A new tracheal catheter atomization device and its control method

Abstract

The application provides a novel trans-tracheal catheter atomization device and a control method thereof. The novel trans-tracheal catheter atomization device comprises a drug delivery catheter, an automatic injection unit and a four-way connector. One end of the drug delivery catheter is connected to the automatic injection unit, the middle part is arranged in the four-way connector and can be axially positioned through a knobbed interface; the four-way connector is provided with a side connection port for connecting a breathing machine breathing circuit, a side port for inserting a fiber bronchoscope and another end connection port for connecting a tracheal catheter. The drug delivery catheter passes through the inside of the tracheal catheter, and the distal end of the drug delivery catheter is provided with an atomization nozzle, which comprises a drug replacement one-way valve, a drug adding one-way valve, a plurality of side spray holes and a plurality of end spray holes. The device can realize local atomization drug delivery through the tracheal catheter.

Description

Technical Field

[0001] This application relates to the field of medical nebulizers, and more specifically, to a novel transtracheal nebulization device and its control method. Background Technology

[0002] Postoperative pulmonary complications are a major cause of prolonged hospital stays and increased perioperative mortality in surgical patients, seriously threatening their lives. Nebulized inhalation is a method of drug delivery that uses a nebulizer to atomize liquid medication into aerosol particles, which are then inhaled into the airways and lungs. Due to its high concentration in the airways and few systemic adverse reactions, it has become a primary means of treating respiratory diseases. Therefore, nebulized therapy during the perioperative period for patients with postoperative pulmonary complications is considered an effective way to reduce its incidence.

[0003] Currently, surgical patients and critically ill patients often require invasive ventilation during the perioperative and intensive care periods. When administering intratracheal medication to patients with indwelling endotracheal tubes, the usual method is to cut a thin plastic pump tube, insert it into the endotracheal tube, and then use a syringe to push the medication from the outer end of the pump tube, allowing it to drip into the intubation tube and enter the human airway. However, this method has low drug delivery efficiency and is also prone to problems such as drug deposition and uneven distribution. Clinically used medical devices for intratracheal drug delivery mainly include endoscopic microcatheters. Endoscopic microcatheters assist endoscopy in single-dose intratracheal nebulization, with their nozzles spraying liquid medication as tiny droplets onto the desired site. However, they lack the ability to administer medication while maintaining ventilation, increasing the risk of hypoxia for patients already in critical conditions such as airway obstruction. Furthermore, they cannot be stably placed in the endotracheal tube for extended periods; they require repeated insertion and removal, which is inconvenient and prone to secondary contamination.

[0004] Therefore, there is an urgent need for a new type of nebulizer that can solve the above-mentioned problems of uneven drug deposition and distribution, and can administer drugs while providing ventilation and can be stably placed in the endotracheal tube for a long time.

[0005] Therefore, this application provides a novel nebulizer via endotracheal tube and its control method to solve one of the aforementioned technical problems. Summary of the Invention

[0006] The purpose of this application is to provide a novel transtracheal nebulizer and its control method, which can solve at least one of the aforementioned technical problems. The specific solution is as follows: According to a specific embodiment of this application, in a first aspect, this application provides a novel endotracheal nebulizer, comprising a drug delivery catheter (2), an automatic injection unit (1), and a control circuit (18). One end of the drug delivery catheter (2) is connected to the automatic injection unit (1), and the middle part of the drug delivery catheter (2) is inserted into a four-way connector and can be selectively fixed to any axial position of the drug delivery catheter (2) via an interface (3) with a knob. The four-way connector includes a side connection port (4) for connecting a ventilator (17). The breathing circuit of the bronchoscope includes a side port (5) for inserting a fiberoptic bronchoscope to position the administration catheter (2) in the patient's airway and a connection port (6) for connecting the endotracheal tube (7). The administration catheter (2) passes through the endotracheal tube (7) and has a nebulizer nozzle (12) at its distal end. The nebulizer nozzle (12) includes a dressing change check valve (13), a drug delivery check valve (14), multiple side nozzles (15), and multiple end nozzles (16). The control circuit (18) is connected to the self- The automatic injection unit (1) is connected to the control circuit (18) for receiving ventilator monitoring parameters output by the ventilator (17). The ventilator monitoring parameters include at least airway pressure parameters, exhaled volume parameters, and end-expiratory carbon dioxide waveform parameters. The control circuit (18) is used to identify the inspiratory and expiratory phases in the current respiratory cycle based on the ventilator monitoring parameters and determine the inspiratory start time. After identifying the inspiratory start time, the control circuit (18) assigns the drug administration task to be performed to the current respiratory cycle to obtain the target drug administration dose corresponding to the current respiratory cycle. The control circuit (18) generates a step-driven control sequence for the automatic injection unit (1) based on the target drug administration dose corresponding to the current respiratory cycle to perform drug delivery during the inspiratory phase and stop or limit drug delivery during the expiratory phase. When the control circuit (18) identifies the inspiratory and expiratory phases, it makes a joint judgment based on the trend of airway pressure change, the relationship of exhaled volume change, and the relationship of end-expiratory carbon dioxide waveform change, and introduces a hysteresis retention mechanism when switching phases.

[0007] According to a specific embodiment of this application, in a second aspect, this application provides a control method for a novel transtracheal nebulizer, applied to the novel transtracheal nebulizer described in any one of the first aspects. The method includes: acquiring ventilator monitoring parameters output by a ventilator (17), and preprocessing the ventilator monitoring parameters by a control circuit (18) to obtain a monitoring parameter sequence for determining the respiratory cycle; the control circuit (18) identifies the inspiratory phase and expiratory phase in the current respiratory cycle according to the monitoring parameter sequence, and determines the inspiratory start time; wherein, the control circuit (18) identifies the inspiratory phase and expiratory phase... During the gas phase, a joint determination is made based on the trend of airway pressure change, the relationship between exhaled air volume change and the relationship between end-expiratory carbon dioxide waveform change, and a hysteresis retention mechanism is introduced during phase switching to suppress false switching caused by short-term fluctuations; after identifying the inspiratory start time, the control circuit (18) assigns the drug administration task to be executed to the current respiratory cycle to obtain the target drug administration dose corresponding to the current respiratory cycle; the control circuit (18) generates a step-driven control sequence for the automatic injection unit (1) based on the target drug administration dose corresponding to the current respiratory cycle to perform drug delivery during the inspiratory phase and stop or limit drug delivery during the expiratory phase.

[0008] Compared with the prior art, the above-described solutions of this application have at least the following beneficial effects: This application provides a novel transtracheal nebulizer. By combining a drug delivery catheter, a four-way connector, a nebulizer nozzle, an automatic injection unit, and a control circuit, the device can directly deliver medication to the target location in the patient's airway via the endotracheal catheter without interrupting the ventilator's ventilation circuit. The position of the drug delivery catheter can be observed and located using a fiberoptic bronchoscope, thereby reducing ineffective drug deposition in the respiratory circuit and upstream of the artificial airway. Simultaneously, the control circuit identifies the inspiratory and expiratory phases based on monitoring parameters such as airway pressure, expiratory volume, and end-expiratory carbon dioxide waveform from the ventilator. It then generates a step-driven control sequence for the automatic injection unit based on the current respiratory cycle, ensuring that the medication is primarily propelled during the inspiratory phase and stopped or restricted during the expiratory phase. This improves the synchronization between medication release and the patient's respiratory airflow, enhancing the efficiency of nebulized medication delivery to the distal airway. Furthermore, through multi-parameter joint judgment and hysteresis maintenance mechanisms, the risk of phase misjudgment caused by short-term fluctuations can be reduced, making the drug delivery process more stable, safe, and accurate. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the overall structure of a novel nebulizer via endotracheal tube according to this application; Figure 2 This is a schematic diagram of the atomizing nozzle in this application; Figure 3An exemplary control method for a novel endotracheal nebulizer is shown; The attached figures are labeled as follows: 1-Automatic injection unit; 2-Drug delivery tubing; 3-Interface with knob; 4-Side connection port; 5-Side opening; 6-Other end connection port; 7-Tracheal tubing; 8-Outer connector; 9-Instrument inflation port; 10-Fixing cuff; 11-Visual camera; 12-Nebulizer nozzle; 13-Drug change check valve; 14-Drug administration check valve; 15-Side nozzle; 16-End nozzle; 17-Ventilator; 18-Control circuit. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0011] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “said,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0012] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0013] It should be understood that although the terms first, second, third, etc., may be used in the embodiments of this application, these descriptions should not be limited to these terms. These terms are only used to distinguish the descriptions. For example, first may also be referred to as second without departing from the scope of the embodiments of this application, and similarly, second may also be referred to as first.

[0014] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0015] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0016] It should be noted that any symbols and / or numbers present in the specification that are not marked in the accompanying drawings are not reference numerals.

[0017] The optional embodiments of this application are described in detail below with reference to the accompanying drawings.

[0018] The embodiments provided in this application are embodiments of a novel nebulizer via a tracheal tube.

[0019] The following is combined Figure 1 The embodiments of this application will be described in detail.

[0020] Figure 1 This is a schematic diagram of the overall structure of a novel nebulizer via endotracheal tube according to this application; In some embodiments, combined with Figure 1 As shown, a novel endotracheal nebulizer includes a drug delivery catheter (2) and an automatic injection unit (1). One end of the drug delivery catheter (2) is connected to the automatic injection unit (1). The middle part of the drug delivery catheter (2) is inserted into a four-way connector and can be selectively fixed to any position along the axis of the drug delivery catheter (2) through an interface (3) with a knob. The four-way connector includes: a side connection port (4) for connecting to the breathing circuit of a ventilator (17); a side opening (5) for inserting a fiberoptic bronchoscope to position the drug delivery catheter (2) in the patient's airway; and a connection port (6) at the other end for connecting to an endotracheal tube (7). The drug delivery catheter (2) passes through the endotracheal tube (7) and has a nebulizing nozzle (12) at its distal end. The nebulizing nozzle (12) includes a dressing change one-way valve (13), a drug addition one-way valve (14), multiple side nozzles (15) and multiple end nozzles (16).

[0021] As a feasible implementation, Figure 1 The device shown generally includes an automatic injection unit (1), a drug delivery catheter (2), a four-way connector, an endotracheal tube (7), a nebulizer nozzle (12), a ventilator (17), and a control circuit (18).

[0022] The automatic injection unit (1) is located at the proximal end of the device and is used to apply propulsion force to the drug solution; the drug delivery catheter (2) serves as a drug delivery channel, with its proximal end connected to the automatic injection unit (1) and its distal end extending into the tracheal tube (7); the four-way connector serves as the intersection of the ventilation path, the microscopic observation path and the drug delivery path, enabling the device to complete local drug delivery while maintaining the existing ventilation conditions.

[0023] In one specific embodiment, the drug delivery catheter (2) passes through a four-way connector and is locked in position via a knob-equipped interface (3). The knob-equipped interface (3) does not change the delivery direction of the drug delivery catheter (2), but rather mechanically fixes its current position after the operator has completed the axial advancement or retraction of the drug delivery catheter (2) to prevent positional drift during drug delivery. The specific placement of the drug delivery catheter (2) in the patient's airway can be observed and confirmed by inserting a fiberoptic bronchoscope through the side opening (5). When the operator observes that the nebulizer nozzle (12) has reached the vicinity of the target airway area, the operator tightens the knob-equipped interface (3) to keep the drug delivery catheter (2) in that position.

[0024] In some embodiments, Figure 1 The side connection port (4) is used to connect the breathing circuit of the ventilator (17), and the other end connection port (6) is used to connect the endotracheal tube (7). Thus, after the device of this application is connected, the ventilation path between the ventilator (17) and the patient's artificial airway remains connected. The side port (5) is used to insert a fiberoptic bronchoscope, so that the operator can complete the positioning operation without disconnecting the breathing circuit.

[0025] also, Figure 1 The diagram also shows an outer connector (8), a syringe inflation port (9), a fixed air bag (10), and an auxiliary intubation visualization camera (11). This part of the structure is mainly used to reflect the compatibility between the device of this application and existing mature endotracheal tube components. The outer connector (8) is used for external connection, the syringe inflation port (9) is connected to the fixed air bag (10) and is used to inflate or deflate the fixed air bag (10), and the auxiliary intubation visualization camera (11) is used to observe the intubation status.

[0026] In some embodiments, the drug delivery catheter (2) is disposed inside the four-way connector and extends along the inner lumen of the tracheal tube (7), and the atomizing nozzle (12) covers the tail of the drug delivery catheter (2).

[0027] As a specific embodiment, after the drug delivery catheter (2) enters the four-way connector, it extends distally along the inner lumen of the tracheal tube (7). The atomizing nozzle (12) is located at the tail of the drug delivery catheter (2) and moves synchronously with the drug delivery catheter (2). This arrangement allows the drug solution to bypass most of the space upstream of the breathing circuit and be directly delivered to the vicinity of the target airway.

[0028] For example, in one usage method, the operator first connects the other end of the connector (6) to the endotracheal tube (7), then connects the side connector (4) to the breathing circuit of the ventilator (17), and inserts the drug delivery catheter (2) into the four-way connector through the knob-equipped interface (3). The fiberoptic bronchoscope enters through the side opening (5) to observe the position of the nebulizer nozzle (12). When the nebulizer nozzle (12) reaches the target position, the drug delivery catheter (2) is fixed through the knob-equipped interface (3), thus completing the procedure. Figure 1 Preparation for use of the overall structure shown.

[0029] Figure 2 This is a schematic diagram of the atomizing nozzle in this application; In some embodiments, combined with Figure 2 As shown, the dosing check valve (14) is located inside the atomizing nozzle (12) on one side near the four-way connector, so that the liquid medicine is output in one direction from the proximal end to the distal end; multiple side nozzles (15) are arranged around the side wall of the atomizing nozzle (12); multiple end nozzles (16) are located at the end of the atomizing nozzle (12) away from the dosing check valve (14).

[0030] As a feasible implementation, Figure 2 The atomizing nozzle (12) shown is internally equipped with a dosing check valve (14) and a drug replacement check valve (13), and externally equipped with a side spray hole (15) and a lateral spray hole (16). The dosing check valve (14) is located inside the atomizing nozzle (12) near the proximal end. Its function is to allow the drug solution to flow from the proximal end of the drug delivery conduit (2) to the distal end of the atomizing nozzle (12), and to restrict the reverse flow of fluid in the distal direction. In this application, this feature is achieved by setting the valve body at the proximal end of the nozzle, and is used in the drug delivery state to ensure unidirectional controlled output of the drug solution.

[0031] In some embodiments, lateral nozzles (15) are arranged around the sidewall of the atomizing nozzle (12) to form a circumferential release path; lateral nozzles (16) are arranged on the distal end face of the atomizing nozzle (12) to form an axial forward release path.

[0032] In some embodiments, the dressing change check valve (13) is located inside the atomizing nozzle (12) on the side near the end-to-end nozzle (16); during the dressing change process, the automatic injection unit (1) performs a back suction action through the drug delivery conduit (2), causing the dressing change check valve (13) to open under negative pressure, so that the gas in the tracheal conduit (7) is injected back into the atomizing nozzle (12).

[0033] As a feasible embodiment, the one-way valve (13) is used for the medication change state corresponding to the medication dosing state. In the medication dosing state, the automatic injection unit (1) pushes the liquid medication along the administration conduit (2) to the distal end. After passing through the one-way valve (14), the liquid medication enters the front chamber of the nebulizer nozzle (12) and is then released through the lateral nozzle (15) and the end nozzle (16). In the medication change state, the automatic injection unit (1) no longer pushes forward but performs a back suction action, creating a negative pressure inside the administration conduit (2) and the nebulizer nozzle (12). The one-way valve (13) opens under the negative pressure, and the gas from the tracheal conduit (7) is injected back into the nebulizer nozzle (12) to assist in the return of the old liquid medication and the replacement of the medication chamber. Thus, Figure 2 The dual one-way valve structure shown serves the drug administration and drug change operations respectively.

[0034] As one specific embodiment, Figure 2 The corresponding flow path relationships are as follows: In the drug administration condition, the drug flow path is: starting from the automatic injection unit, through the drug administration conduit (2), the drug addition check valve (14), the front chamber of the atomizing nozzle (12), and up to the side spray hole (15) and the end spray hole (16) in sequence; In the drug replacement condition, the flow path is: starting from the automatic injection unit (1) to perform back suction, through the formation of negative pressure in the atomizing nozzle (12), the opening of the drug replacement check valve (13), the gas in the tracheal conduit (7) is reinjected into the atomizing nozzle (12), until the old drug is returned or the drug chamber is replaced.

[0035] In one specific application, when the atomizing nozzle (12) is near the target airway, the automatic injection unit (1) pushes the liquid medicine according to the instructions of the control circuit (18). The liquid medicine enters the nozzle through the dosing check valve (14) and is discharged from the side nozzle (15) and the end nozzle (16). When the liquid medicine needs to be replaced during the treatment stage, the control circuit (18) switches the control mode, the automatic injection unit (1) reverses the action, the replacement check valve (13) opens and forms a back suction replacement process.

[0036] In some embodiments, the ventilator (17) collects ventilator monitoring parameters in real time and sends them to the control circuit (18) through the data interface. The ventilator monitoring parameters include airway pressure, lung compliance, exhaled air volume, gas retention parameters, blood oxygen saturation, oxygenation index and end-expiratory carbon dioxide waveform parameters. The control circuit (18) outputs a medication change instruction or medication instruction to the automatic injection unit (1) based on the medication dosage information given by the expert diagnostic system.

[0037] As a feasible embodiment, the ventilator (17) serves as a data source, outputting in real time airway pressure, lung compliance, expiratory volume, gas retention parameters, blood oxygen saturation, oxygenation index, and end-expiratory carbon dioxide waveform parameters. These parameters are sent to the control circuit (18) via a data interface, and the control circuit (18) uses these parameters as the input basis for the control method. The expert diagnostic system provides medication dosage information to the control circuit (18), and the control circuit (18), after considering the current monitoring parameter status, outputs a medication change command or medication addition command to the automatic injection unit (1).

[0038] As a specific embodiment, airway pressure is used to describe the current ventilation pressure change, lung compliance is used to describe the lung mechanical state, expiratory volume and gas retention parameters are used to reflect ventilation efficiency and retention trend, blood oxygen saturation and oxygenation index are used to reflect the patient's oxygenation status, and end-expiratory carbon dioxide waveform parameters are used to reflect gas exchange changes related to the respiratory cycle. After reading the above parameters, the control circuit (18) does not directly drive the automatic injection unit (1) at fixed times, but uses them as the basis for subsequent respiratory cycle identification, drug delivery window determination, and safety judgment. This application can establish a control input channel by directly utilizing the existing monitoring capabilities of the ventilator (17) without adding independent external sensors.

[0039] For example, during a treatment process, the expert diagnostic system outputs the required dosage information for the current stage, and the ventilator (17) synchronously and continuously outputs monitoring parameters such as airway pressure and end-tidal carbon dioxide waveform. The control circuit (18) determines whether the current drug administration conditions are met based on this information. If they are met, a drug administration instruction is sent to the automatic injection unit (1). If a drug solution switching requirement is received or it is found that the current process should be switched to replacement, a drug replacement instruction is sent.

[0040] In some embodiments, the control circuit (18) executes a stepper motor injection control algorithm. After inputting the dosage and administration time on the display interface, it controls the stepper motor to drive the automatic injection unit (1) to complete the precise administration according to the acceleration phase, the constant speed phase and the deceleration phase. When the total number of pulses meets the pulse distribution of the acceleration phase and the deceleration phase, the control circuit (18) outputs a three-segment pulse control sequence according to the preset target speed. When the total number of pulses is insufficient to complete the acceleration phase and the deceleration phase at the preset target speed, the control circuit (18) recalculates the achievable maximum speed according to the total number of pulses and outputs a pulse control sequence based on the recalculated achievable maximum speed.

[0041] As a feasible embodiment, the automatic injection unit (1) adopts an injection propulsion structure driven by a stepper motor. The rotational motion of the stepper motor is converted into the axial displacement of the syringe piston through a mechanical transmission mechanism, thereby propelling the drug solution into the drug delivery catheter (2). After obtaining the dosage and administration time from the display interface, the control circuit (18) converts them into a pulse control task and controls the stepper motor to run according to the acceleration phase, the constant speed phase, and the deceleration phase. The acceleration phase is used to establish a stable motion state, the constant speed phase is used to complete the main propulsion amount, and the deceleration phase is used to smoothly end the propulsion, reducing mechanical impact and propulsion overshoot.

[0042] As a specific embodiment, when the total number of pulses is sufficient to satisfy the pulse allocation for the acceleration and deceleration phases, the control circuit (18) generates a complete three-segment pulse control sequence according to the preset target speed. When the total number of pulses is too small to fully experience the acceleration, constant speed, and deceleration processes while maintaining the preset target speed, the control circuit (18) does not forcibly adopt the original target speed, but instead recalculates the achievable maximum speed based on the total number of pulses and constructs a new pulse control sequence based on the recalculated achievable maximum speed. Specifically, the feasibility of the original target speed can be identified by judging whether the distance in the constant speed phase is negative. If it is not feasible, the maximum speed is recalculated and the control trajectory is reconstructed.

[0043] For example, in a drug delivery task, the control circuit (18) converts the target dosage into the corresponding total number of pulses, and calculates the number of pulses required for the acceleration and deceleration phases based on the set target speed, acceleration, and deceleration. If the remaining pulses are sufficient, there is a uniform propulsion process in between. If the remaining pulses are insufficient, the control circuit (18) redetermines the peak speed based on the current total pulse constraint and redistributes the acceleration and deceleration processes. Based on this method, the automatic injection unit (1) can maintain relatively stable propulsion accuracy under different dosages and different drug delivery times.

[0044] Based on the same concept, this application also provides a control method for a novel transtracheal nebulizer. This method is applied to the novel transtracheal nebulizer in any of the above embodiments to achieve control of the novel transtracheal nebulizer. If there are any unclear points in the following embodiments, please refer to any of the above embodiments.

[0045] Figure 3 An exemplary control method for a novel transtracheal nebulizer is shown, such as... Figure 3 As shown, it includes the following steps S1 to S4; S1. Obtain the ventilator monitoring parameters output by the ventilator (17), and preprocess the ventilator monitoring parameters by the control circuit (18) to obtain the monitoring parameter sequence used to determine the respiratory cycle; S2, control circuit (18) identifies the inspiratory and expiratory phases in the current respiratory cycle based on the monitoring parameter sequence and determines the inspiratory start time; S3. After identifying the inhalation start time, the control circuit (18) assigns the drug administration task to be performed to the current respiratory cycle and obtains the target drug administration dose corresponding to the current respiratory cycle. S4. The control circuit (18) generates a step-drive control sequence for the automatic injection unit (1) based on the target dosage corresponding to the current respiratory cycle, so as to perform drug delivery in the inspiratory phase and stop or limit drug delivery in the expiratory phase.

[0046] In some embodiments, the ventilator monitoring parameters output by the ventilator (17) are used as real-time inputs, processed by the control circuit (18), and the processing results are converted into execution instructions for the automatic injection unit (1).

[0047] The overall logic of this method is as follows: the ventilator (17) provides monitoring parameters related to the current ventilation, and the control circuit (18) extracts information that can be used to identify the respiratory cycle from these parameters. It identifies the current inspiratory and expiratory phases and determines the inspiratory start time. Based on this, the drug delivery task is assigned to the current respiratory cycle to obtain the target drug delivery amount corresponding to the current respiratory cycle. Then, the target drug delivery amount is converted into a step-driven control sequence of the automatic injection unit (1) to propel the drug solution during the inspiratory phase and stop or limit the propagation during the expiratory phase. Thus, a correspondence is established between the drug delivery action and the respiratory cycle.

[0048] As a feasible embodiment, this application does not introduce new hardware sensors, does not change the basic mechanical structure of the atomizing nozzle (12), and does not rely on additional valve groups. Instead, it builds a complete software control process based on the novel transtracheal duct atomizing device provided in the above embodiment.

[0049] In some embodiments, the ventilator monitoring parameters are preprocessed, including: time alignment of airway pressure parameters and end-expiratory carbon dioxide waveform parameters; filtering or removal of abnormal sampling points for monitoring parameters with fluctuations; extraction of candidate points for respiratory cycle boundaries based on the processed parameter sequence; wherein, when identifying the inspiratory and expiratory phases, the control circuit (18) makes a joint determination based on the trend of airway pressure change, the relationship between exhaled volume change and the relationship between end-expiratory carbon dioxide waveform change, and introduces a hysteresis hold mechanism during phase switching to suppress false switching caused by short-term fluctuations.

[0050] As a feasible embodiment, the purpose of the control circuit (18) in preprocessing the ventilator monitoring parameters is to improve the stability of respiratory cycle identification. Since there may be differences in the sampling time between the airway pressure parameters and the end-expiratory carbon dioxide waveform parameters, the control circuit (18) performs time alignment to ensure that the parameters at the same time point correspond to each other. For monitoring parameters with fluctuations or abnormal jumps, the control circuit (18) can perform filtering or abnormal sampling point removal to reduce the impact of noise on phase identification. Based on this, the control circuit (18) extracts respiratory cycle boundary candidate points from the processed parameter sequence to provide boundary basis for the determination of the inspiratory and expiratory phases.

[0051] As a specific embodiment, the control circuit (18) uses the trend of airway pressure change as one of the main criteria, and the relationship between the change in exhaled volume and the change in the end-expiratory carbon dioxide waveform as auxiliary criteria. When multiple criteria meet the inspiratory characteristics, the control circuit (18) determines that it has entered the inspiratory phase; when multiple criteria meet the expiratory characteristics, the control circuit (18) determines that it has entered the expiratory phase. A hysteresis holding mechanism is set during the phase switching process, that is, short-term reverse fluctuations of a single or a few sampling points are insufficient to trigger phase switching. Only when the parameter changes continuously meet the switching conditions will the control circuit (18) update the current phase state. Based on the embodiments of this application, misjudgments caused by short-term fluctuations can be significantly reduced.

[0052] For example, in a practical application, the airway pressure curve output by the ventilator (17) shows a brief fluctuation, while the exhaled volume and end-expiratory carbon dioxide waveform do not show phase change characteristics synchronously. Under the action of the hysteresis holding mechanism, the control circuit (18) maintains the original phase judgment unchanged, avoiding mistaking the brief disturbance as a new inspiratory start time or expiratory start time.

[0053] In some embodiments, the dosing task to be performed is assigned to the current respiratory cycle, including: determining the target dosing amount corresponding to the current respiratory cycle based on the total dosing amount, dosing time, and current respiratory cycle information; performing a compensation allocation for the first dosing cycle or the first dosing cycle after changing the medication based on the residual volume parameters of the dosing catheter (2) and the nebulizer nozzle (12); and when generating the step-driven control sequence, the control circuit (18) preferentially allocates the target dosing amount corresponding to the current respiratory cycle to be executed in the first part of the inspiratory phase, and then allocates the remaining dosing amount to be executed or not executed in the second part of the inspiratory phase, so that the dosing intensity in the first part of the inspiratory phase is higher than the dosing intensity in the second part of the inspiratory phase.

[0054] As a feasible embodiment, the total dosage and dosage time together define the overall treatment task, and the current respiratory cycle information defines the time window for drug administration within the current cycle. The control circuit (18) determines the target dosage corresponding to the current respiratory cycle based on these three parts of information, so that the total treatment task is discretely decomposed into each respiratory cycle. The residual volume parameter is used to characterize the volume that needs to be filled inside the drug delivery catheter (2) and the nebulizer nozzle (12) during the first advance or the re-advancement after drug change. Based on the residual volume parameter, the control circuit (18) performs compensation distribution in the first drug administration cycle or the first drug administration cycle after drug change to ensure that the amount of drug actually released from the nebulizer nozzle (12) meets the target requirements.

[0055] As a specific embodiment, when generating the step-driven control sequence, the control circuit (18) does not distribute the target dosage for the current cycle evenly throughout the entire inspiratory phase. Instead, it prioritizes the distribution during the first part of the inspiratory phase, and then distributes the remaining dosage during the second part of the inspiratory phase, or does not distribute it at all. In this application, this arrangement makes the dosage intensity in the first part of the inspiratory phase higher than that in the second part of the inspiratory phase, thereby causing the main dosage action to occur in a phase that is more conducive to the delivery of the drug solution to the distal airway. The first and second parts of the inspiratory phase are both determined based on the current respiratory cycle identification result, and the boundary between the first and second parts can be divided by the control circuit (18) according to the current cycle duration or the progress within the cycle.

[0056] For example, in one implementation, the control circuit (18) first calculates the theoretical single-cycle dosage based on the total dosage and dosage time, and then combines the residual volume parameter to obtain the actual dosage for this cycle. After the start of the inspiratory phase, the control circuit (18) allocates most of the propulsion tasks to the early part of the inspiratory phase and a smaller part to the later part of the inspiratory phase, or does not perform them in the later part if the later part is not conducive to propulsion. Based on this, the required correspondence between the dosage distribution within this cycle and the internal process of the respiratory cycle can be established.

[0057] In some embodiments, generating a step-driven control sequence for the automatic injection unit (1) includes: converting the target dosage corresponding to the current respiratory cycle into the target number of pulses based on the propulsion volume corresponding to the unit pulse; allocating the target number of pulses to multiple consecutive time periods based on the start time of the inspiratory phase, the time before the inspiratory phase, and the time after the inspiratory phase; outputting the pulse frequency in each time period according to the control methods of acceleration, uniform speed, and deceleration; when a medication change command is detected, the control circuit (18) controls the automatic injection unit (1) to perform a back-inhalation action, causing the medication change check valve (13) to open under negative pressure, and performing a pre-filling action based on the residual volume parameter after back-inhalation; when abnormal airway pressure, abnormal decrease in exhaled air volume, increased gas retention, or abnormal end-expiratory carbon dioxide waveform is detected, the control circuit (18) stops the pulse output of the current administration cycle and performs downgrade control or pause control for subsequent administration cycles.

[0058] As a feasible embodiment, the propulsion volume corresponding to a unit pulse is the basic parameter for the automatic injection unit (1) to perform the measurement. The control circuit (18) converts the target dosage corresponding to the current respiratory cycle into the target number of pulses based on the propulsion volume corresponding to a unit pulse. After the conversion is completed, the control circuit (18) allocates the target number of pulses to multiple consecutive time periods by combining the start time of the inspiratory phase, the first half time of the inspiratory phase, and the last half time of the inspiratory phase. The pulse output in each time period still follows the acceleration, uniform speed, and deceleration control mode, so that the propulsion action distributed in different time periods has a smooth mechanical execution process.

[0059] As a specific embodiment, when a medication change command is detected, the control circuit (18) stops the current forward propulsion task and controls the automatic injection unit (1) to perform a back suction action. The back suction action creates a negative pressure inside the drug delivery catheter (2) and the nebulizer nozzle (12). Under this negative pressure, the medication change check valve (13) opens. After the back suction is completed, the control circuit (18) controls the automatic injection unit (1) to perform a pre-filling action according to the residual volume parameters, so that the new drug solution is pushed to a position close to the release position of the nebulizer nozzle (12).

[0060] In some embodiments, the control circuit (18) also continuously detects abnormal operating conditions. When abnormal airway pressure, abnormal decrease in exhaled air volume, increased gas retention, or abnormal end-tidal carbon dioxide waveform are detected, the control circuit (18) stops the pulse output of the current dosing cycle and performs downgrade control or pause control for subsequent dosing cycles. Downgrade control may manifest as reducing the target dosage for subsequent cycles, shortening the dosing window, or reducing the pulse output intensity, while pause control may manifest as not continuing dosing until the abnormality is resolved.

[0061] For example, in one specific implementation, the control circuit (18) has already output a portion of the target pulse in the early part of the current inspiratory phase. When the ventilator (17) reports an abnormal increase in the current airway pressure and a decrease in the exhaled volume, the control circuit (18) stops outputting the remaining pulses, ceases the current cycle progression, and reserves the unfinished portion as a task to be processed in subsequent cycles. After the abnormality is resolved, the control circuit (18) then rearranges the subsequent progression according to the new respiratory cycle status.

[0062] Although the operations are described in a specific order in the accompanying drawings, this should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all of the operations shown to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0063] The apparatus and control method of this application can be implemented using standard programming techniques, and various method steps can be implemented using rule-based logic or other logic. It should also be noted that the terms "apparatus" and "module" as used herein and in the claims are intended to include implementations using one or more lines of software code and / or hardware implementations and / or devices for receiving input.

[0064] Any step, operation, or procedure described herein may be performed or implemented using one or more hardware or software modules, either alone or in combination with other devices. In one embodiment, the software module is implemented using a computer program product comprising a computer-readable medium containing computer program code, which is executable by a computer processor to perform any or all of the described steps, operations, or procedures.

[0065] The foregoing description of implementations of this application has been provided for illustrative and descriptive purposes. The foregoing description is not exhaustive and is not intended to limit this application to the exact forms disclosed. Various modifications and variations may exist in accordance with the foregoing teachings, or may arise from practice of this application. These embodiments were chosen and described to illustrate the principles of this application and its practical application, enabling those skilled in the art to utilize this application in various implementations and modifications to suit the specific purpose of the concept.

[0066] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0067] It can be further understood that, unless otherwise specified, "connection" includes both direct connections where no other components exist between the two parties and indirect connections where other components exist between them.

[0068] It is further understood that although the operations are described in a specific order in the accompanying drawings in the embodiments of this application, this should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all the operations shown to be performed to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0069] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the field of this application that are not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0070] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

[0071] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A novel nebulizer via endotracheal tube, characterized in that, It includes a drug delivery catheter (2), an automatic injection unit (1) and a control circuit (18). One end of the drug delivery catheter (2) is connected to the automatic injection unit (1). The middle part of the drug delivery catheter (2) is inserted into a four-way connector and can be selectively fixed to any position along the axis of the drug delivery catheter (2) through an interface (3) with a knob. The four-way connector includes: Side connection port (4) is used to connect the breathing circuit of the ventilator (17); A side opening (5) for inserting a fiberoptic bronchoscope to position the drug delivery catheter (2) within the patient's airway; and The other end is a connector (6) for connecting the endotracheal tube (7); The drug delivery catheter (2) passes through the tracheal catheter (7), and its distal end is provided with an atomizing nozzle (12). The atomizing nozzle (12) includes a drug change check valve (13), a drug addition check valve (14), multiple side spray holes (15) and multiple end spray holes (16). The control circuit (18) is communicatively connected to the automatic injection unit (1). The control circuit (18) is used to receive ventilator monitoring parameters output by the ventilator (17). The ventilator monitoring parameters include at least airway pressure parameters, exhaled volume parameters, and end-expiratory carbon dioxide waveform parameters. The control circuit (18) is used to identify the inspiratory and expiratory phases in the current respiratory cycle according to the ventilator monitoring parameters and determine the inspiratory start time; after identifying the inspiratory start time, the control circuit (18) assigns the drug administration task to be performed to the current respiratory cycle to obtain the target drug administration dose corresponding to the current respiratory cycle; the control circuit (18) generates the step-driven control sequence of the automatic injection unit (1) according to the target drug administration dose corresponding to the current respiratory cycle, so as to perform drug delivery in the inspiratory phase and stop or limit drug delivery in the expiratory phase; When the control circuit (18) identifies the inspiratory phase and the expiratory phase, it makes a joint judgment based on the trend of airway pressure change, the relationship between exhaled volume change and the relationship between end-expiratory carbon dioxide waveform change, and introduces a hysteresis retention mechanism when switching phases.

2. The novel nebulizer via endotracheal tube according to claim 1, characterized in that, The drug delivery catheter (2) is disposed inside the four-way connector and extends along the inner lumen of the tracheal tube (7), and the atomizing nozzle (12) covers the tail of the drug delivery catheter (2).

3. The novel nebulizer via endotracheal tube according to claim 2, characterized in that, The dosing check valve (14) is located inside the atomizing nozzle (12) on the side near the four-way connector, so that the liquid medicine is output unidirectionally from the proximal end to the distal end; The plurality of lateral spray holes (15) are arranged around the side wall of the atomizing nozzle (12); The plurality of end-point nozzles (16) are located at the end of the atomizing nozzle (12) away from the dosing check valve (14).

4. The novel transtracheal nebulizer according to claim 3, characterized in that, The one-way valve (13) for changing medicine is located inside the atomizing nozzle (12) on the side near the end-direction nozzle (16); During the dressing change process, the automatic injection unit (1) performs a back suction action through the drug delivery conduit (2), causing the dressing change one-way valve (13) to open under negative pressure, so that the gas in the tracheal conduit (7) is injected back into the atomizing nozzle (12).

5. The novel transtracheal nebulizer according to claim 4, characterized in that, The ventilator (17) collects ventilator monitoring parameters in real time and sends them to the control circuit (18) through the data interface. The ventilator monitoring parameters include airway pressure, lung compliance, exhaled air volume, gas retention parameters, blood oxygen saturation, oxygenation index and end-tidal carbon dioxide waveform parameters. The control circuit (18) outputs a drug change command or a drug addition command to the automatic injection unit (1) based on the drug dosage information given by the expert diagnostic system.

6. The novel transtracheal nebulizer according to claim 5, characterized in that, The control circuit (18) executes the stepper motor injection control algorithm. After inputting the dosage and administration time on the display interface, it controls the stepper motor to drive the automatic injection unit (1) to complete the precise administration according to the acceleration phase, the constant speed phase and the deceleration phase. in, When the total number of pulses meets the pulse allocation for the acceleration and deceleration phases, the control circuit (18) outputs a three-segment pulse control sequence according to the preset target speed. When the total number of pulses is insufficient to complete the acceleration and deceleration phases at the preset target speed, the control circuit (18) recalculates the maximum achievable speed based on the total number of pulses and outputs a pulse control sequence based on the recalculated maximum achievable speed.

7. A control method for a novel nebulizer via endotracheal tube, characterized in that, The method, applied to the novel transtracheal nebulizer according to any one of claims 1 to 6, comprises: The ventilator monitoring parameters output by the ventilator (17) are obtained, and the ventilator monitoring parameters are preprocessed by the control circuit (18) to obtain a monitoring parameter sequence for determining the respiratory cycle; The control circuit (18) identifies the inspiratory and expiratory phases in the current respiratory cycle based on the monitoring parameter sequence and determines the inspiratory start time; When the control circuit (18) identifies the inspiratory phase and the expiratory phase, it makes a joint judgment based on the trend of airway pressure change, the relationship of exhaled volume change and the relationship of end-expiratory carbon dioxide waveform change, and introduces a hysteresis retention mechanism during phase switching to suppress false switching caused by short-term fluctuations. After identifying the inhalation start time, the control circuit (18) assigns the drug administration task to be performed to the current respiratory cycle and obtains the target drug administration dose corresponding to the current respiratory cycle. The control circuit (18) generates a step-driven control sequence for the automatic injection unit (1) based on the target dosage corresponding to the current respiratory cycle, so as to perform drug delivery during the inspiratory phase and stop or limit drug delivery during the expiratory phase.

8. The control method according to claim 7, characterized in that, The preprocessing of the ventilator monitoring parameters includes: Time alignment of airway pressure parameters and end-tidal carbon dioxide waveform parameters; For monitoring parameters that fluctuate, perform filtering or remove abnormal sampling points; Candidate points for respiratory cycle boundaries are extracted based on the processed parameter sequence.

9. The control method according to claim 7, characterized in that, The process of assigning the drug delivery task to be performed to the current respiratory cycle includes: Determine the target dosage for the current respiratory cycle based on the total dosage, dosage time, and current respiratory cycle information; Based on the residual volume parameters of the drug delivery conduit (2) and the atomizing nozzle (12), a compensatory allocation is performed for the first drug delivery cycle or the first drug delivery cycle after drug change; Furthermore, when generating the step-driven control sequence, the control circuit (18) prioritizes the allocation of the target dosage corresponding to the current respiratory cycle to be executed in the first part of the inspiratory phase, and then allocates the remaining dosage to be executed or not executed in the second part of the inspiratory phase, so that the dosage intensity in the first part of the inspiratory phase is higher than the dosage intensity in the second part of the inspiratory phase.

10. The control method according to claim 7, characterized in that, The step-drive control sequence for generating the automatic injection unit (1) includes: Based on the propulsion volume corresponding to a unit pulse, the target dosage for the current respiratory cycle is converted into the target number of pulses; The target pulse count is distributed across multiple consecutive time periods based on the start time of the inspiratory phase, the first half of the inspiratory phase, and the last half of the inspiratory phase. Within each time period, the pulse frequency is output according to the control methods of acceleration, constant speed, and deceleration; When a medication change command is detected, the control circuit (18) controls the automatic injection unit (1) to perform a back suction action, so that the medication change check valve (13) opens under negative pressure, and performs a pre-filling action according to the residual volume parameters after back suction. When abnormal airway pressure, abnormal decrease in exhaled air volume, increased gas retention, or abnormal end-tidal carbon dioxide waveform are detected, the control circuit (18) stops the pulse output of the current dosing cycle and performs downgrade control or pause control for subsequent dosing cycles.

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