Urethral catheter with urethral stress response monitoring function

Abstract

The invention discloses a urethral catheter with a urethral stress response monitoring function, which comprises a catheter body, a microelectrode array is arranged on the catheter body, the distance between the microelectrode array and a catheter head is 8-12mm, the microelectrode array comprises a plurality of annular electrodes which are sequentially arranged, a signal line is arranged on the catheter body, and the signal line is connected with the microelectrode array. One end of the signal line is sequentially connected with the annular electrode, the other end of the signal line is connected with the handheld control unit, and the handheld control unit comprises an excitation source module, an impedance analysis module and a signal prompt module. According to the urethral catheter, the microelectrode array is combined with a Cole-Cole model impedance analysis algorithm, real-time accurate monitoring of urethral stress reaction and a phase angle variation grading prompting mechanism are achieved, medical staff can visually master the reaction degree, and traditional subjective judgment errors are avoided.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a urinary catheter with urethral stress response monitoring function. Background Technology

[0002] In current clinical practice, monitoring pain caused by catheterization mainly relies on subjective pain rating scales, such as the Visual Analogue Scale (VAS). This method is affected by various factors such as individual patient differences, cognitive level, and emotional state, and lacks objective and accurate quantitative indicators, making it difficult to truly reflect the actual degree of urethral stress response. Existing studies have confirmed that the degree of urethral smooth muscle spasm is significantly positively correlated with changes in bioimpedance (Zhang L, et al. J Urol Res. 2023;10(2):45-51), which provides a theoretical basis for monitoring catheterization pain through bioimpedance technology. However, existing catheter products do not integrate this monitoring function, failing to meet the clinical need for objective pain assessment.

[0003] Patent CN201520883U discloses a catheter that uses a pressure sensor to monitor urethral resistance, but it can only detect macroscopic pressure changes in the urethral lumen and cannot capture the micro-stress response of the urethral mucosa caused by stimulation. This micro-stress is often an early signal of pain (Wang Lijuan, Zhang Min. Biomechanical research progress on catheter-related urethral injury [J]. China Medical Devices Journal, 2022, 46(3):312-315). US Patent US2017 / 0252051A1 proposes to predict the risk of catheter-related infection through temperature sensing. Its technical focus is on infection prevention, but it does not solve the problem of monitoring immediate pain during catheterization. Summary of the Invention

[0004] This invention addresses the shortcomings of existing catheterization pain assessment methods, which rely on subjective scoring and lack objective quantitative indicators, by achieving accurate and objective assessment of pain induced during catheterization. It overcomes the limitation of traditional catheters in providing real-time feedback on urethral stress, capturing early stress responses in the urethral mucosa and smooth muscle, and providing timely guidance for clinical procedures.

[0005] The technical solution adopted in this invention is: a urinary catheter with urethral stress response monitoring function. The urinary catheter includes a tube body, one end of which is provided with an air balloon and a catheter head in sequence, and the other end of which is provided with an outlet and an inlet. A water inlet valve is installed at the inlet. A micro-electrode array is provided on the tube body, and the distance between the micro-electrode array and the catheter head is 8-12 mm. The micro-electrode array includes several ring electrodes arranged in sequence. The ring electrodes are sleeved on the tube body. A signal line is provided on the tube body. One end of the signal line is connected to the ring electrodes in sequence, and the other end is connected to a handheld control unit. The handheld control unit includes an excitation source module, an impedance analysis module, and a signal prompt module. The excitation source module provides a detection excitation signal, the impedance analysis module analyzes the complex impedance data collected by the micro-electrode array, and the signal prompt module issues a prompt signal based on the analysis data of the impedance analysis module.

[0006] As a preferred embodiment of the above technical solution, the impedance analysis module constructs an impedance analysis algorithm based on the Cole-Cole model. By collecting the complex impedance data of the microelectrode array, it calculates the phase angle change Δθ. The signal prompt module includes a red LED, a yellow LED, and a green LED. When Δθ≦5°, the green LED lights up; when 5°≦Δθ≦15°, the yellow LED lights up; and when Δθ>15°, the red LED lights up.

[0007] As a preferred embodiment of the above technical solution, the signal prompting module further includes a buzzer.

[0008] As a preferred embodiment of the above technical solution, the excitation source module uses a 50kHz sine wave as the detection excitation signal, and the output voltage range is ±1V.

[0009] As a preferred embodiment of the above technical solution, a set of annular electrodes is provided between the balloon and the urinary catheter head.

[0010] As a preferred embodiment of the above technical solution, the number of signal lines is three, the three signal lines are spirally wound around the tube body, the tube body is provided with spiral grooves for the signal lines to be embedded, and the annular electrode is welded to the three signal lines respectively.

[0011] As a preferred embodiment of the above technical solution, the microelectrode array includes four sets of ring electrodes, which are made of medical-grade platinum. Each set of electrodes has a width of 0.5 mm and an electrode spacing of 2 mm.

[0012] As a preferred embodiment of the above technical solution, the signal line is connected to the handheld control unit via a quick-connect plug.

[0013] The beneficial effects of this invention are as follows: This urinary catheter, through the combination of a microelectrode array and a Cole-Cole model impedance analysis algorithm, achieves real-time and accurate monitoring of urethral stress response. The phase angle change grading indicator mechanism allows medical staff to intuitively grasp the degree of response, avoiding errors from traditional subjective judgment. The medical platinum ring electrode has good biocompatibility, and the spirally wound signal wire is easy to install and remove and highly adaptable, reducing usage costs. The 50kHz safe excitation signal balances detection effectiveness and human safety, and dynamic baseline calibration eliminates environmental interference, improving data reliability. Monitoring can be initiated during catheterization, and the early warning mechanism promptly alerts to risks, reducing complications such as urinary leakage and infection, improving patient comfort, and providing a scientific basis for clinical catheterization procedures and postoperative care. It is both practical and innovative. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a structural schematic diagram of the present invention from another perspective. Detailed Implementation

[0015] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0017] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0018] like Figure 1-2As shown, a urinary catheter with urethral stress response monitoring function includes a tube body 1. One end of the tube body 1 is provided with an air balloon 2 and a catheter head 3 in sequence. The other end of the tube body 1 is provided with an outlet 4 and an inlet 5. An inlet valve is installed at the inlet 5. A microelectrode array is provided on the tube body 1. The distance between the microelectrode array and the catheter head 3 is 8-12 mm. The microelectrode array includes several ring electrodes 6 arranged in sequence. The ring electrodes 6 are sleeved on the tube body 1. A signal line 7 is provided on the tube body 1. One end of the signal line 7 is connected to the ring electrodes 6 in sequence, and the other end is connected to a handheld control unit 13. The handheld control unit 13 includes an excitation source module, an impedance analysis module, and a signal prompt module. The excitation source module provides a detection excitation signal, the impedance analysis module analyzes the complex impedance data collected by the microelectrode array, and the signal prompt module issues a prompt signal based on the analysis data of the impedance analysis module.

[0019] Furthermore, the impedance analysis module constructs an impedance analysis algorithm based on the Cole-Cole model. By collecting the complex impedance data of the microelectrode array, it calculates the phase angle change Δθ. The signal prompt module includes a red LED 8, a yellow LED 9, and a green LED 10. When Δθ≦5°, the green LED 10 lights up; when 5°≦Δθ≦15°, the yellow LED 9 lights up; and when Δθ>15°, the red LED 8 lights up. An impedance analysis algorithm based on the Cole-Cole model is used. This model is a classic model for biological tissue impedance analysis. Its complex impedance expression is: \( Z(\omega) = R_{\infty}+\frac{R_0- R_{\infty}}{1+(j\omega\tau)^{\alpha}} \), where: \( Z(\omega) \) is the complex impedance (containing the real part \( R \) and the imaginary part \( X \) of the impedance), \( R_{\infty} \) is the high-frequency limiting impedance (the impedance value when the tissue capacitance is short-circuited at a frequency \( \omega \to \infty \)), \( R_0 \) is the low-frequency limiting impedance (the impedance value when the tissue capacitance is open-circuited at a frequency \( \omega \to 0 \)), \( \tau \) is the characteristic time constant, \( \alpha \) is the dispersion coefficient (reflecting the frequency dispersion of tissue impedance, with a value range of 0-1), \( j \) is the imaginary unit, \( \omega = 2\pif\) is the angular frequency (\( f = 50kHz\) is the excitation signal frequency).

[0020] The specific implementation steps of the algorithm are as follows: ① Data preprocessing: The raw data of complex impedance acquired by the signal acquisition unit is filtered. A 5th order Butterworth low-pass filter (cutoff frequency 100Hz) is used to eliminate high-frequency noise. At the same time, outliers are removed by a sliding window (the window size is set to 3 data points. When a data point deviates from the mean value in the window by more than ±3σ, it is judged as an outlier and replaced with the mean value). ② Parameter Identification: The preprocessed complex impedance data were fitted using the nonlinear least squares method (Levenberg-Marquardt algorithm) to solve for the four parameters \( R_{\infty} \), \( R_0 \), \( \tau\), and \( \alpha \) in the Cole-Cole model. The fitting objective was to minimize the mean square error of the real and imaginary parts of the complex impedance (\(MSE=\frac{1}{N}\sum_{i=1}^{N}[(R_i - \hat{R}_i)^2+(X_i - \hat{X}_i)^2] \), where \(R_i, X_i \) are measured values, \( \hat{R}_i, \hat{X}_i \) are calculated values ​​from the model, and \( N \) is the number of data points). ③ Phase angle calculation: Calculate the phase angle \( \theta = \arctan(-X / R) \) based on the fitted complex impedance value, and calculate the phase angle change \( \Delta\theta=|\theta - \theta_0| \) by comparing it with the initial baseline phase angle \( \theta_0 \) collected within 5 seconds before the catheterization operation (taking the average value of the phase angle within 5 seconds); ④ Dynamic calibration: Considering the baseline drift that may be caused by the urethral environment (such as urine residue and mucosal secretions), the algorithm automatically updates the baseline phase angle \( \theta_0'\) every 2 seconds, with the update rule being \(\theta_0'=0.8\theta_0+0.2\theta_{\text{current}}\) (\( \theta_{\text{current}} \) is the phase angle at the current moment), ensuring that the baseline always matches the actual urethral environment during the monitoring process; When (Delta > 15°), the system automatically triggers an early warning mechanism, indicating that the urethral stress response has reached a moderate or higher level.

[0021] Furthermore, the signal prompt module also includes a buzzer. When Δθ > 5°, the buzzer emits a sound to provide an alert. When Δθ > 15°, the buzzer sounds more compactly and at a higher frequency.

[0022] Furthermore, the excitation source module uses a 50kHz sine wave as the detection excitation signal, with an output voltage range of ±1V. The voltage complies with the safety standards for medical electrical equipment, ensuring no risk of electric shock to the human body. At the same time, the 50kHz frequency effectively balances signal penetration depth and interference suppression capability, reducing the influence of skin and subcutaneous tissue on impedance detection.

[0023] Furthermore, a set of annular electrodes 6 is provided between the balloon 2 and the catheter tip 3. The annular electrodes 6 between the balloon 2 and the catheter tip 3 provide detection during the catheterization process, generating a detection signal to assist in the catheterization process.

[0024] Furthermore, the number of signal wires 7 is three, which are spirally wound around the tube body 1. The tube body 1 has spiral grooves 11 for embedding the signal wires 7, and the annular electrode 6 is welded to each of the three signal wires 7. The three signal wires 7 are equidistantly arranged, forming a spiral pattern on the tube body 1, which facilitates the rotation of the catheter for insertion. The spiral grooves 11 ensure that the signal wires 7 fit snugly against the tube body 1, and the signal wires 7 and the microelectrode array can be easily installed and removed, allowing for long-term and repeated use with different tube bodies 1.

[0025] Furthermore, the microelectrode array includes four sets of ring electrodes 6, which are made of medical-grade platinum. Each set of electrodes is 0.5 mm wide, and the electrode spacing is 2 mm. Platinum has good biocompatibility and conductivity. The total length of the electrode array is 7 mm, ensuring multi-point signal acquisition within a limited space and improving the spatial resolution of the monitoring.

[0026] Furthermore, the signal line 7 is connected to the handheld control unit 13 via a quick-connect plug 12. The quick-connect plug 12 facilitates quick disassembly or docking, allowing the monitoring component to be quickly installed and removed.

[0027] It is worth mentioning that the technical features such as the Cole-Cole model involved in this patent application should be regarded as prior art. The specific structure, working principle, and possible control methods and spatial arrangement methods of these technical features can be adopted using conventional choices in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated in detail.

[0028] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make many modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning or limited experimentation on the basis of the prior art should be within the scope of protection defined by the claims.

Claims

1. A urinary catheter with urethral stress response monitoring function, comprising a tube body, one end of which is sequentially provided with a balloon and a catheter tip, and the other end of which is provided with an outlet and an inlet, wherein an inlet valve is installed at the inlet, characterized in that, The tube body is equipped with a microelectrode array, with a distance of 8-12 mm between the microelectrode array and the catheter tip. The microelectrode array includes several sequentially arranged ring electrodes, which are fitted onto the tube body. The tube body is equipped with signal lines, one end of which is connected to the ring electrodes sequentially, and the other end is connected to a handheld control unit. The handheld control unit includes an excitation source module, an impedance analysis module, and a signal prompt module. The excitation source module provides a detection excitation signal, the impedance analysis module analyzes the complex impedance data collected by the microelectrode array, and the signal prompt module issues a prompt signal based on the analysis data of the impedance analysis module. The impedance analysis module constructs an impedance analysis algorithm based on the Cole-Cole model, and calculates the phase angle change Δθ by collecting the complex impedance data of the microelectrode array. The signal prompt module includes a red LED, a yellow LED, and a green LED. When Δθ≦5°, the green LED lights up; when 5°≦Δθ≦15°, the yellow LED lights up; and when Δθ>15°, the red LED lights up. The excitation source module uses a 50kHz sine wave as the detection excitation signal, and the output voltage range is ±1V.

2. The urinary catheter with urethral stress response monitoring function as described in claim 1, characterized in that, The signal prompt module also includes a buzzer.

3. The urinary catheter with urethral stress response monitoring function as described in claim 1, characterized in that, A set of ring electrodes is provided between the balloon and the catheter tip.

4. The urinary catheter with urethral stress response monitoring function as described in claim 1, characterized in that, The number of signal lines is three. The three signal lines are spirally wound around the tube body, and the tube body is provided with spiral grooves for the signal lines to be embedded. The annular electrode is welded to the three signal lines respectively.

5. The urinary catheter with urethral stress response monitoring function as described in claim 4, characterized in that, The microelectrode array includes four sets of ring electrodes, which are made of medical-grade platinum. Each set of electrodes is 0.5 mm wide and the electrode spacing is 2 mm.

6. The urinary catheter with urethral stress response monitoring function as described in claim 1, characterized in that, The signal line is connected to the handheld control unit via a quick-connect plug.

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