Real-time blood pressure and blood flow monitoring sensor and method thereof

Abstract

The invention provides a real-time blood pressure and blood flow monitoring sensor and a real-time blood pressure and blood flow monitoring method, which are used for continuously monitoring the same position of a blood vessel by combining a continuous wave technology and a pulse wave technology. The sensor comprises an array type transducer, a rectangular transducer, a flexible base body, a matching layer and a top protection layer, pulse waves are used for positioning blood vessels and measuring diameter changes to calculate blood pressure, and meanwhile the rectangular transducer monitors the blood flow velocity through the continuous wave Doppler technology. According to the technology, the limitation of a traditional monitoring method is overcome, wearable convenient monitoring is achieved, the accuracy and continuity of blood flow and blood pressure monitoring are improved, and important clinical application value is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical ultrasonic detection, and in particular to a real-time blood pressure and blood flow monitoring sensor and a method thereof. Background Art

[0002] With the continuous advancement of medical technology, accurate monitoring of blood flow and blood pressure plays an increasingly important role in clinical diagnosis and treatment. Traditional blood pressure monitoring methods mainly rely on cuff-type sphygmomanometers to obtain blood pressure data through indirect measurement. However, this method has obvious limitations, such as the inability to achieve continuous real-time monitoring and a significant impact on patient comfort. In addition, cuff-type sphygmomanometers are easily interfered by various factors during the measurement process, such as cuff tightness, changes in patient position, etc., which affect the accuracy of the measurement results.

[0003] On the other hand, blood flow monitoring is usually achieved through Doppler ultrasound technology, which can provide important information such as blood flow velocity, which is of great significance for evaluating vascular function and diagnosing vascular diseases. However, traditional Doppler ultrasound equipment is large in size and complex to operate. It requires specialized technicians to operate, cannot be carried around, and cannot achieve real-time monitoring. This limits its widespread application in clinical practice, especially in scenarios that require long-term, continuous monitoring of blood flow and blood pressure.

[0004] In recent years, the rapid development of ultrasound technology has provided new possibilities for the comprehensive monitoring of blood flow and blood pressure. Continuous wave Doppler and pulse wave are two commonly used ultrasound technologies, each with its own unique advantages. Continuous wave Doppler can provide high-precision blood flow velocity information, but it is difficult to locate the specific monitoring depth; while pulse wave can determine the depth and diameter changes of blood vessels, but its velocity measurement accuracy is relatively low. Therefore, combining these two technologies can achieve synchronous and continuous monitoring of blood flow and blood pressure, and improve the accuracy and reliability of monitoring.

[0005] Therefore, it is necessary to propose a new technical solution to improve the above technical problems. Summary of the invention

[0006] In view of the defects in the prior art, an object of the present invention is to provide a real-time blood pressure and blood flow monitoring sensor and method thereof.

[0007] A real-time blood pressure and blood flow monitoring sensor provided by the present invention includes an array transducer, a rectangular transducer, a flexible substrate, a matching layer and a top protective layer, wherein the array transducer and the rectangular transducer are both wrapped in the flexible substrate by pouring, and are used to continuously monitor the blood pressure and blood flow at the same position of the blood vessel; the matching layer is arranged below the flexible substrate; and the top protective layer is arranged above the flexible substrate.

[0008] Preferably, the array transducer comprises a 1×4 ultrasound array, which is installed perpendicular to the direction of the blood vessel and is used to generate and receive pulsed ultrasound waves to determine the position and diameter of the blood vessel.

[0009] Preferably, the rectangular transducer includes a rectangular transducer T1 and a rectangular transducer T2, the rectangular transducer T1 and the rectangular transducer T2 are placed at an angle θ, the rectangular transducer T2 is placed at an angle α to the skin surface, the angle α has a value range of 30° to 60°, the rectangular transducer T1 generates continuous ultrasonic waves, and the rectangular transducer T2 continuously receives ultrasonic echoes for monitoring blood flow velocity.

[0010] Preferably, the center frequencies of the array transducer and the rectangular transducer are f and f0 respectively, the spacing between the elements of the array transducer is set to be greater than one wavelength, and the spacing between the array transducer and the rectangular transducer is set to be greater than one wavelength.

[0011] Preferably, the pulse wave emitted by the array transducer has a time resolution of 50 Hz, the blood vessel position and diameter are calculated by the received echo signal, and the unit signal with the largest time difference between the upper and lower wall echo signals is selected as the blood vessel diameter signal.

[0012] Preferably, the position and size of the continuous wave Doppler sampling window are calculated and determined by the α and θ angles of the rectangular transducer and the distance from the array transducer, so as to receive and read the Doppler signal in the window, analyze and extract the Doppler frequency shift and calculate the blood flow velocity.

[0013] Preferably, it also includes a data processing unit for calculating the blood pressure based on the real-time change D(t) of the blood vessel diameter measured by the array transducer, and calculating the blood flow velocity based on the Doppler frequency shift Δf monitored by the rectangular transducer, and generating a monitoring report of the blood flow velocity and blood pressure.

[0014] Preferably, the flexible substrate, matching layer and top protective layer are made of silicone or PDMS materials to protect the transducer and fit the skin, and the width of the sensor is greater than or equal to 10 mm to cover the entire diameter of the measured blood vessel.

[0015] Preferably, the upper wall depth and the lower wall depth of the blood vessel are measured based on the array transducer, the vasodilation cross-sectional area and the vasoconstriction cross-sectional area are obtained, and then the real-time data value of the blood pressure is calculated; the rectangular transducer T1 and the rectangular transducer T2 in the rectangular transducer, the rectangular transducer T1 is responsible for emitting continuous waves with a center frequency of f0, and the rectangular transducer T2 is responsible for continuously receiving echoes with a center frequency of f1, thereby obtaining the Doppler frequency shift; the blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer.

[0016] The present invention also provides a real-time blood pressure and blood flow monitoring method, the method using the above-mentioned real-time blood pressure and blood flow monitoring sensor, the method comprising the following steps:

[0017] Step S1: According to the determined position of the monitored artery, the distance between the array transducer and the rectangular transducer is adjusted so that the focal position thereof is located at the position to be measured;

[0018] Step S2: The control circuit controls the array transducer to emit pulse waves with a time resolution of 50 Hz. The position and diameter of the blood vessel are calculated through the received echo signal to obtain blood pressure information. The signal of the unit with the largest difference between the upper and lower wall echo signals among all units of the array transducer is selected, and the change of the blood vessel diameter data under the unit is monitored in real time.

[0019] Step S3: The rectangular transducer transmits and receives continuous waves. After the position and diameter of the blood vessel are determined by the pulse wave, the position and size of the continuous wave Doppler sampling window are calculated by combining the α and θ angles of the rectangular transducer and the distance from the array transducer to optimize the reception and calculation of the Doppler frequency shift signal.

[0020] Step S4: Through the data processing unit, the blood pressure is calculated based on the real-time change D(t) of the blood vessel diameter measured by the array transducer, combined with the certain correlation between blood pressure and blood vessel diameter; the blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer; and the pulse wave and continuous wave Doppler data are comprehensively analyzed to generate a monitoring report of blood flow velocity and blood pressure, which is then wirelessly transmitted to the display device.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention can continuously and in real time monitor blood pressure and blood flow velocity through wearable patch sensor technology, providing more detailed and continuous data support for clinical diagnosis and treatment; the present invention combines the advantages of continuous wave Doppler and pulse wave ultrasound technologies; continuous wave Doppler can provide high-precision blood flow velocity information, while pulse wave can determine the depth and diameter changes of blood vessels; through the combination of these two technologies, not only the measurement accuracy of blood flow velocity is improved, but also the blood pressure value can be accurately calculated, thereby overcoming the shortcomings of traditional methods in monitoring accuracy;

[0023] 2. The wearable patch sensor of the present invention is thin, soft and can better fit the skin, reduce the patient's discomfort and improve the comfort during the monitoring process; the sensor of the present invention adopts a miniaturized design, with small size and light weight, which is easy to carry and wear, and realizes the monitoring of blood flow and blood pressure anytime and anywhere;

[0024] 3. The present invention can not only monitor blood pressure and blood flow velocity, but also generate detailed monitoring reports by comprehensively analyzing pulse wave and continuous wave Doppler data, providing more comprehensive data information for clinical diagnosis and treatment; this comprehensive monitoring capability helps doctors to more accurately assess the health status of patients and formulate more reasonable treatment plans;

[0025] 4. The present invention has broad application prospects in the medical field; it can play an important role in the diagnosis and treatment monitoring of cardiovascular diseases and the daily health management of patients with chronic diseases; in addition, with the development of telemedicine and smart medicine, the wearable monitoring sensor of the present invention can also be connected to smart devices such as smart phones and tablets to achieve remote monitoring and data sharing, providing strong support for the intelligence and convenience of medical services. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0027] Figure 1 This is a structural schematic diagram of a real-time blood flow and blood pressure monitoring sensor of the present invention;

[0028] Figure 2 This is an exploded view of the real-time blood flow and blood pressure monitoring sensor of the present invention;

[0029] Figure 3 This is a schematic diagram of the working principle of the real-time blood flow and blood pressure monitoring sensor of the present invention;

[0030] Figure 4 The figure is a schematic diagram of the working process of the real-time blood flow and blood pressure monitoring sensor of the present invention.

[0031] in:

[0032] Array transducer 1 Matching layer 4

[0033] Rectangular transducer 2 Top protective layer 5

[0034] Flexible substrate 3 DETAILED DESCRIPTION

[0035] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0036] Embodiment 1:

[0037] Reference Figure 1 and Figure 2 According to the present invention, a real-time blood pressure and blood flow monitoring sensor is provided, comprising an array transducer 1, a rectangular transducer 2, a flexible substrate 3, a matching layer 4 and a top protective layer 5, wherein the array transducer 1 and the rectangular transducer 2 are both wrapped in the flexible substrate 3 by pouring, and are used to continuously monitor the blood pressure and blood flow at the same position of the blood vessel; the matching layer 4 is arranged below the flexible substrate 3; and the top protective layer 5 is arranged above the flexible substrate 3.

[0038] The array transducer 1 includes a 1×4 ultrasonic array, which is installed perpendicular to the direction of the blood vessel and is used to generate and receive pulsed ultrasonic waves to determine the position and diameter of the blood vessel. The rectangular transducer 2 includes a rectangular transducer T1 and a rectangular transducer T2. The rectangular transducer T1 and the rectangular transducer T2 are placed at an angle of θ, and the rectangular transducer T2 is placed at an angle of α to the skin surface. The value range of the angle α is 30° to 60°. The rectangular transducer T1 generates continuous ultrasonic waves, and the rectangular transducer T2 continuously receives ultrasonic echoes for monitoring blood flow velocity. The center frequencies of the array transducer 1 and the rectangular transducer 2 are f and f0, respectively. The spacing between the elements of the array transducer is set to be greater than one wavelength, and the spacing between the array transducer and the rectangular transducer is set to be greater than one wavelength. The pulse wave time resolution emitted by the array transducer 1 is 50Hz. The position and diameter of the blood vessel are calculated by the received echo signal, and the unit signal with the largest time difference between the upper and lower wall echo signals is selected as the blood vessel diameter signal. The position and size of the continuous wave Doppler sampling window are calculated and determined by the angles α and θ of the rectangular transducer 2 and the distance from the array transducer 1, and are used to receive and read the Doppler signal in the window to analyze and extract the Doppler frequency shift and calculate the blood flow velocity. It also includes a data processing unit, which is used to infer the blood pressure based on the real-time change D(t) of the blood vessel diameter measured by the array transducer 1, and calculate the blood flow velocity based on the Doppler frequency shift Δf monitored by the rectangular transducer 2, and generate a monitoring report of the blood flow velocity and blood pressure. The flexible substrate 3, the matching layer 4 and the top protective layer 5 are made of silica gel and PDMS materials to protect the transducer and fit the skin, and the width of the sensor is greater than or equal to 10 mm to cover the entire diameter of the measured blood vessel. Based on the array transducer 1, the depth of the upper wall and the lower wall of the blood vessel are measured, the cross-sectional area of ​​the vasodilation and the cross-sectional area of ​​the blood vessel are obtained, and then the real-time data value of the blood pressure is calculated; the rectangular transducer T1 and the rectangular transducer T2 in the rectangular transducer 2, the rectangular transducer T1 is responsible for emitting continuous waves with a center frequency of f0, and the rectangular transducer T2 is responsible for continuously receiving echoes with a center frequency of f1 received, thereby obtaining the Doppler frequency shift; according to the Doppler frequency shift Δf monitored by the rectangular transducer 2, the blood flow velocity is calculated.

[0039] Reference Figure 3 and Figure 4The present invention also provides a real-time blood pressure and blood flow monitoring method, the method using the above-mentioned real-time blood pressure and blood flow monitoring sensor, the method comprising the following steps:

[0040] Step S1: according to the determined position of the monitored artery, the distance between the array transducer 1 and the rectangular transducer 2 is adjusted so that the focal position thereof is located at the position to be measured;

[0041] Step S2: The control circuit controls the array transducer 1 to emit pulse waves with a time resolution of 50 Hz, and calculates the position and diameter of the blood vessel through the received echo signal to obtain blood pressure information; the signal of the unit with the largest difference between the upper and lower wall echo signals among all the units of the array transducer 1 is selected, and the change of the blood vessel diameter data under the unit is monitored in real time;

[0042] Step S3: the rectangular transducer 2 transmits and receives continuous waves. After the position and diameter of the blood vessel are determined by the pulse wave, the position and size of the continuous wave Doppler sampling window are calculated in combination with the α and θ angles of the rectangular transducer 2 and the distance from the array transducer 1, so as to optimize the reception and calculation of the Doppler frequency shift signal.

[0043] Step S4: Through the data processing unit, the blood pressure is calculated based on the real-time change D(t) of the blood vessel diameter measured by the array transducer 1, combined with the certain correlation between blood pressure and blood vessel diameter; the blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer 2; and the pulse wave and continuous wave Doppler data are comprehensively analyzed to generate a monitoring report of blood flow velocity and blood pressure, which is then transmitted wirelessly to the display device.

[0044] Embodiment 2:

[0045] With the continuous development of wearable device technology, miniaturized and portable medical monitoring equipment has gradually become a research hotspot. Wearable patch sensor technology has shown great application potential in the field of medical monitoring due to its convenience and comfort. By combining wearable patch sensor technology with continuous wave and pulse wave technology, a new type of real-time blood pressure and blood flow monitoring sensor can be developed to achieve continuous monitoring of the same position of the blood vessel, providing more comprehensive data information for clinical diagnosis and treatment. The purpose of the present invention is to introduce wearable patch sensor technology, combined with continuous wave and pulse wave technology, to achieve continuous monitoring of blood flow and blood pressure at the same position of the blood vessel. By overcoming the limitations of traditional methods, improving the accuracy and reliability of monitoring, and providing more comprehensive and accurate data support for clinical diagnosis and treatment.

[0046] A real-time blood pressure and blood flow monitoring sensor, which combines continuous wave and pulse wave technology to continuously monitor the blood pressure and blood flow at the same position of the blood vessel. It includes an array transducer 1, a rectangular transducer 2, a flexible substrate 3, a matching layer 4, and a top protective layer 5. The array transducer 1 is a 1×4 or more ultrasonic array, which is installed perpendicular to the direction of the blood vessel and generates and receives pulse ultrasonic waves through a control circuit. The rectangular transducer 2 is composed of two pieces, T1 and T2, which are placed at an angle of θ between T1 and T2, and T2 is placed at an angle of α to the skin surface. To ensure the signal reception effect, the α angle value range is 30° to 60°, wherein T1 generates continuous ultrasonic waves through a control circuit, and T2 continuously receives ultrasonic echoes. The array transducer 1 and the rectangular transducer 2 are both wrapped in a flexible substrate 3 by pouring, and the flexible substrate 3, the matching layer 4 and the top protective layer 5 are made of materials such as silicone and PDMS, which can well protect the transducer and fit the skin. Blood pressure monitoring and blood flow monitoring are divided into two separate modules A and B. The distance between the array transducer 1 and the rectangular transducer 2 is adjusted to achieve blood vessel detection at different depths. Based on the measurement of the upper wall depth and the lower wall depth of the blood vessel by the array transducer 1, the vasodilation cross-sectional area and the vasoconstriction cross-sectional area are obtained, and then the real-time data value of the blood pressure is calculated. The two transducers T1 and T2 in the rectangular transducer 2, T1 is responsible for transmitting continuous waves with a center frequency of f0, and T2 is responsible for continuously receiving echoes with a center frequency of f1, thereby obtaining the Doppler frequency shift. The blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer 2.

[0047] In order to more accurately receive and distinguish pulse echoes from continuous wave echoes and avoid signal crosstalk, the center frequencies of array transducer 1 and rectangular transducer 2 are f and f0 respectively, and the spacing between the elements of array transducer 1 is set to be greater than one wavelength, and the spacing between array transducer 1 and rectangular transducer 2 is set to be greater than one wavelength. According to the approximate depth of the target blood vessel, the distance between array transducer 1 and rectangular transducer 2 is adjusted so that the focal position is located at the monitored blood vessel to be measured. Array transducer 1 transmits a pulse wave with a time resolution of at least 50Hz, and receives the echo signal, calculates the time difference between the blood vessel position and the echo signal, selects the signal of the unit with the largest time difference between the upper and lower wall echo signals of all units of array transducer 1 as the blood vessel diameter signal, and continuously reads the echo signal of the unit and converts it into a real-time blood pressure signal. After the position and diameter of the blood vessel are determined by the pulse wave, the position and size of the continuous wave Doppler sampling window are calculated and determined in combination with the α and θ angles of the rectangular transducer 2 and the distance from the array transducer 1, and the Doppler signal in the window is continuously received and read, and the Doppler frequency shift is analyzed and extracted to calculate the blood flow velocity. By using pulse waves for spatial resolution and position determination, combined with continuous wave Doppler technology and wearable patch sensors, the blood flow and blood pressure at the same position of the blood vessel can be comprehensively monitored to obtain the blood pressure and corresponding blood flow velocity of the blood vessel at that location.

[0048] The purpose of the present invention is to introduce wearable patch sensor technology to make monitoring equipment more convenient and comfortable. In addition, by combining continuous wave and pulse wave technology, continuous monitoring of blood flow and blood pressure at the same position of the blood vessel can be achieved, providing more comprehensive data information for clinical diagnosis and treatment.

[0049] A real-time blood pressure and blood flow monitoring sensor comprises an array transducer 1, a rectangular transducer 2, a flexible substrate 3, a matching layer 4 and a top protective layer 5.

[0050] The real-time blood flow and blood pressure monitoring sensor, its array transducer 1 and rectangular transducer 2 are both wrapped in a flexible matrix 3 by pouring, and the flexible matrix 3 is made of materials such as silicone and PDMS, which can protect the transducer and fit the skin well. The array transducer 1 is a 1×4 or more ultrasonic array, which is placed perpendicular to the blood vessel and generates and receives pulsed ultrasonic waves through a control circuit. The rectangular transducer 2 is T1 and T2, which are placed at an angle of θ between T1 and T2. The length direction of the rectangular transducer is parallel to the array transducer, and T2 is placed at an angle of α to the skin surface. To ensure the signal reception effect, the α angle value range is 30° to 60°, wherein T1 generates continuous ultrasonic waves through the control circuit, and T2 is responsible for continuously receiving ultrasonic echoes. The width of the real-time blood flow and blood pressure monitoring sensor is greater than or equal to 10 mm, covering the entire diameter of the measured blood vessel, ensuring that the information of the entire blood vessel can be detected even when there is a deviation in the installation.

[0051] In order to more accurately receive and distinguish pulse echoes from continuous wave echoes and avoid signal crosstalk, the center frequencies of the array transducer 1 and the rectangular transducer 2 are f and f0 respectively, the spacing between the elements of the array transducer 1 is set to be greater than one wavelength, and the spacing between the array transducer 1 and the rectangular transducer 2 is set to be greater than one wavelength.

[0052] The working principle of a real-time blood pressure and blood flow monitoring sensor is mainly divided into the following steps:

[0053] Step 1: The depth of the same artery in different human bodies usually has some general similarities, for example, in most people, the radial artery is located about 2 to 5 mm below the skin surface, the carotid artery is about 1 to 2 cm below the skin, and the femoral artery is about 2 to 3 cm deep in the groin area. According to the approximate location of the artery to be monitored, adjust the distance between the array transducer 1 and the rectangular transducer 2 so that their focal positions are located at the location to be measured.

[0054] Step 2: The control circuit controls the array transducer 1 to emit pulse waves with a time resolution of at least 50 Hz, and calculates the position and diameter of the blood vessel through the received echo signal, in order to accurately obtain blood pressure information. The signal of the unit with the largest difference between the upper and lower wall echo signals among all units of the array transducer 1 is selected, and the changes in the blood vessel diameter data under the unit are monitored in real time.

[0055] Step 3: The rectangular transducer 2 transmits and receives continuous waves. After determining the position and diameter of the blood vessel through the pulse wave, the position and size of the continuous wave Doppler sampling window are calculated based on the α and θ angles of the rectangular transducer 2 and the distance from the array transducer 1, and the reception and calculation of the Doppler frequency shift signal are optimized to ensure the accuracy of the blood flow velocity data.

[0056] Step 4: The data processing unit calculates the blood pressure based on the real-time change D(t) of the blood vessel diameter measured by the array transducer 1 and the certain correlation between blood pressure and blood vessel diameter. The blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer 2. The pulse wave and continuous wave Doppler data are comprehensively analyzed to generate a monitoring report of blood flow velocity and blood pressure, which is then wirelessly transmitted to the display device.

[0057] Based on the measurement of the upper wall depth and the lower wall depth of the blood vessel by the array transducer 1, the vasodilation cross-sectional area and the vasoconstriction cross-sectional area are obtained, and then the real-time data value of the blood pressure is calculated.

[0058] The two transducers T1 and T2 in the rectangular transducer 2, T1 is responsible for transmitting continuous waves with a center frequency of f0, and T2 is responsible for continuously receiving echoes with a center frequency of f1, thereby obtaining the Doppler frequency shift. The blood flow velocity is calculated based on the Doppler frequency shift Δf monitored by the rectangular transducer 2.

[0059] The present invention proposes a method combining continuous wave and pulse wave technology for comprehensive monitoring of the same blood vessel position. First, an array transducer is used to generate and receive pulse waves, and the depth of the blood vessel and the size and position of the sampling window are determined based on the time of flight TOF. At the same time, the echoes of the upper and lower walls in the sampling window are detected, and the changes in the blood vessel diameter are calculated to infer the blood pressure. On this basis, the α angle is adjusted so that the focal areas of the two rectangular transducers coincide with the pulse wave detection area, and the continuous wave Doppler technology is used to monitor the blood flow velocity at this position in real time. This method can not only improve the accuracy of blood flow and blood pressure monitoring, but also realize continuous monitoring of the same position of the blood vessel, providing more comprehensive data information for clinical diagnosis and treatment.

[0060] The present invention proposes a real-time blood pressure and blood flow monitoring sensor, which uses pulse waves for spatial resolution and position determination, combines continuous wave Doppler technology and wearable patch sensors, and realizes comprehensive monitoring of blood flow and blood pressure at the same position of a blood vessel. The following description is only an example and is not intended to limit the scope of the present invention and its application.

[0061] like Figure 1 , Figure 2As shown, a real-time blood pressure and blood flow monitoring sensor is composed of an array transducer 1, a rectangular transducer 2, a flexible substrate 3, a matching layer 4, a top protective layer 5 and the like. The array transducer 1 is a 1×4 or larger ultrasonic array, which is placed perpendicular to the direction of the blood vessel and generates and receives pulsed ultrasonic waves through a control circuit; the rectangular transducer 2 is composed of two pieces, T1 and T2, which are placed at an angle of θ between T1 and T2, and T2 is placed at an angle of α to the skin surface. To ensure the signal reception effect, the α angle value range is 30° to 60°. Among them, T1 generates continuous ultrasonic waves through the control circuit, and T2 is responsible for continuously receiving ultrasonic echoes. The array transducer 1 and the rectangular transducer 2 are both wrapped in the flexible substrate 3 by pouring. Due to the pouring method and to ensure the reception of ultrasonic signals, the α and θ angles of the rectangular transducer 2 are relatively fixed. In order to adapt to the monitoring of blood vessels at different depths, blood pressure monitoring and blood flow monitoring are divided into two separate modules A and B. The spacing between the array transducer 1 and the rectangular transducer 2 is adjusted to achieve blood vessel detection at different depths. The flexible substrate 3, matching layer 4 and top protective layer 5 are made of materials such as silicone and PDMS, which can well protect the transducer and fit the skin. To ensure easy installation, the real-time blood flow and blood pressure monitoring sensor is greater than or equal to 10mm wide, covering the entire diameter of the measured blood vessel, ensuring that the information of the entire blood vessel can be detected even if there is a deviation in the installation.

[0062] In order to more accurately receive and distinguish pulse echoes from continuous wave echoes and avoid signal crosstalk, the center frequencies of the array transducer 1 and the rectangular transducer 2 are f and f0 respectively, the spacing between the elements of the array transducer 1 is set to be greater than one wavelength, and the spacing between the array transducer 1 and the rectangular transducer 2 is set to be greater than one wavelength.

[0063] like Figure 3 , Figure 4 As shown, the working principle of a real-time blood pressure and blood flow monitoring sensor is mainly divided into the following steps:

[0064] Step 1: The depth of the same artery in different human bodies usually has some general similarities, for example, in most people, the radial artery is located about 2 to 5 mm below the skin surface, the carotid artery is about 1 to 2 cm below the skin, and the femoral artery is about 2 to 3 cm deep in the groin area. According to the approximate location of the artery to be monitored, adjust the distance between the array transducer 1 and the rectangular transducer 2 so that their focal positions are located at the location to be measured.

[0065] Step 2: The control circuit controls the array transducer 1 to emit pulsed waves with a time resolution of at least 50 Hz. Based on the received echo signals, calculate the position and diameter of the blood vessel to accurately obtain blood pressure information. Select the signal of the unit with the largest difference in echo signals between the upper and lower walls among all units of the array transducer 1, and continuously monitor the change in the blood vessel diameter data under this unit.

[0066] Step 3: The rectangular transducer 2 emits and receives continuous waves. After determining the position and diameter of the blood vessel through the pulsed wave, combine the α and θ angles of the rectangular transducer 2 and its distance from the array transducer 1 to calculate the position and size of the continuous wave Doppler sampling window, optimize the reception and calculation of the Doppler frequency shift signal, and ensure the accuracy of the blood flow velocity data.

[0067] Step 4: Through the data processing unit, based on the real-time change D(t) of the blood vessel diameter measured by the array transducer 1, and considering the certain correlation between blood pressure and blood vessel diameter, estimate the blood pressure. Calculate the blood flow velocity according to the Doppler frequency shift Δf monitored by the rectangular transducer 2. Then comprehensively analyze the data of the pulsed wave and continuous wave Doppler, generate a monitoring report of blood flow velocity and blood pressure, and transmit it wirelessly to the display device.

[0068] The relationship between the blood pressure and the blood vessel diameter can be calculated by the following formula:

[0069]

[0070] D(t) = 丨d down -d up 丨² In the formula, A(t) is the cross-sectional area of the blood vessel, D(t) is the blood vessel diameter, d up and d down are respectively the depth of the upper wall and the depth of the lower wall of the blood vessel measured by the array transducer.

[0071] The blood pressure information of the blood pressure detection module can be calculated by the following formula:

[0072]

[0073]

[0074] In the formula, P d is the diastolic blood pressure, A d is the cross-sectional area of the blood vessel during diastole, P s is the systolic blood pressure, A s is the cross-sectional area of the blood vessel during systole, and φ is the stiffness coefficient. Due to individual differences, the diastolic blood pressure P d and the systolic blood pressure P s are first measured by a mercury sphygmomanometer or an electronic blood pressure monitor, and then the cross-sectional area of the blood vessel during diastole A d and the cross-sectional area of the blood vessel during systole As , by matching the above data and substituting them into the formula, we can get the final real-time data of blood pressure:

[0075]

[0076] The continuous ultrasound Doppler calculation is as follows:

[0077] The two transducers in the rectangular transducer 2 are T1 and T2. T1 is responsible for transmitting continuous waves with a center frequency of f0, and T2 is responsible for continuously receiving echoes with a center frequency of f1. The Doppler shift is:

[0078] Δf=f1-f06

[0079] The blood flow rate can be calculated as:

[0080]

[0081] Therefore, this embodiment has the following advantages:

[0082] By using pulse waves for spatial resolution and position determination, combined with continuous wave Doppler technology and wearable patch sensors, comprehensive monitoring of blood flow and blood pressure at the same location of the blood vessel can be achieved, overcoming the limitations of traditional methods, and having important clinical application value and broad market prospects.

[0083] The present invention relates to a real-time blood pressure and blood flow monitoring sensor, which includes an array transducer, a rectangular transducer, a flexible substrate, a matching layer, a top protective layer and other components. Pulse waves are used for spatial resolution and position determination, and the upper wall depth and the lower wall depth of the blood vessel are measured based on the array transducer to obtain the vasodilation cross-sectional area and the vasoconstriction cross-sectional area, and then the real-time data value of the blood pressure is calculated. One of the two transducers in the rectangular transducer transmits a continuous wave, and the other continuously receives an echo, so as to obtain a Doppler frequency shift. The blood flow velocity is calculated based on the Doppler frequency shift monitored by the rectangular transducer. The present invention proposes a method combining continuous wave and pulse wave technology, which can realize comprehensive monitoring of blood flow and blood pressure at the same position of a blood vessel.

[0084] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0085] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0086] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A real-time blood pressure and blood flow monitoring sensor, characterized in that: The invention comprises an array transducer (1), a rectangular transducer (2), a flexible substrate (3), a matching layer (4) and a top protective layer (5), wherein the array transducer (1) and the rectangular transducer (2) are both wrapped in the flexible substrate (3) by pouring, and are used for continuously monitoring the blood pressure and blood flow at the same position of a blood vessel; the matching layer (4) is arranged below the flexible substrate (3); and the top protective layer (5) is arranged above the flexible substrate (3).

2. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The array transducer (1) comprises a 1×4 ultrasonic array, which is installed perpendicular to the direction of the blood vessel and is used to generate and receive pulsed ultrasonic waves to determine the position and diameter of the blood vessel.

3. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The rectangular transducer (2) comprises a rectangular transducer T1 and a rectangular transducer T2. The rectangular transducer T1 and the rectangular transducer T2 are placed at an angle θ, and the rectangular transducer T2 is placed at an angle α with respect to the skin surface. The angle α has a value interval of 30° to 60°. The rectangular transducer T1 generates continuous ultrasonic waves, and the rectangular transducer T2 continuously receives ultrasonic echoes for monitoring blood flow velocity.

4. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The center frequencies of the array transducer (1) and the rectangular transducer (2) are f and f0 respectively, and the spacing between the two is set to be greater than one wavelength.

5. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The pulse wave emitted by the array transducer (1) has a time resolution of 50 Hz. The blood vessel position and diameter are calculated using the received echo signals, and the unit signal with the largest time difference between the upper and lower wall echo signals is selected as the blood vessel diameter signal.

6. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The position and size of the continuous wave Doppler sampling window are calculated and determined by the α and θ angles of the rectangular transducer (2) and the distance to the array transducer (1), so as to receive and read the Doppler signal in the window, analyze and extract the Doppler frequency shift and calculate the blood flow velocity.

7. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: It also includes a data processing unit for calculating the blood pressure based on the real-time change D(t) of the blood vessel diameter measured by the array transducer (1), and calculating the blood flow velocity based on the Doppler frequency shift Δf monitored by the rectangular transducer (2), thereby generating a monitoring report of the blood flow velocity and the blood pressure.

8. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: The flexible substrate (3), matching layer (4) and top protective layer (5) are made of silica gel and PDMS materials to protect the transducer and fit the skin, and the width of the sensor is greater than or equal to 10 mm to cover the entire diameter of the blood vessel to be measured.

9. The real-time blood pressure and blood flow monitoring sensor according to claim 1, characterized in that: Based on the array transducer (1), the depth of the upper wall and the depth of the lower wall of the blood vessel are measured to obtain the cross-sectional area of ​​the vasodilation and the cross-sectional area of ​​the blood vessel, and then the real-time data value of the blood pressure is calculated; the rectangular transducer T1 and the rectangular transducer T2 in the rectangular transducer (2), the rectangular transducer T1 is responsible for transmitting continuous waves, the center frequency of which is f0, and the rectangular transducer T2 is responsible for continuously receiving echoes, the center frequency of the received echoes is f1, so as to obtain the Doppler frequency shift; according to the Doppler frequency shift Δf monitored by the rectangular transducer (2), the blood flow velocity is calculated.

10. A real-time blood pressure and blood flow monitoring method, characterized in that: The method uses the real-time blood pressure and blood flow monitoring sensor according to any one of claims 1 to 9, and the method comprises the following steps: Step S1: according to the determined position of the monitored arterial blood vessel, adjusting the distance between the array transducer (1) and the rectangular transducer (2) so that the focal position thereof is located at the position to be measured; Step S2: The control circuit controls the array transducer (1) to emit pulse waves with a time resolution of 50 Hz, and calculates the position and diameter of the blood vessel through the received echo signal to obtain blood pressure information; the signal of the unit with the largest difference between the upper and lower wall echo signals among all the units of the array transducer (1) is selected, and the change of the blood vessel diameter data under the unit is monitored in real time; Step S3: the rectangular transducer (2) transmits and receives a continuous wave, and after determining the position and diameter of the blood vessel through the pulse wave, the position and size of the continuous wave Doppler sampling window are calculated by combining the α and θ angles of the rectangular transducer (2) and the distance from the array transducer (1), thereby optimizing the reception and calculation of the Doppler frequency shift signal; Step S4: The data processing unit calculates the blood pressure based on the real-time change D(t) of the blood vessel diameter measured by the array transducer (1) and the certain correlation between blood pressure and blood vessel diameter; calculates the blood flow velocity based on the Doppler frequency shift Δf monitored by the rectangular transducer (2); and performs a comprehensive analysis on the pulse wave and continuous wave Doppler data to generate a monitoring report of the blood flow velocity and blood pressure, which is then wirelessly transmitted to a display device.

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