System, method and puncture needle for measuring blood pressure

Abstract

The invention provides a system and method for measuring blood pressure and a puncture needle. The system comprises the puncture needle, an optical fiber sensor, an optical fiber transmission line and a photoelectric conversion regulator. The puncture needle comprises a puncture needle body and a puncture needle core; the body comprises a sheathing canal and a base; the front end of the base is connected with the rear end of the sheath; an infusion interface and a blood pressure measurement interface are arranged at the rear end of the base; the needle core is used for guiding the sheathing canal to puncture into a blood vessel; the sheathing canal is used for introducing blood into an inner cavity of the base; the optical fiber sensor comprises a sensor body, a medical instrument interface and an optical fiber interface; the optical fiber sensor is connected with the blood pressure measuring interface through the medical instrument interface and is indirectly connected with the photoelectric conversion regulator through the optical fiber interface; when the medical instrument interface and the blood pressure measurement interface are in a connected state, the pressure sensitive end of the sensor body enters the inner cavity of the puncture base; the photoelectric conversion regulator is used for emitting laser to the optical fiber sensor and calculating blood pressure information according to optical information reflected by the optical fiber sensor. The electronic sphygmomanometer can measure blood pressure more accurately.

Description

Technical Field

[0001] The present application belongs to the field of medical device technology, and in particular, relates to a system, method and puncture needle for measuring blood pressure. Background Art

[0002] Blood pressure is the most basic vital sign. It reflects the capacity, load and work of the heart and is an important indicator for measuring circulatory function. Accurate and rapid blood pressure monitoring is particularly important for the diagnosis and treatment of critically ill patients. Among them, invasive arterial blood pressure monitoring has become the gold standard for arterial blood pressure monitoring because of its ability to continuously and real-time monitor hemodynamic changes, and is widely used in the monitoring of critically ill patients.

[0003] The invasive arterial blood pressure monitoring system currently used in clinical practice is based on Pascal's law and the principle of liquid equal pressure transmission. A catheter filled with heparin saline is placed inside the artery. The pressure inside the catheter is measured by a resistive pressure transducer at the rear end of the catheter to replace the arterial blood pressure, rather than directly measuring the arterial blood pressure. The length, material and elasticity of the pressure gauge tube can affect the measurement results. Studies have shown that for every 80cm increase in the length of the pressure gauge tube, the systolic pressure will increase by 10mmHg, and the material of the pipe will affect the compliance of the pressure gauge tube. The difference in compliance will reduce the accuracy of the measurement results. In addition, the piezoelectric sensor is affected by the pressurization system, the hydrostatic pressure of the liquid surface and the elastic system of the catheter wall in the liquid catheter. The system must be zeroed before measurement, which greatly affects the accuracy and stability of the monitoring results. In addition, more and more critically ill patients need to be examined and operated under MRI, CT or digital subtraction technology. The existing resistive sensors cannot work accurately or even damage the sensors in strong magnetic fields, strong radiation and high energy environments.

[0004] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present application is to provide a system, method and puncture needle for measuring blood pressure, aiming to solve the deficiencies or defects pointed out in the background technology.

[0006] In a first aspect, the present application provides a blood pressure measurement system, the system comprising a puncture needle, a Fabry-Perot cavity optical fiber sensor, an optical fiber transmission line, and a photoelectric conversion regulator; The puncture needle includes a puncture needle body and a puncture needle core, both of which are hollow structures; the puncture needle body is made of non-metallic material; The puncture needle body includes a puncture needle sheath and a puncture base; The front end of the puncture base is connected to the rear end of the puncture needle sheath; the rear end of the puncture base is provided with an infusion interface for connecting to an infusion tube and a blood pressure measurement interface for connecting to a Fabry-Perot cavity optical fiber sensor; The front end of the puncture needle core is a short bevel angle structure; the puncture needle core is used to guide the puncture needle sheath tube to puncture into a blood vessel, which is an artery or a vein; the puncture needle sheath tube is used to introduce the blood in the blood vessel into the inner cavity of the puncture needle base; The Fabry-Perot cavity optical fiber sensor comprises a sensor body, a medical device interface and an optical fiber interface matching the blood pressure measurement interface of the puncture needle; The Fabry cavity optical fiber sensor is connected to the blood pressure measurement interface of the puncture needle through the medical device interface, and is connected to one end of the optical fiber transmission line through the optical fiber interface, and the other end of the optical fiber transmission line is connected to the photoelectric conversion regulator; when the medical device interface and the blood pressure measurement interface are in a connected state, the pressure sensitive end of the sensor body enters the inner cavity of the puncture base; The photoelectric conversion regulator is used to emit laser to the Fabry-Perot cavity optical fiber sensor and calculate blood pressure information based on the optical information reflected by the Fabry-Perot cavity optical fiber sensor.

[0007] In some embodiments, the medical device port of the Fabry-Perot cavity fiber optic sensor is a Luer outer cone interface.

[0008] In some embodiments, the periphery of the sensor body is wrapped with a skin.

[0009] In some embodiments, a skin covering the front end of the sensor body is provided with a screw cap.

[0010] In the second aspect, the present application provides a puncture needle, which includes a puncture needle body and a puncture needle core, both of which are hollow structures; the material of the puncture needle body is non-metallic material; the puncture needle body includes a puncture needle sheath and a puncture base; the front end of the puncture base is connected to the rear end of the puncture needle sheath; the rear end of the puncture base is provided with an infusion interface for connecting an infusion tube and a blood pressure measurement interface for connecting a Fabry-Perot cavity optical fiber sensor; the front end of the puncture needle core is a short bevel angle structure; the puncture needle core is used to guide the puncture needle sheath to puncture into a blood vessel, which is an artery or a vein; the puncture needle sheath is used to introduce blood in the blood vessel into the inner cavity of the puncture needle base.

[0011] In some embodiments, the blood pressure measurement interface and the infusion interface are both Luer cone interfaces.

[0012] In some embodiments, the outer circumference of the blood pressure measurement interface is provided with threads.

[0013] In some embodiments, a blood storage tank for determining the puncture blood return status is provided at the rear end of the puncture needle core.

[0014] In some embodiments, when the puncture needle is in a standby state, the puncture needle core passes through the puncture base and the puncture needle sheath through the infusion interface, so that the blood storage tank of the puncture needle core and the infusion interface form a sealing structure.

[0015] In some embodiments, the puncture needle further comprises a protective cap for sealing the blood pressure measurement interface.

[0016] In a third aspect, the present application provides a blood pressure measurement method, which is implemented based on the blood pressure measurement system provided by any of the above embodiments; the method comprises: The puncture needle core guides the puncture needle sheath to puncture into the target blood vessel, so that the blood in the target blood vessel flows into the inner cavity of the puncture base through the puncture needle sheath and directly contacts the pressure sensitive end of the sensor body in the Fabry-Perot cavity optical fiber sensor; the target blood vessel is an artery or a vein; Laser is emitted to the Fabry-Perot cavity optical fiber sensor through a photoelectric conversion regulator, and blood pressure information is calculated based on optical information reflected by the Fabry-Perot cavity optical fiber sensor.

[0017] In some embodiments, after the puncture needle sheath is inserted into the target blood vessel, the method further comprises: Based on the blood reservoir of the puncture needle core, determine whether the blood return status after puncture is normal; If the blood return state is normal, the puncture needle core is pulled out of the puncture needle body by pushing the puncture base, and the puncture needle sheath is left in the target blood vessel.

[0018] In some embodiments, when the target blood vessel is a vein and the infusion interface of the puncture needle is connected to an infusion device, before the photoelectric conversion regulator emits laser light to the Fabry-Perot cavity optical fiber sensor, the method further includes: Close the infusion regulating valve or three-way valve to suspend fluid infusion.

[0019] In some embodiments, when the target blood vessel is an artery and the infusion interface of the puncture needle is connected to a pressurized flushing device, the method further includes: The arterial line is flushed regularly or irregularly using a pressurized flushing device.

[0020] In some embodiments, before emitting laser to the Fabry-Perot cavity optical fiber sensor through the photoelectric conversion regulator, the method further includes: setting a zero point according to the patient's body position.

[0021] The blood pressure measurement system provided by the present application uses a Fabry-Perot cavity optical fiber sensor for blood pressure measurement. The Fabry-Perot cavity optical fiber sensor is a sensor that uses the Fabry-Perot cavity interference principle to measure pressure. It has the characteristics of small size, high precision, and fast response. More importantly, it also has the characteristics of anti-electromagnetic interference, so it can be competent for blood pressure monitoring tasks in special environments, such as functional MRI examinations during cranial and brain tumor surgery, MRI examinations for critically ill patients, and cardiac interventional surgery for heart patients. Its working principle is to determine the change of external pressure by measuring the change of optical path difference in the Fabry-Perot cavity. The Fabry-Perot cavity is specifically composed of two parallel reflecting surfaces, one of which is fixed in position, and the other reflecting film is used as a pressure-sensitive diaphragm, which can be deformed under the action of external pressure, thereby changing the length of the Fabry-Perot cavity. The present application places the blood pressure measurement interface of a special puncture needle in the inner cavity of the puncture needle (specifically, the inner cavity of the puncture base of the puncture needle). After the puncture needle punctures the target blood vessel, the blood in the target blood vessel will be led into the inner cavity of the puncture needle, so that the blood will directly contact the Fabry-Perot cavity fiber optic sensor in the inner cavity of the puncture needle. Then, the blood can produce a squeezing effect on the Fabry-Perot cavity in the Fabry-Perot cavity fiber optic sensor, causing its length to change. Then, the photoelectric conversion regulator can calculate the blood pressure through the optical information reflected by the Fabry-Perot cavity fiber optic sensor.

[0022] The puncture needle of the present application is provided with a blood pressure measuring interface, and the Fabry-Perot cavity optical fiber sensor can be integrated with the puncture needle by docking with the blood pressure measuring interface, and enter the inner cavity of the puncture needle to directly contact the blood in the target blood vessel. Compared with the method of measuring the pressure in the catheter to replace the arterial blood pressure in the related technology, the blood pressure measurement accuracy can be significantly improved. At this time, the blood pressure measurement accuracy is equivalent to the accuracy of blood pressure measurement by directly implanting the Fabry-Perot cavity optical fiber sensor into the target blood vessel. Since the present application does not require the Fabry-Perot cavity optical fiber sensor to be implanted into the target blood vessel, the present application not only improves the blood pressure measurement accuracy, but also simplifies the placement and recovery operations of the sensor during blood pressure measurement, and also reduces the infection risks that may be caused by these operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of the composition of a blood pressure measurement system provided in an embodiment of the present application; Figure 2 is a schematic diagram of the puncture needle core provided in an embodiment of the present application being inserted into the puncture needle body; Figure 3 is a schematic diagram of the connection of various components in a blood pressure measurement system when measuring blood pressure provided in an embodiment of the present application; Figure 4 is a cross-sectional view of a partial structure of a sensor body of a Fabry-Perot cavity optical fiber sensor provided in an embodiment of the present application; Figure 5 Schematic diagram of the structure of the Fabry-Perot cavity optical fiber sensor provided in the embodiment of the present application; Figure 6 is a flow chart of a blood pressure measurement method provided in an embodiment of the present application; Figure 7 It is a schematic diagram of connecting a pressurized flushing device through an infusion interface when measuring blood pressure provided in an embodiment of the present application.

[0024] The reference numerals are as follows: Blood pressure measurement system 00; puncture needle 1; Fabry-Perot cavity optical fiber sensor 2; optical fiber transmission line 3; photoelectric conversion regulator 4; puncture needle body 11; puncture needle core 12; puncture needle sheath 111; puncture base 112; infusion interface 1121; blood pressure measurement interface 1122; inner cavity 1123 of puncture needle base; blood reservoir 121; sensor body 21; optical fiber interface 22; two-stage sleeve 211; high-reflection film 212; Fabry-Perot cavity 213; single-mode optical fiber 214 in the sensor body; fiber core 2141; cladding 2142; coating layer 2143; protective layer 2144; sensitive diaphragm 215; screw cap 216 provided on the front end skin of the sensor body. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and beneficial effects of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0026] In order to illustrate the technical solution described in this application, a specific embodiment is provided below for illustration.

[0027] The first aspect of the present application provides a blood pressure measurement system. In some embodiments, Figure 1 As shown, the blood pressure measurement system 00 includes a puncture needle 1, a Fabry-Perot cavity optical fiber sensor 2, an optical fiber transmission line 3 and a photoelectric conversion regulator 4, which are respectively introduced below: (1) The puncture needle 1 includes a puncture needle body 11 and a puncture needle core 12 .

[0028] The puncture needle body 11 and the puncture needle core 12 are both hollow structures so as to introduce and contain blood in the blood vessel.

[0029] Regarding the puncture needle body 11, Figure 1 As shown, it includes a puncture needle sheath 111 and a puncture base 112. The front end of the puncture base 112 is connected to the rear end of the puncture needle sheath 111; the rear end of the puncture base 112 is provided with two interfaces, namely, an infusion interface 1121 for connecting an infusion tube and a blood pressure measurement interface 1122 for connecting a Fabry-Perot cavity optical fiber sensor. The rear end of the puncture base 112 can be any side of the puncture base 112, and the front end can be a side opposite to the rear end.

[0030] Specifically, the puncture needle sheath 111 is a hollow structure, which is used to introduce the blood in the blood vessel into the inner cavity of the puncture base 112 after puncturing into the blood vessel. In some embodiments, the puncture needle sheath 111 can be a catheter-like structure. The puncture base 112 is also a hollow structure, and there is a chamber (i.e., the inner cavity 1123) inside it. The puncture base 112 has three channels connected to the inner cavity 1123. This embodiment does not specifically limit the shape of the channel. These three channels are respectively used to connect the puncture needle sheath 111, the infusion interface 1121 for connecting the infusion tube, and the blood pressure measurement interface 1122 for connecting the Fabry-Perot cavity optical fiber sensor. Further, the puncture needle sheath 111 and the puncture base 112 can be an integrally formed structure. The puncture needle sheath 111 and the puncture base 112 can also be two independently made, but fixedly connected to form an integral structure. The implementation method of the fixed connection is not particularly limited in this embodiment.

[0031] Regarding the puncture needle core 12, it is used to guide the puncture needle sheath 111 to puncture into a blood vessel, so that the puncture needle sheath 111 can introduce the blood in the blood vessel into the inner cavity 1123 of the puncture needle base 112. The blood vessel can be an artery or a vein.

[0032] The puncture needle core 12 is specifically a hollow structure so as to draw out the blood in the blood vessel. One end (which may be called the front end) of the puncture needle core 12 is used for puncture, and the front end is a short bevel angle structure so as to improve the efficiency, accuracy and safety of puncture. The outer diameter of the puncture needle core 12 is smaller than the outer diameter of the puncture needle sheath 111, so the puncture needle core 12 can be inserted into the puncture needle sheath 111.

[0033] In some embodiments, a blood reservoir 121 is provided at the rear end of the puncture needle core 12. When the puncture needle core 12 punctures into a blood vessel, the blood in the blood vessel will quickly flow back to the blood reservoir 121, so that it is convenient to judge whether the puncture blood return state is normal based on the blood reservoir 121.

[0034] The puncture needle core 12 and the puncture needle body 11 are independently arranged structures. However, when the puncture needle 1 is in a standby state, Figure 2As shown, the puncture needle core 12 can pass through the puncture base 112 and the puncture needle sheath 111 through the infusion interface 1121, so that the blood reservoir 121 of the puncture needle core 12 forms a sealing structure with the infusion interface 1121. Inserting the puncture needle core 12 into the puncture needle body 11 makes it easier to store the puncture needle 1. When measuring blood pressure, the puncture needle body 11 with the puncture needle core 12 inserted is used for puncture. The short bevel angle structure of the puncture needle core 12 first punctures the blood vessel, and then guides the puncture needle sheath 111 sleeved on the puncture needle core 12 to puncture the blood vessel. When the puncture depth is appropriate, the puncture needle core 12 is pulled out of the puncture needle body 11 to complete the puncture operation. When the puncture needle core 12 is pulled out, the puncture base 112 needs to be pushed so that the puncture needle sheath 111 is still retained in the target blood vessel. At this time, since the puncture needle core 12 has been pulled out of the puncture needle body 11, the blood in the blood vessel will flow along the puncture needle sheath 111 to the inner cavity 1123 of the puncture needle base 112. Figure 3 shown.

[0035] In order to be able to perform blood pressure monitoring tasks in special environments such as functional MRI examinations during brain tumor surgery and MRI examinations for critically ill patients, the material of the puncture needle body 11 is selected to be non-metallic material, such as epoxy resin, and because the puncture needle core 12 will be pulled out before measurement, its material can be metal material, such as stainless steel and other metal materials with good biocompatibility. In addition, the material of the puncture needle core 12 can also be a non-metallic material that can meet medical grade requirements, such as high-performance ceramics.

[0036] In some embodiments, the puncture needle 1 further includes a protective cap (not shown in the figure). The protective cap can be used to seal the blood pressure measurement interface 1122 when the puncture needle 1 is in a standby state.

[0037] (2) Regarding the Fabry-Perot cavity optical fiber sensor 2, in some embodiments, as shown in the figure, it includes a sensor body 21, an optical fiber interface 22, and a medical device interface that matches the blood pressure measurement interface 1122 of the puncture needle 1.

[0038] The Fabry-Perot cavity optical fiber sensor 2 is connected to the blood pressure measurement interface 1122 of the puncture needle 1 through the medical device interface, and is connected to one end of the optical fiber transmission line 3 through the optical fiber interface, and the other end of the optical fiber transmission line 3 is connected to the photoelectric conversion regulator 4; when the medical device interface and the blood pressure measurement interface 1122 are in a connected state, the pressure sensitive end of the sensor body 21 (i.e., the end of the sensor close to the Fabry-Perot cavity) enters the inner cavity 1123 of the puncture base 112. Among them, the sensor body 21 can partially or completely enter the inner cavity 1123 of the puncture base 112.

[0039] In some embodiments, see Figure 4The sensor body 21 includes a two-stage sleeve 211 and a single-mode optical fiber 214; the single-mode optical fiber 214 includes a core 2141 and a cladding 2142; the single-mode optical fiber 214 is sealed and nested in the two-stage sleeve 211, and there is a micron-level optical cavity formed by laser technology between the two-stage sleeves 211. The corresponding two sides of the optical cavity are respectively coated with high-reflection films 212 (high-precision reflection films) by laser, one of which is close to the end face of the single-mode optical fiber and connected to the single-mode optical fiber, and the other high-reflection film 212 is away from the end face of the single-mode optical fiber 214 and close to the end face of the two-stage sleeve 211. The two high-reflection films 212 together with the air in the optical cavity form an optical Fabry-Perot cavity (FP cavity) 213, one of which is connected to the single-mode optical fiber 214 to emit laser and receive optical parameters, and transmit optical information back to the photoelectric conversion regulator 4 for data analysis.

[0040] In some embodiments, the single-mode optical fiber and the high-reflection film 212 in the sensor body 21 can be fixed on the two-stage sleeve 211 by non-toxic polymer UV glue.

[0041] In some embodiments, the periphery of the sensor body 21 is covered with a skin, such as Figure 5 As shown, the skin includes a coating layer 2143 and a protective layer 2144. The skin is further coated on the periphery of the sensor body 21 to increase the tensile, torsional and bending resistance of the sensor and improve its service life.

[0042] In some embodiments, the end surface of the two-stage sleeve 211 is connected with a high-precision sensitive diaphragm 215, so as to increase the sensitivity and accuracy of the sensor. Further, the sensitive diaphragm 215 is made of single crystal silicon or silicon dioxide diaphragm to improve the measurement accuracy. The sensitive diaphragm can be etched by semiconductor micro-electromechanical system technology.

[0043] In some embodiments, the Fabry-Perot cavity optical fiber sensor 2 further includes a protective cap (not shown in the figure) for protecting the pressure sensitive end. When the Fabry-Perot cavity optical fiber sensor 2 is not in use, the protective cap is installed at the front end of the Fabry-Perot cavity optical fiber sensor 2 to ensure the measurement accuracy of the Fabry-Perot cavity optical fiber sensor 2.

[0044] In some embodiments, the expansion coefficient of the material of the two-stage sleeve 211 is consistent with the expansion coefficient of the material of the single-mode optical fiber, so as to minimize the impact of temperature on the sensor.

[0045] In some embodiments, since the Fabry-Perot cavity optical fiber sensor 2 will directly contact with the patient's blood, based on medical safety and strict prevention and control of medical infection, the Fabry-Perot cavity optical fiber sensor 2 is disposable.

[0046] In some embodiments, the blood pressure measurement interface 1122 and the infusion interface 1121 are both Luer inner cone interfaces. Accordingly, the medical device port of the Fabry-Perot cavity optical fiber sensor 2 is a Luer outer cone interface, so that the blood pressure measurement interface 1122 can be fixedly connected to the medical device port.

[0047] In some embodiments, the periphery of the sensor body 21 is wrapped with a skin, so as to better protect the sensor body 21.

[0048] Further, in some embodiments, the outer periphery of the blood pressure measurement interface 1122 is provided with threads (not shown in the figure), and accordingly, the skin covering the front end of the sensor body is provided with a screw cap 216. Accordingly, the threads match the screw cap of the front end skin of the sensor body. When the Fabry-Perot cavity optical fiber sensor 2 is docked with the blood pressure measurement interface 1122, the reliability of docking can be improved by inserting the screw cap into the threads of the outer periphery of the blood pressure measurement interface 1122.

[0049] (3) The optical fiber transmission line 3 is connected to the Fabry-Perot cavity optical fiber sensor 2 and the photoelectric conversion regulator 4 through optical fiber interfaces provided at both ends.

[0050] In this embodiment, the optical fiber transmission line 3 is used for signal transmission, including transmitting the laser emitted by the photoelectric conversion regulator 4 and the optical signal reflected by the Fabry-Perot cavity optical fiber sensor 2. The number and length of the optical fiber transmission lines 3 can be bridged or customized according to specific clinical scenarios, and this embodiment does not impose any particular restrictions on this.

[0051] Considering that the optical fiber length of the Fabry-Perot cavity optical fiber sensor 2 is relatively limited, the present embodiment uses the optical fiber transmission line 3 for long-distance bridging, instead of directly connecting the Fabry-Perot cavity optical fiber sensor 2 to the photoelectric conversion regulator 4, so as to meet the actual needs of different clinical application scenarios and different monitoring distances. At the same time, unlike the Fabry-Perot cavity optical fiber sensor 2, the optical fiber transmission line 3 is reusable, rather than a disposable consumable, so as to reduce the cost of disposable consumables and reduce the burden on patients and medical institutions.

[0052] In some embodiments, the optical fiber transmission line 3 includes a core, a cladding, a coating layer, a protective layer, and ST-type optical fiber interfaces disposed at both ends.

[0053] The outer periphery of the fiber core is coated with a skin (composed of a coating layer and a protective layer), which can improve the corrosion resistance of the optical fiber transmission line 3, increase the bending performance, and improve the damage resistance such as tensile and torsion resistance.

[0054] In some embodiments, the material and refractive index of the optical fiber transmission line 3 are consistent with those of the Fabry-Perot cavity optical fiber sensor 2, which can reduce the attenuation of the optical signal during transmission and reduce the difference in optical signal transmission caused by different materials, thereby improving signal accuracy.

[0055] (4) A photoelectric conversion regulator 4, which is used to emit laser light to the Fabry-Perot cavity optical fiber sensor 2 and calculate blood pressure information based on optical information reflected by the Fabry-Perot cavity optical fiber sensor 2.

[0056] The photoelectric conversion regulator 4 includes a laser light source, a coupler, a photoelectric conversion chip and a high-speed data storage module.

[0057] The laser light source emits incident light of a specific wavelength, which is integrated by the coupler and transmitted to the Fabry-Perot cavity optical fiber sensor 2 through the optical fiber transmission line 3. The optical information is transmitted back after being reflected by the Fabry-Perot cavity optical fiber sensor 2. Under the squeeze of blood, the cavity length of the Fabry-Perot cavity in the Fabry-Perot cavity optical fiber sensor 2 changes, thereby changing the reflected optical parameters. After the optical information is transmitted back by the Fabry-Perot cavity optical fiber sensor 2, it is integrated by the coupler and transmitted to the photoelectric conversion chip. The photoelectric conversion chip converts the optical information into an electrical signal based on the pressure correlation and stores it in the high-speed data storage module.

[0058] Specifically, the light transmitted by the optical fiber transmission line 3 is vertically incident on the end face of the single-mode optical fiber 214 through the single-mode optical fiber 214 in the Fabry-Perot cavity optical fiber sensor 2. A portion of the optical power (about 4%) is reflected by the end face of the single-mode optical fiber 214. The remaining optical power is transmitted and reaches the high-reflection film, which is partially reflected by the inner surface of the high-reflection film and coupled back into the single-mode optical fiber 214. The reflected light from the end face of the single-mode optical fiber 214 and the reflected light from the inner surface of the high-reflection film interfere with each other. According to the principle of film elastic deformation, the high-reflection film set at the end face away from the single-mode optical fiber 214 is deformed under the squeezing effect of blood pressure, thereby changing the cavity length of the Fabry-Perot cavity and causing the interference spectrum to change. By measuring the interference spectrum and demodulating the interference spectrum, the pressure change acting on the high-reflection film set at the end face away from the single-mode optical fiber 214 can be obtained.

[0059] Among them, according to the principle of elastic mechanics, the relationship between pressure change and cavity length change can be expressed by the following formula:

[0060] Among them, Δp represents the change of the pressure difference between the inside and outside of the high-reflection film; h represents the thickness of the high-reflection film; r represents the effective radius of the high-reflection film; Δd represents the change of the length of the Fabry-Perot cavity; μ represents the Poisson's ratio of the high-reflection film; and E represents the Young's modulus of the high-reflection film.

[0061] In some embodiments, the photoelectric conversion regulator 4 may further include a processor and a display module. The processor may read the data in the high-speed data storage module and display the data visually through the display module.

[0062] In other embodiments, the photoelectric conversion regulator can be designed as a plug-in compatible with mainstream monitors, and then the photoelectric conversion chip converts the optical information into electrical signals according to the pressure correlation, and transmits these electrical signals to the compatible monitor through a preset transmission protocol, and the monitor displays the waveform and the measured blood pressure information (such as blood pressure value, etc.). In this embodiment, the plug-in photoelectric conversion regulator can realize the quick start application function in the form of hot plugging.

[0063] Based on the same inventive concept, the present application also provides a blood pressure measurement method, which is implemented based on the blood pressure measurement system provided by any of the above embodiments; in some embodiments, the method includes: Figure 6 The steps shown are described below.

[0064] S10: The puncture needle core is used to guide the puncture needle sheath to puncture into the target blood vessel, so that the blood in the target blood vessel flows into the inner cavity of the puncture base through the puncture needle sheath and directly contacts the pressure sensitive end of the sensor body in the Fabry-Perot cavity optical fiber sensor; the target blood vessel is an artery or a vein.

[0065] S20: The laser is emitted to the Fabry-Perot cavity optical fiber sensor through the photoelectric conversion regulator, and the blood pressure information is calculated according to the optical information reflected by the Fabry-Perot cavity optical fiber sensor.

[0066] In some embodiments, after the puncture needle sheath punctures into the target blood vessel, the method also includes the following steps: judging whether the blood return status after puncture is normal based on the blood storage tank of the puncture needle core; if the blood return status is normal, the puncture needle core is pulled out of the puncture needle body by pushing the puncture base, and the puncture needle sheath is left in the target blood vessel.

[0067] In the above embodiment, when blood pressure measurement is performed, the puncture needle body 11 with the puncture needle core 12 inserted is used for puncture. The short bevel angle structure of the puncture needle core 12 first punctures the blood vessel, and then guides the puncture needle sheath 111 sleeved on the puncture needle core 12 to puncture the blood vessel. When the puncture depth is appropriate, the puncture needle core 12 is pulled out of the puncture needle body 11 to complete the puncture operation. When the puncture needle core 12 is pulled out, the puncture base 112 needs to be pushed so that the puncture needle sheath 111 is still retained in the target blood vessel. At this time, since the puncture needle core 12 has been pulled out of the puncture needle body 11, the blood in the blood vessel will flow along the puncture needle sheath 111 to the inner cavity 1123 of the puncture needle base 112.

[0068] In the above embodiment, when blood pressure measurement is performed, the blood pressure measurement interface 1122 is a must-use interface, while the infusion interface 1121 can be used or not according to actual conditions.

[0069] In some embodiments, when the target blood vessel is a vein and the infusion interface of the puncture needle is connected to an infusion device, before emitting laser to the Fabry-Perot cavity fiber optic sensor through the photoelectric conversion regulator, the method also includes: closing the infusion regulating valve or tee to suspend fluid infusion.

[0070] The puncture needle has an infusion interface, so it can be used as an infusion line in addition to blood pressure measurement. Considering that the clinical measurement of venous blood pressure is usually to clarify the volume and right heart load, there is no need to continuously monitor venous pressure during infusion. Therefore, when the infusion interface is connected to the infusion device, if venous pressure measurement is required, the infusion should be suspended first, so as to improve the accuracy of the venous pressure measurement results.

[0071] In some embodiments, when the target blood vessel is an artery and the infusion interface of the puncture needle is connected to a pressurized flushing device, the method further includes: flushing the arterial line through the pressurized flushing device at regular or irregular intervals.

[0072] When the system (referring to the blood pressure measurement system) monitors arterial blood pressure, no fluid infusion is required. However, in some embodiments, when measuring arterial blood pressure, a pressurized flushing device can be connected through the infusion interface, and then the arterial line can be intermittently flushed through the pressurized flushing device during the measurement process. For example, Figure 7 As shown, the above-mentioned pressurized flushing device is connected to the infusion device and the pressurized bag through a three-way device, and the arterial line is intermittently flushed by timely connecting the three-way connector. This can prevent the puncture needle from being blocked, which is beneficial to ensure the final blood pressure measurement accuracy.

[0073] In some embodiments, before emitting laser to the Fabry-Perot cavity optical fiber sensor through the photoelectric conversion regulator, the method further includes: setting a zero point according to the patient's body position.

[0074] In the current invasive arteriovenous blood pressure measurement technology, the system needs to be zeroed before blood pressure measurement. System zeroing is usually to eliminate the existing pressure in the liquid-filled catheter system itself, which is a drawback of the existing arterial pressure measurement system. System zeroing requires rotating the tee to connect the pressure measurement pipeline to the atmosphere, which will destroy the airtightness of the pipeline; in addition, medical staff need to strictly implement hand hygiene and aseptic operation during operation, which increases the work pressure of medical staff and increases the risk of pipeline contamination. However, this embodiment does not require system zeroing (zero adjustment), only zero point setting.

[0075] In this embodiment, the zero point adjustment is set in the system. In addition to the conventional adjustment through the puncture point, the zero point can also be set directly through the system setting, and the methods are diverse and flexible. Especially in surgeries that require multiple body position changes, there is no need to open and close the three-way valve multiple times, and the zero point setting can be completed by only adjusting the system, so it can have the advantages of reducing contamination risks and reducing human errors.

[0076] Regarding the zero point setting, the arterial zero point is at the level of the left ventricle. When the patient is in a supine position, the hands are naturally placed flat on both sides of the body, and the radial artery height is approximately flush with the heart position. Therefore, in a supine position, the position where the hands are naturally placed flat can be considered the zero point position, and it can be set to zero point. In special body positions, such as head-high position or side-lying position, which causes a height difference between the heart and the puncture point, it can be adjusted in the following two ways.

[0077] Method 1: The puncture point is set at the zero position by abducting the patient's puncture hand so that it is flush with the heart.

[0078] Method 2: Measure the height difference between the puncture point and the heart and make adjustments in the system.

[0079] The correlation is that the blood density of the human body is 1.05-1.06 g / cm3. When the sensor is 1 cm lower than the zero point, it will generate about 1 cm H2O hydrostatic pressure, about 0.735 mmHg hydrostatic pressure. On the contrary, when the sensor is 1 cm higher than the zero point, it will generate about 1 cm H2O hydrostatic pressure. According to this relationship, when the puncture point is N cm lower than the heart position, the system setting sets the zero point to N cm below the heart. When the system measures the blood pressure, it will automatically subtract (0.735 * N) mmHg from the measured blood pressure value to obtain the actual blood pressure value. On the contrary, when the puncture point is M cm higher than the heart position, the system setting sets the zero point to M cm above the heart. When the system measures the blood pressure, it will automatically add (0.735 * M) mmHg to the measured blood pressure value to obtain the actual blood pressure value.

[0080] For specific limitations on the blood pressure measurement method, please refer to the above description of the blood pressure measurement system, which will not be repeated here.

[0081] Based on the same inventive concept, the present application also provides a puncture needle. In some embodiments, the puncture needle includes a puncture needle body and a puncture needle core, both of which are hollow structures.

[0082] The material of the puncture needle body is non-metallic The puncture needle body includes a puncture needle sheath and a puncture base; The front end of the puncture base is connected to the rear end of the puncture needle sheath; the rear end of the puncture base is provided with an infusion interface for connecting to an infusion tube and a blood pressure measurement interface for connecting to a Fabry-Perot cavity optical fiber sensor; The front end of the puncture needle core is a short bevel angle structure; the puncture needle core is used to guide the puncture needle sheath to puncture into a blood vessel, which is an artery or a vein; the puncture needle sheath is used to introduce blood in the blood vessel into the inner cavity of the puncture needle base.

[0083] In some embodiments, the blood pressure measurement interface and the infusion interface are both Luer cone interfaces.

[0084] In some embodiments, the outer circumference of the blood pressure measurement interface is provided with threads.

[0085] In some embodiments, a blood storage tank for determining the puncture blood return status is provided at the rear end of the puncture needle core.

[0086] In some embodiments, when the puncture needle is in a standby state, the puncture needle core passes through the puncture base and the puncture needle sheath through the infusion interface, so that the blood storage tank of the puncture needle core and the infusion interface form a sealing structure.

[0087] In some embodiments, the puncture needle further comprises a protective cap for sealing the blood pressure measurement interface.

[0088] For specific limitations on the puncture needle, please refer to the introduction to the puncture needle 1 in the above description of the blood pressure measurement system, which will not be repeated here.

[0089] It should be understood that each step in each embodiment of the present application is not necessarily performed in sequence according to the order indicated by the step number. Unless there is clear explanation in this article, the execution of these steps does not have strict order restriction, and these steps can be performed in other orders. Moreover, at least a part of the steps in each embodiment can include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a part of other steps or sub-steps or stages of other steps.

[0090] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as intravenous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink), DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0091] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0092] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A blood pressure measurement system, characterized in that: The system comprises a puncture needle, a Fabry-Perot cavity optical fiber sensor, an optical fiber transmission line and a photoelectric conversion regulator; The puncture needle comprises a puncture needle body and a puncture needle core, both of which are hollow structures; the material of the puncture needle body is non-metallic material; The puncture needle body comprises a puncture needle sheath and a puncture base; The front end of the puncture base is connected to the rear end of the puncture needle sheath; the rear end of the puncture base is provided with an infusion interface for connecting an infusion tube and a blood pressure measurement interface for connecting the Fabry-Perot cavity optical fiber sensor; The front end of the puncture needle core is a short bevel angle structure; the puncture needle core is used to guide the puncture needle sheath to puncture into a blood vessel, and the blood vessel is an artery or a vein; the puncture needle sheath is used to introduce the blood in the blood vessel into the inner cavity of the puncture needle base; The Fabry-Perot cavity optical fiber sensor comprises a sensor body, a medical device interface and an optical fiber interface matching the blood pressure measurement interface of the puncture needle; The Fabry-Perot cavity optical fiber sensor is connected to the blood pressure measurement interface of the puncture needle through the medical device interface, and is connected to one end of the optical fiber transmission line through the optical fiber interface, and the other end of the optical fiber transmission line is connected to the photoelectric conversion regulator; when the medical device interface and the blood pressure measurement interface are in a connected state, the pressure sensitive end of the sensor body enters the inner cavity of the puncture base; The photoelectric conversion regulator is used to emit laser to the Fabry-Perot cavity optical fiber sensor and calculate blood pressure information based on optical information reflected by the Fabry-Perot cavity optical fiber sensor.

2. The system according to claim 1, characterized in that The medical device port of the Fabry-Perot cavity optical fiber sensor is a Ruhr outer cone interface.

3. The system according to claim 1, characterized in that The outer periphery of the sensor body is wrapped with a skin.

4. The system according to claim 1, characterized in that The skin covering the front end of the sensor body is provided with a screw cap.

5. A blood pressure measurement method, characterized in that: The method is implemented based on the blood pressure measurement system according to any one of claims 1 to 4; the method comprises: The puncture needle core is used to guide the puncture needle sheath tube to puncture into a target blood vessel, so that the blood in the target blood vessel flows into the inner cavity of the puncture base through the puncture needle sheath tube and directly contacts the pressure sensitive end of the sensor body in the Fabry-Perot cavity optical fiber sensor; the target blood vessel is an artery or a vein; The photoelectric conversion regulator emits laser light to the Fabry-Perot cavity optical fiber sensor, and the blood pressure information is calculated according to the optical information reflected by the Fabry-Perot cavity optical fiber sensor.

6. The method according to claim 5, characterized in that After the puncture needle sheath is punctured into the target blood vessel, the method further includes: Judging whether the blood return state after puncture is normal based on the blood storage tank of the puncture needle core; If the blood return state is normal, the puncture needle core is pulled out of the puncture needle body by pushing the puncture base, and the puncture needle sheath is left in the target blood vessel.

7. The method according to claim 5, characterized in that When the target blood vessel is a vein and the infusion interface of the puncture needle is connected to an infusion device, before the photoelectric conversion regulator emits laser light to the Fabry-Perot cavity optical fiber sensor, the method further includes: Close the infusion regulating valve or three-way valve to suspend fluid infusion.

8. The method according to claim 5, characterized in that When the target blood vessel is an artery and the infusion interface of the puncture needle is connected to a pressurized flushing device, the method further includes: The arterial line is flushed regularly or irregularly by the pressurized flushing device.

9. The method according to claim 5, characterized in that Before emitting laser light to the Fabry-Perot cavity optical fiber sensor through the photoelectric conversion regulator, the method further includes: Set the zero point according to the patient's body position.

10. A puncture needle, characterized in that: The puncture needle comprises a puncture needle body and a puncture needle core, both of which are hollow structures; the material of the puncture needle body is non-metallic material; The puncture needle body comprises a puncture needle sheath and a puncture base; The front end of the puncture base is connected to the rear end of the puncture needle sheath; the rear end of the puncture base is provided with an infusion interface for connecting an infusion tube and a blood pressure measurement interface for connecting a Fabry-Perot cavity optical fiber sensor; The front end of the puncture needle core is a short bevel angle structure; the puncture needle core is used to guide the puncture needle sheath to puncture into a blood vessel, which is an artery or a vein; the puncture needle sheath is used to introduce blood in the blood vessel into the inner cavity of the puncture needle base.

11. The puncture needle according to claim 10, characterized in that: The blood pressure measurement interface and the infusion interface are both Luer cone interfaces.

12. The puncture needle according to claim 10, characterized in that: The outer periphery of the blood pressure measurement interface is provided with threads.

13. The puncture needle according to claim 11, characterized in that: The rear end of the puncture needle core is provided with a blood storage tank for judging the puncture blood return status.

14. The puncture needle according to claim 13, characterized in that: When the puncture needle is in a standby state, the puncture needle core passes through the puncture base and the puncture needle sheath through the infusion interface, so that the blood storage tank of the puncture needle core and the infusion interface form a sealing structure.

15. The puncture needle according to claim 10, characterized in that: The puncture needle also includes a protective cap for sealing the blood pressure measurement interface.

Images