an effective and simple blood pressure measurement system.

It should be understood that the above-mentioned embodiments are only used to explain the present invention and not intended to limit the present invention. Any modification, equivalent replacement, or improvement made within the meaning, spirit, and principle of the present invention, etc. It should be included in the protection scope of the present invention.

In summary, the present invention is technically innovative and has multiple effects that are inferior to the previous technology. It has fully met the novel and progressive statutory invention patent requirements. It has filed a patent application in accordance with the law and urges your office to approve this invention. The patent application encourages invention, and it is a matter of virtue.

Claims (5)

    A system for measuring armless blood pressure through an electrode configuration, comprising: an electrocardiogram detection module, which is arranged on an external subject's chest near the heart relative position to detect the generation of an electrocardiogram of the subject Describing signal data; A wearable blood pressure measurement module is worn around a limb of the external subject, and can receive the electrocardiographic drawing signal data from the electrocardiogram detection module, and the wearing Type blood pressure measurement module includes at least the following parts: an integrated impedance sensing sub-module including a plurality of sensing electrodes for passing a high-frequency constant current through each of the sensing electrodes into a limb of the external subject, An integrated impedance signal data is generated by measuring the slight change of the resistance signal; a pulse wave transmission time sub-module is used to obtain the external subject's heartbeat pulse wave from the electrocardiogram drawing signal data, and Obtain the limb blood flow pulse wave of the subject from the body impedance signal data; wherein, the pulse wave transmission time operation sub-module further performs waveforms on the external subject's heart beat pulse wave and limb blood flow pulse wave. Capture, The time difference of the cross-comparison waveform transmission is used to obtain a pulse wave transmission time of the external subject. Among them, the wearable blood pressure measurement module calculates systolic and diastolic blood pressure respectively according to the pulse wave transmission time. Finally, a blood pressure value data of the external subject is generated.         The system for measuring armless blood pressure through an electrode configuration as described in item 1 of the scope of the patent application, wherein each of the sensing electrodes in the body impedance sensing sub-module includes a set of I electrodes and a set of E electrodes Wherein, when the wearable blood pressure measurement module is arranged around the limb part of the external subject, the set of I electrodes and the set of E electrodes are respectively arranged in symmetrical positions in the wearable blood pressure measurement module. The surrounding inner side is on the same circumferential surface and contacts the outer subject's skin.         The system for blood pressure measurement without an armband as described in item 1 of the scope of the patent application, wherein the body impedance sensing sub-module amplifies, demodulates, and filters small changes in resistance signals to generate the body impedance Signal information.     The system for measuring blood pressure without an armband through an electrode configuration as described in item 1 of the scope of the patent application, wherein the blood pressure value data is calculated by the following formula according to the pulse wave transmission time: Among them, PTT is the value of the pulse wave transmission time, P is the value of the blood pressure value data, α represents the adjustment constant, L represents the distance of the pulse wave transmission, ρ represents the blood density, d represents the inner diameter of the microvessel, and w represents the wall of the tube Thickness, and E ₀ represents the Young's modulus when the microvessel internal pressure is zero millimeters of mercury and mercury.     The system for measuring armless blood pressure through an electrode configuration as described in item 1 of the scope of patent application, wherein the wearable blood pressure measurement module is based on the secondary pressure of the systolic blood pressure in the blood pressure and the pulse wave transmission time. The functional correlation, and the linear correlation between the pulse pressure of the blood flow and the transit time of the pulse wave, supplemented by the difference between the pulse pressure and the systolic and diastolic blood pressure, and then the external measured The blood pressure of the patient.