Method and system for testing diastolic pressure based on artery occlusion dynamic tracking

Abstract

The invention discloses a diastolic pressure testing method and system based on artery occlusion dynamic tracking, and belongs to the technical field of blood pressure testing. The method comprises the following steps: an initial state detection stage: detecting the state of an artery blood vessel without external force through a photoelectric detector to obtain a PPG oscillogram; in the pressure applying stage, air bag pressure larger than systolic pressure is applied to the tail of the measured target, and arterial blood flow is blocked; in the pressure grading monitoring stage, the pressure of the air bag is gradually released, and the pressure value and a PPG signal are monitored in real time; in the systolic pressure judgment stage, when the pressure of the air bag is reduced to a systolic pressure critical value, artery blood flow is instantly burst open and blocked, a pulse wave signal appears in a PPG waveform for the first time, and an instantaneous pressure value is recorded to obtain systolic pressure; in the diastolic pressure judgment stage, the critical point when the pressure of the air bag is transited from periodic blocking to complete opening is recognized, and the instantaneous pressure value is recorded to obtain the diastolic pressure. According to the method, the diastolic pressure and the systolic pressure can be accurately identified through artery occlusion dynamic tracking and the characteristic difference of the PPG waveform when the blood vessel state changes.

Description

Technical Field

[0001] The present invention relates to the technical field of blood pressure measurement, and particularly to a diastolic blood pressure measurement method and system based on arterial occlusion dynamic tracking. Background Art

[0002] In the field of blood pressure research, rats and mice have many significant advantages as experimental subjects and are thus widely used in various studies. Non-invasive blood pressure measurement technology (NIBP) is often used to measure their blood pressure. At present, there is a consensus on the detection of systolic blood pressure (SBP) in animals (such as rats and mice): by applying an airbag to block arterial blood flow at the tail, gradually releasing the pressure, and using piezoelectric, optoelectronic, or volumetric methods to detect the first pulse wave as the systolic blood pressure value. However, there is no unified standard for the measurement of diastolic blood pressure (DBP). In existing solutions, diastolic blood pressure is mostly determined by estimation or by selecting specific characteristic points (such as the inflection point or peak of the pulse wave) on the pulse wave, but these methods lack a scientific explanation based on the vascular physical model and indeed have the phenomenon of insufficient accuracy of measurement results in application. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a diastolic blood pressure measurement method and system based on arterial occlusion dynamic tracking.

[0004] The purpose of the present invention is achieved through the following technical solutions: In the first aspect of the present invention, there is provided: A diastolic blood pressure measurement method based on arterial occlusion dynamic tracking, including the following steps: In the initial state detection stage, the state of the arterial blood vessel without external force is detected by an optoelectronic detector to obtain a PPG waveform diagram; In the pressure application stage, an airbag pressure greater than the systolic blood pressure is applied to the tail of the target to be measured to block arterial blood flow; In the pressure grading monitoring stage, the airbag pressure is gradually released, and the pressure value and PPG signal are monitored in real time; In the systolic blood pressure determination stage, when the airbag pressure drops to the systolic blood pressure critical value, the arterial blood flow instantaneously breaks through the block, and the PPG waveform first appears a pulse wave signal. Record the instantaneous pressure value to obtain the systolic blood pressure; In the diastolic blood pressure determination stage, continuously reduce the airbag pressure. By analyzing the continuous change of the PPG signal, identify the critical point when the airbag pressure transitions from periodic occlusion to complete opening, and record the instantaneous pressure value to obtain the diastolic blood pressure.

[0005] Preferably, the diastolic blood pressure determination stage further includes the following steps: After the PPG waveform first appears a pulse wave signal, continuously reduce the airbag pressure. At this time, the airbag pressure is between the systolic blood pressure and the diastolic blood pressure. The pulse signal of the systolic blood pressure will appear in each pulse cycle, and it will be blocked again at the end of diastole; Continue to deflate the airbag until the airbag pressure drops to the diastolic blood pressure critical point. At this time, the arterial blood vessels are no longer blocked during the pulse cycle, and the PPG waveform shows complete fluctuation characteristics. The waveform at the end of diastole shows a continuous downward trend until the next systolic phase begins.

[0006] Preferably, when the airbag pressure is greater than the systolic blood pressure, there is no PPG signal; when the airbag pressure is less than the systolic blood pressure and greater than the diastolic blood pressure, the PPG signal appears intermittently, and the pulse wave signal only appears instantaneously at high pressure; when the airbag pressure is less than the diastolic blood pressure, the PPG signal is continuous and stable.

[0007] The second aspect of the present invention provides: A diastolic blood pressure testing system based on arterial occlusion dynamic tracking for implementing any of the above-mentioned diastolic blood pressure testing methods based on arterial occlusion dynamic tracking, including: An initial state detection module for detecting the state of the arterial blood vessels without external force through a photoelectric detector to obtain a PPG waveform diagram; A pressure application module for applying an airbag pressure greater than the systolic blood pressure to the tail of the target to be measured to block the arterial blood flow; A pressure grading monitoring module for gradually releasing the airbag pressure and real-time monitoring of the pressure value and the PPG signal; A systolic blood pressure determination module for when the airbag pressure drops to the systolic blood pressure critical value, the arterial blood flow instantaneously breaks through the block, and the pulse wave signal first appears in the PPG waveform, recording the instantaneous pressure value to obtain the systolic blood pressure; A diastolic blood pressure determination module for continuously reducing the airbag pressure, and by analyzing the continuous change of the PPG signal, identifying the critical point when the airbag pressure transitions from periodic occlusion to complete opening, and recording the instantaneous pressure value to obtain the diastolic blood pressure.

[0008] The beneficial effects of the present invention are: 1) Through arterial occlusion dynamic tracking and the characteristic differences of the PPG waveform when the vascular state changes, it is possible to accurately identify the critical points corresponding to diastolic blood pressure and systolic blood pressure.

[0009] 2) It can perform non-invasive blood pressure measurement. Description of the Drawings

[0010] Figure 1 It is a schematic diagram of blood vessels and PPG signals in the initial state; Figure 2 It is a schematic diagram of blood vessels and PPG signals in the blocked state; Figure 3 It is a schematic diagram of blood vessels and PPG signals at the moment when systolic blood pressure appears; Figure 4 It is a schematic diagram of blood vessels and PPG signals in the state where diastolic blood pressure does not appear; Figure 5 It is a schematic diagram of blood vessels and PPG signals at the moment when diastolic blood pressure appears; Figure 6 Schematic diagram of the change of PPG signal during the complete measurement process. Specific implementation manner

[0011] The following will combine the embodiments to clearly and completely describe the technical solutions of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0012] Refer to Figures 1-6 , the first aspect of the present invention provides: A diastolic blood pressure measurement method based on arterial occlusion dynamic tracking, including the following steps: Initial state detection stage, detecting the state of the artery without external force through a photoelectric detector to obtain a PPG waveform diagram; Pressure application stage, applying an airbag pressure greater than the systolic blood pressure to the tail of the measured target to block the arterial blood flow; Pressure grading monitoring stage, gradually releasing the airbag pressure and real-time monitoring the pressure value and PPG signal; Systolic blood pressure determination stage, when the airbag pressure drops to the systolic blood pressure critical value, the arterial blood flow instantaneously breaks through the block, and the pulse wave signal first appears in the PPG waveform. Record the instantaneous pressure value to obtain the systolic blood pressure; Diastolic blood pressure determination stage, continuously reducing the airbag pressure, by analyzing the continuous change of the PPG signal, identifying the critical point when the airbag pressure transitions from periodic occlusion to complete opening, and recording the instantaneous pressure value to obtain the diastolic blood pressure.

[0013] In this embodiment, the core idea is that under the condition of applying external airbag pressure, the volume change of the artery is affected by the combined action of internal blood pressure and external airbag pressure. By changing the airbag pressure, the blood vessel volume can be affected. Therefore, when the airbag pressure is equivalent to the pressure at some special blood pressure points such as systolic blood pressure and diastolic blood pressure, the blood vessel volume will mutate, and these mutations can be reflected from the photoplethysmogram (PPG). Therefore, by identifying the pressure of the external airbag at the moment of PPG waveform mutation, the systolic blood pressure or diastolic blood pressure can be obtained.

[0014] In the stage where the airbag pressure is greater than the diastolic blood pressure, in each pulse cycle, the blood vessel has a moment when it completely collapses and the blood flow is blocked. Until the airbag pressure is equal to or lower than the diastolic blood pressure, there is no longer a moment when the blood vessel completely collapses. This change is reflected in the photoelectric blood volume image. Therefore, by analyzing the airbag pressure corresponding to the moment when the slope change of the blood volume graph at the end of diastole is the largest, the diastolic blood pressure can be obtained.

[0015] In some embodiments, the diastolic blood pressure determination stage further includes the following steps: After the PPG waveform first appears the pulse wave signal, continuously reduce the airbag pressure. At this time, the airbag pressure is between the systolic pressure and the diastolic pressure. The pulse signal of the systolic pressure will appear in each pulse cycle, and it will be blocked again at the end of diastole; Continue to deflate until the airbag pressure drops to the diastolic critical point. The arterial blood vessels are no longer blocked during the pulse cycle. The PPG waveform presents complete fluctuation characteristics. The waveform at the end of diastole shows a continuous downward trend until it enters the next systolic phase.

[0016] In this embodiment, when the airbag pressure is between the systolic pressure and the diastolic pressure, the pulse signal of the systolic pressure will appear in each pulse cycle, and it will be blocked again at the end of diastole. On the PPG waveform image, the end of diastole tends to be flat, and the slope is close to zero (see Figure 4 ). Continue to deflate until the airbag pressure drops to the diastolic critical point. The arterial blood vessels are no longer blocked during the pulse cycle. The PPG waveform presents complete fluctuation characteristics. The waveform at the end of diastole shows a continuous downward trend until it enters the next systolic phase. Therefore, the slope of the current pulse at the end of diastole is higher than the slope of the end of diastole of the pulse at other times (Appendix Figure 5 ).

[0017] In some embodiments, when the airbag pressure is greater than the systolic pressure, there is no PPG signal; when the airbag pressure is less than the systolic pressure and greater than the diastolic pressure, the PPG signal appears intermittently, and the pulse wave signal only appears instantaneously at high pressure; when the airbag pressure is less than the diastolic pressure, the PPG signal is continuous and stable.

[0018] The second aspect of the present invention provides: A diastolic blood pressure test system based on arterial occlusion dynamic tracking, which is used to implement any of the above-mentioned diastolic blood pressure test methods based on arterial occlusion dynamic tracking, including: An initial state detection module, which is used to detect the state of the arterial blood vessel without external force through a photoelectric detector to obtain a PPG waveform diagram; A pressure application module, which is used to apply an airbag pressure greater than the systolic pressure to the tail of the measured target to block the arterial blood flow; A pressure grading monitoring module, which is used to gradually release the airbag pressure and monitor the pressure value and PPG signal in real time; A systolic pressure determination module, which is used to record the instantaneous pressure value as the systolic pressure when the arterial blood flow instantaneously breaks through the blockage and the PPG waveform first appears the pulse wave signal when the airbag pressure drops to the systolic pressure critical value; A diastolic pressure determination module, which is used to continuously reduce the airbag pressure, and by analyzing the continuous change of the PPG signal, identify the critical point when the airbag pressure transitions from periodic blockage to full opening, and record the instantaneous pressure value as the diastolic pressure.

[0019] The above are only the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the concept described herein through the above teachings or the techniques or knowledge in related fields. Any changes and variations made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A diastolic blood pressure test method based on dynamic tracking of arterial occlusion, characterized in that: The following steps are involved: In the initial state detection stage, the PPG waveform is obtained by detecting the state of the arterial blood vessels without external force through the photoelectric detector; During the pressure application phase, a balloon pressure greater than the systolic pressure is applied to the tail of the target to block the arterial blood flow; During the pressure graded monitoring stage, the airbag pressure is gradually released, and the pressure value and PPG signal are monitored in real time; In the systolic pressure determination stage, when the balloon pressure drops to the critical value of systolic pressure, the arterial blood flow is instantly unblocked, and the pulse wave signal appears for the first time on the PPG waveform. The instantaneous pressure value is recorded to obtain the systolic pressure. During the diastolic pressure determination stage, the balloon pressure is continuously reduced, and the critical point when the balloon pressure transitions from periodic blocking to full opening is identified by analyzing the continuous changes in the PPG signal. The instantaneous pressure value is recorded to obtain the diastolic pressure.

2. The diastolic pressure testing method based on dynamic tracking of arterial occlusion according to claim 1, characterized in that: The diastolic pressure determination stage further comprises the following steps: After the pulse wave signal appears for the first time in the PPG waveform, the airbag pressure is continuously reduced. At this time, the airbag pressure is between the systolic pressure and the diastolic pressure. The systolic pressure pulse signal will appear in each pulse cycle, and will be blocked again at the end of diastole. When the balloon pressure continues to be deflated to drop to the diastolic pressure zero boundary point, the arterial blood vessels are no longer blocked during the pulse cycle, the PPG waveform shows complete fluctuation characteristics, and the end-diastolic waveform shows a continuous downward trend until entering the next contraction period.

3. The diastolic pressure testing method based on dynamic tracking of arterial occlusion according to claim 1, characterized in that: When the balloon pressure is greater than the systolic pressure, there is no PPG signal; when the balloon pressure is less than the systolic pressure and greater than the diastolic pressure, the PPG signal appears intermittently and the pulse wave signal only appears at the moment of high pressure; when the balloon pressure is less than the diastolic pressure, the PPG signal is continuous and stable.

4. A diastolic pressure test system based on dynamic tracking of arterial occlusion, characterized in that: The method for testing diastolic pressure based on dynamic tracking of arterial occlusion according to any one of claims 1 to 3 comprises: An initial state detection module, used to detect the state of the arterial blood vessels not subjected to external force by means of a photoelectric detector to obtain a PPG waveform diagram; A pressure application module is used to apply a balloon pressure greater than the systolic pressure to the tail of the target to block arterial blood flow; The pressure grading monitoring module is used to gradually release the airbag pressure and monitor the pressure value and PPG signal in real time; The systolic pressure determination module is used to record the instantaneous pressure value to obtain the systolic pressure when the airbag pressure drops to the critical value of the systolic pressure, the arterial blood flow is instantly unblocked, the pulse wave signal appears for the first time in the PPG waveform, and the systolic pressure is obtained; The diastolic pressure determination module is used to continuously reduce the airbag pressure. By analyzing the continuous changes in the PPG signal, it identifies the critical point when the airbag pressure transitions from periodic blocking to full opening, and records the instantaneous pressure value to obtain the diastolic pressure.

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