A cerebrospinal fluid drainage circuit capable of accurately measuring pressure and intermittently controlling drainage

Abstract

A cerebrospinal fluid drainage pipeline capable of accurately measuring pressure and intermittently controlling drainage, mainly comprising an intraventricular drainage catheter (1), a three-way connector (2), an extraventricular drainage catheter (6), an ear canal positioning device (5), a pressure monitoring module (3), a transition joint (7) and a catheter clamp (8). The beneficial effects of the disclosed embodiment are: the pressure measurement baseline of the cerebrospinal fluid volume pressure can be accurately located, thereby improving the accuracy of cerebrospinal fluid volume pressure monitoring. At the same time, according to the set cerebrospinal fluid volume pressure threshold, the drainage pipeline is opened to achieve intermittent drainage, thereby improving the safety of cerebrospinal fluid drainage.

Description

Technical Field

[0001] The disclosed embodiment relates to a cerebrospinal fluid drainage pipeline capable of accurate pressure measurement and intermittent drainage control, which is a disposable sterile medical device. Background Art

[0002] After a brain-injured patient has a cerebellar hemorrhage, the brain tissue will be compressed by a large amount of hematoma, causing neurological dysfunction, which can cause the patient to fall into a coma or die in severe cases. Drainage of cerebrospinal fluid for patients with brain injury is one of the most commonly used clinical treatment techniques in neurosurgery. Its main purpose is to drain the bloody or contaminated cerebrospinal fluid outside the skull. For patients with external cerebrospinal fluid drainage, the patient's intracranial pressure (ICP) must be strictly monitored. If drainage is not performed in time, it will cause increased intracranial pressure. However, if the drainage volume is too large, it will further aggravate the symptoms of low intracranial pressure, and even cause serious complications such as epidural hemorrhage and brain herniation, endangering the patient's life.

[0003] Dynamic monitoring of intracranial pressure (ICP) is an effective means of monitoring, but the use of existing intracranial pressure monitoring equipment and fiber optic pressure measurement catheters for intracranial pressure monitoring not only has high technical barriers and harsh application conditions, but also the price of monitoring equipment and supporting consumables is very expensive, which is not conducive to popularization. In my country, the method of setting the hanging height of the drainage bottle is usually adopted to control the cerebrospinal fluid outflow pressure to maintain a relatively stable cerebrospinal fluid volume pressure, thereby maintaining the basic stability of the intracranial pressure of the drainage patient. The specific method is: hang the ventricular drainage bottle at the bedside of the drainage patient, and use a ruler to accurately measure so that the highest point of the drainage tube is 15cm higher than the plane of the lateral ventricle or 20cm above the horizontal baseline of the external auditory canal to maintain a stable cerebrospinal fluid volume pressure, which is usually 20cmH2O. Although this method has low consumables cost, the patient needs to adjust the bedside height frequently after surgery, which changes the original set cerebrospinal fluid volume pressure measurement baseline, and the cerebrospinal fluid volume pressure maintained by the drainage patient also changes. This requires re-measuring the hanging height of the drainage bottle every time the height of the bedside is adjusted, which increases a lot of nursing workload. Moreover, this drainage technology cannot dynamically and quantitatively monitor the volume and pressure of intracranial fluid accumulation in patients, and there is a large blind spot in monitoring. At the same time, continuous open drainage can easily cause bacteria in the drainage line or cerebrospinal fluid collection container to retrograde and ascend, increasing the patient's risk of infection and affecting the effectiveness and safety of cerebrospinal fluid drainage. Therefore, there is an urgent need for a new technical solution that can automatically locate the cerebrospinal fluid volume and pressure measurement baseline, quantitatively monitor the dynamic pressure of cerebrospinal fluid volume, and realize intermittent open drainage according to pressure changes, so as to overcome the shortcomings of existing clinical technology. Summary of the invention

[0004] The disclosed embodiment aims to overcome the shortcomings of the existing cerebrospinal fluid drainage technology and propose a new technical solution. The disclosed embodiment proposes a cerebrospinal fluid drainage pipeline that can accurately measure pressure and intermittently control drainage, which is mainly composed of an intraventricular drainage catheter, a three-way connector, an extraventricular drainage catheter, an ear canal positioning device, a pressure monitoring module, a transition joint and a catheter clamp.

[0005] The intraventricular drainage catheter is a flexible pipeline that is inserted into the patient's ventricle and drains cerebrospinal fluid to the outside of the brain. The head of the intraventricular drainage catheter is provided with a drainage hole. Depending on the use of adults or children, the physical dimensions of the intraventricular drainage catheter are provided with a variety of specifications, usually, for example, a length of 200 to 450 mm, an inner diameter of 0.8 to 3.0 mm, and an outer diameter of 1.8 to 4.5 mm. In order to avoid clogging of the drainage holes, the head of the intraventricular drainage catheter can be provided with multiple drainage holes, for example, a punching device is used to prepare 2 to 6 drainage holes in the 0 to 30 mm pipeline at the front end of the intraventricular drainage catheter; according to the different diameters of the drainage pipeline, the inner diameter of the drainage hole is selected between 0.5 and 2.0 mm. The intraventricular drainage catheter is produced by extrusion, slitting, punching and marking of medical polymer materials, for example, medical polymer materials such as polyvinyl chloride, polyurethane and silicone rubber are used.

[0006] The three-way connector is used for the connection and communication of the three components of the intraventricular drainage catheter, the extraventricular drainage catheter and the pressure monitoring module. The specific method of connection and communication is that the upstream interface of the three-way connector is connected to the tail of the intraventricular drainage catheter, the downstream interface of the three-way connector is connected to the head of the extraventricular drainage catheter, and the other interface of the three-way connector is connected to the pressure measuring port of the pressure monitoring module. The three-way connector is usually prepared by injection molding of medical polymer materials, and the specific shape is not limited, such as being prepared into a T shape or a Y shape. Due to the complex composition of cerebrospinal fluid, which contains blood, protein, etc., in actual clinical applications, if the cerebrospinal fluid is in direct contact with the pressure measuring port of the pressure monitoring module, the cerebrospinal fluid is easy to block the pressure measuring port, causing the pressure monitoring to fail or affecting the pressure measuring accuracy. Therefore, the preferred technical solution is that the three-way connector and the pressure measuring port of the pressure monitoring module are provided with an extension pipeline, and the extension pipeline physically isolates the drained cerebrospinal fluid from the pressure measuring port of the pressure monitoring module. Optional specific practices include, for example, using an extension catheter for connection. The extension catheter is 3 to 10 cm long and is made of medical polymer materials. The extension catheter is tightly connected to the three-way connector and the pressure measuring port of the pressure monitoring module. In clinical applications, the air in the extension catheter cannot be discharged, and the air inside the pipeline becomes a clean physical medium, effectively blocking body fluids from contacting or entering the pressure measuring port of the pressure sensor, thereby achieving the technical purpose of the pressure measuring port of the pressure sensor from being blocked. At the same time, since the air inside the pipeline is basically constant, it can also meet the requirements of pressure monitoring accuracy. Optional specific practices for setting up an extension pipeline include, for example, setting an S-shaped curved passage between the three-way connector and the pressure measuring port of the pressure monitoring module. The length of the S-shaped curved passage is 5 to 8 cm.

[0007] The outer periphery of the rear end of the intraventricular drainage catheter is provided with an ear canal positioning device, and the shape of the ear canal positioning device adopts a bionic structure, for example, a nipple protrusion that can be placed in the ear canal for fixing, or a hook fixed on the outer contour of the ear, which is close to the shape structure of existing earphones, earplugs, etc. The preferred technical solution is that the ear canal positioning device is moved and fixed on the outer periphery of the intraventricular drainage catheter to meet the needs of fixing and positioning of different head shapes. For example, the ear canal positioning device adopts a clip-type design, and according to the different characteristics of the patient's head size, it is fixed on the outer periphery of the intraventricular drainage catheter horizontally facing the patient's ear canal by using a clip; for another example, the ear canal positioning device adopts a slide rail design, which can slide on the outer periphery of the intraventricular drainage catheter, and when it slides to the position horizontally facing the patient's ear canal, it is fixed with medical tape. The main technical feature of the ear canal positioning device is that the ear canal positioning device and the pressure monitoring module are arranged on the same horizontal line; or after the ear canal positioning device is fixed on the patient's head, the pressure measuring port of the pressure monitoring module is on the same horizontal line with the center of the patient's ear canal. The ear canal positioning device is suitable for pressure measurement and positioning of supine patients. Obviously, depending on the patient's body position or puncture and drainage site, the ear canal positioning device can also position and measure pressure at other positions of the patient's head. For example, when the patient is in a lateral position, medical tape can be used to fix the patient in the mid-sagittal plane. The pressure measuring port of the pressure sensor is on the same horizontal line as the mid-sagittal plane, and the pressure monitoring module uses the mid-sagittal plane as the pressure measurement baseline.

[0008] In order to reduce the assembly process of components and improve the level of integration. The preferred technical solution is that the ear canal positioning device, the pressure monitoring module and the three-way connector adopt an integrated combination design. There are many ways of combination integration. Under the premise of satisfying the pressure measurement baseline positioning and measurement accuracy, the design principles of combination integration are high component concentration, small external volume, and convenient and quick installation. Further examples of the combination integration scheme are given, for example: the three-way connector is a hollow cross shape, made of soft medical polymer materials (silicone, soft polyvinyl chloride, etc.), of which the 12 o'clock direction, the 3 o'clock direction and the 6 o'clock direction are connected cavities; the 12 o'clock direction of the three-way connector is provided with an interface connected to the intraventricular drainage catheter, the 3 o'clock direction is provided with an interface connected to the pressure measuring port of the pressure monitoring module, the 6 o'clock direction is provided with an interface connected to the extraventricular drainage catheter, and the 9 o'clock direction is provided with a nipple protrusion that can be inserted into the patient's ear canal for fixation. The nipple protrusion can be prepared in large, medium and small specifications according to different users.

[0009] The pressure monitoring module is mainly composed of a pressure sensor, a matching integrated circuit and a data interface. The pressure sensor range is not less than 0-30cmH2O, and the measurement error is not greater than 1cmH2O. The data interface can be a USB interface or a mini interface. The data interface communicates with drainage monitoring equipment, PC terminals and other monitoring equipment; the drainage monitoring equipment, PC terminals and other monitoring equipment used in conjunction are used to realize the setting of cerebrospinal fluid volume pressure opening thresholds, read out and store patient cerebrospinal fluid volume pressure parameters, drainage volume statistics, and give prompts or warning information. Obviously, with the miniaturization of electronic components, the improvement of functional integration level, and the improvement of electronic patch processing (SMT) equipment and technology, the miniaturization structure of electronic products has become possible. Therefore, the pressure monitoring module can also be integrated with modules including micro communication modules, micro power modules, etc., and used in conjunction with drainage monitoring equipment, PC terminals and other monitoring equipment to achieve wireless communication and collaborative work.

[0010] The head of the extraventricular drainage catheter is connected to the three-way joint, and the tail is connected to the transition joint; the transition joint is used for the connection of the cerebrospinal fluid drainage and collection device used in conjunction with the embodiment of the present disclosure. For example, the transition joint is connected to the drainage pipeline of the downstream cerebrospinal fluid drainage and collection device to guide the cerebrospinal fluid into the container of the cerebrospinal fluid drainage and collection device. The structure and appearance of the spinal fluid drainage and collection device used in conjunction with the embodiment of the present disclosure are not limited, and any liquid collection device that can be matched and connected with the transition joint is acceptable.

[0011] The outer periphery of the extraventricular drainage catheter is provided with a catheter clamp, which is a control device for controlling the opening or closing of the drainage pipeline of cerebrospinal fluid, and the catheter clamp is arranged at the downstream position of the three-way joint. The catheter clamp can adopt structures such as a clip, a needle-mouthed clamp, a cross valve, and a stop valve. When the catheter clamp is closed, the downward drainage of cerebrospinal fluid is blocked, and the cerebrospinal fluid accumulates in the upstream pipeline of the catheter clamp. According to the pressure conduction principle of the fluid, the pressure monitoring module can effectively monitor the dynamic pressure in the drainage catheter and give the cerebrospinal fluid volume pressure in the patient's brain. When the cerebrospinal fluid volume pressure in the patient's brain exceeds the set open drainage threshold, for example, when the set open drainage threshold of 20cmH2O is reached, the pressure monitoring module gives a prompt message, such as a voice prompt or a buzzer prompt, and the medical staff or the accompanying family members open the catheter clamp to open the drainage of cerebrospinal fluid. Each time the drainage fluid reaches about 20ml, the catheter clamp is closed again to prevent bacteria from retrograde upward, and the operation is cyclic. The disclosed embodiment is used in conjunction with a drainage monitoring device having the functions of flow measurement and drainage state control to control the drainage state according to the set open drainage threshold and drainage volume. For example, the medical staff sets the open drainage threshold to 20cmH2O, and the pressure monitoring module sends the acquired dynamic pressure to the drainage monitoring device in real time. When the open drainage threshold is reached, the electronic stop valve of the drainage monitoring device automatically opens, and the drainage monitoring device dynamically monitors the drainage speed and drainage volume. When the set drainage volume is reached, the stop valve closes the pipeline to block the drainage path, and the cycle continues.

[0012] The disclosed embodiment provides a cerebrospinal fluid drainage catheter with a new structure, which is used in conjunction with a cerebrospinal fluid drainage collection device, and can also be used in conjunction with a drainage monitoring device. The beneficial effect of the disclosed embodiment is that an ear canal positioning device is provided on the periphery of the intraventricular drainage catheter, and the ear canal positioning device and the pressure measuring port of the pressure monitoring module are on the same horizontal line as the center of the patient's ear canal, which can accurately locate the pressure measurement baseline of the cerebrospinal fluid volume pressure, effectively solving the positioning problem of the pressure measurement baseline when the personality of different patients or the height of the head of the bed changes, and improving the accuracy of cerebrospinal fluid volume pressure monitoring. At the same time, according to the set cerebrospinal fluid volume pressure threshold, the drainage line is opened to achieve intermittent drainage, block the retrograde upward pathway of bacteria, and improve the safety of cerebrospinal fluid drainage. The technical solution provided by the disclosed embodiment has high medical cost performance, simple operation, high consistency of monitoring data, and important clinical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of an embodiment of the present disclosure.

[0014] Figure 2 It is a structural schematic diagram of Example 1.

[0015] As shown in the figure: an extraventricular drainage catheter (1), a three-way connector (2), a pressure monitoring module (3), a data interface (4), an ear canal positioning device (5), an extraventricular drainage catheter (6), a transition connector (7), a catheter clamp (8), a drainage hole (9), and an extension pipeline (10). DETAILED DESCRIPTION

[0016] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings and examples.

[0017] Example 1: Preparation Figure 2 The embodiment of the integrated structure shown

[0018] In this embodiment, the three components of the three-way connector (2), the pressure monitoring module (3), and the ear canal positioning device (5) are designed as an integrated combination to improve the integration level. The specific preparation process is briefly described as follows:

[0019] 1. If Figure 2 As shown in the structure, an injection mold for a three-way connector (2) is prepared. The three-way connector (2) is provided with a pipeline interface with a diameter of 2 mm and a depth of 6 mm at the 12 o'clock direction; a pressure monitoring module (3) interface with a diameter of 10 mm and a depth of 8 mm is provided at the 3 o'clock direction, and the pressure monitoring module (3) interface should be provided with a data interface (4) position; and a pipeline interface with a diameter of 4 mm and a depth of 6 mm is provided at the 6 o'clock direction. Among them, the 12 o'clock direction, the 3 o'clock direction and the 6 o'clock direction are connected cavities. The ear canal positioning device (5) is located at the 9 o'clock position on the left side of the three-way connector (2), and the external shape is a closed structure with a nipple protrusion. It is completed by injection molding using soft polyvinyl chloride material and is ready for use.

[0020] 2. Prepare a soft polyvinyl chloride extrusion die for the intraventricular drainage catheter (1) and the extraventricular drainage catheter (6), wherein the intraventricular drainage catheter (1) has an outer diameter of 1.9 mm and a wall thickness of 0.4 mm; the extraventricular drainage catheter (6) has an outer diameter of 3.9 mm and a wall thickness of 0.4 mm. Use soft polyvinyl chloride extrusion and slitting to produce the intraventricular drainage catheter (1) with a length of 35 cm and the extraventricular drainage catheter (6) with a length of 15 cm. After production, the catheter is ready for use.

[0021] 3. Use a laser drilling device to prepare six small holes with a diameter of 0.8 mm on the head of the intraventricular drainage catheter (1) for future use.

[0022] 4. Prepare the injection molds of the transition joint (7) and the catheter clamp (8). The catheter clamp (8) is a conventional clamp with a lock buckle. The transition joint (7) is a pagoda-shaped tapered joint. The tail is provided with a pipe internal interface with a diameter of 4 mm and a depth of 6 mm. The head and the tail are connected and are ready for injection molding.

[0023] 5. Prepare the corresponding PCB board, which is round and has a diameter of 9.2 mm. Use the surface mount technology (SMT) to solder the pressure sensor and data interface (4) on the PCB board, with the pressure sensor pressure port located directly above the PCB. After the pressure sensor pressure port is well protected, apply insulating glue on the surface to prepare the pressure monitoring module (3) for later use.

[0024] 6. Product assembly

[0025] (1) Using medical cyclohexanone glue, the tail of the intraventricular drainage catheter (1) is bonded to the 12 o'clock interface of the three-way connector (2), and the extraventricular drainage catheter (6) is bonded to the 6 o'clock interface of the three-way connector (2).

[0026] (2) After the catheter clamp (8) is installed on the periphery of the extraventricular drainage catheter (6), the tail interface of the transition joint (7) is bonded to the tail end of the extraventricular drainage catheter (6) using medical cyclohexanone glue.

[0027] (3) Install the pressure monitoring module (3) into the 3 o'clock position interface of the three-way connector (2), with the pressure measuring port of the pressure monitoring module (3) facing the internal cavity of the three-way connector (2), and the data interface (4) located outside the three-way connector (2). After installation and fixation, use insulating sealant to seal the outer periphery of the pressure monitoring module (3), and check the airtightness between the pressure monitoring module (3) and the outside world. There should be no leakage.

[0028] 7. The prepared product is sterilized and analyzed using ethylene oxide, and passed the sterility test and is ready for use.

[0029] The above-mentioned drawings and embodiments are only used to illustrate the technical solutions of the embodiments of the present disclosure rather than to limit them. Although the embodiments of the present disclosure are described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the embodiments of the present disclosure can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the embodiments of the present disclosure, which should be included in the scope of the claims of the embodiments of the present disclosure and do not constitute any limitation on the protection scope of the embodiments of the present disclosure.

Claims

1. A cerebrospinal fluid drainage pipeline capable of accurate pressure measurement and intermittent drainage control, mainly comprising an intraventricular drainage catheter (1), a three-way connector (2), an extraventricular drainage catheter (6), an ear canal positioning device (5), a pressure monitoring module (3), a transition joint (7) and a catheter clamp (8), characterized in that: The three-way connector (2) is used for connecting and connecting the three components of the intraventricular drainage catheter (1), the extraventricular drainage catheter (6) and the pressure monitoring module (3); the head of the intraventricular drainage catheter (1) is provided with a drainage hole (9); the upstream interface of the three-way connector (2) is connected to the tail of the intraventricular drainage catheter (1); the downstream interface of the three-way connector (2) is connected to the head of the extraventricular drainage catheter (6); and the other interface of the three-way connector (2) is connected to the pressure measuring port of the pressure monitoring module (3); the outer periphery of the rear end of the intraventricular drainage catheter (1) is provided with an ear canal positioning device (5); the ear canal positioning device (5) and the pressure monitoring module (3) are arranged on the same horizontal line, or after the ear canal positioning device (5) is fixed on the patient's head, the pressure measuring port of the pressure monitoring module (3) and the center of the patient's ear canal are on the same horizontal line; The ear canal positioning device, the pressure monitoring module and the three-way connector are designed as an integrated combination; depending on the patient's body position or the puncture and drainage site, the ear canal positioning device (5) can also be positioned at other locations on the patient's head for pressure measurement.

2. A cerebrospinal fluid drainage circuit capable of accurate pressure measurement and intermittent drainage control according to claim 1, characterized in that: An extension catheter (10) is provided between the three-way connector (2) and the pressure measuring port of the pressure monitoring module (3); the extension catheter (10) physically isolates the drained cerebrospinal fluid from the pressure measuring port of the pressure monitoring module (3).

3. A cerebrospinal fluid drainage circuit capable of accurate pressure measurement and intermittent drainage control according to claim 1, characterized in that: The three-way connector (2) is in the shape of a hollow cross and is made of a soft medical polymer material, wherein the three points at the 12 o'clock direction, the 3 o'clock direction and the 6 o'clock direction are connected cavities; the three-way connector (2) is provided with an interface connected to the intraventricular drainage catheter (1) at the 12 o'clock direction, an interface connected to the pressure measuring port of the pressure monitoring module (3) at the 3 o'clock direction, an interface connected to the extraventricular drainage catheter (6) at the 6 o'clock direction, and a nipple protrusion that can be inserted into the patient's ear canal for fixation at the 9 o'clock direction.

4. A cerebrospinal fluid drainage circuit capable of accurate pressure measurement and intermittent drainage control according to claim 1, characterized in that: A catheter clamp (8) is provided on the outer periphery of the extraventricular drainage catheter (6), and the catheter clamp (8) is arranged at a downstream position of the three-way connector (2).

5. A cerebrospinal fluid drainage pipeline capable of accurate pressure measurement and intermittent drainage control according to claim 1, characterized in that: When used in conjunction with drainage monitoring equipment that has the functions of flow measurement and drainage status control, the drainage status can be controlled according to the set open drainage threshold and drainage volume.

6. A cerebrospinal fluid drainage circuit capable of accurate pressure measurement and intermittent drainage control according to claim 1, characterized in that: The pressure monitoring module (3) is mainly composed of a pressure sensor, a matching integrated circuit and a data interface (4).

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