Hemodialysis needle monitoring device and needle movement monitoring method

Abstract

The invention discloses a hemodialysis needle monitoring device and a needle movement monitoring method.The hemodialysis needle monitoring device comprises a needle body and needle wings fixedly connected to the two sides of the needle body, rectangular grooves parallel to the needle body are formed in the needle wings, and a copper sliding block is fixedly arranged in the middle of the top face of each rectangular groove; the strip-shaped resistor is fixed on the gasket and is parallel to the needle body; the bonding layer is arranged on the bottom surface of the gasket; the resistance value of the strip-shaped resistor is in direct proportion to the length of the strip-shaped resistor; the copper sliding block is in sliding connection with the strip-shaped resistor; and the alarm module is used for carrying out needle movement alarm according to a resistance value between the copper slide block and the end part of the strip-shaped resistor. The moving direction and the moving distance of the hemodialysis needle can be monitored in real time, an alarm can be given when the moving distance exceeds a set threshold value, in this way, medical staff can find the abnormal moving problem of the hemodialysis needle in time, and the problem that the hemodialysis needle penetrates through a blood vessel or retreats from the blood vessel can be avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to the technical field of hemodialysis needle monitoring. Background Art

[0002] Hemodialysis (HD) is one of the renal replacement therapies for patients with acute and chronic renal failure. Hemodialysis requires a dialysis needle to puncture into a blood vessel to drain the body's blood to the outside, and then through a dialyzer composed of countless hollow fibers. The blood and an electrolyte solution (dialysate) with a concentration similar to that of the body are exchanged through diffusion, ultrafiltration, adsorption, and convection principles inside and outside the hollow fibers to remove the body's metabolic wastes, maintain electrolyte and acid-base balance, and at the same time remove excess water in the body; Hemodialysis also requires a dialysis needle to puncture into a blood vessel to transfuse the purified blood back.

[0003] In the prior art, hemodialysis needles are generally fixed with adhesive tapes. Due to the poor adhesion reliability of the adhesive tapes, the hemodialysis needles are prone to displacement problems. If they shift inward, the hemodialysis needles may penetrate the blood vessel; if they shift outward, the hemodialysis needles may withdraw from the blood vessel. When performing hemodialysis, the punctured radial artery and cephalic vein are involved. The diameter of the radial artery is 3 - 4 mm, and the diameter of the cephalic vein is 5 - 6 mm; assuming that the tip of the hemodialysis needle is located in the middle of the blood vessel, then if the movement distance of the needle puncturing the radial artery exceeds 1.5 mm and the movement distance of the needle puncturing the cephalic vein exceeds 2.5 mm, problems such as the dialysis needle penetrating the blood vessel or withdrawing from the blood vessel may occur, which will affect the normal progress of hemodialysis. However, in the prior art, there is no good method to monitor the displacement amount of the hemodialysis needle. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a hemodialysis needle monitoring device and a needle movement monitoring method to solve the technical problem of monitoring the displacement amount of the hemodialysis needle and ensuring the stable operation of hemodialysis.

[0005] The hemodialysis needle monitoring device of the present invention includes a needle body and needle wings fixedly connected to both sides of the needle body. A rectangular groove parallel to the needle body is provided on the needle wings, and a copper slider is fixedly arranged in the middle of the top surface of the rectangular groove;

[0006] The hemodialysis needle monitoring device further includes a gasket, a strip-shaped resistor fixed on the gasket and parallel to the needle body, and an adhesive layer provided on the bottom surface of the gasket. The resistance value of the strip-shaped resistor is proportional to its length; the copper slider is slidably connected to the strip-shaped resistor;

[0007] The hemodialysis needle monitoring device further includes an alarm module for needle movement alarm according to the resistance value between the copper slider and the end of the strip-shaped resistor.

[0008] Further, the alarm module includes wires respectively connected to the copper slider and the rear end of the strip resistor, a current sensor for measuring the current in the wire, a single-chip microcomputer connected to the current sensor, a wireless transmitter connected to the single-chip microcomputer for transmitting an alarm signal, and a regulated power supply for supplying power to the circuit.

[0009] The present invention also discloses a method for monitoring the movement of a blood dialysis needle of a blood dialysis needle monitoring device, which includes:

[0010] 1) After the needle body penetrates into the blood vessel, paste the gasket on the skin and bond the needle wing to the skin through tape;

[0011] 2) Measure the initial resistance: Turn on the regulated power supply, measure the current in the wire through the current sensor, and then the single-chip microcomputer calculates the initial resistance from the copper slider to the rear end of the resistor according to the voltage of the regulated power supply and the current in the wire. The calculation formula is as follows:

[0012]

[0013] Among them, R ref is the initial resistance from the copper slider to the rear end of the resistor, V is the voltage of the regulated power supply, and I is the current in the wire;

[0014] 3) The single-chip microcomputer performs real-time needle movement monitoring and alarm:

[0015] The single-chip microcomputer calculates the real-time resistance from the copper slider to the rear end of the resistor according to the voltage of the regulated power supply and the real-time current in the wire. The calculation formula is as follows:

[0016]

[0017] Among them, R real is the real-time resistance from the copper slider to the rear end of the resistor, I real is the real-time current in the wire;

[0018] Calculate the difference R between the real-time resistance and the true resistance through the following formula Δ :

[0019] R Δ = R real - R reaf

[0020] If R Δ is positive, it means the needle body is moving outwards; if R Δ is negative, it means the needle body is moving inwards;

[0021] Calculate the distance L of the needle body movement through the following formula:

[0022] L = mR Δ ,

[0023] Among them, m is the displacement coefficient, representing the length corresponding to the unit resistance;

[0024]

[0025] Among them, L 总 is the total length of the bar resistor, and R 总 is the overall resistance value of the bar resistor;

[0026] If the moving distance in the needle body exceeds the set threshold, the single-chip microcomputer outputs an alarm signal, and the alarm signal is sent to the monitoring terminal through the wireless transmitter.

[0027] Advantages of the present invention:

[0028] The blood dialysis needle monitoring device and the needle movement monitoring method of the present invention can monitor the moving direction and moving distance of the blood dialysis needle in real time, and can alarm when the moving distance exceeds the set threshold, so that medical staff can timely discover the abnormal movement problem of the blood dialysis needle, which is beneficial to avoiding the problems of the blood dialysis needle penetrating the blood vessel or withdrawing from the blood vessel. Description of the drawings

[0029] Figure 1 is a schematic structural diagram of the blood dialysis needle monitoring device.

[0030] Figure 2 is Figure 1 the cross-sectional structural diagram along A-A in

[0031] Figure 3 is Figure 1 the cross-sectional structural diagram along B-B in Specific implementation manners

[0032] The present invention will be further described below with reference to the drawings and embodiments.

[0033] As shown in the figure, the blood dialysis needle monitoring device of this embodiment includes a needle body 1 and needle wings 2 fixedly connected to both sides of the needle body. A rectangular groove 3 parallel to the needle body is provided on the needle wings, and a copper slider 4 is fixedly provided in the middle of the top surface of the rectangular groove.

[0034] The blood dialysis needle monitoring device further includes a gasket 5, a bar resistor 6 fixed on the gasket and parallel to the needle body, and an adhesive layer 7 provided on the bottom surface of the gasket. The resistance value of the bar resistor is proportional to its length; the copper slider is slidably connected to the bar resistor. In specific implementation, the cross-section of the bar resistor 6 can be made T-shaped to avoid the separation problem between the copper slider 4 and the bar resistor 6.

[0035] The blood dialysis needle monitoring device further includes an alarm module for needle movement alarm according to the resistance value between the copper slider and the end of the bar resistor. In this embodiment, the alarm module includes a wire 8 respectively connected to the copper slider and the rear end of the bar resistor, a current sensor 9 for measuring the current in the wire, a single-chip microcomputer 10 connected to the current sensor, a wireless transmitter 11 connected to the single-chip microcomputer for transmitting an alarm signal, and a regulated power supply 12 for supplying power to the circuit. In this embodiment, the current sensor 9 adopts a Hall current sensor.

[0036] The method for monitoring needle movement of the blood dialysis needle monitoring device in the above embodiment includes:

[0037] 1) After the needle body 1 penetrates into the blood vessel, the gasket 5 is pasted on the skin through the adhesive layer 7, and the needle wing 2 is adhesively fixed on the skin through the tape.

[0038] 2) Measure the initial resistance: Turn on the regulated power supply 12, measure the current in the wire 8 through the current sensor 9, and then the single-chip microcomputer calculates the initial resistance from the copper slider to the rear end of the resistor according to the voltage of the regulated power supply and the current in the wire. The calculation formula is as follows:

[0039]

[0040] Among them, R ref is the initial resistance from the copper slider to the rear end of the resistor, V is the voltage of the regulated power supply, and I is the current in the wire. Since the resistance of the copper slider 4 and the wire 8 is very small, when calculating R ref , the resistance of the copper slider 4 and the wire 8 can be ignored.

[0041] 3) The single-chip microcomputer performs real-time needle movement monitoring and alarm:

[0042] The single-chip microcomputer calculates the real-time resistance from the copper slider to the rear end of the resistor according to the voltage of the regulated power supply and the real-time current in the wire. The calculation formula is as follows:

[0043]

[0044] Among them, R real is the real-time resistance from the copper slider to the rear end of the resistor, and I real is the real-time current in the wire. Calculate the difference R Δ between the real-time resistance and the true resistance through the following formula:

[0045] R Δ = R real - R reaf

[0046] If R Δ is positive, it means the needle body is moving outwards; if R Δ is negative, it means the needle body is moving inwards.

[0047] The distance L of the needle body movement is calculated by the following formula:

[0048] L = mR Δ ,

[0049] where m is the displacement coefficient, representing the length corresponding to the unit resistance;

[0050]

[0051] where L 总 is the total length of the strip resistor, and R 总 is the overall resistance value of the strip resistor.

[0052] If the moving distance of the needle body exceeds the set threshold, the single-chip microcomputer outputs an alarm signal, and the alarm signal is sent to the monitoring terminal through the wireless transmitter. The alarm threshold can be set according to the diameter of the patient's blood vessel. For example, if the diameter of the radial artery is 3 - 4 mm, the alarm threshold can be set at 1.5 mm; if the diameter of the cephalic vein is 5 - 6 mm, the alarm threshold can be set at 2.5 mm. In a specific implementation, the alarm signal can include information such as the patient's bed number, patient name, needle movement direction, needle movement distance, etc., and the alarm terminal can be an audible and visual alarm set at the nurse station.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A hemodialysis needle monitoring device, comprising a needle body and needle wings fixedly connected to both sides of the needle body, characterized in that: The needle wing is provided with a rectangular groove parallel to the needle body, and a copper slider is fixedly provided in the middle of the top surface of the rectangular groove; The hemodialysis needle monitoring device also includes a gasket, a strip resistor fixed on the gasket and parallel to the needle body, and an adhesive layer arranged on the bottom surface of the gasket, wherein the resistance value of the strip resistor is proportional to its length; the copper slider is slidably connected to the strip resistor; The hemodialysis needle monitoring device also includes an alarm module for alarming needle movement according to the resistance value between the copper slider and the end of the strip resistor.

2. The hemodialysis needle monitoring device according to claim 1, characterized in that: The alarm module includes wires connected to the copper slider and the rear end of the strip resistor respectively, a current sensor for measuring the current in the wire, a single-chip microcomputer connected to the current sensor, a wireless transmitter connected to the single-chip microcomputer for transmitting an alarm signal, and a voltage-stabilized power supply for supplying power to the circuit.

3. The needle movement monitoring method of the hemodialysis needle monitoring device according to claim 2, characterized in that: include: 1) After the needle punctures the blood vessel, the gasket is pasted on the skin and the needle wings are fixed on the skin by adhesive tape; 2) Measure the initial resistance: Turn on the regulated power supply, measure the current in the wire through the current sensor, and then the microcontroller calculates the initial resistance from the copper slider to the rear end of the resistor based on the voltage of the regulated power supply and the current in the wire. The calculation formula is as follows: Among them, R ref is the initial resistance from the copper slider to the rear end of the resistor, V is the voltage of the regulated power supply, and I is the current in the wire; 3) The single chip microcomputer monitors the needle movement in real time and gives an alarm: The microcontroller calculates the real-time resistance from the copper slider to the rear end of the resistor based on the voltage of the regulated power supply and the real-time current in the wire. The calculation formula is as follows: Among them, R real is the real-time resistance from the copper slider to the rear end of the resistor, I real is the real-time current in the wire; The difference R between the real resistance and the actual resistance is calculated by the following formula Δ : R Δ =R real -R reaf If R Δ is positive, indicating that the needle is moving outward; if R Δ If it is negative, it means the needle is moving inward; The distance L that the needle moves is calculated by the following formula: L=mR Δ , Among them, m is the displacement coefficient, which represents the length corresponding to unit resistance; Among them, L 总 is the total length of the strip resistor, R 总 is the overall resistance value of the strip resistor; If the distance moved in the needle body exceeds the set threshold, the microcontroller outputs an alarm signal, which is sent to the monitoring terminal via a wireless transmitter.

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