A central venous catheter capable of accurate temperature measurement and a preparation method thereof

Abstract

The application relates to the technical field of medical devices, and provides a central venous catheter capable of accurately measuring temperature and a preparation method thereof.The central venous catheter comprises a main body pipe, an infusion channel and a temperature measuring channel are arranged in the main body pipe, the infusion channel is connected with an extension pipe, a temperature sensor is arranged in the temperature measuring channel, the temperature sensor is connected with a temperature measuring lead wire, a temperature measuring groove in communication with the outside is formed in the temperature measuring channel, a heat insulation layer is arranged on the inner wall of the temperature measuring channel close to the infusion channel, a heat conduction layer for sealing the temperature measuring groove is arranged on the inner wall of the temperature measuring channel away from the infusion channel, and the heat conduction layer and the heat insulation layer completely wrap the temperature sensor; the heat insulation film on the lower surface of the temperature sensor can realize relative sealing space between the temperature measuring channel and the medicine channel, the heat conduction gel on the upper surface of the temperature sensor is in contact with the outside through the temperature measuring groove opening, the accuracy, response speed and influence of infusion liquid on temperature of data are guaranteed, and the occurrence of medical risk accidents is reduced.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a central venous catheter capable of accurate temperature measurement and its preparation method. Background Technology

[0002] A central venous catheter, a type of vascular catheter, is a medical consumable used to establish a reliable long-term indwelling channel within the body for intraoperative or postoperative intravenous fluid and blood transfusion, intravenous nutrition therapy, and monitoring of venous pressure and temperature. During and after surgery, in order to better monitor the patient's vital signs, it is necessary to monitor the patient's central venous blood temperature to facilitate real-time clinical assessment of changes in the patient's body temperature. Therefore, existing central venous catheters are usually equipped with temperature sensors to perform blood temperature monitoring.

[0003] In existing central venous catheters with blood temperature monitoring, the temperature sensor is usually located inside the catheter, separated from the blood by a polyurethane wall. Polyurethane has a low thermal conductivity, typically between 0.018 and 0.024 W / (m·K). During clinical fluid infusion, the fluid temperature is conducted to the temperature sensor through the tube wall, leading to temperature measurement deviations. Furthermore, since the temperature sensor is placed inside the lumen, air inevitably exists between it and the tube wall, affecting the temperature response speed. For these reasons, the temperature measured by the temperature sensor deviates significantly from the actual blood temperature and cannot fully and accurately reflect the real temperature. Moreover, the slow temperature response during measurement may lead to inaccurate clinical judgment. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to address the shortcomings of the prior art by providing a central venous catheter capable of accurate temperature measurement and its preparation method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A central venous catheter capable of accurate temperature measurement includes a main tube, within which a temperature measurement channel and an infusion channel are provided. A temperature sensor is installed in the temperature measurement channel and connected to a temperature measurement lead wire. The temperature measurement channel has a temperature measurement groove communicating with the outside environment. A heat insulation layer is provided on the inner wall of the temperature measurement channel near the infusion channel, and a heat-conducting layer is provided on the inner wall of the temperature measurement channel away from the infusion channel to seal the temperature measurement groove. The heat-conducting layer and the heat insulation layer completely enclose the temperature sensor. The infusion channel is connected to an extension tube.

[0006] As a further improvement of the present invention, the heat insulation layer is a heat insulation film, and the heat conduction layer is a heat conduction gel filling layer. After the heat conduction gel filling layer and the heat insulation film are sealed and bonded together, the temperature sensor is completely wrapped.

[0007] As a further improvement of the present invention, the area of ​​the upper layer of the heat-conducting layer is larger than the opening area of ​​the temperature measuring groove, the area of ​​the lower layer of the heat-conducting layer is larger than the area of ​​the temperature sensor, the area of ​​the heat insulation layer is larger than the area of ​​the lower layer of the heat-conducting layer, and the opening area of ​​the temperature measuring groove is larger than the area of ​​the temperature sensor.

[0008] As a further improvement of the present invention, the heat insulation layer is a sealed cylindrical structure that fits into the inner wall of the temperature measuring channel, and the cylindrical structure has a temperature measuring port with the same shape as the opening of the temperature measuring groove on its side.

[0009] As a further improvement of the present invention, the heat insulation film is an aerogel heat insulation film material, and the thermally conductive gel filling layer is an organosilicon resin thermally conductive material.

[0010] As a further improvement of the present invention, a tube body connector is provided at one end of the main tube, the temperature measuring wire in the temperature measuring channel passes through the tube body connector, the end of the temperature measuring wire is connected to a data transmission module, and the infusion channel is connected to the extension tube through the tube body connector.

[0011] As a further improvement of the present invention, the extension tube is provided with a flow stop clamp, and the end of the extension tube is connected to an injection connector.

[0012] A method for preparing a central venous catheter capable of accurate temperature measurement, characterized by comprising the following process steps: S1: Main tube extrusion process: The main tube is extruded using a mature extruder; S2: Advanced manufacturing process, using advanced equipment to combine the main tube with the soft tip tube by heating and melting; S3: Temperature measuring groove processing technology: A temperature measuring groove is opened near the tip by drilling holes; S4: Insulation layer preparation process: The insulation film is placed in the temperature measuring channel and fixed at the corresponding position of the temperature measuring groove on the inner wall of the temperature measuring channel near the infusion channel; S5: Temperature sensor insertion process: First, the temperature measuring wire connected to the temperature sensor is inserted into the temperature measuring channel through the temperature measuring tank, and then the temperature sensor is inserted and fixed on the upper surface of the heat insulation film. S6: Thermal conductive layer preparation process: Using a glue filling device, glue is injected through a temperature measuring tank to form a thermal conductive gel filling layer; S7: Curing process: According to the characteristics of thermal conductive gel, allow it to stand to allow the thermal conductive gel filling layer to fully cure; S8: Cleaning process: After curing, check and clean the temperature measuring tank area, remove excess thermal conductive gel, and polish the temperature measuring tank area to make it smooth without protruding burrs. S9: Injection molding process: The injection channel inside the main tube is connected to the extension tube through injection molding of the connector, and the temperature measuring wire is fixed in the temperature measuring channel.

[0013] As a further improvement of the present invention, physical vapor deposition process can also be used in process step S4, and a heat insulation film can be deposited on the inner wall of the temperature measuring channel by low temperature physical vapor deposition technology.

[0014] As a further improvement of the present invention, the glue dispensing amount in process step S6 is 2mm. 3 -8mm 3 The glue dispensing speed is 0.2mm. 3 / s-0.8mm 3 / s, ensuring that the thermally conductive gel completely covers the temperature sensor, fills the tube wall, and prevents the formation of air bubbles.

[0015] The beneficial effects of this invention are: 1. This invention provides a central venous catheter capable of accurate temperature measurement. The temperature sensor is completely encased by a thermally conductive gel layer and an insulating film layer, which are sealed together. The insulating film on the lower surface of the temperature sensor creates a relatively closed space between the temperature measurement channel and the drug delivery channel. During infusion, the temperatures of the two channels remain relatively stable and unaffected by each other, improving the accuracy of the temperature sensor readings. The thermally conductive gel on the upper surface of the temperature sensor contacts the outside environment through the opening in the temperature measurement slot. The thermal conductivity of the gel is much higher than that of TPU material, exhibiting highly efficient heat conduction performance. It can quickly respond to temperature changes, ensuring consistency between blood temperature and sensor temperature, thereby reducing the difference between the measured and actual temperatures. The combination of the thermally conductive gel layer and the insulating film layer ensures data accuracy, response speed, and reduces the influence of the infusion fluid on temperature, providing crucial medical judgment information for clinical treatment, improving scientific treatment methods, and reducing the occurrence of medical risks and accidents.

[0016] 2. In this invention, the thermal conductive layer is filled with a thermally conductive gel, which not only has high thermal conductivity but also excellent plasticity, softness, and adhesion. During the preparation and processing of the central venous catheter, the thermal conductive layer is prepared by filling the temperature measuring channel with gel through a temperature measuring tank. By setting an appropriate gel dispensing speed and amount, it can be ensured that the thermally conductive gel completely covers the temperature sensor, fills the tube wall, and does not generate air bubbles. This easily fills uneven interfaces, forms a uniform thermal conductive layer, and simultaneously completes the sealing, bonding, and positioning of the temperature sensor. The preparation process is simple and the thermal conductivity is stable.

[0017] 3. In this invention, the heat insulation film of the heat insulation layer can be a cylindrical structure that matches the inner wall of the temperature measuring channel, thereby wrapping the temperature sensor on three sides. The diameter of the cylinder is the same as the diameter of the inner wall of the temperature measuring channel of the conduit. A temperature measuring port with the same shape as the opening of the temperature measuring groove is opened on the side to facilitate the filling operation. This cylindrical structure can facilitate the insertion and positioning of the heat insulation layer into the conduit while ensuring the heat insulation effect. The preparation process is simple and the heat insulation performance is stable.

[0018] 4. In this invention, a temperature measuring groove structure is provided on the main tube to facilitate the contact of the heat-conducting layer with the blood, thereby directly transferring the blood temperature to the temperature sensor, reducing temperature loss, and ensuring the accuracy and response speed of the test results. When processing central venous catheters, the temperature measuring groove can be used for the insertion of temperature measuring wires and temperature sensors, and can also serve as a glue injection port to form a thermally conductive gel filling layer, simplifying the processing technology and reducing processing costs and processing cycle. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Appendix Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Appendix Figure 2 This is a schematic diagram of a partial structure at the front end of the main tube of the present invention.

[0022] Appendix Figure 3 For the appendix Figure 2 Structural cross-section.

[0023] Appendix Figure 4 This is a schematic diagram of the internal structure of the front end of the main tube of the sealed cylindrical heat insulation layer selected in this invention.

[0024] Appendix Figure 5 For the appendix Figure 4 Cross-sectional view of the front end of the main tube of the selected sealed cylindrical insulation layer.

[0025] Appendix Figure 6 This is a temperature comparison test chart under constant temperature conditions according to the present invention.

[0026] In the diagram: 1 is the main tube, 101 is the temperature measuring channel, 102 is the temperature measuring tank, 103 is the infusion channel, 2 is the temperature sensor, 3 is the insulation layer, 4 is the heat-conducting layer, 5 is the tube body connector, 6 is the temperature measuring wire, 7 is the data transmission module, 8 is the extension tube, 9 is the stop clamp, and 10 is the infusion connector. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0028] like Figure 1 As shown, a central venous catheter capable of accurate temperature measurement includes a main tube 1. The main tube 1 contains a temperature measurement channel 101 and an infusion channel 103. A temperature sensor 2 is installed in the temperature measurement channel 101 and connected to a temperature measurement lead 6. The temperature measurement channel 101 has a temperature measurement groove 102 communicating with the outside. A heat insulation layer 3 is provided on the inner wall of the temperature measurement channel 101 near the infusion channel 103, and a heat-conducting layer 4 is provided on the inner wall of the temperature measurement channel 101 away from the infusion channel 103 to seal the temperature measurement groove 102. The heat-conducting layer 4 and the heat insulation layer 3 completely enclose the temperature sensor 2. The infusion channel 103 is connected to an extension tube 8.

[0029] Preferably, the temperature sensor 2 is a thermistor semiconductor material, which has the advantages of small size and fast response to temperature changes. Its size is 1mm×1mm×0.2mm to 3mm×2mm×0.2mm, the measurement accuracy can reach 0.1℃, and the measurement range is 20℃-50℃.

[0030] In one specific embodiment, the heat insulation layer 3 is a heat insulation film, and the heat conduction layer 4 is a heat conduction gel filling layer. After the heat conduction gel filling layer is sealed and bonded to the heat insulation film, it completely encloses the temperature sensor 2.

[0031] In one specific embodiment, the upper area of ​​the heat-conducting layer 4 is larger than the opening area of ​​the temperature measuring groove 102 to ensure that the filler completely covers the opening of the temperature measuring groove 102 and blood will not flow in; the lower area of ​​the heat-conducting layer 4 is larger than the area of ​​the temperature sensor 2 to completely wrap the temperature sensor 2; the area of ​​the heat insulation layer 3 is larger than the lower area of ​​the heat-conducting layer 4 to ensure that the temperature sensor 2, the heat-conducting layer 4 and the pipe wall are isolated; the opening area of ​​the temperature measuring groove 102 is larger than the area of ​​the temperature sensor 2 to facilitate the insertion and installation of the temperature sensor 2.

[0032] In a specific embodiment, the heat insulation layer 3 is further a sealed cylindrical structure that cooperates with the inner wall of the temperature measuring channel 101, thereby completely isolating the temperature influence of the infusion channel 103 on the temperature measuring channel 101; the cylindrical structure has a temperature measuring port with the same shape as the opening of the temperature measuring groove 102 on its side.

[0033] In a specific embodiment, the insulating film is further described as an aerogel insulating film material, such as silicon (Si) based, carbon (C) based, polyurethane (PU) aerogel, etc., but not limited to these types. It has a good effect of isolating heat conduction. Using an insulating film material here can achieve a relatively closed space between the temperature measuring channel 101 and the infusion channel 103. During infusion, the temperatures of the temperature measuring channel 101 and the infusion channel 103 are relatively stable and do not affect each other, thus improving the accuracy of the temperature sensor 2 test. The thermally conductive gel filling layer is an organosilicon resin thermally conductive material with a thermal conductivity much higher than that of conventional TPU materials. It has efficient thermal conduction performance, can quickly respond to temperature changes, ensure the consistency between blood temperature and temperature sensor 2 temperature, and has excellent plasticity, softness, and adhesion. It can easily fill uneven interfaces to form a uniform thermally conductive layer 4.

[0034] In a specific embodiment, the main tube 1 is further provided with a tube body connector 5 at one end, the temperature measuring wire 6 in the temperature measuring channel 101 passes through the tube body connector 5, the end of the temperature measuring wire 6 is connected to a data transmission module 7, and the infusion channel 103 is connected to the extension tube 8 through the tube body connector 5.

[0035] Preferably, the data transmission module 7 includes a data processing chip to amplify, filter, demodulate, and convert the collected data, and includes a Bluetooth transmitter to transmit the data to an external terminal device.

[0036] Preferably, the end of the temperature measuring wire 6 can be directly connected to an external terminal device.

[0037] In one specific embodiment, the extension tube 8 is further provided with a flow stop clamp 9, and the end of the extension tube 8 is connected to an infusion connector 10, which is used to connect to an external infusion set.

[0038] A method for preparing a central venous catheter capable of accurate temperature measurement, characterized by comprising the following process steps: S1: Main tube 1 extrusion process: Use a mature extruder to extrude the main tube 1; S2: Advanced manufacturing process, using advanced equipment to combine the main tube 1 with the soft tip tube by heating and melting; S3: Processing technology of temperature measuring groove 102: Temperature measuring groove 102 is opened near the tip by drilling; S4: Preparation process of heat insulation layer 3: The heat insulation film is placed into the temperature measuring channel 101 from the opening end of the temperature measuring channel 101 and fixed at the corresponding position of the temperature measuring groove 102 on the inner wall of the temperature measuring channel 101 near the infusion channel 103. S5: Temperature sensor 2 insertion process: First, the temperature measuring wire 6 connected to the temperature sensor 2 is inserted into the temperature measuring channel 101 through the temperature measuring tank 102, and then the temperature sensor 2 is inserted and fixed on the upper surface of the heat insulation film. S6: Thermal conductive layer 4 preparation process: Using a glue filling device, glue is injected through the temperature measuring tank 102 to form a thermal conductive gel filling layer; S7: Curing process: According to the characteristics of thermal conductive gel, allow it to stand to allow the thermal conductive gel filling layer to fully cure; S8: Cleaning process: After curing, inspect and clean the temperature measuring tank 102, remove excess thermal conductive gel, and polish the temperature measuring tank 102 to make it smooth without protruding burrs. S9: Injection molding process: The injection channel 103 in the main tube 1 is connected to the extension tube 8 by injection molding through the connector, and the temperature measuring wire 6 is fixed in the temperature measuring channel 101.

[0039] Preferably, in process step S1, the main tube 1 may include double-lumen, triple-lumen, quadruple-lumen, etc., with a lumen size of 4Fr-8.5Fr, and different specifications may have different lumen lengths of 8cm-30cm.

[0040] Preferably, in process step S2, some of the tip process parameters are shown in Table 2 below.

[0041] Table 2: Advanced Process Parameters model Temperature (°C) Pressure (psi) Clamp (s) Promote(s) Delay (s) Heating (s) Cooling (s) 2-6Fr 118±10 13±4 10±1 10±1 4±0.5 8±1 9±1 2-7Fr 118±10 14±4 10±1 10±1 4±0.5 8±1 9±1 2-8Fr 122±10 15±4 11±1 11±1 4±0.5 9±1 10±1 3-4Fr 112±10 10±4 12±1 11±1 4±0.5 8±1 9±1 3-7Fr 122±10 16±4 13±1 12±1 4±0.5 8±1 9±1 3-8.5Fr 122±10 15±4 13±1 12±1 4±0.5 9±1 10±1 Preferably, in process step S3, the temperature measuring groove 102 can be processed with reference to existing mature drilling technology, and a temperature measuring groove with a diameter of 1mm-3mm can be opened 1mm-2mm away from the tip.

[0042] Preferably, in process step S4, the lower surface of the heat insulation film is coated with quick-drying adhesive, and after being placed in the heat insulation film, it is left to stand for 5-10 minutes to quickly fix the heat insulation film to the inner wall of the temperature measuring channel.

[0043] Preferably, in process step S5, the back of the temperature sensor 2 is provided with an adhesive layer for fixing it to the heat insulation film.

[0044] Preferably, in process step S7, the thermally conductive gel filling layer is left to stand for 30 min-120 min to allow it to fully solidify.

[0045] In a specific embodiment, further, physical vapor deposition process can be selected in process step S4 to deposit an insulating film on the inner wall of the temperature measuring channel 101 through low-temperature physical vapor deposition technology.

[0046] Preferably, the physical vapor deposition process can be a low-temperature magnetron sputtering process, and the insulating film can be a nanoporous silica aerogel film.

[0047] In one specific embodiment, further, the glue dispensing amount in process step S6 is 2mm. 3 -8mm 3 The glue dispensing speed is 0.2mm. 3 / s-0.8mm 3 / s, ensuring that the thermally conductive gel completely covers the temperature sensor 2, fills the tube wall, and does not generate bubbles.

[0048] A comparison was made between a commercially available temperature-measuring central venous catheter (Catheter A) and the patented temperature-measuring central venous catheter (Catheter B). Testing was conducted by connecting to a constant-temperature heat source. Three heat sources were selected: 30℃, 37℃, and 45℃. Data was collected for each heat source corresponding to both Catheter A and Catheter B for comparison. Data was collected every 10 seconds. From 0s to 100s, no fluid was infused; from 100s to 200s, room-temperature fluid was infused; and from 200s to 300s, infusion was stopped. The test results are attached. Figure 6 As shown.

[0049] Analysis Appendix Figure 6 The test data shows that: Under constant temperature conditions of 30℃, the average measured temperature of catheter A was 28.8℃, and the average measured temperature of catheter B was 29.6℃. The actual temperature of catheter B was 0.8℃ higher than that of catheter A, and was closer to the heat source temperature, making the measurement more accurate. At the beginning of the temperature test, the temperature of catheter A showed a more obvious upward trend in the 0s-30s interval, indicating that the temperature response speed of catheter A was slower. During fluid infusion, both catheters A and B showed a downward trend in temperature. The temperature of catheter A decreased more significantly, indicating that it was more affected by the temperature of the infused fluid, while the temperature of catheter B decreased less, indicating that it was less affected by the infusion.

[0050] Under constant temperature conditions of 37℃, the average measured temperature of catheter A was 36.3℃, and the average measured temperature of catheter B was 36.8℃. The actual temperature of catheter B was 0.5℃ higher than that of catheter A, and was closer to the heat source temperature, making the measurement more accurate. At the beginning of the temperature test, the temperature of catheter A showed a more obvious upward trend in the 0s-30s interval, indicating that the temperature response speed of catheter A was slower. During fluid infusion, both catheters A and B showed a downward trend in temperature. The temperature of catheter A decreased more significantly, indicating that it was more affected by the temperature of the infused fluid, while the temperature of catheter B decreased less, indicating that it was less affected by the infusion.

[0051] Under constant temperature conditions of 45℃, the average measured temperature of catheter A was 44.1℃, and the average measured temperature of catheter B was 44.7℃. The actual temperature of catheter B was 0.6℃ higher than that of catheter A, and was closer to the heat source temperature, making the measurement more accurate. At the beginning of the temperature test, the temperature of catheter A showed a more obvious upward trend in the 0s-30s interval, indicating that the temperature response speed of catheter A was slower. During fluid infusion, both catheters A and B showed a downward trend in temperature. The temperature of catheter A decreased more significantly, indicating that it was more affected by the temperature of the infused fluid, while the temperature of catheter B decreased less, indicating that it was less affected by the infusion.

[0052] Comparing catheters A and B based on the above conclusions, catheter B of this patent showed consistent test results under constant temperature conditions of 30℃, 37℃, and 45℃, with a temperature tolerance of 0.3℃. The average test data was closer to the standard temperature, and the catheter responded quickly to temperature changes, better meeting the requirements for clinical use. Furthermore, it was less affected by the infused fluid after infusion. Therefore, the product involved in this patent has more accurate temperature testing, faster response, and less impact from the infused fluid.

[0053] It is understood that the above specific description of the present invention is only for illustrating the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention to achieve the same technical effect; as long as the use needs are met, they are all within the protection scope of the present invention.

[0054] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A central venous catheter capable of accurate temperature measurement, comprising a main body tube (1), a temperature measurement channel (101) and an infusion channel (103) are arranged in the main body tube (1), a temperature sensor (2) is installed in the temperature measurement channel (101), the temperature sensor (2) is connected with a temperature measurement lead wire (6), characterized in that, The temperature measuring channel (101) is provided with a temperature measuring groove (102) that is connected to the outside. The inner wall of the temperature measuring channel (101) near the infusion channel (103) is provided with a heat insulation layer (3). The inner wall of the temperature measuring channel (101) away from the infusion channel (103) is provided with a heat-conducting layer (4) that seals the temperature measuring groove (102). The heat-conducting layer (4) and the heat insulation layer (3) completely wrap the temperature sensor (2). The infusion channel (103) is connected to the extension tube (8).

2. The accurate temperature measuring central venous catheter according to claim 1, characterized in that, The heat insulation layer (3) is a heat insulation film, and the heat conduction layer (4) is a heat conduction gel filling layer. After the heat conduction gel filling layer is sealed and bonded to the heat insulation film, it completely wraps the temperature sensor (2).

3. The accurate temperature measuring central venous catheter according to claim 2, characterized in that, The upper area of ​​the heat-conducting layer (4) is larger than the opening area of ​​the temperature measuring groove (102), the lower area of ​​the heat-conducting layer (4) is larger than the area of ​​the temperature sensor (2), the area of ​​the heat insulation layer (3) is larger than the lower area of ​​the heat-conducting layer (4), and the opening area of ​​the temperature measuring groove (102) is larger than the area of ​​the temperature sensor (2).

4. The accurate temperature measuring central venous catheter according to claim 2, characterized in that, The heat insulation layer (3) is a sealed cylindrical structure that fits into the inner wall of the temperature measuring channel (101). The cylindrical structure has a temperature measuring port on its side that has the same shape as the opening of the temperature measuring groove (102).

5. The thermometrically accurate central venous catheter of claim 2, wherein, The thermal insulation film is an aerogel thermal insulation film material, and the thermally conductive gel filling layer is an organosilicon resin thermally conductive material.

6. The thermometrically accurate central venous catheter of claim 2, wherein, One end of the main tube (1) is provided with a tube body connector (5), the temperature measuring wire (6) in the temperature measuring channel (101) passes through the tube body connector (5), the end of the temperature measuring wire (6) is connected to a data transmission module (7), and the infusion channel (103) is connected to the extension tube (8) through the tube body connector (5).

7. The thermometrically accurate central venous catheter of claim 2, wherein, The extension tube (8) is provided with a flow stop clamp (9), and the end of the extension tube (8) is connected to an injection connector (10).

8. A method of manufacturing the central venous catheter capable of accurate temperature measurement according to any one of claims 2 to 7, characterized in that, The process includes the following steps: S1: Extrusion process of main tube (1): Use a mature extruder to extrude the main tube (1); S2: Advanced manufacturing process, using advanced equipment, to combine the main tube (1) with the soft-tip tip tube by heating and melting; S3: Temperature measuring groove (102) processing technology: A temperature measuring groove (102) is opened near the tip by drilling. S4: Preparation process of heat insulation layer (3): The heat insulation film is placed in the temperature measuring channel (101) and fixed at the corresponding position of the temperature measuring groove (102) on the inner wall of the temperature measuring channel (101) near the infusion channel (103); S5: Temperature sensor (2) insertion process: First, the temperature measuring wire (6) connected to the temperature sensor (2) is inserted into the temperature measuring channel (101) through the temperature measuring tank (102), and then the temperature sensor (2) is inserted and fixed on the upper surface of the heat insulation film. S6: Thermal conductive layer (4) preparation process: Using a glue filling device, glue is injected through a temperature measuring tank (102) to form a thermal conductive gel filling layer; S7: Curing process: According to the characteristics of thermal conductive gel, allow it to stand to allow the thermal conductive gel filling layer to fully cure; S8: Cleaning process: After curing, check and clean the temperature measuring tank (102) to remove excess thermal conductive gel and polish the temperature measuring tank (102) to make it smooth and free of protruding burrs. S9: Injection molding process: The injection channel (103) in the main tube (1) is connected to the extension tube (8) by injection molding of the connector, and the temperature measuring wire (6) is fixed in the temperature measuring channel (101).

9. The method of claim 8, wherein the temperature-accurately-measurable central venous catheter is prepared by In the process step S4, physical vapor deposition can also be used to coat the inner wall of the temperature measuring channel (101) with a heat insulation film by low temperature physical vapor deposition technology.

10. The method of claim 8, wherein the temperature-accurately-measurable central venous catheter is prepared by the steps of: The glue injection amount in the process step S6 is 2mm 3 -8mm 3 , the glue injection speed is 0.2mm 3 / s-0.8mm 3 / s, which ensures that the heat-conducting gel completely covers the temperature sensor (2), fills the pipe wall and has no air bubbles.

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