A collection device for assisting in monitoring end-tidal carbon dioxide

Abstract

This invention relates to a collection device for assisting in the monitoring of end-tidal carbon dioxide, comprising: a horizontal tube for connection to a patient's breathing circuit; a dual-lumen sampling tube including a transition cavity connected to the horizontal tube, and a gas sampling tube and a liquid sampling tube connected to the transition cavity, the gas sampling tube being located above the liquid sampling tube; and a gas-liquid separator connecting the gas sampling tube and the liquid sampling tube. Compared with the prior art, this invention can solve problems such as interference from water vapor and condensate, and blockage, providing high-quality auxiliary monitoring for clinical use and improving the accuracy of diagnosis and treatment.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology and relates to a collection device for assisting in the monitoring of carbon dioxide at the end of the respiratory tract. Background Technology

[0002] End-tidal carbon dioxide (etCO2) monitoring technology has been widely used globally, particularly in intensive care, anesthesia, emergency medicine, and respiratory therapy. This monitoring technology began to be used in clinical practice around the 1980s, and its application has continued to expand with improvements in monitoring equipment and in-depth clinical research. This non-invasive and safe technology continuously monitors the partial pressure or concentration of carbon dioxide in the exhaled breath of ordinary patients or patients with artificial airways, visually displaying a carbon dioxide curve, which helps in judging and predicting changes and developments in various clinical procedures and the patient's condition.

[0003] There are three methods for measuring end-tidal carbon dioxide: infrared method, mass spectrometry method, and colorimetric method. The commonly used infrared method in clinical practice is further divided into two types according to the gas sampling method: side-flow type and main-flow type. The side-flow type involves continuously and quantitatively collecting gas from the breathing circuit of the patient with an artificial airway; while the main-flow type is directly connected to the breathing circuit without the need for additional sample collection.

[0004] The two existing technologies mentioned above have the following drawbacks:

[0005] 1. Measurement error: In actual clinical use, it has been found that the collected exhaled air contains other components such as water vapor, condensate, and secretions, which may cause blockage of the collector sampling tube and tube opening, resulting in measurement error of the CO2 sensor (the CO2 curve is inconsistent with the actual situation) or even failure to display data. Medical staff will find it difficult to accurately analyze the patient's breathing and airway status, thus affecting the accuracy of diagnosis and treatment.

[0006] 2. Consumable costs: High-quality CO2 monitoring equipment and consumables have relatively high costs. They are generally used by one person only. However, it is difficult to avoid the presence of other components such as water vapor, condensation, and secretions in exhaled air, which increases the consumption rate of consumables. This may affect the adoption by medical institutions.

[0007] 3. Maintenance and cleaning of consumables: CO2 detectors and gas collection devices require regular maintenance and calibration to ensure accuracy and reliability; healthcare personnel need to check, clean, or replace consumables in the connecting tubes and CO2 collectors more frequently to prevent blockage and contamination problems.

[0008] 4. Additional time costs: Dealing with blockages and clearing problems may take extra time, which could affect the workflow of healthcare workers and the treatment of critically ill patients.

[0009] 5. Labor costs: The labor costs for ensuring the normal operation and maintenance of equipment may increase. Summary of the Invention

[0010] The purpose of this invention is to provide a collection device for assisting in the monitoring of carbon dioxide at the end of the respiratory tract, which can solve problems such as interference from water vapor and condensate and blockage, providing high-quality auxiliary monitoring for clinical use and improving the accuracy of diagnosis and treatment.

[0011] The objective of this invention can be achieved through the following technical solutions:

[0012] A collection device for assisting in monitoring end-tidal carbon dioxide, comprising:

[0013] Used to connect to the horizontal tube in the patient's breathing circuit;

[0014] A dual-cavity sampling tube includes a transition cavity connected to the horizontal tube, and a gas sampling tube and a liquid sampling tube connected to the transition cavity, wherein the gas sampling tube is located above the liquid sampling tube;

[0015] And a gas-liquid separator connecting the gas sampling tube and the liquid sampling tube.

[0016] Furthermore, the horizontal tube is provided with an air inlet that connects to the transition cavity, and a microporous filter membrane covering the air inlet is arranged inside the horizontal tube.

[0017] Furthermore, the area of ​​the transition cavity near the gas sampling tube and the liquid sampling tube is funnel-shaped with a gradually increasing inner diameter.

[0018] Furthermore, the middle and rear section of the transition cavity is also provided with a hydrophobic plate, and there is a gap between the end of the hydrophobic plate and the gas sampling tube.

[0019] Furthermore, the gas sampling tube and the liquid sampling tube are provided with an interconnected intermediate channel in the middle region.

[0020] Furthermore, the intermediate channel is also equipped with a one-way valve that can only be opened toward the liquid sampling tube.

[0021] Furthermore, the gas-liquid separator is also provided with a partition plate, which divides the gas-liquid separator into a gas cavity located above and a liquid cavity located below. The gas cavity is connected to the gas sampling tube, and the liquid cavity is connected to the liquid sampling tube. The partition plate is provided with a vent hole.

[0022] Furthermore, the partition plate is also provided with a waterproof and breathable membrane covering the breathable pores.

[0023] Furthermore, the partition plate includes a plate edge region that connects with the inner wall of the gas-liquid separator, and a plate middle body that is connected to and integrally formed with the plate edge region. The height of the plate middle body is not lower than that of the plate edge region, so that a liquid collection trough with an upper opening is formed between the plate edge region and the inner wall of the gas-liquid separator.

[0024] Furthermore, the gas cavity is also equipped with an interface on the separator tank for connecting to an external end-tidal carbon dioxide monitoring module.

[0025] Furthermore, the bottom of the liquid cavity is also provided with a lower interface of the separator tank, and a liquid collection filter and a drain valve are sequentially installed at the lower interface of the separator tank.

[0026] Monitoring the partial pressure or concentration of carbon dioxide in the end-tidal gas helps in judging and predicting changes and developments in various clinical procedures and patient conditions, which is of great clinical significance. However, problems frequently arise, such as blockage of the exhaled gas collection tubing by exhaled water vapor, condensation, and collector inlet, leading to measurement errors or even failure to display data. Therefore, this invention provides a dual-lumen tubing collection device with gas-liquid separation function. Utilizing the negative pressure difference provided by an existing end-tidal carbon dioxide monitoring module connected to it, it collects exhaled gas and the measurement gas through dual channels, achieving accurate monitoring of exhaled CO2 concentration, solving problems such as water vapor, condensation interference, and blockage, providing high-quality auxiliary monitoring for clinical use, and improving the accuracy of diagnosis and treatment. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention;

[0028] Explanation of markings in the diagram:

[0029] 1-Dual-lumen sampling tube, 11-Gas sampling tube, 12-Liquid sampling tube, 13-One-way valve, 14-Hydrophobic plate, 15-Transition cavity, 16-Intermediate channel;

[0030] 2-Horizontal and vertical pipes;

[0031] 3-Gas-liquid separator, 31-Gas cavity, 32-Liquid cavity, 33-Divider plate, 34-Liquid collection filter, 35-Water drain valve, 36-Liquid collection tank. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0033] In the following embodiments, unless otherwise specified, the functional components or structures are conventional components or structures used in the art to achieve the corresponding functions.

[0034] To address issues such as interference and blockage from water vapor and condensate, and to provide high-quality auxiliary monitoring for clinical use, thereby improving the accuracy of diagnosis and treatment, this invention provides a collection device for auxiliary monitoring of end-tidal carbon dioxide. Its structure can be found in [reference needed]. Figure 1 As shown, it includes:

[0035] 2, used to connect to the patient's breathing circuit;

[0036] The dual-cavity sampling tube 1 includes a transition cavity 15 connected to the horizontal tube 2, and a gas sampling tube 11 and a liquid sampling tube 12 connected to the transition cavity 15. The gas sampling tube 11 is located above the liquid sampling tube 12. In actual operation, water vapor and other substances in the gas will partially condense in the transition cavity 15. Based on the difference in gravity between water and gas, under the negative pressure generated by the external monitoring module, water vapor and some condensed droplets are mainly drawn from the liquid sampling tube 12 into the gas-liquid separator 3, while the gas with separated water vapor is mainly drawn from the gas sampling tube 11 into the gas-liquid separator 3.

[0037] And a gas-liquid separator 3 that connects the gas sampling tube 11 and the liquid sampling tube 12.

[0038] In some specific embodiments, the horizontal tube 2 is provided with an air inlet connecting to the transition cavity 15. More specifically, a microporous filter membrane covering the air inlet is also arranged inside the horizontal tube 2. The microporous filter membrane of the present invention is a filter membrane with micro- and nano-sized pores, mainly used for preliminary filtration of secretions and water vapor in carbon dioxide in the end-respiratory gas. It can be a waterproof and breathable membrane commonly used in the art, such as GOEL-IP67 / 68*6B from Shaanxi Xintaitongda New Material Co., Ltd.

[0039] For some specific implementation methods, please refer to [link / reference]. Figure 1 As shown, the area of ​​the transition cavity 15 near the gas sampling tube 11 and the liquid sampling tube 12 is shaped like a trumpet with a gradually increasing inner diameter. The trumpet shape facilitates the condensation of water vapor in the inhaled gas, thereby enabling layered sampling in conjunction with the subsequent gas sampling tube 11 and liquid sampling tube 12.

[0040] For some specific implementation methods, please refer to [link / reference]. Figure 1As shown, a hydrophobic plate 14 is also provided in the middle and rear section of the transition cavity 15, and there is a gap between the end of the hydrophobic plate 14 and the gas sampling tube 11. The hydrophobic plate 14 has a hydrophobic coating. During the movement of the gas in the transition cavity 15, some water vapor will continue to condense on the hydrophobic plate 14 and flow along the path of travel, then drip from the gap between the hydrophobic plate 14 and the gas sampling tube 11 and enter the liquid sampling tube 12. In addition, the hydrophobic plate 14 can be installed by fixing both ends to the side wall of the transition cavity 15, or by fixing one end to the side wall of the transition cavity 15 and tilting the other end downward, with its direction being approximately parallel to the inlet of the gas sampling tube 11.

[0041] For some specific implementation methods, please refer to [link / reference]. Figure 1 As shown, the intermediate region between the gas sampling tube 11 and the liquid sampling tube 12 is further provided with an interconnected intermediate channel 16. In a more specific embodiment, the intermediate channel 16 is further provided with a one-way valve 13 that can only be opened toward the liquid sampling tube 12. The one-way valve 13 allows residual liquid in the gas sampling tube 11 to enter the liquid sampling tube 12, while the gas containing water vapor in the liquid sampling tube 12 will not enter the gas sampling tube 11 in large quantities, thus achieving approximately stratified sampling in the gas sampling tube 11 and the liquid sampling tube 12.

[0042] For some specific implementation methods, please refer to [link / reference]. Figure 1 As shown, the gas-liquid separator 3 is further provided with a partition plate 33, which divides the gas-liquid separator 3 into a gas cavity 31 located above and a liquid cavity 32 located below. The gas cavity 31 is connected to the gas sampling tube 11, and the liquid cavity 32 is connected to the liquid sampling tube 12. The partition plate 33 is provided with vent holes. The vent holes can be arranged into micro-nano pores of micro-nano size, which on the one hand does not affect the communication between the gas cavity 31 and the liquid cavity 32, and on the other hand can reduce the entry of water vapor and other substances in the liquid cavity 32 into the gas cavity 31, thus ensuring the purity of the gas in the gas cavity 31.

[0043] In a more specific embodiment, while ensuring the breathability of the partition plate 33, a waterproof and breathable membrane covering the breathable holes is also provided on the partition plate 33, so as to further filter water vapor and other substances.

[0044] In a more specific embodiment, the separator 33 includes an edge region that connects to the inner wall of the gas-liquid separator 3, and a central body integrally formed with and connected to the edge region. The height of the central body is not lower than that of the edge region, forming a liquid collection trough 36 with an upper opening between the edge region and the inner wall of the gas-liquid separator 3. With this structure, where the central body is higher and the edge region is lower, the droplets formed by the condensation of the last remaining water vapor in the gas cavity 31 will collect in the liquid collection trough 36, preventing the droplets from blocking the venting openings on the separator 33 and affecting the stratified sampling process. Additionally, the upper surface of the separator 33 can be hydrophobically treated, i.e., coated with a hydrophobic coating. Furthermore, an openable and closable opening can be provided at the lowest point of the edge region to facilitate the discharge of droplets collected in the liquid collection trough 36.

[0045] In a more specific embodiment, the gas cavity 31 is also provided with an interface on the separator tank for connecting to an external end-tidal carbon dioxide monitoring module.

[0046] In a more specific embodiment, the bottom of the liquid cavity 32 is also provided with a lower interface of the separation tank, and a liquid collection filter 34 and a drain valve 35 are sequentially provided at the lower interface of the separation tank, which can control the discharge of liquid in the gas-liquid separation tank 3 to maintain the cleanliness of the tank.

[0047] Each of the above implementation methods can be implemented individually, or in any combination of two or more.

[0048] The above implementation methods will be described in more detail below with reference to specific embodiments.

[0049] Example 1:

[0050] To address issues such as interference and blockage from water vapor and condensate, and to provide high-quality auxiliary monitoring for clinical use, thereby improving the accuracy of diagnosis and treatment, this embodiment provides a collection device for assisting in the monitoring of end-tidal carbon dioxide. Its structure can be found in [reference needed]. Figure 1 As shown, it includes:

[0051] 2, used to connect to the patient's breathing circuit;

[0052] The dual-cavity sampling tube 1 includes a transition cavity 15 connected to the horizontal tube 2, and a gas sampling tube 11 and a liquid sampling tube 12 connected to the transition cavity 15, wherein the gas sampling tube 11 is located above the liquid sampling tube 12.

[0053] And a gas-liquid separator 3 that connects the gas sampling tube 11 and the liquid sampling tube 12.

[0054] The horizontal tube 2 is provided with an air inlet port connecting to the transition cavity 15. A microporous filter membrane covering the air inlet port is also arranged inside the horizontal tube 2. The microporous filter membrane of this invention is a filter membrane with micro- and nano-sized pores, mainly used for preliminary filtration of secretions and water vapor in the end-respiratory gas, such as carbon dioxide. It can be a commonly used waterproof and breathable membrane in the art, such as GOEL-IP67 / 68*6B from Shaanxi Xintaitongda New Material Co., Ltd.

[0055] Please see again. Figure 1 As shown, the area of ​​the transition cavity 15 near the gas sampling tube 11 and the liquid sampling tube 12 is shaped like a trumpet with a gradually increasing inner diameter. The trumpet shape facilitates the condensation of water vapor in the inhaled gas, thereby enabling layered sampling in conjunction with the subsequent gas sampling tube 11 and liquid sampling tube 12.

[0056] Please see again. Figure 1 As shown, a hydrophobic plate 14 is also provided in the middle and rear section of the transition cavity 15, and there is a gap between the end of the hydrophobic plate 14 and the gas sampling tube 11. The hydrophobic plate 14 has a hydrophobic coating. During the movement of the gas in the transition cavity 15, some water vapor will continue to condense on the hydrophobic plate 14 and flow along the path of travel, then drip from the gap between the hydrophobic plate 14 and the gas sampling tube 11 and enter the liquid sampling tube 12. In addition, the hydrophobic plate 14 can be installed by fixing both ends to the side wall of the transition cavity 15, or by fixing one end to the side wall of the transition cavity 15 and tilting the other end downward, with its direction being approximately parallel to the inlet of the gas sampling tube 11.

[0057] Please see again. Figure 1 As shown, the gas-liquid separator 3 is further provided with a partition plate 33, which divides the gas-liquid separator 3 into a gas cavity 31 located above and a liquid cavity 32 located below. The gas cavity 31 is connected to the gas sampling tube 11, and the liquid cavity 32 is connected to the liquid sampling tube 12. The partition plate 33 is provided with vent holes. The vent holes can be arranged into micro-nano pores of micro-nano size, which on the one hand does not affect the communication between the gas cavity 31 and the liquid cavity 32, and on the other hand can reduce the entry of water vapor and other substances in the liquid cavity 32 into the gas cavity 31, thus ensuring the purity of the gas in the gas cavity 31.

[0058] Please see Figure 1As shown, the separator 33 includes an edge region that connects to the inner wall of the gas-liquid separator 3, and a central body integrally formed with and connected to the edge region. The height of the central body is not lower than that of the edge region, forming a liquid collection trough 36 with an upper opening between the edge region and the inner wall of the gas-liquid separator 3. With this structure, where the central body is higher and the edge region is lower, the droplets formed by the condensation of the last remaining water vapor in the gas cavity 31 will collect in the liquid collection trough 36, preventing the droplets from clogging the venting openings on the separator 33 and affecting the stratified sampling process. Additionally, the upper surface of the separator 33 can be hydrophobically treated, i.e., coated with a hydrophobic coating. Furthermore, an openable and closable opening can be provided at the lowest point of the edge region to facilitate the discharge of droplets collected in the liquid collection trough 36.

[0059] The gas cavity 31 is also provided with an upper interface for connecting to an external end-tidal carbon dioxide monitoring module. The bottom of the liquid cavity 32 is also provided with a lower interface for the separation tank. A liquid collection filter 34 and a drain valve 35 are sequentially installed at the lower interface for the separation tank, which can control the discharge of liquid in the gas-liquid separation tank 3 to maintain the cleanliness of the tank.

[0060] When a patient needs to monitor end-tidal carbon dioxide (etCO2) concentration, connect the horizontal tube 2 of this device to the front end of the Y-type port of the mechanical ventilation line or the exhaled gas end of a normal patient. Keep the line in the correct position, with the gas sampling tube 11 on the upper layer and the liquid sampling tube 12 on the lower layer. Connect the collector to the monitoring module.

[0061] The steps for using the collection device in this embodiment during operation are as follows:

[0062] (1) Connection device: Connect the entire device to the patient’s breathing circuit using the horizontal tube 2, ensuring a tight connection without leakage.

[0063] (2) Start monitoring: Start the end-tidal carbon dioxide monitoring equipment to ensure that all parts are working properly.

[0064] (3) Monitoring CO2 concentration: Monitor the CO2 curve on the display screen and the displayed CO2 concentration data. Based on this data, medical staff can determine the patient's respiratory status and CO2 concentration.

[0065] (4) Maintenance: Regularly inspect and clean all parts of the device, especially the liquid collection filter 34 and the drain valve 35, to ensure the proper operation and accuracy of the device.

[0066] In the specific process, the collection device of this embodiment uses a hydrophobic plate 14 to initially filter the moisture in the exhaled air. A dual-chamber pipe separates the exhaled air from components such as water vapor and condensate. The principle of this device is mainly based on the difference in gravity between water and gas, causing water or water vapor to be drawn into the gas-liquid separator 3 from the lower pipe, while gas is collected in the gas-liquid separator 3 from the upper pipe. An intermediate channel 16 with a one-way valve 13 is provided between the gas sampling tube 11 and the liquid sampling tube 12. Any moisture that accidentally enters the gas sampling tube 11 is then drawn back into the lower liquid sampling tube 12. Finally, the negative pressure generated when connected to the external end-of-breath carbon dioxide monitoring module is used to collect the moisture from both the gas and exhaled air, achieving accurate monitoring of the exhaled air CO2 concentration and solving problems such as water vapor interference and pipe blockage by condensate.

[0067] Example 2:

[0068] Based on Example 1, this example further adopts the following arrangement: while ensuring the air permeability of the partition plate 33, the partition plate 33 is also provided with a waterproof and breathable membrane covering the air permeable holes, and the waterproof and breathable membrane is used to further filter water vapor and the like.

[0069] Example 3:

[0070] Based on Example 1, this example further adopts the following arrangement, please refer to [link / reference]. Figure 1 As shown, the intermediate region between the gas sampling tube 11 and the liquid sampling tube 12 is further provided with an interconnected intermediate channel 16. In a more specific embodiment, the intermediate channel 16 is also provided with a one-way valve 13 that can only be opened toward the liquid sampling tube 12. The one-way valve 13 allows the liquid remaining in the gas sampling tube 11 to enter the liquid sampling tube 12, while the gas containing water vapor in the liquid sampling tube 12 will not enter the gas sampling tube 11 in large quantities, thus achieving roughly stratified sampling in the gas sampling tube 11 and the liquid sampling tube 12. The one-way valve 13 is generally arranged in the lower middle region of the intermediate channel 16. When a certain amount of liquid accumulates in the groove formed by the one-way valve 13 and the upper part of the intermediate channel 16, the one-way valve 13 will open. The one-way valve 13 can also be replaced with a structural component commonly used in the art that can achieve a corresponding one-way opening function.

[0071] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A collection device for assisting in the monitoring of carbon dioxide at the end of the respiratory tract, characterized in that, include: Used to connect to the horizontal tube in the patient's breathing circuit; A dual-cavity sampling tube includes a transition cavity connected to the horizontal tube, and a gas sampling tube and a liquid sampling tube connected to the transition cavity, wherein the gas sampling tube is located above the liquid sampling tube; And a gas-liquid separator connecting the gas sampling tube and the liquid sampling tube; The horizontal tube is provided with an air inlet that connects to the transition cavity, and a microporous filter membrane covering the air inlet is also arranged inside the horizontal tube. The area of ​​the transition cavity near the gas sampling tube and the liquid sampling tube is funnel-shaped with a gradually increasing inner diameter. The middle and rear section of the transition cavity is also provided with a hydrophobic plate, and there is a gap between the end of the hydrophobic plate and the gas sampling tube; The gas sampling tube and the liquid sampling tube are also provided with an intermediate channel that is interconnected. The gas-liquid separator is also equipped with a partition plate, which divides the gas-liquid separator into an upper gas cavity and a lower liquid cavity. The gas cavity is connected to the gas sampling tube, and the liquid cavity is connected to the liquid sampling tube. The partition plate is provided with a vent hole.

2. The collection device for assisting in monitoring end-tidal carbon dioxide according to claim 1, characterized in that, The intermediate channel is also equipped with a one-way valve that can only be opened toward the liquid sampling tube.

3. The collection device for assisting in monitoring end-tidal carbon dioxide according to claim 1, characterized in that, The partition plate is also provided with a waterproof and breathable membrane covering the ventilation holes.

4. The collection device for assisting in monitoring end-tidal carbon dioxide according to claim 1, characterized in that, The partition plate includes an edge region that connects with the inner wall of the gas-liquid separator, and a central body that is integrally formed with the edge region. The height of the central body is not lower than that of the edge region, so that a liquid collection trough with an upper opening is formed between the edge region and the inner wall of the gas-liquid separator.

5. A collection device for assisting in monitoring end-tidal carbon dioxide according to claim 1, characterized in that, The gas cavity is also equipped with an interface on the separator tank for connecting to an external end-tidal carbon dioxide monitoring module. The bottom of the liquid cavity is also provided with a lower interface of the separator tank, and a liquid collection filter and a drain valve are sequentially installed at the lower interface of the separator tank.

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