Small animal anesthesia experiment device

Abstract

The invention relates to the technical field of animal anesthesia experiments, and discloses a small animal anesthesia experiment device which comprises an electronic injection type atomization medicine feeding module used for forming a high-voltage electrostatic field and carrying out secondary atomization on anesthetic fog drops primarily atomized by the high-voltage electrostatic field through high-speed compressed air so as to generate anesthetic aerosol with the particle size of 1-5 microns and output the anesthetic aerosol; the induction cabin module is connected with the output end of the electronic injection type atomization medicine feeding module in a switchable mode; an animal anesthesia platform; the integrated mask module is connected with the output end of the electronic injection type atomization medicine feeding module in a switchable mode and used for monitoring the respiratory rate and / or the tidal volume of the experimental target wearing the mask in real time; the main control unit is electrically connected with the electronic injection type atomization medicine feeding module, the induction cabin module and the integrated mask module and used for adjusting the concentration of the anesthetic in the induction cabin module in the induction stage or dynamically adjusting the output amount of the anesthetic conveyed to the integrated mask module in the anesthesia maintaining stage.

Description

Technical Field

[0001] This invention relates to the field of animal anesthesia experimental technology, and in particular, to a small animal anesthesia experimental apparatus. Background Technology

[0002] In life science research, safe, stable, and reliable anesthesia of small mammals used in experiments (generally referred to as "small animals" in this field, typically including mice, rats, guinea pigs, hamsters, etc.) is a fundamental prerequisite for the successful execution of many experimental procedures. An ideal state of anesthesia requires the animal to maintain stable vital signs under conditions of painlessness and immobilization, which is crucial for ensuring surgical safety and the reproducibility of experimental data.

[0003] Currently, the main methods of anesthesia for these small animals are injection anesthesia and inhalation anesthesia, both of which have certain limitations.

[0004] Injection anesthesia is typically achieved by administering anesthetic drugs via intraperitoneal or intravenous injection. This method is simple to perform and has a rapid onset of action. However, due to significant individual differences in laboratory animals, precise control of the anesthetic dosage is challenging. Insufficient dosage may result in shallow anesthesia, causing the animal to awaken during surgery; while supplemental administration can easily lead to excessive anesthesia due to dose accumulation, causing risks such as respiratory depression. Furthermore, the depth of injection anesthesia is difficult to adjust flexibly and in real-time after administration, making it unsuitable for surgical procedures requiring prolonged maintenance of a stable anesthetic state.

[0005] Inhalation anesthesia uses volatile anesthetics such as isoflurane and sevoflurane, administered to the animal via specialized equipment. This method allows the anesthetic gas to be rapidly inhaled and exhaled, facilitating real-time control of the depth of anesthesia during surgery. Therefore, it is more suitable for delicate surgical procedures on small animals, such as thoracotomy, craniotomy, and laparotomy, which require prolonged manipulation. However, existing inhalation anesthesia techniques have the following main problems: 1. Currently widely used technologies such as ultrasonic nebulization or compressed gas nebulization produce anesthetic aerosols with relatively large particle sizes (usually greater than 5 μm) and a wide particle size distribution. Larger droplets tend to deposit in the upper respiratory tract of animals (such as the nasal cavity and trachea), making it difficult for them to effectively reach the alveoli for efficient absorption. This results in problems such as slow anesthesia induction, low drug utilization efficiency, and high consumption of anesthetic agents in small animals.

[0006] 2. Most existing small animal anesthesia equipment only provides the function of outputting anesthetic gas, failing to establish an automatic, real-time closed-loop feedback control between the delivery rate of the anesthetic and the real-time physiological state of the experimental animal (especially key parameters such as respiratory rate and tidal volume). Maintaining the depth of anesthesia mainly relies on the operator's experience, observation, and manual adjustment. This open-loop control mode struggles to respond quickly and accurately to fluctuations in the depth of anesthesia caused by individual differences and surgical stimuli during surgery. This not only increases the difficulty of maintaining a stable anesthetic state but also potentially affects the safety of the experimental animal and the stability of experimental results.

[0007] 3. In specific experimental procedures, the animal's position (such as supine for thoracotomy and prone for craniotomy) will cause changes in the orientation of its mouth and nose. However, the design of existing small animal anesthesia masks is usually relatively fixed, making it difficult to flexibly and conveniently adapt to the orientation and posture of the animal's head under different positions. This may affect the airtightness of the anesthetic gas delivery channel, thus adversely affecting the consistency of the anesthetic effect.

[0008] Therefore, existing inhalation anesthesia methods and devices for small animals still need improvement in terms of nebulization efficiency, intelligent control, and operational adaptability. There is an urgent need for an anesthesia system that can achieve efficient nebulization delivery, precise closed-loop control based on physiological signal feedback, and flexibly adapt to different experimental scenarios. Summary of the Invention

[0009] This invention provides a small animal anesthesia experimental device that generates submicron-sized anesthetic aerosols through a gas-assisted coaxial electrospray system. Based on real-time monitoring of animal respiratory signals, the device performs closed-loop feedback control of the aerosol output, enabling rapid switching between induction and maintenance modes and stable anesthesia adapted to different body positions. This addresses the technical problems in existing small animal inhalation anesthesia, such as low drug utilization efficiency due to large aerosol particle size, inaccurate control of anesthesia depth due to lack of physiological feedback, and inconsistent anesthetic effects due to poor device compatibility.

[0010] This invention provides a small animal anesthesia experimental device, comprising: an electro-injection nebulizer module for forming a high-voltage electrostatic field and using high-speed compressed air to atomize the anesthetic droplets initially atomized by the high-voltage electrostatic field to generate and output anesthetic aerosols with a particle size of 1μm-5μm; an induction chamber module, switchably connected to the output end of the electro-injection nebulizer module, for accommodating the experimental target and rapidly inducing anesthesia in the anesthetic aerosol environment; an animal anesthesia platform, located downstream of the induction chamber module, for supporting and fixing the experimental target for subsequent experiments; an integrated mask module, adjustablely positioned on the animal anesthesia platform and switchably connected to the output end of the electro-injection nebulizer module, for real-time monitoring of the respiratory rate and / or tidal volume of the experimental target wearing the mask; and a main control unit, electrically connected to the electro-injection nebulizer module, the induction chamber module, and the integrated mask module, for adjusting the anesthetic concentration in the induction chamber module during the induction phase, or dynamically adjusting the output of anesthetic delivered to the integrated mask module during the maintenance anesthesia phase.

[0011] Furthermore, the output end of the electro-injected nebulizer delivery module is set as a gas path switching module. The first output end of the gas path switching module is connected to the induction chamber module, and the second output end of the gas path switching module is connected to the integrated mask module. The gas path switching module is used to selectively deliver the anesthetic aerosol generated by the electro-injected nebulizer delivery module to either the induction chamber module or the integrated mask module.

[0012] Furthermore, the air path switching module includes: a valve body with an air inlet and an air outlet; a valve core rotatably disposed within the valve body, with an internal airflow channel; a drive mechanism connected to the valve core for driving the valve core to rotate to different working positions; a position detection element for detecting the rotational position of the valve core and outputting an electrical signal; the air inlet of the valve body is used to connect to the air delivery pipeline of the electronically injected atomized drug delivery module, and the two air outlets of the valve body are respectively connected to the induction chamber module and the integrated mask module.

[0013] Furthermore, a double O-ring seal is provided between the valve core and the valve body to ensure airtight isolation between the channels.

[0014] Furthermore, the valve core has an L-shaped channel structure. When the L-shaped channel structure is rotated to the first position, it connects the air inlet and the first air outlet. When it is rotated to the second position, it connects the air inlet and the second air outlet.

[0015] Furthermore, both the air inlet and outlet of the valve body are quick-connect female connectors. The quick-connect female connector of the air inlet of the valve body is matched with the quick-connect male connector at the end of the air supply pipeline to achieve quick connection and disconnection.

[0016] Furthermore, the drive mechanism is a manual knob, which has a position indicator arrow and a positioning feel mechanism.

[0017] Furthermore, the position detection element adopts a micro switch or a Hall sensor, and the signal of the position detection element is connected to the main control unit to control the start-up, shutdown or switching of the working mode of the electronically injected atomized drug delivery module.

[0018] Furthermore, the electro-injection nebulization drug delivery module includes an air-assisted coaxial electro-spray nozzle, a high-voltage electrostatic generator, a precision injection pump, and a compressed air source. The air-assisted coaxial electro-spray nozzle adopts a coaxial structure with internal liquid and external air. The inner layer of the air-assisted coaxial electro-spray nozzle is connected to the precision injection pump, and the outer layer of the air-assisted coaxial electro-spray nozzle is connected to the compressed air source. The high-voltage electrostatic generator is connected to the inner layer of the air-assisted coaxial electro-spray nozzle. The anesthetic liquid is delivered through the inner layer and a high-voltage electrostatic field is formed at the outlet to perform preliminary atomization of the anesthetic liquid. At the same time, high-speed compressed air introduced into the outer layer is used to perform secondary atomization of the anesthetic droplets that have been preliminarily atomized by the high-voltage electrostatic field to generate anesthetic aerosols with a particle size of 1μm-5μm and output them.

[0019] Furthermore, the air-assisted coaxial electro-spray nozzle includes an annular air path system and a central liquid path system. The annular air path system is coaxially sleeved outside the central liquid path system. The inner central liquid path system is connected to a precision injection pump, and the outer annular air path system is connected to a compressed air source. A high-voltage electrostatic generator is connected to the central liquid path system, which delivers anesthetic liquid and forms a high-voltage electrostatic field at the outlet to initially atomize the anesthetic liquid. The air chamber at the end of the annular air path system is used to form a gas-liquid mixing zone. The high-speed compressed air delivered by the annular air path system atomizes the anesthetic droplets that have been initially atomized by the central liquid path system a second time, generating anesthetic aerosols, which are then pushed into the air delivery pipeline and output.

[0020] Furthermore, the central fluid circuit system includes a central fluid needle, which is made of medical-grade 316L stainless steel capillary tube with an inner diameter of 0.15mm-0.8mm and an outer diameter of 0.6mm-1.0mm. The tip cone angle of the central fluid needle is 30°-60°. The central fluid needle is wrapped with an insulating sleeve, which is made of PEEK micro tubing with a wall thickness of 0.2mm-0.5mm. The inlet end of the central fluid needle is connected to a precision injection pump through a high-pressure isolation fluid circuit tube, and the outlet end of the central fluid needle is 1.0cm-3.0cm away from the annular gas circuit outlet.

[0021] Furthermore, the annular air circuit system includes an annular air chamber, which is a PEEK micro-tube with an annular gap width of 0.1mm-0.3mm and an annular diameter of 1.5mm-3.0mm. The air inlet of the annular air chamber is connected to a compressed air source, and the outer wall of the air outlet of the annular air chamber is provided with a copper ring, which is coaxially arranged with the annular air chamber and has a diameter of 2mm-5mm. An airflow rectification structure is set inside the annular air chamber. The airflow rectification structure adopts an annular perforated plate, on which multiple axial through holes are evenly distributed along the circumference. The diameter of the axial through holes is 0.2mm-0.5mm, and the plate thickness is 0.3mm-1.0mm.

[0022] Furthermore, the induction chamber module includes a housing; the top of the housing is a top cover that is sealed to the top opening by hinges, latches, and sealing strips, and the top cover is provided with an air outlet that is connected to the exhaust gas treatment device; the bottom of the housing is provided with an annular air distribution pipe and an air inlet, the air inlet being connected to the annular air distribution pipe, the annular air distribution pipe being densely covered with air distribution holes so that the gas enters through the air inlet and rises evenly through the air distribution holes of the annular air distribution pipe; the diameter of the air distribution holes is 0.3mm-0.8mm, the hole spacing is 5mm-15mm, and the opening direction of the air distribution holes forms an angle of 30°-60° with the horizontal plane so that the airflow is evenly dispersed in the chamber.

[0023] Furthermore, the induction chamber module also includes a concentration sensor. The concentration sensor is installed at the center of the inner wall of the chamber via a quick-connect sealing connector and is electrically connected to the main control unit. Based on the feedback signal from the concentration sensor, the main control unit adjusts the precision injection pump of the electro-injection nebulizer module through a PID control algorithm. The main control unit has preset PID parameters for different chamber volumes to facilitate automatic matching.

[0024] Furthermore, the air outlet of the housing is connected to an exhaust gas treatment device to adsorb the anesthetic in the discharged gas; a negative pressure sensor is installed on the pipeline between the air outlet and the exhaust gas treatment device to monitor the pipeline patency; the exhaust gas treatment device includes a replaceable activated carbon filter canister filled with an activated carbon layer; both the air inlet and outlet of the activated carbon filter canister are equipped with quick-connect fittings; at least one of the air inlet, outlet, or air inlet and outlet of the activated carbon filter canister is equipped with a one-way valve to prevent gas backflow.

[0025] Furthermore, the activated carbon filter canister is made of transparent material to facilitate observation of its internal condition; the activated carbon filter canister is also equipped with a pre-filter cotton layer and a post-filter cotton layer, which are located upstream and downstream of the activated carbon layer, respectively.

[0026] Furthermore, the output end of the induction chamber module and / or the output end of the integrated mask module are connected to the exhaust gas collection module via a pipeline with a one-way valve, and the mixing chamber outlet of the exhaust gas collection module is connected to the exhaust gas treatment device.

[0027] Furthermore, the integrated mask module includes a mask body with independent air inlets and outlets. Both the air inlets and outlets are equipped with one-way valves to allow gas to enter through the air inlet and exit through the air outlet. The air outlet of the mask body is configured with a split-flow airway structure, which includes a main flow channel and a sampling branch. The cross-sectional area of ​​the branch is 15% of the cross-sectional area of ​​the main flow channel. The inlet end of the main flow channel and the inlet end of the sampling branch converge at the inlet end of the air outlet, and the outlet end of the main flow channel and the outlet end of the sampling branch converge at the outlet end of the air outlet. The air outlet is connected to the exhaust gas treatment device via an exhaust gas hose. The top of the inner wall of the mask body is equipped with a nose pad structure to cooperate with the bridge of the nose of the experimental target to limit the depth of mouth and nose insertion and to ensure that the tip of the nose is aligned with the split point of the main flow channel and the sampling branch.

[0028] Furthermore, the enclosure also includes: a MEMS hot-film flow sensor chip, located within the sampling branch, for detecting the velocity and direction of respiratory airflow; a sensor mount for fixing the MEMS hot-film flow sensor chip onto the sampling branch and forming a sampling cavity; a signal conditioning circuit board, electrically connected to the MEMS hot-film flow sensor chip, for amplifying and filtering the sensor signal; a composite transmission cable, a multi-core shielded signal cable, with one end connected to a miniature aviation plug in the enclosure and the other end connected to the main control unit; and a main control unit, connected to the composite transmission cable and the electro-injected atomizing drug delivery module, including an isolation sampling circuit, a control output interface, and a digital signal processor.

[0029] Furthermore, the exhaust gas collection module has its first input end connected to the exhaust gas outlet of the induction chamber module via a pipeline with a one-way valve, and its second input end connected to the exhaust gas outlet of the integrated mask module via a pipeline with a one-way valve. The mixing chamber outlet of the exhaust gas collection module is connected to the exhaust gas treatment device, which is used to collect and guide the exhaust gas from the induction chamber module and / or the integrated mask module, and to prevent the exhaust gas from flowing back between the various passages.

[0030] Furthermore, the main control unit is electrically connected to the precision injection pump in the electro-injection nebulizer module, the concentration sensor in the induction chamber module, the MEMS hot-film flow sensor chip in the integrated mask module, and the gas path switching module, respectively. The main control unit is configured to: during the induction phase, control the flow rate of the precision injection pump in a closed loop based on the concentration signal fed back by the concentration sensor to adjust the anesthetic concentration in the induction chamber module; during the maintenance phase, control the flow rate of the precision injection pump in a closed loop based on the animal respiratory rate and / or tidal volume signal fed back by the integrated mask module to adjust the anesthetic concentration in the mask.

[0031] The present invention has the following beneficial effects: 1. Improved anesthesia efficiency and drug utilization: The electro-injection nebulizer delivery module adopts a dual nebulization mechanism combining a high-voltage electrostatic field and high-speed compressed air, which can stably generate fine anesthetic aerosols with a particle size range of 1μm-5μm. Droplets in this particle size range are more likely to penetrate and deposit in the alveolar region of experimental animals, thereby significantly improving the absorption efficiency of anesthetics in the lungs. Compared with the larger droplets (usually greater than 5μm) produced by traditional nebulization technology (such as ultrasonic nebulization), this device can achieve faster anesthesia induction and effectively reduce the unit consumption of anesthetics.

[0032] 2. Achieved precise and adaptive closed-loop control of anesthesia depth: The integrated mask module can monitor key vital signs parameters such as respiratory rate and / or tidal volume of the experimental target wearing the mask in real time. The main control unit receives these real-time physiological feedback signals and, based on a preset control algorithm (e.g., by comparing the deviation between the measured value and the target value), dynamically and precisely adjusts the output of anesthetic delivered to the integrated mask module during the maintenance anesthesia phase, forming a closed-loop control system. This closed-loop control system can automatically adjust the anesthetic supply according to the real-time physiological response of the individual animal, thereby overcoming the limitations of traditional open-loop control that relies on the operator's experience and judgment, significantly improving the stability and controllability of anesthesia depth, helping to maintain the stability of the animal's vital signs during the experiment, and reducing the risks caused by excessively deep or shallow anesthesia.

[0033] 3. Optimized experimental procedures and improved ease of operation and adaptability: The device employs a design where the induction chamber module and the integrated mask module can be switched to the same electro-injection nebulizer delivery module. During the induction phase, the induction chamber module allows animals to quickly and smoothly enter anesthesia in a closed, high-concentration aerosol environment. During the maintenance phase, the integrated mask module can be switched to provide precise control of continuous drug delivery. This phased, integrated design simplifies the operation process and avoids the risk of fluctuations in anesthesia depth caused by transferring animals to different devices after induction. Simultaneously, the adjustable integrated mask module, positioned on the animal anesthesia platform, can flexibly adapt to different animal sizes and head positions (such as supine and prone positions), ensuring a good airtight seal between the mask and the animal's mouth and nose, and guaranteeing the effectiveness and consistency of anesthetic gas delivery.

[0034] 4. Enhanced system functionality and intelligence: The main control unit, acting as the core coordinator, manages the electrical connections and signal interactions with the electro-injection nebulizer module, induction chamber module, and integrated mask module. It not only adjusts the anesthetic concentration within the induction chamber during the induction phase to achieve rapid and stable induction, but also implements closed-loop dynamic adjustment of anesthesia output based on physiological signals during the maintenance phase. This highly integrated control system organically combines efficient nebulization generation, phased anesthesia administration, real-time physiological monitoring, and adaptive feedback adjustment, forming an intelligent and integrated anesthesia work platform.

[0035] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0036] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the structure of a small animal anesthesia experimental device according to a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a preferred embodiment of the air-assisted coaxial electro-spray nozzle of the present invention; Figure 3 This is a schematic diagram of the structure of the annular perforated plate according to a preferred embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the induction chamber module according to a preferred embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the integrated face mask module according to a preferred embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of an animal anesthesia platform according to a preferred embodiment of the present invention.

[0037] Legend: 100. Electro-injected atomized drug delivery module; 101. Air-assisted coaxial electro-spray nozzle; 1011. Central liquid needle; 1013. Insulating sleeve; 1014. Annular air chamber; 1015. Annular perforated plate; 102. High-voltage electrostatic generator; 103. Precision injection pump; 104. Compressed air source; 106. Copper ring; 107. Terminal air chamber of the annular air circuit system; 200. Induction chamber module; 201. Housing; 202. Hinge; 203. Lock; 204. Top cover; 205. Annular air distribution pipe ; 206. Air distribution hole; 207. Concentration sensor; 300. Animal anesthesia platform; 301. Panel; 302. Base column; 303. Sliding clamp; 304. Slide rail; 305. Sliding bracket; 306. Ear clip; 400. Integrated mask module; 401. Mask body; 402. Main channel; 403. Sampling branch; 404. MEMS hot film flow sensor chip; 405. Nose support structure; 500. Main control unit; 600. Air path switching module; 700. Exhaust gas treatment device. Detailed Implementation

[0038] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0039] like Figure 1As shown, the small animal anesthesia experimental apparatus of this embodiment includes: an electro-injection nebulizer delivery module 100, used to form a high-voltage electrostatic field and use high-speed compressed air to perform secondary nebulization on the anesthetic droplets initially nebulized by the high-voltage electrostatic field to generate anesthetic aerosols with a particle size of 1μm-5μm and output them; an induction chamber module 200, which is switchably connected to the output end of the electro-injection nebulizer delivery module 100, used to contain the experimental target and enable the experimental target to quickly enter an anesthetized state in the anesthetic aerosol environment; and an animal anesthesia platform 300, located downstream of the induction chamber module 200, used to support and fix the experimental target. The experimental device for small animals integrates a specially designed electro-nebulized drug delivery module 100, a switchable induction chamber module 200 and an integrated mask module 400, an adjustable animal anesthesia platform 300, and a main control unit 500 with closed-loop control function. The integrated mask module 400 is adjustablely mounted on the animal anesthesia platform 300 and switchably connected to the output of the electro-nebulized drug delivery module 100, used to monitor the respiratory rate and / or tidal volume of the experimental target wearing the mask in real time. The main control unit 500 is electrically connected to the electro-nebulized drug delivery module 100, the induction chamber module 200 and the integrated mask module 400, used to adjust the anesthetic concentration in the induction chamber module 200 during the induction phase, or to dynamically adjust the output of anesthetic delivered to the integrated mask module 400 during the maintenance anesthesia phase. The electro-injection nebulizer delivery module 100 employs a dual nebulization mechanism combining a high-voltage electrostatic field and high-speed compressed air, which can stably generate fine anesthetic aerosols with a particle size range of 1μm-5μm. Droplets in this particle size range are more likely to penetrate and deposit in the alveolar region of experimental animals, thereby significantly improving the absorption efficiency of anesthetics in the lungs. Compared with the larger droplets (usually greater than 5μm) produced by traditional nebulization technologies (such as ultrasonic nebulization), this device can achieve faster anesthesia induction and effectively reduce the unit consumption of anesthetics. The integrated mask module 400 can monitor key vital signs parameters such as respiratory rate and / or tidal volume of the experimental target wearing the mask in real time. The main control unit 500 receives these real-time physiological feedback signals and, based on a preset control algorithm (e.g., by comparing the deviation between the measured value and the target value), dynamically and precisely adjusts the output of anesthetic delivered to the integrated mask module 400 during the maintenance anesthesia phase, forming a closed-loop control system. This closed-loop control system can automatically adjust the anesthetic supply according to the real-time physiological response of the individual animal, thereby overcoming the limitations of traditional open-loop control that relies on the operator's experience and judgment, significantly improving the stability and controllability of the depth of anesthesia, helping to maintain the stability of the animal's vital signs during the experiment, and reducing the risks caused by excessively deep or shallow anesthesia.The device employs a design where the induction chamber module 200 and the integrated mask module 400 can be switched to the same electro-injection nebulizer delivery module 100. During the induction phase, the induction chamber module 200 allows the animal to quickly and smoothly enter an anesthetized state in a closed, high-concentration aerosol environment. During the maintenance phase, the integrated mask module 400 can be switched to provide precise control over continuous drug delivery. This phased, integrated design simplifies the operation process and avoids the risk of fluctuations in the depth of anesthesia caused by transferring the animal to different devices after induction. Simultaneously, the integrated mask module 400, adjustablely positioned on the animal anesthesia platform 300, can flexibly adapt to the head position of experimental animals of different sizes and in different experimental positions (such as supine and prone positions), ensuring a good airtight seal between the mask and the animal's mouth and nose, and guaranteeing the effectiveness and consistency of anesthetic gas delivery. The main control unit 500, acting as the core coordinator, manages the electrical connections and signal interactions with the electro-nebulized drug delivery module 100, the induction chamber module 200, and the integrated mask module 400. It not only adjusts the anesthetic concentration within the induction chamber module 200 during the induction phase to achieve rapid and stable induction, but also implements closed-loop dynamic adjustment of anesthesia output based on physiological signals during the maintenance phase. This highly integrated control system organically combines efficient nebulization generation, phased anesthesia implementation, real-time physiological monitoring, and adaptive feedback adjustment, forming an intelligent and integrated anesthesia platform. This invention's small animal anesthesia experimental device, through efficient and precise nebulization, closed-loop physiological feedback control, and switchable phased induction-maintenance operation, and through modular integration and synergistic effects, systematically solves the technical problems of low drug utilization efficiency, inaccurate anesthesia depth control, cumbersome operation procedures, and poor adaptability in existing small animal inhalation anesthesia techniques. This enables faster, safer, more stable, and more convenient small animal inhalation anesthesia, providing a reliable experimental tool for life science research. Optionally, when the animal anesthesia platform 300 has an electrical control component, such as electric lifting, electric sliding, animal body temperature monitoring, heart rate monitoring, etc., the animal anesthesia platform 300 is electrically connected to the main control unit 500.

[0040] like Figure 1 and Figure 2As shown, in this embodiment, the output end of the electro-injected nebulizer delivery module 100 is configured as a gas path switching module 600. The first output end of the gas path switching module 600 is connected to the induction chamber module 200, and the second output end is connected to the integrated mask module 400. The gas path switching module 600 is used to selectively deliver the anesthetic aerosol generated by the electro-injected nebulizer delivery module 100 to either the induction chamber module 200 or the integrated mask module 400. By integrating the two core anesthesia stages of induction and maintenance into the same physical system, the anesthetic aerosol delivery path can be quickly and reliably switched between the "induction mode" (to the induction chamber module 200) and the "maintenance mode" (to the integrated mask module 400) by operating a single gas path switching module 600. This avoids the need to use two independent gas supply systems or perform complex pipeline disconnection and reconnection operations during the induction and maintenance stages, simplifies experimental preparation and process conversion steps, reduces the risk of gas path contamination or anesthesia interruption due to manual operation errors, and significantly improves the overall convenience and reliability of operation. In anesthesia practice, the transition from the induction phase to the maintenance phase is a critical point where the depth of anesthesia is prone to fluctuation. This invention allows the use of anesthetic aerosols with consistent particle size characteristics generated by the same electro-injection nebulizer delivery module 100, seamlessly serving both phases. Through the rapid switching of the gas path switching module 600, after the animal is transferred from the induction chamber to the anesthesia platform and puts on the integrated mask, it can immediately obtain a continuous supply of anesthetic gas from the same nebulizer source. This effectively avoids the sudden changes in the depth of anesthesia that may be caused by switching between different anesthetic gas sources, providing the animal with a smoother transition to anesthesia, helping to maintain stable vital signs, and improving the safety of the anesthesia process. The shared high-performance electro-injected nebulizer delivery module 100 supplies gas to both functional modules, avoiding the need for separate nebulizer generators for the induction chamber and maintenance mask. This not only simplifies the overall system structure and reduces hardware complexity and cost, but also ensures the consistency of the physicochemical properties (such as particle size distribution) of the anesthetic aerosols used in the induction and maintenance phases, thereby guaranteeing the predictability and repeatability of the anesthetic effect at different stages. At the same time, the centralized nebulizer source makes it easier to perform unified maintenance, calibration and control.

[0041] like Figure 1As shown, in this embodiment, the air path switching module 600 includes: a valve body having an air inlet and an air outlet; a valve core rotatably disposed within the valve body, with an internal airflow channel; a drive mechanism connected to the valve core for driving the valve core to rotate to different working positions; a position detection element for detecting the rotational position of the valve core and outputting an electrical signal; the air inlet of the valve body is used to connect to the air delivery pipeline of the electronically injected atomized drug delivery module 100, and the two air outlets of the valve body are respectively connected to the induction chamber module 200 and the integrated mask module 400. By setting a valve body with an air inlet and an air outlet, and a valve core with an internal airflow channel that can be rotatably set inside the valve body, a basic structure of a mechanical airflow distribution valve is formed. The drive mechanism drives the valve core to rotate to different angles, which allows the airflow channel inside the valve core to selectively connect the air inlet of the valve body with one of the air outlets, while physically blocking the connection with the other air outlet. This achieves clear and thorough physical isolation between the airflow channels, effectively preventing gas crosstalk between the induction chamber module 200 and the integrated mask module 400, ensuring that the anesthetic aerosol is accurately and leak-free delivered to the target module, and guaranteeing precise control of the anesthetic concentration. The drive mechanism allows the valve core's rotation to be precisely driven by external commands (such as electrical signals from the main control unit 500), replacing the traditional manual knob or tubing insertion / removal methods. This provides a foundation for remote or programmed automatic control of the switching between the induction and maintenance phases in the anesthesia process. The position detection element can detect and provide feedback on the valve core's rotational position (e.g., "induction position," "maintenance position," or "closed position") in real time and output this position status as an electrical signal. This position feedback signal can form a closed loop with the main control unit 500, enabling the system to confirm whether the gas path switching action has been accurately executed, increasing operational reliability and providing crucial information for the automated operation and status monitoring of the entire system. The gas path switching function is integrated into a compact valve body assembly and driven by an electric or pneumatic drive mechanism. This allows the module to be easily integrated into the equipment without requiring manual piping operations outside the equipment. The addition of a position detection element enables the system to sense the real-time position of the valve core. This helps to intuitively display the current gas path status (e.g., "supplying gas to the induction chamber" or "supplying gas to the mask") on the user interface (e.g., a touchscreen). This improves the user-friendliness of the human-machine interface and the intelligence of the system, simplifies the user's operation steps, and reduces the risk of experimental failure due to manual switching errors.

[0042] In this embodiment, a double O-ring seal is provided between the valve core and the valve body to ensure airtight isolation between the channels. The double O-rings form a series of double sealing barriers; when the sealing performance of the first sealing ring slightly decreases due to factors such as long-term use, wear, or installation tolerances, the second sealing ring can still provide an effective sealing effect. This redundant design significantly reduces the risk of gas leakage due to the failure of a single seal, ensuring that when the valve core is in either the "induction" or "maintenance" working position, the anesthetic aerosol can only flow through the preset target channel (induction chamber module 200 or integrated mask module 400), while completely blocking the airflow to non-target channels. This prevents crosstalk of anesthetic gas between channels that should not be connected, and is a key structural measure to ensure precise control of anesthetic concentration and avoid gas waste and environmental pollution.

[0043] In this embodiment, the valve core has an L-shaped channel structure. When the L-shaped channel structure is rotated to the first position, it connects the air inlet and the first air outlet. When it is rotated to the second position, it connects the air inlet and the second air outlet. The L-shaped channel is a simple and well-defined internal flow channel. When it is rotated to the first position, one end of the L-shaped channel is aligned with the air inlet of the valve body, and the other end is aligned with the first air outlet (e.g., connected to the outlet of the induction chamber module 200), thus forming a complete and continuous airflow path from the air inlet to the first air outlet. Similarly, when rotated to the second position, the channel connects the air inlet and the second air outlet (e.g., connected to the outlet of the integrated mask module 400). This "one position, one path" design mechanically ensures that in any working position, only one preset airflow path is connected. This mutual exclusion prevents the air inlet from being accidentally connected to two air outlets at the same time, or the possibility of crosstalk between the two output paths, ensuring the absolute clarity and reliability of the airflow switching logic. The two working positions (first position and second position) corresponding to the L-shaped channel structure are fixed and clearly defined, which facilitates the collaborative design with the drive mechanism (such as a stepper motor or rotary electromagnet) and position detection elements (such as a Hall sensor or photoelectric switch). The drive mechanism can easily and precisely drive the valve core and stop it at these two preset angles. The position detection elements can accurately identify and provide feedback on whether the valve core has accurately reached the preset position. This collaboration of "structure-drive-feedback" ensures that the air path switching state (whether it leads to the induction chamber or the mask) is not only guaranteed by the mechanical structure, but can also be monitored and confirmed by the control system in real time and accurately. This achieves a close integration of mechanical action and electrical control, improving the accuracy and automation level of the entire switching process.

[0044] In this embodiment, both the air inlet and outlet of the valve body are quick-connect female connectors. The quick-connect female connector of the valve body's air inlet mates with the quick-connect male connector at the end of the air delivery pipeline to achieve quick connection and disconnection. Quick-connect connectors are a mature tool-free connection technology. By standardizing the valve body interface to a quick-connect female connector and equipping the end of the external air delivery pipeline with a corresponding quick-connect male connector, operators can achieve an airtight and secure connection between the air tube and the valve body without any tools, simply by pushing in and locking. Conversely, the connection can be quickly disconnected by pressing or rotating the unlocking mechanism. This simplifies the disassembly and assembly process during initial installation of the anesthesia system, daily cleaning and disinfection, module replacement, or maintenance of the air delivery pipeline, significantly shortening operation time and reducing the potential for low equipment preparation efficiency due to complex and time-consuming connection operations.

[0045] In this embodiment, the drive mechanism is a manual knob, which has a position indicator arrow and a positioning feel mechanism. The position indicator arrow on the manual knob points directly to the corresponding position marking (such as "Induce", "Maintain", "Close") on the valve body or surrounding panel. When the operator rotates the knob, they can visually confirm the current position pointed to by the knob in real time, that is, the current working status of the gas path switching module 600, without relying on any electronic display or power supply. The indication result is clear and interference-resistant, providing the operator with the most intuitive and reliable means of status confirmation, effectively preventing misjudgment or misoperation caused by unclear status indication. The positioning tactile mechanism (such as a ratchet, ball bearings and recesses, or cam structure) provides clear mechanical feedback for the rotation of the manual knob. When the knob is rotated to the preset position (such as the first position or the second position), the positioning tactile mechanism will produce a clear "in place" feel (e.g., a clear "click" sound or a sudden change in resistance). This dual tactile and auditory feedback not only provides the operator with immediate confirmation of successful operation, but also precisely and mechanically locks the valve core at the preset correct angle, preventing the knob from deviating from the set position due to vibration or accidental contact. This ensures the alignment accuracy of the L-shaped channel structure with each air port of the valve body, thereby guaranteeing the accuracy and reliability of airflow path switching.

[0046] In this embodiment, the position detection element adopts a micro switch or a Hall sensor. The signal from the position detection element is connected to the main control unit 500 to control the start / stop or switching of the working mode of the electro-injected nebulized drug delivery module 100. The micro switch (mechanically triggered) or the Hall sensor (magnetically inductive) can convert the physical rotation position of the valve core (e.g., corresponding to the "induction" or "maintenance" position) into a clear, circuit-recognizable electrical signal (such as a switching signal or analog voltage signal). This electrical signal is connected to the main control unit 500, which means that the mechanical state (where it leads) of the gas path switching module 600 is converted and transmitted into data that the control system can directly read and process. This allows the main control unit 500 to obtain the current anesthetic gas delivery target (induction chamber module 200 or integrated mask module 400) in real time and accurately, providing a key status input for the automated logic control of the system. After receiving a signal from the position detection element, the main control unit 500 can execute preset control logic accordingly, such as controlling the start / stop or switching of the working mode of the electronically injected atomizing drug delivery module 100. When the gas path is detected to switch to the "induction" position, the main control unit 500 can automatically start the atomizing module and supply air to the induction chamber. When the switch to the "maintenance" position is detected, the atomization output is automatically switched to the mask passage, and the atomization parameters may be adjusted accordingly. This achieves electrical interlock between the gas path status and the core functional module (atomizing module). The system can be designed to allow or automatically start the corresponding atomization process only when the gas path is detected to have been correctly switched to a certain effective working position, thereby preventing invalid atomization or incorrect gas emission due to misoperation (such as the gas path not being connected in place), and improving the standardization and safety of operation. Compared to relying on operators to visually confirm the position of manual knobs, electrical signal feedback from microswitches or Hall sensors provides objective and definite status information that can be recorded by the system, eliminating potential misjudgments caused by human observation. Based on this signal, the main control unit 500 can dynamically and accurately display the current gas path status (such as "induction gas supply" or "maintenance gas supply") on the user interface and provide status indications or abnormal alarms. At the same time, this status signal can be recorded along with other data such as timestamps, providing a traceable status log for the experimental process, which is helpful for post-experiment analysis and problem troubleshooting.

[0047] like Figure 1 and Figure 2As shown, in this embodiment, the electro-injection nebulization drug delivery module 100 includes a gas-assisted coaxial electro-spray nozzle 101, a high-voltage electrostatic generator 102, a precision injection pump 103, and a compressed air source 104. The gas-assisted coaxial electro-spray nozzle 101 adopts a coaxial structure with internal liquid and external gas. The inner layer of the gas-assisted coaxial electro-spray nozzle 101 is connected to the precision injection pump 103, and the outer layer of the gas-assisted coaxial electro-spray nozzle 101 is connected to the compressed air source 104. The high-voltage electrostatic generator 102 is connected to the inner layer of the gas-assisted coaxial electro-spray nozzle 101 and delivers anesthetic liquid through the inner layer. The system generates a high-voltage electrostatic field at the outlet to initially atomize the anesthetic liquid (more specifically, the high-voltage electrostatic generator 102 is connected to the central liquid needle 1011 of the air-assisted coaxial electrospray nozzle 101, through which the anesthetic liquid is delivered and a high-voltage electrostatic field is formed at the tip of the central liquid needle 1011 to initially atomize the anesthetic liquid). At the same time, high-speed compressed air introduced into the outer layer is used to perform secondary atomization of the anesthetic droplets that have been initially atomized by the high-voltage electrostatic field, so as to generate anesthetic aerosols with a particle size of 1μm-5μm and output them. By delivering anesthetic liquid through the inner layer and applying high-voltage electrostatics, the high-voltage electrostatic field first generates Coulomb force on the liquid jet, overcoming its surface tension and achieving preliminary "electrostatic atomization." Then, the high-speed compressed air flow introduced into the outer layer exerts a strong shearing and breaking effect on the droplets formed by the preliminary atomization, performing "pneumatic secondary atomization." These two physical atomization mechanisms, electrostatic atomization and pneumatic atomization, work synergistically and mutually reinforce each other in the coaxial structure, enabling the efficient and stable generation of ultrafine anesthetic aerosols with a particle size range of 1μm-5μm. Droplets in this particle size range have excellent aerodynamic characteristics and can effectively penetrate and deposit in the alveolar region of experimental animals with the respiratory airflow, thereby significantly improving the absorption efficiency of anesthetics in the lungs and laying the foundation for rapid anesthesia induction and efficient drug utilization. The precision injection pump 103 can accurately and stably control the flow rate of anesthetic liquid delivered to the inner layer of the air-assisted coaxial electro-spray nozzle 101 per unit time, which directly determines the mass concentration of the nebulized output drug. The high-voltage electrostatic generator 102 can precisely adjust the intensity of the high-voltage electric field applied to the nebulization tip, affecting the effect of the initial nebulization and the initial charge state of the droplets. The compressed gas source 104 can adjust the gas pressure and flow rate supplied to the outer layer, affecting the aerodynamic conditions of the secondary nebulization and the particle size distribution of the final droplets. By coordinating the adjustment of the liquid flow rate, high voltage, and gas pressure, the key characteristics such as the particle size, concentration, and flow rate of the final generated anesthetic aerosol can be comprehensively controlled, thereby meeting the different needs of nebulization output for different stages of anesthesia (such as high-concentration rapid induction and low-concentration fine maintenance).The electrostatic and pneumatic atomization mechanisms are integrated into a single coaxial nozzle, resulting in a compact structure that reduces the need for complex external piping. The precision injection pump 103, high-voltage electrostatic generator 102, and compressed air source 104 are standard or modular components, facilitating integration, calibration, and control. Through the coaxial structure design, the anesthetic liquid is always confined within the inner tubing before atomization, preventing premixing with external compressed air and avoiding premature evaporation or condensation during delivery, thus ensuring the accuracy of drug delivery dosage. The entire module functions as a single unit, facilitating connection with the main control unit 500 to achieve digital setting and automated operation of atomization parameters, thereby improving the overall system integration and ease of operation.

[0048] like Figure 2As shown, in this embodiment, the air-assisted coaxial electro-spray nozzle 101 includes an annular air path system and a central liquid path system. The annular air path system is coaxially sleeved on the outside of the central liquid path system. The inner central liquid path system is connected to the precision injection pump 103, and the outer annular air path system is connected to the compressed air source 104. The high-voltage electrostatic generator 102 is connected to the central liquid path system, and delivers anesthetic liquid through the central liquid path system and forms a high-voltage electrostatic field at the outlet to perform preliminary atomization of the anesthetic liquid (more specifically, the high-voltage electrostatic generator 102 is connected to the central liquid needle 1011 of the central liquid path system, and delivers anesthetic liquid through the central liquid path system and forms a high-voltage electrostatic field at the tip of the central liquid needle 1011 to perform preliminary atomization of the anesthetic liquid). The end air chamber 107 of the annular air path system is used to form a gas-liquid mixing zone. The high-speed compressed air delivered by the annular air path system performs secondary atomization of the anesthetic droplets after preliminary atomization by the central liquid path system to generate anesthetic aerosol, and then pushes the anesthetic aerosol into the air delivery pipeline and outputs it. The central liquid path system and the annular gas path system adopt a coaxial but physically isolated structure. The inner central liquid path system is dedicated to delivering anesthetic liquid from the precision injection pump 103, while the outer annular gas path system is dedicated to delivering high-speed compressed air from the compressed air source 104. This internal and external isolation flow channel design ensures that the anesthetic liquid is always delivered independently within the central liquid path system before reaching the end air chamber 107 of the annular gas path system, without being pre-mixed with compressed air. This avoids problems such as pre-atomization, evaporation, or unstable delivery of the liquid due to airflow disturbance in the pipeline. At the same time, the high-voltage electrostatic generator 102 is connected to the central liquid path system, which can accurately and stably apply a high-voltage electrostatic field to the liquid jet within the central liquid path system without being directly electrically interfered with by the outer gas flow field (airflow within the annular gas path system), providing a stable and controllable high-voltage electric field environment for initial electrostatic atomization. The annular gas path system's terminal gas chamber 107 forms a specific gas-liquid mixing zone, providing an ordered space for two-stage atomization. The first-stage atomization occurs at the end of the central liquid path system, where the liquid overcomes surface tension under the action of a high-voltage electrostatic field, forming initially charged droplets or jets, thus completing electrostatic atomization. The second-stage atomization then occurs within the gas-liquid mixing zone of the annular gas path system's terminal gas chamber 107. The high-speed compressed air flow from the annular gas path system exerts strong shearing, stretching, and breaking effects on the droplet flow formed by the initial atomization (especially its periphery) within the mixing zone, achieving further aerodynamic secondary atomization. This ordered two-stage atomization process of "electrostatic breaking followed by aerodynamic refinement" achieves efficient synergy and coupling between electric field energy and gas kinetic energy, enabling more full utilization of energy to refine droplets, thereby efficiently and stably generating anesthetic aerosols with small particle sizes (1μm-5μm) and more uniform distribution.The coaxial structure allows the gas flow channel (annular gas path system) to surround and enclose the liquid flow channel (central liquid path system), resulting in a compact and symmetrical structure. This not only makes the internal flow field of the nozzle more stable and symmetrical, reducing the possibility of local eddies or aerosol deposition on the wall, but also makes the external dimensions of the nozzle smaller, facilitating installation and integration, and avoiding the structural complexity and alignment problems that may arise from parallel connection of multiple independent nozzles. Stable and independent delivery of material and gas is achieved through physically isolated flow channels, and the efficient two-stage energy coupling process of "electrostatic preliminary atomization" and "pneumatic secondary atomization" is completed in an orderly manner at the end of the annular gas path system's gas chamber 107. This not only ensures the stability of the medium delivery before atomization and the specificity of the electric field application, but also significantly improves atomization efficiency and effect through the synergistic effect of the two-stage atomization.

[0049] like Figure 2As shown, in this embodiment, the central fluid circuit system includes a central fluid needle 1011. The central fluid needle 1011 is made of medical-grade 316L stainless steel capillary tube with an inner diameter of 0.15mm-0.8mm and an outer diameter of 0.6mm-1.0mm. The tip cone angle of the central fluid needle 1011 is 30°-60°. The central fluid needle 1011 is wrapped with an insulating sleeve 1013, which is a PEEK micro tubing with a wall thickness of 0.2mm-0.5mm. The inlet end of the central fluid needle 1011 is connected to a precision injection pump 103 through a high-pressure isolation fluid circuit tube. The distance between the outlet end of the central fluid needle 1011 and the annular gas circuit outlet is 1.0cm-3.0cm. The central liquid needle 1011 uses a medical-grade 316L stainless steel capillary tube, which has excellent biocompatibility and chemical inertness. This ensures that no corrosion or harmful substances will be released during long-term contact with various anesthetic liquids, thus guaranteeing the purity of the drug solution and the reliability of the experiment, and solving the technical problem of potential metal ion contamination of anesthetics. The inner diameter of the central liquid needle 1011 is limited to 0.15mm-0.8mm, providing a suitable flow channel size for anesthetic liquids at micro-flow rates (such as when used with a precision syringe pump 103), which is conducive to forming a stable and continuous laminar flow or a stable jet, avoiding flow pulsation or interruption. The outer diameter is 0.6mm-1.0mm, achieving miniaturization of the structure while meeting the requirements of inner diameter and mechanical strength. The tip cone angle is 30°-60°, optimizing the liquid film morphology and electric field concentration at the needle tip. This is conducive to forming a stable Taylor cone under a high-voltage electrostatic field, providing an ideal liquid morphology starting point for electrostatic atomization, and avoiding the instability of the liquid flow caused by too small an angle or the dispersion of the electric field intensity caused by too large an angle. The insulating sleeve 1013 is made of PEEK micro tubing with a wall thickness of 0.2mm-0.5mm. PEEK material has extremely high insulation strength, mechanical strength, and chemical resistance. Encasing the central liquid needle 1011 within the insulating sleeve 1013 achieves reliable electrical isolation between the central liquid needle 1011 and the external environment, preventing high-voltage breakdown or leakage, ensuring electrical safety on the low-pressure side of the system (such as the precision injection pump 103), and solving the technical problem of high-voltage circuits interfering with or harming low-voltage control circuits. The specific wall thickness ensures sufficient insulation and mechanical strength while maintaining the compactness of the component, facilitating integration. The insulating sleeve 1013 provides coaxial alignment and physical support for the internal central liquid needle 1011, ensuring its outlet end is accurately and stably positioned in the annular gas path. The inlet end of the central liquid needle 1011 is connected to the precision injection pump 103 via a high-pressure isolation liquid line pipe. This high-pressure isolation liquid line pipe further ensures fluid connectivity and electrical isolation between the high-pressure area and the precision injection pump 103, forming a double safety isolation barrier.The distance between the liquid outlet of the central liquid needle 1011 and the outlet of the annular gas path is set to 1.0cm-3.0cm, reserving a necessary "electrostatic field zone" for the initial electrostatic atomization process at the tip of the central liquid needle 1011, free from direct impact from external airflow. The liquid flow is mainly affected by the high-voltage electrostatic field, which can fully charge it and form initial atomization (generating initial charged droplets or jets). This distance ensures that the initial atomization products have completed the first stage of electrostatic fragmentation before entering the high-speed airflow shearing zone at the annular gas path outlet. This allows the subsequent pneumatic secondary atomization to proceed under better starting conditions (facing already charged and initially fragmented micro-droplets, rather than a continuous liquid column), improving the synergistic efficiency of the two-stage atomization (electrostatic atomization and pneumatic atomization) and the uniformity of the final droplet size. Too short a distance may lead to insufficient electrostatic atomization, i.e., interference from airflow. Too long a distance may cause the initial droplets to condense or deposit before reaching the high-speed airflow zone. By selecting medical-grade materials for the central liquid needle 1011, specifying its inner and outer diameters and cone angle, setting the PEEK material and wall thickness for the insulating sleeve 1013, and configuring the high-voltage isolation connection at the inlet and the specific spacing at the outlet, the stability and biosafety issues of micro-delivery of anesthetics, the electrical isolation and safety issues of the high-voltage electrostatic field, and the orderly connection and efficient coordination of electrostatic atomization and pneumatic atomization were synergistically resolved. This ensures that the anesthetic liquid can be delivered to the atomization zone in a stable and controlled state, and effectively initiate electrostatic atomization within a protected electric field region, laying a reliable structural foundation for the subsequent generation of fine anesthetic aerosols with uniform particle size ranging from 1μm to 5μm. Optionally, for mice (adult weight 18g-40g), the inner diameter of the central liquid needle 1011 is 0.15mm-0.3mm. Optionally, for rats (adult weight 200g-500g, males over 600g), the inner diameter of the central fluid needle 1011 is 0.3mm-0.8mm.

[0050] like Figure 2 and Figure 3As shown, in this embodiment, the annular air circuit system includes an annular air chamber 1014, which is a PEEK micro-tube with an annular gap width of 0.1mm-0.3mm and an annular diameter of 1.5mm-3.0mm. The air inlet of the annular air chamber 1014 is connected to a compressed air source 104, and a copper ring 106 is provided on the outer wall of the air outlet of the annular air chamber 1014. The copper ring 106 is coaxially arranged with the annular air chamber 1014, and the diameter of the copper ring 106 is 2mm-5mm. An airflow rectification structure is provided inside the annular air chamber 1014. The airflow rectification structure adopts an annular perforated plate 1015. Multiple axial through holes are evenly distributed along the circumference of the annular perforated plate 1015. The diameter of the axial through holes is 0.2mm-0.5mm, and the plate thickness is 0.3mm-1.0mm. The annular gas chamber 1014 is made of PEEK microtubes, which possess excellent mechanical strength, dimensional stability, and chemical corrosion resistance. It can withstand the pressure of compressed gas and maintain geometric stability over a long period, preventing deformation from affecting the uniformity of the annular gap. Its insulation properties also ensure the isolation of the gas path from the external circuitry. The annular gap width is limited to 0.1mm-0.3mm. This narrow and uniform annular gap can generate a high airflow velocity at a given gas flow rate, providing sufficient shear force for secondary atomization. The annular diameter is 1.5mm-3.0mm. This size range ensures that the annular airflow can effectively coaxially wrap around the central liquid path system, forming a stable gas-liquid two-phase flow interface. Copper rings 106 with a diameter of 2mm-5mm are coaxially arranged on the outer wall of the outlet of the annular gas chamber 1014. As a good conductor, the coaxial arrangement of the copper rings 106 helps to balance the electric field distribution near the outlet. During the high-voltage electrostatic atomization process, the tip of the central liquid needle 1011 is at a high potential, while there may be an uneven electric field distribution near the outlet of the annular gas cavity 1014. The presence of the copper ring 106 can act as an equipotential body, improving the uniformity of the electric field distribution in the gas-liquid mixing zone, which is beneficial to stabilizing the electrostatic atomization process, preventing atomization instability or abnormal discharge caused by electric field distortion, and synergistically improving the stability of the overall atomization field. An annular porous plate 1015 is installed inside the annular air cavity 1014 as an airflow rectification structure. Multiple axial through holes with a diameter of 0.2mm-0.5mm are evenly distributed along the circumference of the porous plate, and the plate thickness is 0.3mm-1.0mm. The airflow from the compressed air source 104 may be turbulent, pulsating, or non-uniform. When the airflow passes through this annular porous plate 1015, it is divided, dispersed, and recombined by the numerous evenly distributed small through holes. This can effectively destroy large-scale eddies and adjust the non-uniform incoming flow into multiple parallel and stable micro airflow streams, which significantly improves the uniformity, laminarization degree, and directional consistency of the annular airflow flowing out of the annular air cavity 1014.Uniform and stable annular high-speed airflow is a key prerequisite for effective and consistent pneumatic secondary atomization. It ensures that uniform and continuous shear force is applied to the initial atomization products (charged droplets / jet) delivered by the central liquid needle 1011 on the entire circumference of the annular outlet, thereby producing a final aerosol (1μm-5μm) with a more concentrated and uniform particle size distribution. If the airflow is not uniform, the droplets will experience different shear forces, which will lead to a wider droplet size distribution and affect the consistency of anesthetic deposition efficiency. By employing PEEK material and defining the annular gap and diameter dimensions, a stable and high-speed annular airflow channel was constructed. The addition of a coaxial copper ring 106 optimized the stability of the electric field distribution in the atomization region. The built-in annular porous plate 1015 rectification structure with specific parameters effectively improved the uniformity and stability of the working airflow. This solved the key technical problem of how to provide a uniform, stable, high-speed annular shear airflow in a favorable electric field environment for secondary atomization in the air-assisted coaxial electro-spray nozzle 101, thus providing reliable aerodynamic conditions for the final generation of uniformly sized and controllable ultrafine anesthetic aerosols.

[0051] like Figure 4As shown, in this embodiment, the induction chamber module 200 includes a housing 201; the top of the housing 201 is configured as a top cover 204 sealed to the top opening by a hinge 202, a latch 203, and a sealing strip, and the top cover 204 is provided with an air outlet; the bottom of the housing 201 is provided with an annular air distribution pipe 205 and an air inlet, the air inlet being connected to the annular air distribution pipe 205, the annular air distribution pipe 205 being densely covered with air distribution holes 206, so that the gas enters through the air inlet and rises evenly through the air distribution holes 206 of the annular air distribution pipe 205; the diameter of the air distribution holes 206 is 0.3mm-0.8mm, the hole spacing is 5mm-15mm, and the opening direction of the air distribution holes 206 forms an angle of 30°-60° with the horizontal plane, so that the airflow forms a uniform dispersion inside the induction chamber module 200. Optionally, the housing 201 is a transparent housing with a length of 300mm, a width of 20mm, and a height of 20mm. Optionally, the housing 201 is made of high-transmittance acrylic material with a thickness of 10mm. Optionally, the air inlet and the annular air distribution pipe 205 are connected by a flexible connecting pipe, one end of which is connected to an air inlet connector inserted through the cabin wall, and the other end is connected to the air inlet end of the annular air distribution pipe 205. Optionally, the air inlet and the annular air distribution pipe 205 are an integral structure, that is, the bottom of the cabin is integrally formed with an annular air passage and an air inlet channel communicating with it, and the opening of the air inlet channel is located on the outside of the cabin wall. Optionally, a concentration sensor 207 (anesthetic concentration sensor) is installed inside the induction chamber module 200. The concentration sensor 207 inside the chamber monitors in real time and performs closed-loop control to ensure a smooth induction process without overshoot. The annular gas distribution pipe 205, located at the bottom of the chamber 201, with its densely packed gas distribution holes 206, specific hole diameters (0.3mm-0.8mm), hole spacing (5mm-15mm), and opening direction (at an angle of 30°-60° with the horizontal plane), works together to form a highly efficient gas distributor. After the anesthetic aerosol from the air inlet enters the annular gas distribution pipe 205, it is divided into numerous small, upward-sloping air jets by the many holes. The specific hole diameter and spacing ensure the uniformity of airflow distribution, while the inclined opening direction prevents the airflow from being vertically upward, instead creating swirling or more complex convection within the chamber. This greatly promotes the rapid and uniform mixing and dispersion of the aerosol within the limited space, effectively avoiding airflow short-circuiting or localized excessively high / low concentrations. The air outlet on the top cover 204, combined with the uniform gas distribution at the bottom, forms a bottom-to-top, overall gas replacement path, facilitating the rapid filling of the chamber with fresh anesthetic gas and the replacement of waste gas, thereby achieving rapid construction of the anesthesia induction environment.The enclosure 201 is made of transparent material (such as high-transmittance acrylic) and has set observation dimensions (e.g., 300mm long, 20mm wide, and 20mm high), allowing the operator to directly and clearly observe the anesthesia induction process and behavioral status of the animals inside the enclosure from the outside, facilitating timely judgment. The top cover 204 is connected to the top opening of the enclosure 201 via a hinge 202, a latch 203, and a sealing strip. This design enables the top cover 204 to be opened and closed quickly and reliably sealed. The hinge 202 facilitates the flipping of the top cover 204 to insert or remove animals; the latch 203 ensures a tight fit when closed; and the sealing strip ensures airtightness when closed, preventing leakage of anesthetic gas, maintaining an effective concentration inside the enclosure, and protecting the operating environment. This design balances ease of operation, intuitive observation, and process safety. Two options are available for connecting the annular gas distribution pipe 205 to the air inlet: a flexible connecting pipe or an integrated structure. A flexible connecting pipe connection can buffer vibration, accommodate installation tolerances, and facilitate the installation and maintenance of the annular gas distribution pipe 205. The integrated structure offers higher structural integrity and sealing reliability, avoiding potential leakage points at the joints. A concentration sensor 207 is installed inside the chamber and connected to the control system, forming an optional environmental concentration monitoring and feedback control loop. This loop can monitor the actual concentration of anesthetic aerosols inside the chamber in real time and form a closed loop with the main control unit 500 and the electro-injected nebulizer delivery module 100, dynamically adjusting the nebulization output to ensure the chamber concentration quickly reaches and stabilizes at the preset value, preventing overshoot and achieving a smoother, more controllable anesthesia induction process, thus improving safety, comfort, and efficiency during the induction phase. The induction chamber module 200, through a specific gas distribution design of the bottom annular gas distribution tube 205, achieves rapid and uniform spatial diffusion of anesthetic aerosols within the induction chamber, providing animals with a consistent and efficient induction environment. The transparent box 201 and convenient sealing top cover 204 ensure visibility, convenience, and airtight safety during operation. Optional flexible connecting tubes or integrated connections and closed-loop concentration control further enhance the structural adaptability and precise controllability of the induction process, providing small animals with an efficient, safe, visible, and controllable closed-loop anesthesia induction space. Optionally, the bottom of the box 201 has a clamping structure, with the annular gas distribution tube 205 and air inlet both located within the clamping structure; the air inlet enters from the clamping structure and connects to the annular gas distribution tube 205 via the air inlet, as shown. Figure 4 As shown. Optionally, for mice, the volume of the chamber 201 is 1.5L-2.5L. Optionally, for rats, the volume of the chamber 201 is 5L-8L.

[0052] In this embodiment, the induction chamber module 200 also includes a concentration sensor 207. The concentration sensor 207 is installed at the center of the inner wall of the housing 201 via a quick-connect sealing connector and is electrically connected to the main control unit 500. The main control unit 500 adjusts the precision injection pump 103 of the electro-injection nebulizer module 100 through a PID control algorithm based on the feedback signal from the concentration sensor 207. The main control unit 500 has preset PID parameters for different housing volumes 201 to facilitate automatic matching.

[0053] In this embodiment, the exhaust port of the housing 201 is connected to a waste gas treatment device 700 to adsorb anesthetics in the discharged gas. A negative pressure sensor is installed on the pipeline between the exhaust port and the waste gas treatment device 700 to monitor pipeline patency. The waste gas treatment device 700 includes a replaceable activated carbon filter canister filled with an activated carbon layer. Both the inlet and outlet ends of the activated carbon filter canister are equipped with quick-connect fittings. A one-way valve is installed at least at one of the inlet, outlet, or the inlet and outlet ends of the activated carbon filter canister to prevent gas backflow. Optionally, the activated carbon layer is made of granular activated carbon. The waste gas treatment device 700 containing the activated carbon layer is connected to the exhaust port of the housing 201 to adsorb and remove anesthetic components from the discharged gas. Activated carbon has a well-developed porous structure and a large specific surface area, which can efficiently capture volatile anesthetic molecules through physical adsorption, effectively preventing the direct discharge of anesthetic waste gas into the laboratory environment, protecting the occupational health of operators, reducing environmental pollution, and complying with laboratory safety and environmental protection regulations. A negative pressure sensor is installed on the pipeline between the air outlet and the exhaust gas treatment device 700 to monitor the pressure status within the pipeline. During normal system operation, the pipeline typically maintains a certain negative pressure (relative to atmospheric pressure) due to the possible presence of an exhaust fan or airflow downstream. The negative pressure sensor can monitor this pressure value in real time. If insufficient or absent negative pressure is detected (e.g., due to pipeline detachment, blockage, or abnormally increased air intake resistance of the exhaust gas treatment device 700), it can be determined that the pipeline is not clear or the system is abnormal. The main control unit 500 can issue an alarm based on this signal to prompt the operator to check, thereby preventing the risk of excessive accumulation of anesthetic gas in the induction chamber module 200 or leakage into the environment due to poor exhaust gas discharge, thus improving the safety of the system. The activated carbon filter canister features a replaceable design and a quick-connect fitting, allowing operators to easily remove the old filter canister and insert a new one without tools once the activated carbon is saturated. This simplifies maintenance and ensures continuous waste gas treatment capacity. One-way valves are installed at the inlet, outlet, or between the inlet and outlet of the activated carbon filter canister to prevent backflow. When the system stops operating or the downstream exhaust system is shut down, the one-way valves prevent ambient air or gas from downstream pipelines from flowing back into the filter canister and induction chamber. This avoids potential contamination, premature moisture absorption and failure of the activated carbon, and prevents unexpected changes in pressure or gas composition within the induction chamber module 200 caused by backflow, ensuring a unidirectional waste gas path and a clean system.

[0054] In this embodiment, the activated carbon filter canister is transparent to facilitate observation of its internal state. The canister also contains a pre-filter layer and a post-filter layer, located upstream and downstream of the activated carbon layer, respectively. The transparent canister allows operators to directly observe the physical state of the activated carbon layer and other filter layers, such as color changes, adsorption levels, and the presence of significant pollutants or moisture accumulation. This provides a simple and direct qualitative assessment method that does not rely on electronic sensors. When the activated carbon color darkens significantly or the pre-filter layer becomes noticeably dirty, it is intuitively apparent that the filter canister may be nearing adsorption saturation or requires maintenance. This provides timely visual warnings for filter replacement, helping to prevent continued use after a significant decline in filtration efficiency, thus ensuring the continuity of waste gas treatment effectiveness. A pre-filter cotton layer is installed upstream of the activated carbon layer to perform pre-filtering of the exhaust gas entering the filter tank. The pre-filter cotton layer can intercept and adsorb larger particles, small droplets formed by water vapor condensation, or impurities such as animal hair that may be carried in the exhaust gas. This prevents these larger particles from directly covering and clogging the surface micropores of the activated carbon, protecting the effective adsorption surface area of ​​the activated carbon layer, extending its service life, and ensuring that the airflow can pass through the activated carbon layer evenly. A post-filter cotton layer is installed downstream of the activated carbon layer to perform post-filtering of the gas after adsorption by the activated carbon. This can capture extremely fine particles that may escape from the activated carbon layer or a small amount of dust that may be generated by the activated carbon itself, ensuring the cleanliness of the final exhaust gas and further reducing any possible particulate matter emissions. The pre-filter and post-filter cotton layers are composed of fibrous materials with a certain thickness and bulkiness. Besides their filtration function, they structurally encapsulate, fix, and buffer the granular activated carbon layer, preventing the activated carbon particles from shifting or generating excessive dust due to friction during transportation, installation, or use, or from forming uneven voids (channeling). The presence of the cotton layers helps the airflow pass more evenly across the entire cross-section of the filter tank, improving the utilization rate of activated carbon and maintaining the stability and integrity of the internal structure of the filter tank. The transparent tank and the upstream and downstream cotton layers provide direct and visual monitoring of the filter tank's operating status (especially the degree of activated carbon adsorption), simplifying maintenance decisions. The tiered design of the pre-filter and post-filter cotton layers achieves multi-stage purification of the exhaust gas, protecting the core activated carbon adsorption layer, extending its lifespan, and improving the overall cleanliness of the final exhaust gas. The cotton layer structure also fixes the activated carbon and optimizes airflow distribution. These features synergistically enhance the maintainability, filtration efficiency, and operational reliability of the exhaust gas treatment device 700.

[0055] In this embodiment, the output end of the induction chamber module 200 and / or the output end of the integrated mask module 400 are connected to the waste gas collection module via a pipeline with a one-way valve. The mixing chamber outlet of the waste gas collection module is connected to the waste gas treatment device 700. By setting up a common waste gas collection module, waste gases generated from different anesthesia work units (induction chamber module 200, integrated mask module 400) can be collected into the same main pipeline and finally connected to a unified waste gas treatment device 700 for treatment. This eliminates the need for a separate complete waste gas treatment device 700 (including pipelines, filter canisters, and possibly fans) for each waste gas source (induction chamber, mask), simplifying the external pipeline layout of the system, reducing the number of hardware components, lowering the overall cost and equipment space occupied, and centralizing the maintenance points for waste gas treatment (such as replacing filter canisters), thereby improving the system's integration and maintenance convenience. A one-way valve is installed on the pipeline connecting the output of the induction chamber module 200 and the integrated mask module 400 to the exhaust gas collection module. The characteristic of the one-way valve is that it only allows gas to flow in one direction (from the exhaust gas source to the exhaust gas collection module) and prevents reverse flow. This can prevent cross-contamination. When a unit (such as the induction chamber) is emitting high-concentration exhaust gas, the one-way valve can effectively prevent this exhaust gas from flowing back through the collection module into the pipeline of another unit (such as the integrated mask module 400) that may be in a non-working or low-pressure state at the time, thus avoiding the diffusion of anesthetic gas in an unwanted path. It can also prevent gas backflow. When the system operates intermittently, the airflow is unstable, or the downstream exhaust gas treatment device 700 generates changes in suction force, the one-way valve can prevent gas from flowing back from the collection module or the main pipe into each exhaust gas source branch, thereby maintaining the independence of gas composition and pressure inside each anesthesia unit (induction chamber or mask cavity) and ensuring the stability and controllability of the anesthesia environment. The design of the exhaust gas collection module and its mixing chamber provides a buffer and mixing space for the convergence of multiple exhaust gases, which helps to smooth out instantaneous flow fluctuations that may come from different branches, making the total airflow after convergence more stable. This is beneficial to the stable and efficient operation of downstream exhaust gas treatment devices 700 (such as activated carbon filter tanks and exhaust fans). The pipeline design with one-way valves ensures that even when a certain exhaust gas does not generate airflow temporarily (such as when the mask module is not used during the induction phase), its branch will not become a bypass leak point or backflow inlet for exhaust gas emissions from other branches, thus maintaining the effectiveness and controllability of the entire exhaust gas emission system.

[0056] like Figure 5As shown, in this embodiment, the integrated mask module 400 includes a mask body 401, which has independent air inlets and outlets. Both the air inlet and outlet are equipped with one-way valves to allow gas to enter through the air inlet and exit through the air outlet. The air outlet of the mask body 401 is configured as a split-flow airway structure, which includes a main flow channel 402 and a sampling branch 403. The cross-sectional area of ​​the branch is 15% of the cross-sectional area of ​​the main flow channel 402. The inlet end of the main flow channel 402 and the inlet end of the sampling branch 403 meet at the inlet end of the air outlet, and the outlet end of the main flow channel 402 and the outlet end of the sampling branch 403 meet at the outlet end of the air outlet. The air outlet is connected to the waste gas treatment device 700 through a waste gas hose. The top of the inner wall of the mask body 401 is provided with a nose support structure 405, which is used to cooperate with the bridge of the nose of the experimental target to limit the depth of the mouth and nose insertion and make the tip of the nose face the split point of the main flow channel 402 and the sampling branch 403. Optionally, the ends of the exhaust hoses are connected via male connectors (quick-connect female and quick-connect male). One-way valves are installed in both the inlet and outlet of the enclosure 401, creating a unidirectional gas flow path. The inlet one-way valve only allows fresh anesthetic gas to enter the enclosure 401 from the external pipeline, preventing gas from flowing back into the intake system. The outlet one-way valve only allows exhaled waste gas and excess anesthetic gas from the animal to be discharged from the enclosure 401 into the exhaust hose, preventing waste gas or ambient air from flowing back into the enclosure 401. This dual one-way valve design ensures that gas flows strictly in the predetermined direction of "inlet to outlet" within the enclosure 401, effectively preventing the retention and re-inhalation of exhaled waste gas within the enclosure 401, or the reciprocating mixing of airflow caused by respiratory movements. This ensures the stability and freshness of the anesthetic concentration in the animal's inhaled gas and improves the efficiency of waste gas discharge. The split-flow airway structure (including the main flow channel 402 and the sampling branch 403) is a core design integrating respiratory monitoring and anesthetic gas delivery. The main flow channel 402 is the primary passage for exhalation through the animal's mouth and nose. The sampling branch 403 and the main flow channel 402 converge at the inlet end of the outlet, and simultaneously converge at the outlet end of the outlet, forming a parallel airway branch with the main flow channel 402. The airflow cross-sectional area of ​​the sampling branch 403 is precisely designed to be 15% of the cross-sectional area of ​​the main flow channel 402. This specific ratio achieves gas splitting, allowing most of the gas to pass through the main flow channel. Exhaled gas (which accounts for the majority of the total flow) is exhaled directly through the main flow channel 402; simultaneously, a small portion of the airflow (approximately 15% of the total flow) is diverted in a constant proportion to the sampling branch 403; this sampling branch 403 is dedicated to connecting a high-sensitivity flow or gas sensor (such as a MEMS thermal film flow sensor), providing a representative and moderately flowable sample airflow for real-time and accurate monitoring of the animal's respiratory rate and tidal volume; this integrated design eliminates the need for an additional independent sampling probe in front of the animal's mouth and nose, simplifies the structure, avoids interference, and ensures the authenticity of the monitoring signal.The nose support structure 405, located at the top of the inner wall of the mask 401, conforms to the contour of the experimental animal's nasal bridge. The nose support limits the depth to which the animal's mouth and nose can penetrate the mask 401, preventing airway obstruction due to over-insertion or gas leakage due to insufficient insertion. This ensures that, when correctly worn, the animal's nose tip is directly aligned with the branching point between the main flow channel 402 and the sampling branch 403, allowing the animal's respiratory airflow to directly and effectively act on the branching point. This guarantees efficient inhalation of anesthetic gas and ensures that the sampling branch 403 can collect the most representative respiratory sample, thereby ensuring the accuracy and consistency of the anesthetic effect and monitoring data. The exhaust hose uses a quick-connect male connector with a corresponding quick-connect female connector, allowing the exhaust pipe of the mask module to be quickly and reliably connected to the downstream exhaust collection module or treatment device. This simplifies the pipe connection operation when switching the anesthesia system from induction to the maintenance phase, enabling rapid deployment. Optionally, an arc-shaped retaining wall is also provided between the main road 402 and the sampling branch road 403 to isolate the main road 402 from the sampling branch road 403.

[0057] like Figure 5As shown, in this embodiment, the housing 401 also includes: a MEMS hot-film flow sensor chip 404, disposed within the sampling branch 403, for detecting the flow rate and direction of respiratory airflow; a sensor holder, for fixing the MEMS hot-film flow sensor chip 404 onto the sampling branch 403 and forming a sampling cavity; a signal conditioning circuit board, electrically connected to the MEMS hot-film flow sensor chip 404, for amplifying and filtering the sensor signal; a composite transmission cable, which is a multi-core shielded signal cable, with its first end connected to a miniature aviation plug of the housing 401 and its second end connected to the main control unit 500; and the main control unit 500, which is connected to the composite transmission cable and the electro-injected atomized drug delivery module 100, and includes an isolation sampling circuit, a control output interface, and a digital signal processor. The MEMS hot-film flow sensor chip 404 is directly placed inside the sampling branch 403, allowing it to directly contact and measure the respiratory sample airflow passing through the branch. MEMS technology enables the sensor to be miniaturized, highly sensitive, and fast-responding, accurately detecting subtle changes in the velocity and direction of the respiratory airflow (inhalation and exhalation). The sensor mount fixes it and forms a defined sampling cavity, ensuring that the airflow flows through the sensor's sensitive area in a stable state, improving the accuracy and repeatability of the measurement. This design, which integrates the miniature sensor in situ into the mask's sampling airway, achieves direct, non-invasive, and real-time capture of respiratory signals, avoiding signal delay and attenuation caused by long sampling tubes, and providing high-quality raw signals for real-time closed-loop control. The signal conditioning circuit board is electrically connected to the MEMS hot-film flow sensor chip 404, which can pre-amplify and filter the original weak electrical signal output by the sensor. Amplification increases the signal amplitude and enhances the ability to resist transmission interference. Filtering can effectively suppress high-frequency electrical noise and possible power frequency interference in the environment. The processed signal is transmitted over long distances through the multi-core shielded signal line in the composite transmission cable. The shielding layer can prevent external electromagnetic fields from interfering with sensitive bioelectric signals.The composite transmission cable connects to the miniature aviation connector on the housing 401. The conditioned signal is led out through the miniature aviation connector, which is waterproof, enabling fast and reliable connection and disconnection of the sensor signal. The second end of the composite transmission cable connects to the main control unit 500, forming a signal transmission path from the sensor to the control center. The isolation sampling circuit inside the main control unit 500 is used to safely and accurately acquire sensor signals from the composite cable. Electrical signal isolation further prevents interference from high-voltage or high-power circuits to weak signal circuits. The digital signal processor is responsible for running control algorithms (such as PID algorithms) to process and analyze the acquired respiratory signals (frequency, tidal volume) in real time. The control output interface outputs control commands based on the processing results to drive the electro-injection nebulizer delivery module 100 (such as adjusting the flow rate of the injection pump or the voltage of the high-voltage power supply). A complete closed-loop feedback control link is established from respiratory signal detection, signal conditioning and transmission, signal acquisition and processing, to control command generation and output. The main control unit 500, as the core, compares real-time monitored animal respiratory parameters (such as respiratory rate below a safety threshold) with preset target values. It calculates the adjustment amount through a control algorithm in a digital signal processor and dynamically and precisely adjusts the output parameters of the electro-injection nebulizer module 100 via the control output interface. For example, when respiratory depression (too low frequency) is detected, the anesthetic output is automatically reduced; when anesthesia is too shallow, the output is increased. This makes the anesthetic supply no longer fixed or manually adjustable, but dynamically adjusted adaptively with millisecond-level response based on the animal's real-time physiological state. Integrating MEMS sensors, signal conditioning, composite cables, and the main control unit 500, a complete and reliable closed-loop feedback control system is constructed, from high-fidelity in-situ acquisition, anti-interference transmission and processing of respiratory signals to real-time and precise adjustment of the anesthesia nebulizer module based on algorithmic decision-making. This deeply integrates physiological monitoring and anesthesia control, realizing the transformation of anesthesia depth from "experience-based open-loop control" to "signal feedback closed-loop control," thereby improving the accuracy, safety, stability, and automation level of maintaining anesthesia. Optionally, as... Figure 5 As shown, Figure 5The headband has a pair of fastening buckles symmetrically positioned on both sides of the cover 401, corresponding to the area behind the animal's ears. The two ends of the elastic headband are connected to the fastening buckles via adjusting buckles, and then to the headband at both ends. Optionally, for mice, the inner volume of the cover 401 is 2mL-4mL, the inner diameter of the air inlet is 2mm-3mm, and the inner diameter of the air outlet is 2.3mm-3.0mm. Optionally, for rats, the inner volume of the cover 401 is 8mL-12mL, the inner diameter of the air inlet is 3mm-4mm, and the inner diameter of the air outlet is 3.5mm-4.5mm. Optionally, the air inlet of the cover 401 (located above the air outlet) is positioned at the top front of the cover 401, horizontally directly above the tip of the nose, vertically 5mm-8mm from the highest point of the nose tip, with its axis forming a downward angle of 30°-45° with the horizontal plane. Optionally, the air outlet of the cover 401 (including the main channel 402 and the sampling branch 403) is located at the bottom front of the cover 401, with the opening corresponding to 3mm-5mm below the animal's lower jaw, and the axis vertically downward or slightly tilted backward. Optionally, the inner wall of the cover 401 is provided with a nose support structure 405 for securing the animal's nose bridge, so that the tip of the nose is precisely located within the airflow impact zone 2mm-3mm downstream of the air inlet. Optionally, the air outlet is provided with a main channel 402 and a sampling branch 403, and the MEMS hot-film flow sensor chip 404 is located in the sampling branch 403.

[0058] like Figure 6As shown, the animal anesthesia platform 300 is used to fix the experimental target (animal) and includes a panel 301, a base column 302, a sliding clamp 303, a slide rail 304, a sliding bracket 305, and an ear clip 306. Slide rails 304 are respectively arranged corresponding to the head and limbs of the experimental target (animal). Sliding brackets 305 are slidably arranged on the slide rails 304 at the head position to achieve sliding control and fixation of the sliding brackets 305 (fixed positioning after sliding adjustment using springs, pins, springs, ball bearings, etc.). The head of the experimental target (animal) is fixed and positioned using the relatively arranged sliding brackets 305 and the ear clips 306 on the sliding brackets 305 to ensure a close fit between the integrated mask module 400 and the animal's head. Optionally, the ear clip 306 is a telescopic rod or a threaded sleeve rod with a clamping part at the end, such as a rounded, spindle-shaped ear clip. Sliding clamps 303 are evenly distributed on the slide rails 304 at the limb positions to achieve sliding control and fixation of the sliding clamps 303 (fixed positioning after sliding adjustment using springs, pins, springs, ball bearings, etc.). The sliding clamps 303 are used to clamp and fix the limbs of the experimental target (animal). The bottom of the panel 301 is supported by the base column 302. Optionally, the base column 302 is a threaded sleeve, telescopic rod, cylinder, or hydraulic cylinder to facilitate the lifting and lowering control of the panel 301. Optionally, the dimensions of the panel 301 of the animal anesthesia platform 300 are 300mm × 250mm × 50mm. The animal anesthesia platform 300 provides the ability to finely adjust the spatial position (especially the height, front-back, and left-right positions) of the integrated mask module 400 with multiple degrees of freedom. Operators can easily and smoothly move and match the integrated mask module 400 by coordinating the control of the base column 302, sliding clamp 303, and sliding bracket 305. This allows the air inlet and outlet of the integrated mask module 400 to be precisely aligned with and adapted to the mouth and nose positions of experimental animals of different body sizes and positions (supine, prone, and lateral). After adjustment, the integrated mask module 400 can be firmly fixed in the required position by locking mechanisms (such as knobs, clamps, buckles, spring mechanisms, etc.) to prevent the mask from shifting due to slight animal movement or equipment vibration during anesthesia. This ensures that the integrated mask module 400 and the animal's head maintain a stable and close relative position throughout the experiment. The adjustable and fixed design ensures a good airtight fit between the mask module 400's cover 401 and the animal's head (especially the mouth and nose), effectively preventing anesthetic gas leakage from the mask's edges. This guarantees efficient use of the anesthetic and stable depth of anesthesia, while also preventing anesthetic gas leakage and contamination of the experimental environment. Simultaneously, precise positioning avoids undue pressure on the animal's head and face, improving animal comfort. For experiments requiring standardized procedures, the repeatable positioning also helps maintain consistent anesthesia conditions across different experiments or animals, improving the comparability and reproducibility of experimental data.The panel 301, serving as the main support, has a flat bearing surface for placing experimental targets. Its dimensions can be selected as 300mm × 250mm × 50mm to accommodate the size of most small experimental animals and provide stable support. Optionally, the ear clip 306 is arranged in a vertically slidable manner (e.g., a telescopic rod, threaded sleeve, etc.), and / or the axial length of the ear clip 306 is telescopically adjustable; and the ear clip 306 can be locked after adjustment; for example, by using mechanisms such as telescopic rods, threaded sleeves, motors, cylinders, or hydraulic cylinders for adjustment or locking; or by using a slide rail and a pin to achieve sliding and locking.

[0059] In this embodiment, the exhaust gas collection module has its first input end connected to the exhaust gas outlet of the induction chamber module 200 via a pipeline with a one-way valve, and its second input end connected to the exhaust gas outlet of the integrated mask module 400 via a pipeline with a one-way valve. The mixing chamber outlet of the exhaust gas collection module is connected to the exhaust gas treatment device 700. This module is used to collect and guide exhaust gas from the induction chamber module 200 and / or the integrated mask module 400, and to prevent backflow of exhaust gas between different pathways. Optionally, the one-way valve is a low-opening-pressure spring-loaded one-way valve with an opening pressure less than 1 cmH2O. Optionally, the volume of the mixing chamber is less than 5 mL to reduce dead space and gas retention. By setting up a common exhaust gas collection module and connecting its first and second input ends to the exhaust gas outlets of the induction chamber module 200 and the integrated mask module 400 respectively via pipelines, while connecting its mixing chamber outlet to a unified exhaust gas treatment device 700, a centralized exhaust gas collection and transportation path is constructed. This allows exhaust gases generated from different working units within the system (induction chamber module 200 and integrated mask module 400) to be collected into a single main pipeline and then purified by the same exhaust gas treatment device 700. This avoids configuring separate exhaust gas treatment pipelines and devices for each exhaust gas source, thereby significantly simplifying the external pipeline layout of the system, reducing the number and cost of hardware, improving the system integration, and unifying the maintenance points for exhaust gas treatment (such as replacing activated carbon filter canisters), thus improving maintenance convenience. One-way valves are installed on each pipeline connecting the induction chamber module 200 and the integrated mask module 400 to the exhaust gas collection module. This is a measure to prevent mutual interference between multiple exhaust gas systems. The directional conduction characteristic of the one-way valves ensures that exhaust gas can only flow from each anesthesia unit to the exhaust gas collection module, strictly preventing reverse flow. When a unit (such as the induction chamber module 200) is emitting high-concentration exhaust gas, the one-way valves can effectively prevent this exhaust gas from flowing back into another unit (such as the integrated mask module 400) that may not be working or is in a low-pressure state at the time, avoiding the diffusion of anesthetic exhaust gas in unwanted paths, thereby ensuring the independence and purity of the gas environment inside each anesthesia unit. When the system's operating state changes, airflow fluctuates, or the downstream suction force changes, the one-way valves can prevent gas from flowing back from the collection module or main pipe into each branch, maintaining the stability of the internal pressure of each anesthesia unit and preventing external gas interference.The one-way valve adopts a low-opening-pressure spring-loaded one-way valve, and the opening pressure is set to less than 1 cmH2O, which reduces the flow resistance of exhaust gas. The pressure generated by the exhalation of animals (especially small animals) is very weak. The low opening pressure ensures that even a very weak exhalation airflow can easily push open the valve disc, allowing the exhaust gas to be discharged smoothly. This avoids increased exhalation resistance, exhaust gas retention, or even respiratory distress in animals caused by excessively high valve opening pressure. The volume of the mixing chamber is designed to be less than 5 mL, minimizing the residence space (dead space) of exhaust gas in the collection module. This ensures that exhaust gas is almost not retained in the collection module and can be discharged quickly. It reduces the mixing of exhaust gas generated at different times in the chamber, helps to respond quickly to the animal's respiratory rhythm, and reduces the risk of residual and diffused anesthetic exhaust gas inside the system.

[0060] In this embodiment, the main control unit 500 is electrically connected to the precision injection pump 103 in the electro-injection nebulization drug delivery module 100, the concentration sensor 207 in the induction chamber module 200, the MEMS hot-film flow sensor chip 404 in the integrated mask module 400, and the gas path switching module 600. The main control unit 500 is configured to: during the induction phase, control the flow rate of the precision injection pump 103 in a closed loop according to the concentration signal fed back by the concentration sensor 207 to adjust the anesthetic concentration in the induction chamber module 200; during the maintenance phase, control the flow rate of the precision injection pump 103 in a closed loop according to the animal respiratory rate and / or tidal volume signal fed back by the integrated mask module 400 to adjust the anesthetic concentration in the mask. Optionally, the main control unit includes an isolated sampling circuit and a digital signal processor. The isolated sampling circuit is connected to a composite cable to collect sensor signals, and the digital signal processor runs a PID control algorithm. It is connected to the injection pump of the electro-nebulization module and a high-voltage power supply via control output interfaces. The main control unit adjusts the output voltage of the high-voltage power supply through an isolated digital-to-analog converter and drives the stepper motor of the injection pump through a pulse-width modulation signal, thus forming a closed-loop control circuit. The main control unit 500, as the control core of the system, is configured to execute different sensor-feedback-based closed-loop control strategies during the induction and maintenance anesthesia phases. During the induction phase, the main control unit 500 compares the actual anesthetic concentration signal fed back by the concentration sensor 207 in the induction chamber module 200 with a preset target concentration. It then adjusts the flow rate of the precision injection pump 103 in real time using a closed-loop control algorithm (such as PID), thereby precisely controlling the nebulization output. This ensures that the concentration inside the induction chamber module 200 quickly and smoothly reaches and stabilizes at the set value, achieving rapid and safe induction without overshoot. During the maintenance phase, based on the real-time respiratory rate and / or tidal volume signals of the animal fed back by the MEMS hot-film flow sensor chip 404 in the integrated mask module 400, the flow rate of the precision injection pump 103 is dynamically adjusted through a closed-loop control algorithm (such as PID), thereby precisely adjusting the anesthetic output according to the animal's immediate physiological state. This phased, closed-loop control strategy based on different key parameters realizes an intelligent transition from "environmental concentration control" to "individual physiological feedback control" in the anesthesia process, significantly improving the accuracy, safety, and automation level of the entire anesthesia process (from induction to maintenance). The isolation sampling circuit inside the main control unit 500 is used to collect various sensor signals (such as concentration signals and respiratory flow signals) from the composite cable. The electrical isolation design effectively prevents common-mode interference, ground loop interference, or potential high-voltage intrusion that may be introduced from the sensor side, protecting the core circuit of the main control unit 500 and ensuring the accuracy and safety of weak bioelectrical signal acquisition. The digital signal processor is responsible for efficiently running complex control algorithms (such as PID algorithms) for real-time data processing and decision-making. The control output interface outputs high-precision control commands based on the processing results.Precise control of electrostatic nebulization intensity is achieved by adjusting the output voltage of the high-voltage power supply through an isolated digital-to-analog converter; precise adjustment of the anesthetic fluid flow rate is achieved by driving the stepper motor of the infusion pump through a pulse width modulation signal. This complete hardware link, from signal acquisition and processing to multi-channel output, forms the foundation of a highly reliable and precise closed-loop control circuit. The main control unit 500 is not only connected to the nebulization module and sensors, but also electrically connected to the gas path switching module 600. This allows the main control unit 500 to control the actions of the gas path switching module 600 according to a preset workflow (such as switching from induction to maintenance) or received instructions, thereby coordinating the delivery path of the anesthetic gas flow. At the same time, the main control unit 500 can integrate and process status information from different modules (such as whether the concentration is up to standard, whether breathing is abnormal, and whether the gas path position is correct) and execute comprehensive logical judgments. For example, during the maintenance phase, when the respiratory rate is lower than the safety threshold, it automatically reduces the anesthetic output and triggers an alarm. This centralized coordination and control enables the orderly and collaborative operation of multiple subsystems such as nebulization, delivery, monitoring, and waste gas management, improving the integration, intelligence, and operational reliability of the entire anesthesia system. The main control unit 500, as the intelligent hub of the system, executes a phased closed-loop control algorithm, using environmental concentration signals and individual physiological respiratory signals as control bases respectively, to achieve real-time, adaptive, and precise adjustment of anesthetic output; and through internal isolation sampling, digital signal processing, and multi-channel control output structure, it constructs a safe, accurate, and reliable closed-loop control hardware loop; at the same time, it coordinates and manages key actions such as gas path switching, ensuring the collaborative work of multiple modules.

[0061] The beneficial effects of the small animal anesthesia experimental device of the present invention: 1. Significantly Improved Anesthesia Efficiency: This invention employs a gas-assisted coaxial electro-spray nozzle 101, delivering anesthetic through an inner central liquid needle 1011 while applying high-voltage electrostatic discharge. High-speed compressed air is introduced through an outer annular gas path, creating a dual atomization mechanism in the gas-liquid mixing zone. Under conditions of 0.1 MPa pressure and 1 mL / h flow rate, droplet size can reach 1 μm-5 μm, smaller than traditional ultrasonic nebulization (typically >5 μm) or vapor canister anesthesia (which relies on gas evaporation and has a slow concentration response). Submicron-sized droplets can efficiently deposit in the alveoli, significantly improving anesthetic bioavailability, shortening induction time by 30%-50%, and reducing anesthetic consumption by more than 35%, achieving rapid induction and precise maintenance.

[0062] 2. Maintaining closed-loop precision control and maneuverability during anesthesia to ensure safety: The integrated anesthesia mask incorporates a MEMS hot-film flow sensor chip 404 to monitor respiratory rate and tidal volume in real time. The shunt ratio between the sampling branch 403 and the main flow channel 402 is precisely controlled at 15%, ensuring high sensitivity detection of weak respiratory signals. The main control unit 500 runs a PID control algorithm, dynamically adjusting the flow rate of the precision infusion pump 103 (0.1 mL / h-10 mL / h) based on the deviation between the measured respiratory rate and the preset target, forming a closed-loop feedback system with millisecond-level response. When the respiratory rate falls below the safety threshold or the tidal volume is abnormal, the system automatically reduces the anesthetic output and triggers an alarm, effectively preventing respiratory depression or death caused by excessive anesthesia; when the anesthesia is too shallow, the system automatically increases the output, ensuring stable vital signs of the animal during surgery and significantly improving the reliability of experimental data.

[0063] 3. The system integrates a rapid induction chamber and a maintenance anesthesia mask, achieving rapid switching between induction and maintenance anesthesia via a gas path switching module 600. During the induction phase, the animal quickly reaches anesthesia within the chamber, with the concentration sensor 207 monitoring in real time and implementing closed-loop control to ensure a smooth induction process without overshoot. After induction, the system switches to mask maintenance anesthesia, with the mask recognition function automatically matching the animal species and anesthesia parameters, reducing operation time by more than 80%. The animal anesthesia platform 300 is equipped with a slide rail 304, a sliding bracket 305, and an ear clip 306, allowing for flexible adjustment of the integrated mask module 400 to ensure a perfect fit to the animal's head and accommodate the needs of animals of different sizes.

[0064] 4. By incorporating a waste gas collection module with a one-way valve, the rapid induction chamber and anesthesia masks can share the same waste gas treatment device 700, simplifying the system structure, reducing costs, and ensuring that multiple waste gas streams do not interfere with each other and have no backflow risk. The low-opening-pressure one-way valve ensures smooth discharge of animal exhaled gases, and the small dead space design of the mixing chamber reduces anesthetic retention. This design makes the waste gas treatment system more compact and efficient, suitable for animal anesthesia experiments of various scales.

[0065] 5. Modular integrated design, convenient and reliable operation: Each module adopts quick-connect interfaces and standardized connections, making installation and maintenance simple. The high-voltage power supply of the electro-spray atomization module is isolated and shielded to ensure electrical safety. The top cover 204 of the rapid induction chamber is equipped with a silicone sealing strip and a latch 203. The air distribution holes 206 of the annular air distribution pipe 205 inside the chamber are inclined at 30°-60°, ensuring uniform airflow dispersion without dead zones. The manual knob of the air path switching module 600 has a positioning feel, and the micro switch outputs a position signal to achieve electrical linkage with the main control unit.

[0066] In summary, this invention integrates gas-assisted electro-nebulization technology, MEMS respiratory monitoring, PID closed-loop control, and dual-mode switching to construct an efficient, safe, intelligent, and convenient small animal anesthesia system. This significantly improves the standardization level of animal experiments, data reliability, and operator safety, and has extremely high clinical application value and promising prospects for scientific research promotion.

[0067] Matters not covered in this invention are common knowledge.

[0068] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A small animal anesthesia experimental apparatus, characterized in that, include: The electro-injection nebulization drug delivery module (100) is used to form a high-voltage electrostatic field and use high-speed compressed air to perform secondary nebulization on the anesthetic droplets that have been initially nebulized by the high-voltage electrostatic field, so as to generate anesthetic aerosols with a particle size of 1μm-5μm and output them. The induction chamber module (200) is switchably connected to the output of the electro-injection nebulization drug delivery module (100) to contain the experimental target and enable the experimental target to quickly enter an anesthetic state in the anesthetic aerosol environment; The animal anesthesia platform (300), located downstream of the induction chamber module (200), is used to carry and fix the experimental target for subsequent experiments; An integrated mask module (400) is adjustablely mounted on an animal anesthesia platform (300) and switchably connected to the output of an electro-injection nebulizer module (100) for real-time monitoring of the respiratory rate and / or tidal volume of the experimental target wearing the mask. The main control unit (500) is electrically connected to the electro-injection nebulizer delivery module (100), the induction chamber module (200) and the integrated mask module (400), respectively, and is used to adjust the concentration of anesthetic in the induction chamber module (200) during the induction phase, or to dynamically adjust the output of anesthetic delivered to the integrated mask module (400) during the maintenance anesthesia phase.

2. The small animal anesthesia experimental apparatus according to claim 1, characterized in that, The output end of the electro-injected nebulizer delivery module (100) is set as a gas path switching module (600). The first output end of the gas path switching module (600) is connected to the induction chamber module (200), and the second output end of the gas path switching module (600) is connected to the integrated mask module (400). The gas path switching module (600) is used to selectively deliver the anesthetic aerosol generated by the electro-injected nebulizer delivery module (100) to either the induction chamber module (200) or the integrated mask module (400).

3. The small animal anesthesia experimental apparatus according to claim 1, characterized in that, The electro-injection atomized drug delivery module (100) includes an air-assisted coaxial electro-spray nozzle (101), a high-voltage electrostatic generator (102), a precision injection pump (103), and a compressed air source (104). The air-assisted coaxial electric spray nozzle (101) adopts a coaxial structure with internal liquid and external gas. The inner layer of the air-assisted coaxial electric spray nozzle (101) is connected to a precision injection pump (103), and the outer layer of the air-assisted coaxial electric spray nozzle (101) is connected to a compressed air source (104). The high-voltage electrostatic generator (102) is connected to the inner layer of the air-assisted coaxial electrospray nozzle (101). The anesthetic liquid is transported through the inner layer and a high-voltage electrostatic field is formed at the outlet to perform preliminary atomization of the anesthetic liquid. At the same time, the high-speed compressed air introduced into the outer layer is used to perform secondary atomization of the anesthetic droplets that have been pre-atomized by the high-voltage electrostatic field to generate anesthetic aerosols with a particle size of 1μm-5μm and output them.

4. The small animal anesthesia experimental apparatus according to claim 3, characterized in that, The air-assisted coaxial electro-spray nozzle (101) includes an annular air path system and a central liquid path system; The annular gas path system is coaxially sleeved on the outside of the central liquid path system. The inner central liquid path system is connected to the precision injection pump (103), and the outer annular gas path system is connected to the compressed air source (104). The high-voltage electrostatic generator (102) is connected to the central liquid circuit system, which delivers anesthetic liquid through the central liquid circuit system and forms a high-voltage electrostatic field at the outlet to initially atomize the anesthetic liquid; The end air chamber (107) of the annular airway system is used to form a gas-liquid mixing zone. The high-speed compressed air delivered by the annular airway system atomizes the anesthetic droplets that have been initially atomized by the central liquidway system, and generates anesthetic aerosols. The anesthetic aerosols are then pushed into the air delivery pipeline and output.

5. The small animal anesthesia experimental apparatus according to claim 4, characterized in that, The central fluid circuit system includes a central fluid needle (1011), which is made of medical-grade 316L stainless steel capillary with an inner diameter of 0.15mm-0.8mm and an outer diameter of 0.6mm-1.0mm. The tip cone angle of the central fluid needle (1011) is 30°-60°. The central liquid needle (1011) is encased in an insulating sleeve (1013), which is a PEEK micro tubing with a wall thickness of 0.2mm-0.5mm. The inlet end of the central liquid needle (1011) is connected to the precision injection pump (103) through a high-pressure isolation liquid circuit pipe, and the outlet end of the central liquid needle (1011) is 1.0cm-3.0cm away from the outlet of the annular gas circuit.

6. The small animal anesthesia experimental apparatus according to claim 5, characterized in that, The annular air passage system includes an annular air chamber (1014), which is a PEEK micro-tube with an annular gap width of 0.1mm-0.3mm and an annular diameter of 1.5mm-3.0mm; The air inlet of the annular air chamber (1014) is connected to the compressed air source (104), and a copper ring (106) is provided on the outer wall of the air outlet of the annular air chamber (1014). The copper ring (106) is coaxially arranged with the annular air chamber (1014), and the diameter of the copper ring (106) is 2mm-5mm. An airflow rectification structure is set inside the annular air cavity (1014). The airflow rectification structure adopts an annular perforated plate (1015). Multiple axial through holes are evenly distributed along the circumference of the annular perforated plate (1015). The diameter of the axial through holes is 0.2mm-0.5mm and the plate thickness is 0.3mm-1.0mm.

7. The small animal anesthesia experimental apparatus according to any one of claims 1 to 6, characterized in that, The induction chamber module (200) includes a housing (201); The top of the housing (201) is provided with a top cover (204) that is sealed to the top opening by a hinge (202), a latch (203) and a sealing strip. The top cover (204) is provided with an air outlet, which is connected to the exhaust gas treatment device (700). The bottom of the box (201) is provided with an annular air distribution pipe (205) and an air inlet. The air inlet is connected to the annular air distribution pipe (205). The annular air distribution pipe (205) is densely covered with air distribution holes (206) so that the gas enters through the air inlet and rises evenly through the air distribution holes (206) of the annular air distribution pipe (205). The diameter of the air distribution holes (206) is 0.3mm-0.8mm, the hole spacing is 5mm-15mm, and the opening direction of the air distribution holes (206) forms an angle of 30°-60° with the horizontal plane so that the airflow is uniformly dispersed in the cabin. The induction chamber module (200) also includes a concentration sensor (207). The concentration sensor (207) is installed at the center of the inner wall of the box (201) via a quick-connect sealing connector and is electrically connected to the main control unit (500). The main control unit (500) adjusts the precision injection pump (103) of the electro-injection nebulizer module (100) through a PID control algorithm based on the feedback signal from the concentration sensor (207). The main control unit (500) has preset PID parameters for different box (201) volumes to facilitate automatic matching.

8. The small animal anesthesia experimental apparatus according to any one of claims 1 to 6, characterized in that, The integrated face mask module (400) includes a cover (401), which is provided with an independent air inlet and an air outlet. Both the air inlet and the air outlet are equipped with a one-way valve so that gas enters through the air inlet and is discharged through the air outlet. The air outlet of the cover (401) is configured as a split-flow airway structure, which includes a main flow channel (402) and a sampling branch (403). The airflow cross-sectional area of ​​the branch is 15% of the cross-sectional area of ​​the main flow channel (402). The inlet end of the main channel (402) and the inlet end of the sampling branch (403) meet at the inlet end of the outlet. The outlet end of the main channel (402) and the outlet end of the sampling branch (403) meet at the outlet end of the outlet. The outlet is connected to the exhaust gas treatment device (700) through an exhaust gas hose. The top of the inner wall of the cover (401) is provided with a nose support structure (405) to cooperate with the bridge of the nose of the experimental target to limit the depth of mouth and nose insertion and make the tip of the nose face the split point of the main channel (402) and the sampling branch (403).

9. The small animal anesthesia experimental apparatus according to claim 8, characterized in that, The enclosure (401) also includes: The MEMS hot-film flow sensor chip (404) is located in the sampling branch (403) and is used to detect the flow rate and direction of respiratory airflow. A sensor mount is used to fix the MEMS hot-film flow sensor chip (404) on the sampling branch (403) and form a sampling cavity; The signal conditioning circuit board is electrically connected to the MEMS hot-film flow sensor chip (404) and is used to amplify and filter the sensor signal; The composite transmission cable is a multi-core shielded signal cable. The first end is connected to the miniature aviation plug of the housing (401), and the second end is connected to the main control unit (500).

10. The small animal anesthesia experimental apparatus according to any one of claims 1 to 6, characterized in that, The main control unit (500) is electrically connected to the precision injection pump (103) in the electronic injection atomization drug delivery module (100), the concentration sensor (207) in the induction chamber module (200), the MEMS hot film flow sensor chip (404) in the integrated mask module (400), and the gas path switching module (600), respectively. The main control unit (500) is configured as follows: During the induction phase, the flow rate of the precision injection pump (103) is controlled in a closed loop based on the concentration signal fed back by the concentration sensor (207) to adjust the concentration of anesthetic in the induction chamber module (200). During the maintenance phase, the flow rate of the precision injection pump (103) is controlled in a closed loop based on the animal's respiratory rate and / or tidal volume signals fed back by the integrated mask module (400) to adjust the concentration of anesthetic in the mask.

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