Tracheal tube for airway surface anesthesia

Abstract

The application provides a tracheal catheter for airway surface anesthesia, which comprises a catheter body, at least one cuff and at least one anesthesia drug delivery channel. The catheter body is internally provided with a main ventilation cavity; the cuff is arranged on the outer wall of the distal end of the catheter body; the anesthesia drug delivery channel extends along the inner wall of the catheter body or is attached to the outer wall, and the proximal end of the anesthesia drug delivery channel is provided with a drug injection interface, and the distal end of the anesthesia drug delivery channel is communicated with at least one drug outlet; the drug outlet is arranged on the outer wall of the catheter body and / or the surface of the cuff, and is used for directly releasing the anesthesia drug to the mucous membrane surface of the airway. The application can realize precise and controllable airway surface anesthesia, significantly reduce the cardiovascular stress reaction during intubation and extubation, improve the comfort of patients, reduce the systemic side effects of anesthesia drugs, and is especially suitable for conscious intubation and cardiovascular high-risk patients.

Description

Technical Field

[0001] This invention relates to the medical field, and more specifically to a tracheal tube for airway surface anesthesia. Background Technology

[0002] Endotracheal intubation is a core procedure in general anesthesia and airway management for critically ill patients. During intubation and extubation, the endotracheal tube's passage through the glottis and cuff compressing the tracheal mucosa can easily trigger intense sympathetic excitation, manifesting as a sudden rise in blood pressure, tachycardia, coughing, and agitation, which is particularly dangerous for patients with hypertension, coronary heart disease, or intracranial hypertension. Traditional methods of airway surface anesthesia, such as aerosol inhalation and cricothyroid membrane puncture injection, have drawbacks such as uneven drug diffusion, uncontrollable anesthetic effects, and complex procedures. Furthermore, conventional endotracheal tubes lack drug delivery capabilities, making it impossible to provide supplemental airway surface anesthesia after intubation or during prolonged mechanical ventilation. Therefore, there is an urgent need for an endotracheal tube capable of providing precise, controllable, and continuous airway surface anesthesia. Summary of the Invention

[0003] The problem to be solved by the present invention is to provide a tracheal tube for airway surface anesthesia that can play a role in local anesthesia, in order to overcome the above-mentioned shortcomings of the prior art.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a tracheal tube for airway surface anesthesia, comprising: a tube body having a distal end and a proximal end, and having a main ventilation channel inside; at least one inflatable / contractable cuff disposed on the distal outer wall of the tube body; at least one anesthetic drug delivery channel extending along the inner wall of the tube body or attached to the outer wall, the proximal end of the delivery channel having an injection port, and the distal end communicating with at least one drug outlet; the drug outlet being disposed on the outer wall of the tube body and / or the surface of the cuff, for directly releasing anesthetic drugs to the airway mucosal surface.

[0005] Furthermore, the drug delivery port includes multiple segmented nozzles distributed along the axial direction of the catheter body, corresponding to anatomical locations in the glottic region, mid-trachea, and above the carina, respectively. Each segmented nozzle achieves segmented and controllable drug delivery through an independent anesthetic drug delivery channel and an independent injection interface. This allows clinicians to selectively administer drugs at different anatomical sites as needed.

[0006] Furthermore, the cuff is a semi-permeable cuff, with its inner lumen connected to an independent anesthetic drug delivery channel. By injecting anesthetic drugs under pressure into the semi-permeable cuff, the drugs are evenly distributed on the outer surface of the cuff through permeation or micro-perforation, achieving continuous surface anesthesia in the cuff contact area. This design allows for the release of anesthetic drugs while the cuff is inflated and compresses the tracheal mucosa, effectively suppressing coughing and cardiovascular responses caused by cuff stimulation.

[0007] Furthermore, the outer wall of the catheter body is provided with a hygroscopic permeable layer, which is connected to at least one drug outlet; when anesthetic drugs are injected into the permeable layer through the delivery channel, the drugs diffuse along the permeable layer and are slowly released to the contacting airway mucosa. This permeable layer can be made of medical sponge, microporous polymer, or woven fabric to achieve a sustained-release effect.

[0008] Furthermore, the drug outlet is a laser-processed microporous structure with a pore size of ~μm. Multiple micropores are arranged in a spiral or ring shape on the outer wall of the distal end of the catheter body. Under an injection pressure of .~.MPa, the anesthetic drug is released in a spray-like diffusion manner through the micropores, which can increase the drug coverage area and reduce liquid impact damage.

[0009] Furthermore, it also includes a visual sensor located at the distal end of the catheter body or near the cuff. The visual sensor is connected to a proximal display or light source via a signal line embedded in the catheter wall, and is used to guide the spraying and positioning of anesthetic drugs under direct vision. The visual sensor can be a miniature CMOS camera or a fiber optic imaging bundle.

[0010] Furthermore, an auxiliary oxygen supply bypass is provided on the inner or outer wall of the main ventilation channel of the catheter body. The distal opening of the auxiliary oxygen supply bypass is adjacent to the drug outlet, which is used to blow oxygen at a flow rate of ~ L / min while administering the drug. The oxygen flow helps to atomize the anesthetic drug and clear airway secretions, promoting uniform adhesion of the drug to the mucosa.

[0011] Furthermore, the injection port is equipped with a one-way valve or a screw-locking connector to prevent anesthetic drug backflow and to achieve a sealed connection with the syringe.

[0012] Furthermore, the inner wall of the outer side of the delivery channel forms multiple recesses, and the main draw wire is provided inside the wall of the conduit body, which penetrates the recesses.

[0013] Compared with existing technologies, the present invention has the following beneficial effects: significantly reduces cardiovascular stress response during intubation, extubation and mechanical ventilation; improves patient comfort, especially suitable for awake intubation or difficult airway patients; reduces systemic absorption of anesthetic drugs and reduces toxic side effects; enables segmented, continuous and visualized precise drug delivery; has a simple structure and is easy to integrate into existing endotracheal tube manufacturing processes.

[0014] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of an endotracheal tube used for airway surface anesthesia.

[0016] Figure 2This is a schematic diagram of the structure of a catheter body.

[0017] Figure 3 A schematic diagram of the tube wall structure of the catheter body. Detailed Implementation

[0018] To make the technical means, creative features, objectives, and effects of this invention clearer and easier to understand, the invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0019] Example 1

[0020] An endotracheal tube for airway surface anesthesia includes a tube body 1, with an inflatable cuff 2 fixed to the outer wall of its distal end (insertion end). An axial anesthetic drug delivery channel 3 is embedded within the wall of the tube body 1. The proximal end of this channel 3 is connected to an injection port 4 (e.g., a standard Luer connector), and the distal end passes through the cuff 2, with multiple outlet ports 5 on its surface. In use, the tube is inserted into the trachea and the cuff 2 is inflated. Local anesthetics such as lidocaine are injected through the injection port 4. The drug seeps out through the delivery channel 3 from the outlet ports 5, acting directly on the tracheal mucosa to achieve surface anesthesia. The outlet ports 5 are three independent segmented nozzle groups 6, located on the tube body 1 corresponding to the glottis, mid-trachea, and above the carina, respectively. Each nozzle group is controlled by an independent delivery channel 3 and injection port 4. The physician can sequentially inject small amounts of anesthetic to different sites as needed, achieving stepwise anesthesia. The cuff 2 is made of a semi-permeable silicone membrane, forming a semi-permeable cuff 7. A delivery channel 3 communicates with the inner lumen of a semi-permeable cuff 7. After anesthetic is injected into the cuff, the drug solution permeates evenly to the outer surface through the micropores of the cuff wall under pressure, releasing the anesthetic as the cuff contacts the tracheal wall, making it particularly suitable for patients with prolonged intubation. A layer of medical-grade polyvinyl alcohol sponge serves as a hygroscopic and permeable layer 8, covering the outer wall of the catheter body 1. The distal end of the delivery channel 3 opens inside the permeable layer 8. After anesthetic injection, the drug first wets the sponge layer and is then slowly released into the airway mucosa; a single administration can last for 30-60 minutes.

[0021] Multiple micropores 9, each 50 μm in diameter, are formed on the distal outer wall of the catheter body 1 using laser drilling, arranged in a spiral pattern. When the syringe injects anesthetic, a pressure of 0.2 MPa is generated, causing the anesthetic to atomize and spray out through the micropores 9, providing wide coverage without forming droplet impact. A miniature CMOS visual sensor 10 is installed above the cuff 2, with its signal line led along the inner wall of the catheter to a proximal display. Simultaneously, an auxiliary oxygen supply bypass 11 is provided within the catheter body, with its opening located near the micropores 9. During drug administration, oxygen is blown at a rate of 1 L / min, which propels the atomized drug solution against the airway wall and dissipates sputum. Combined with a direct-view image, precise drug delivery is achieved. A one-way valve 12 is installed between the injection port 4 and the delivery channel 3 to prevent backflow of drug solution or gas after the syringe is withdrawn, ensuring accurate dosage.

[0022] Example 2

[0023] The catheter body 1 is made of medical-grade polyvinyl chloride or polyurethane material, and has a distal end (insertion end) and a proximal end (operation end). It has an axially extending main ventilation channel inside for connecting to a ventilator for positive pressure ventilation. The cuff 2 is an inflatable or deflated elastic bladder that surrounds and is fixed to the distal outer wall of the catheter body 1. It is made of a highly compliant polyurethane film. The cuff 2 is connected to the proximal inflation indicator balloon and one-way valve via an independent inflation line. It is used to inflate after intubation to close the airway, fix the catheter, and provide positive pressure ventilation. The anesthetic drug delivery channel 3 is a capillary lumen with an inner diameter of approximately 0.5 to 1.0 mm, integrally formed inside the tube wall during the extrusion molding of the catheter body 1, extending axially from the proximal end to the distal end. The injection port 4 is fixed to the proximal end of the delivery channel 3, is a standard medical Luer connector, and has a built-in one-way valve 12, such as a duckbill valve or a cross-slit valve. The one-way valve 12 allows the syringe to open in the forward direction when injecting anesthetic drugs and automatically closes after injection stops, effectively preventing airway secretions or residual medication from flowing back and contaminating the tubing. The dispensing port 5 is located on the surface of the cuff wall 2. The distal end of the delivery channel 3 passes through the fixed end of the cuff 2 and opens directly onto the outer surface of the cuff 2. Working principle and process: After the endotracheal tube is inserted into the patient's trachea and its position is confirmed, an appropriate amount of air is injected into the cuff 2 through the inflation tubing to inflate it and seal the trachea. Subsequently, the clinician uses a syringe containing a local anesthetic, such as 2% lidocaine solution, connected to the injection port 4. During injection, the drug solution overcomes the resistance of the one-way valve 12 and enters the anesthetic drug delivery channel 3. Finally, it seeps out directly or is slowly sprayed out from the drug outlet 5 on the surface of the cuff 2. Because the outer wall of the cuff 2 is tightly attached to the tracheal mucosa, the released anesthetic drug can act directly and at a high concentration on the mucosal area compressed by the cuff, thereby accurately inhibiting coughing and cardiovascular stress response caused by cuff stimulation. The design of the one-way valve 12 ensures that no secretions are aspirated back into the delivery channel 3 during the entire mechanical ventilation process.

[0024] Example 3

[0025] The drug outlet 5 is not a single opening, but is composed of multiple groups of nozzles distributed along the axial direction of the catheter body 1. Specifically, it includes a first nozzle group 6a, a second nozzle group 6b, and a third nozzle group 6c. When the catheter is inserted to a standard depth, such as 22 to 24 cm from the incisors, the first nozzle group 6a is located in the glottis, the second nozzle group 6b is located in the middle of the trachea, and the third nozzle group 6c is located above the carina.

[0026] Independent delivery channels and interfaces: Each segmented nozzle group 6a, 6b, and 6c is connected to an independent anesthetic drug delivery channel 3a, 3b, and 3c, respectively. The proximal end of each channel is connected to an independent injection interface 4a, 4b, and 4c. Each injection interface is marked with a different color or shape for easy identification and is equipped with a one-way valve 12.

[0027] Working principle and process: This design enables segmented and controllable drug delivery. For example, during awake intubation, the physician can first inject 0.5 to 1 ml of anesthetic into the glottic area through interface 4a connected to the first nozzle group 6a, and then proceed with intubation after the glottic reflex is suppressed. After intubation, if the patient experiences coughing due to the catheter tip irritating the carina, additional medication can be administered above the carina through interface 4c connected to the third nozzle group 6c. This design avoids drug waste and excessive absorption caused by uniform spraying, achieving on-demand and precise stepwise anesthesia.

[0028] Example 4

[0029] The semi-permeable cuff 7 is made of a special semi-permeable medical material, such as a silicone membrane or a nanoporous polytetrafluoroethylene composite membrane with a specific microporous structure and a pore size of less than 5 micrometers. After inflation, the cuff wall allows liquid drugs to slowly pass through under pressure via permeation or exudation, while gas molecules such as air and oxygen have difficulty passing through. The cuff 2 itself is the semi-permeable cuff 7. An independent anesthetic drug delivery channel 3 is directly connected to the inner cavity of the semi-permeable cuff 7. Working principle and process: After intubation and fixation, a certain amount of liquid anesthetic drug, such as ropivacaine, is first injected into the semi-permeable cuff 7 through the anesthetic drug delivery channel 3. Subsequently, air is injected into the cuff through a conventional inflation tube to achieve the pressure required to seal the airway. Under the action of air pressure, the liquid anesthetic drug inside the cuff is squeezed and permeates evenly and continuously through the semi-permeable cuff wall to the outer surface of the cuff. In this way, the tracheal mucosa area in contact with the cuff can be stably anesthetized for several hours throughout the entire mechanical ventilation period, effectively suppressing cardiovascular fluctuations caused by long-term stimulation, and eliminating the need for repeated interventions by medical staff. When the anesthetic is depleted, it can be replenished through delivery channel 3.

[0030] Hygroscopic Permeable Layer 8: A hygroscopic permeable layer 8 is coated or fitted onto the distal outer wall of the catheter body 1, excluding the area occupied by the cuff 2. This permeable layer 8 is made of a biocompatible porous material, such as medical polyvinyl alcohol sponge, polyurethane foam, or woven nylon mesh, with a thickness of approximately 0.5 to 1.5 mm. Connection method: At least one drug outlet 5 is completely covered and connected by this hygroscopic permeable layer 8. The distal opening of the anesthetic drug delivery channel 3 is located deep inside the permeable layer 8. Working principle and process: During operation, a relatively large dose of anesthetic drug, such as 3 to 5 ml, is injected through the injection port 4. The drug solution first enters the interior of the hygroscopic permeable layer 8 through the delivery channel 3 and rapidly diffuses along the longitudinal and radial directions of the permeable layer under capillary action, being adsorbed by the entire permeable layer structure. Because the permeable layer 8 is exposed to a warm and humid airway environment, the adsorbed drug is slowly released from the pores of the sponge or fabric to the contacted airway mucosa surface through molecular diffusion. This design allows for a single dose to extend the effective anesthesia time to 30 to 60 minutes or more, making it particularly suitable for scenarios with moderate expected intubation time or where fewer nursing procedures are required.

[0031] The drug outlet 5 employs a micropore structure 9 fabricated using high-precision laser processing technology such as femtosecond laser. The diameter of each micropore 9 is precisely controlled within the range of 10 to 200 micrometers, preferably 50 micrometers. Arrangement: The multiple micropores 9 are not randomly distributed, but rather arranged in a spiral or multi-row ring pattern on the outer wall of the distal end of the catheter body 1, which is not covered by the sheath. This spiral arrangement helps to form a uniform drug distribution in the circumferential direction of the catheter. It is used in conjunction with a specific injection pressure. When used in conjunction with a low-viscosity anesthetic solution with low resistance, such as 1% lidocaine, and when a pressure of approximately 0.1 to 0.5 MPa is generated using a hand-operated syringe, the solution is sheared and broken into tiny atomized particles through micropores 9, forming a spray-like diffusion release. Working principle and process: Compared to directly flowing liquids or large droplets, spray-like release has significant advantages: First, it covers a wider area, diffusing into the annular gap between the catheter and the tracheal wall, as well as the posterior wall; second, the particles are small, causing less impact on the sensitive airway mucosa and avoiding coughing; third, the atomized particles bind more easily to the mucosa, resulting in high absorption efficiency. In clinical use, the anesthetic can be rapidly injected during or after intubation to provide rapid, uniform, and gentle surface anesthesia to the airway segment containing the catheter. Visual sensor 10: This is a miniaturized CMOS image sensor, no larger than 1.0 mm x 1.0 mm, sealed and installed at the distal end of the catheter body 1, near the cuff 2. Two extremely thin copper shielded signal wires are embedded in the wall of the catheter body 1, serving as signal lines. One end is connected to the visual sensor 10, and the other end extends proximally and connects to a standard video processing and display device, such as a portable monitor and a cold light source. The auxiliary oxygen supply bypass 11 is another independent, small cavity embedded in the wall of the catheter body 1. Its distal opening, the air outlet, is carefully positioned adjacent to the direction of drug ejection from the drug outlet 5 or micro-orifice 9. Its proximal end connects to a standard oxygen interface, capable of supplying medical oxygen at a flow rate of 0.5 to 2 liters per minute. Guidance and positioning: During or after intubation, the real-time images transmitted by the visual sensor 10 are observed through the display device. The doctor can clearly identify anatomical structures such as the glottis, tracheal rings, and carina, and precisely guide the drug outlet 5 to the target mucosal area requiring anesthesia, such as the carina. After determining the location, the anesthetic is injected. Simultaneously, oxygen is blown through the auxiliary oxygen supply bypass 11 at a flow rate of approximately 1 liter per minute. The oxygen flow creates a local positive pressure and airflow field at the tip of the catheter, which has the following effects: First, it further disperses and blows the sprayed nebulized drug solution toward the target mucosa; second, it blows away secretions or sputum covering the mucosal surface so that the drug can directly contact the mucosa; third, it provides a local oxygen-rich environment to avoid transient decrease in blood oxygen caused by high concentrations of drug solution.

[0032] Considering that the conveying channel 3 is very small due to its size being set on the pipe wall, in order to increase the conveying speed, multiple recesses 13 are formed on the outer side of the inner wall of the conveying channel 3. A main drawing wire 14 is provided inside the pipe wall of the conduit body 1, and the main drawing wire 14 passes through the recesses 13. The tail end of the main drawing wire 14 is fixed to the pipe wall of the conduit body 1, and the head end of the main drawing wire 14 passes through the pipe wall of the conduit body 1 and connects to a locking member. The locking member is sleeved on the main drawing wire 14. The main draw wire 14 has an elastic rubber ring at its head end, which has a through hole through which the head end of the main draw wire 14 passes. The through hole is pressurized with the main draw wire 14 to clamp it. The inner wall of the catheter body 1 has a sliding channel for the main draw wire 14 to move. The main draw wire 14 has multiple side draw wires that are connected to the inner wall of the recess 13. When the main draw wire 14 is pulled, the side draw wires pull the inner wall of the recess 13 to increase the injection speed and achieve multi-stage pressure increase.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An endotracheal tube for airway surface anesthesia, characterized in that, include: The catheter body (1) has a distal end and a proximal end, and has a main ventilation channel inside; at least one expandable / contractable cuff (2) is disposed on the distal outer wall of the catheter body (1); at least one anesthetic drug delivery channel (3) extends along the inner wall of the catheter body (1) or is attached to the outer wall, the proximal end of the delivery channel (3) is provided with an injection port (4), and the distal end is connected to at least one drug outlet (5); the drug outlet (5) is disposed on the outer wall of the catheter body (1) and / or the surface of the cuff (2), for releasing anesthetic drugs directly to the airway mucosa surface.

2. The endotracheal tube according to claim 1, characterized in that, The outlet (5) includes multiple segmented nozzles (6) distributed along the axial direction of the catheter body (1), corresponding to the anatomical locations of the glottis, the middle section of the trachea and the carina, respectively. Each segmented nozzle (6) achieves segmented and controllable drug delivery through an independent anesthetic drug delivery channel (3) and an independent drug injection interface (4).

3. The endotracheal tube according to claim 1, characterized in that, The cuff (2) is a semi-permeable cuff (7), the inner cavity of which is connected to an independent anesthetic drug delivery channel (3); by injecting anesthetic drugs into the semi-permeable cuff (7) under pressure, the drugs are evenly distributed on the outer surface of the cuff by permeation or micro-pore spraying, so as to achieve continuous surface anesthesia in the cuff contact area.

4. The endotracheal tube according to claim 1, characterized in that, The outer wall of the catheter body (1) is provided with a hygroscopic permeable layer (8), which is connected to at least one drug outlet (5); when the anesthetic drug is injected into the permeable layer (8) through the delivery channel (3), the drug diffuses along the permeable layer (8) and is slowly released to the contacted airway mucosa.

5. The endotracheal tube according to claim 1, characterized in that, The drug outlet (5) is a laser-processed micropore (9) structure with a pore size of 10~200μm. Multiple micropores (9) are arranged in a spiral or ring shape on the outer wall of the distal end of the catheter body (1). Under an injection pressure of 0.1~0.5MPa, the anesthetic drug is released in a spray-like diffusion through the micropores (9).

6. The endotracheal tube according to claim 1, characterized in that, It also includes a visual sensor (10) located at the distal end of the catheter body (1) or near the cuff (2). The visual sensor (10) is connected to a proximal display or light source via a signal line embedded in the catheter wall and is used to guide the spraying and positioning of anesthetic drugs under direct vision.

7. The endotracheal tube according to claim 1, characterized in that, An auxiliary oxygen supply bypass (11) is provided on the inner or outer wall of the main ventilation channel of the catheter body (1). The distal opening of the auxiliary oxygen supply bypass (11) is adjacent to the drug outlet (5) and is used to blow oxygen at a flow rate of 0.5~2 L / min while injecting the drug.

8. The endotracheal tube according to claim 1, characterized in that, The injection port (4) is equipped with a one-way valve (12) or a screw-locking connector to prevent anesthetic drug backflow and achieve a sealed connection with the syringe.

9. The endotracheal tube according to claim 1, characterized in that, The inner wall of the outer side of the delivery channel (3) forms multiple recesses (13), and the main draw wire (14) is provided inside the tube wall of the catheter body (1), and the main draw wire (14) penetrates the recesses (13).

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