AU2016339393A1

AU2016339393A1 - Expectoration system

Info

Publication number: AU2016339393A1
Application number: AU2016339393A
Authority: AU
Inventors: Haibo BAI; Guang HAN; Hengqian XU; Qingbin XU
Original assignee: Ruxin Beijing Medical Systems Co Ltd
Current assignee: Ruxin (beijing) Medical Systems Co Ltd
Priority date: 2015-10-12
Filing date: 2016-09-26
Publication date: 2018-05-24
Anticipated expiration: 2036-09-26
Also published as: WO2017063498A1; TW201713373A; JP2018531100A; JP6715924B2; AU2016339393B2; CN105343944A; KR102135746B1; KR20180079321A; CN105343944B

Abstract

An expectoration system comprises an expectoration pipe (20) comprising a throttling device (21) and a balloon valve (19); an expectoration machine (1), comprising a main pipe assembly (15), an air pump assembly (2) and a control system (8). The main pipe assembly (15) comprises a fan (16) and a shutter valve (17). The air pump assembly (2) comprises a first air pump (6) and a second air pump (3). The control system (8) comprises a first sensor (12) for measuring an air pressure of the throttling device (21), and comprises a microcomputer control unit. The microcomputer control unit determines a patient being in an exhaling or inhaling stage by means of an air pressure difference detected by the first sensor (12); during expectoration, the first air pump (6) supplies air to the balloon valve (19) to disconnect a respirator air path, the fan (16) and shutter valve (17) are opened to control the second air pump (3) to supply air to the throttling device (21), and a respirator does not stop running in the expectoration sage.

Description

TECHNICAL FIELD

The present disclosure relates to a medical care apparatus, and more particularly to an inexsufflation system.

BACKGROUND ART

Medical ventilator is a life-critical support device for patients who suffer respiratory failures due to various causes, including acute respiratory distress syndrome (ARDS), severe acute pulmonary edema and asthma, and respiratory insufficiency, and for those in major surgeries. For a patient on a ventilator, it is very important to clear sputum timely and effectively. If sputum in the respiratory tract fails to be timely expelled, thick sputum and sputum scabs are prone to being deposited to clog the bronchial lumen, which seriously affects the patient’s ventilatory function, exacerbates the respiratory failure, and even induces a secondary pulmonary collapse. Sputum is also a breeding ground for bacteria. Once the patient’s respiratory organs are infected by bacteria, a ventilatorassociated pneumonia (VAP) would easily develop in the patient. However, a mechanically ventilated patient always cannot eject sputum spontaneously due to his/her loss of coughing function, severe lung function failure, and respiratory muscle weakness, etc., such that secretions will grow significantly. In addition, since mechanically ventilated patients are mostly in a consciousness disorder and a general failure state, their expectoration function by coughing is deteriorated, which aggravates their original respiratory diseases and respiratory failures. Tracheal intubation and tracheotomy will damage the natural barrier of the laryngeal part of pharynx, which weakens the cleaning function of airway cilia and also weakens the reflex mechanism of coughing and expectorating. Therefore, for mechanically ventilated patients, continuous and effective sputum clearance is critical to prevent airways from being clogged and to maintain mechanical ventilation.

A conventional sputum suctioning method is catheter suction, where a narrow-gauged catheter is used to be inserted into a patient’s airway via an endotracheal or tracheostomy tube. By continuous negative pressure suctioning within the narrow-gauged catheter, the sputum will be sucked out from the patient’s body. When the catheter comes into close proximity with secretions, the secretions will be suctioned away. However, this sputum suction approach has appreciable drawbacks. Firstly, it is an invasive sputum suction, such that insertion and removal of the catheter easily hurts the airway, while scarring of the airway further increases production of airway secretions. A consequence would be that more sputum is produced with suctioning. Meanwhile, this approach will also exacerbate hypoxemia; if the sputum cannot be timely cleared, there would be a higher potential hazard of infection and hemorrhage. For most patients, this approach is a very painful experience.

Another approach of clearing airway secretions from a mechanically ventilated patient is to use a typical inexsufflator, e.g., the Philips CoughAssist® device. When it performs inexsufflation, the patient’s lungs are first insufflated to near maximum tidal capacity, and then rapidly and suddenly exsufflated by sucking air out of the lungs at a highest velocity. Because air is expelled from the patient’s lungs at an extremely high velocity, the airflow may carry the secretions up and out of the patient’s airways with a high velocity airflow, thereby fulfilling the objective of clearing patient secretions. The way it clears the secretions is substantively a simulated expectoration. This inexsufflator may be interfaced with the patient’s airway via an endotracheal or tracheostomy tube or a facial mask. This inexsufflation approach may be preferred over the above-mentioned catheter suction due to its non-invasive nature. Besides, the inexsufflator generates an airflow within the entire diameter and length of the patient's functional airway and at a high flow rate, thus causing expulsion of secretions from the entire airway. In contrast, catheter suction generates an airflow only within the narrow suction catheter, and at a relatively lower flow rate. Because of its physical dimensions, the suction catheter is capable of reaching only the larger airways, but not the small, more peripherally branched airways. Besides, when the catheters are inserted into the airways, the branching morphology of the left and right bronchi is such that the suction catheters usually enter the right mainstem bronchus, but usually miss the left mainstem bronchus. During catheter suction, much of the patient's functional airway is therefore not exposed to the catheters and suction airflow, and consequently only a speck of sputum is sucked away near the suction catheters. In contrast, by inexsufflation with the inexsufflator, the secretions will be wholly removed by the airflow within the patient’s airways.

However, the inexsufflator has its own drawbacks. For example, when performing inexsufflation on a mechanically ventilated patient, it is required to first disconnect a ventilation tubing between the ventilator and the patient and then connect the inexsufflator with the patient to enable the inexsufflation procedure. However, frequent disconnection of the ventilation tubing between the ventilator and the patient might cause exacerbation of the condition of the mechanically ventilated patient on the ventilator, particularly for a critically ill patient. The inexsufflator adopts a time-cycled cycling mechanism to terminate the patient’s phase of inhalation, which may present some disadvantages, because volumecycled or flow-cycled cycling mechanisms are usually the safest and most efficient methods for ventilating patients. Furthermore, the inexsufflator cannot maintain a positive end expiratory pressure (PEEP), such that its air pressure in the airway at an end segment of exsufflation may only be approximately equal to the atmospheric pressure. However, the PEEP plays an important role in treating the ARDS, non-cardiogenic pulmonary edema, and pneumorrhagia, which meanwhile may encourage sputum removal. The inexsufflator is not suitable for patients with the above symptoms. In addition, the inexsufflator does not have an alarm system equipped to a life support device, such that safety of its use cannot be guaranteed.

A conventional inexsufflator uses the same tubing to carry both exsufflatory airflow and insufflatory airflow. The exsufflatory airflow contains the patient’s secretions that possibly carry a large number of bacteria. These secretions are deposited in the tubing, repeatedly exposed to the patient’s insufflated airflow, carrying a reinfection risk to the patient.

Furthermore, the inexsufflator uses a same turbine for insufflation and exsufflation. During the insufflation and exsufflation, the turbine is directly exposed to potentially infected airway secretions. If a same inexsufflator is shared by different patients, the service life of the turbine will be potentially reduced, while a potential hazard of interpatient infection will increase.

The patent W02007054829 discloses a combined ventilator inexsufflator to assist with respiration, coughing and secretion removal in a patient. Compared with the Phillips CoughAssist® device, in that patent, the air source for positive pressure ventilation to the patient does not employ a turbine inside the conventional inexsufflator but employs a ventilator for mechanically ventilating the patient. Different channels are available for insufflating and exsufflating the patient; and a switching valve is provided for the insufflation channel and the exsufflation channel, respectively. When the ventilator ventilates the patient normally, the switching valve provided on the insufflation channel is open, while the switching valve on the exsufflation channel is closed. When the patient finishes the inhalation and will enter the exhalation phase, the valve on the exsufflation channel is open, and the inexsufflator starts exsufflation. At the end of the exsufflation, the valve on the exsufflation channel is closed, while the valve on the insufflation channel is opened, and then the patient enters the inhalation phase, so on and so forth.

Compared with the Phillips CoughAssist® device, the W02007054829 patent does not require disconnecting the patient from his/her ventilator; therefore, the patient will continuously receive ventilator treatment. A temporary pause is even disadvantageous particularly for those that need PEEP provided by the ventilator. PEEP facilitates exhalation. Meanwhile, because the Phillips CoughAssist® device requires disconnecting from the ventilator for inexsufflation, the exsufflation can only be made with a certain interval; a consequence is that the sputum cannot be timely cleared. In contrast, the W02007054829 patent does not require disconnecting from the ventilator for inexsufflation, which may perform inexsufflation instantly at any time. Besides, different channels are provided for insufflating and exsufflating the patient, which reduces the reinfection hazard of the patient; by employing the ventilator and the negative pressure turbine inside the inexsufflator for performing positive pressure ventilation and negative pressure exsufflation to the patient, inter-patient infection is avoided and the service life of the turbine is prolonged.

However, the W02007054829 invention still has some problems in implementation, e.g., too high noise, poor heat radiation; the inexsufflation will affect the ventilator’s operation and even will issue a false alarm; therefore, the system has a potential safety issue. Besides, it has a relatively poor clinical adaptability. The present disclosure effectively solves the problems existing in the W02007054829 invention, which is an engineering implementation of the schematic solution of the W020072007054829 invention with further differentiation, enrichment and perfection.

DISCLOSURE OF INVENTION

To address the foregoing problems in the prior art, the present disclosure provides an inexsufflation system, comprising: an inexsufflator and an inexsufflation tubing, the inexsufflation tubing including a throttling device and a balloon valve, wherein the balloon valve is a two-way valve, one port of which is a ventilator port that is connected to a ventilator via the throttling device, the other port of which is branched into two, with one branch being an inexsufflator branch that is connected to the inexsufflator, and the other branch being a patient port that is connected to the patient;

the inexsufflator including a main tubing assembly, an air pump assembly, and a control system, wherein the main tubing assembly comprises a turbine that generates negative pressure and a shutter valve that opens during inexsufflation; the air pump assembly comprises a first air pump that supplies gas to the balloon valve and a second air pump that supplies gas to the throttling device; and the control system, which is configured for controlling the main tubing assembly and the air pump assembly, comprises a first sensor for measuring air pressure at the throttling device, and a microcomputer controlling unit;

and wherein the microcomputer control unit determines whether the patient is in an inhalation phase or an exhalation phase based on an air pressure difference detected by the first sensor, such that when the patient is transiting from the inhalation phase to the exhalation phase, the microcomputer control unit controls the first air pump to supply gas to a balloon of the balloon valve to disconnect an air path from the ventilator port to the patient port, and the control system switches on the turbine and the shutter valve to assist the patient to expectorate; meanwhile, the microcomputer control unit controls a second air pump to supply gas to the throttling device, such that during the inexsufflation procedure, the ventilator does not stop working.

The inexsufflation system provided by the present disclosure may work in lull automation; when use in coordination with a ventilator, it does not require the ventilator to pause and thus does not affect normal working of the ventilator.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows an air path principle diagram of a fully automated inexsufflation system according to the present disclosure.

Fig. 2 shows a stress analysis diagram of a balloon valve.

Fig. 3 shows an air path connection diagram of an air path assembly.

BEST WAY OF CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings, wherein like parts are indicated by like reference numerals.

Fig. 1 describes in detail an air path principle of a fully automated inexsufflation 20 system according to the present disclosure. The fully automated inexsufflation system comprises two parts: an inexsufflator 1 and an inexsufflation tubing 20. The inexsufflation tubing 20 is a disposal article, which, for example, may be made of medical plastics.

The inexsufflator 1 mainly functions to provide a negative pressure producing a high speed airflow and meanwhile monitor data such as pressure, flow, tidal capacity, and time of the whole system, and to perform analysis, determination, and calculation based on results of the monitoring, so as to implement an effective control of the system, and to trigger and pause inexsufflation.

Core parts of the inexsufflation tubing 20 include a throttling device 21 and a balloon valve 19. The inexsufflation tubing 20 forms an air path communication between a patient, a ventilator, and the inexsufflator 1, provides interfaces for various pressure and flow sensors to collect data, and meanwhile implements switching between a ventilator-patient air path and an inexsufflator-patient air path.

Specifically, an interface A and an interface B are provided on the throttling device 21 of the inexsufflation tubing 20. The interface A is connected to a second air pump 3 of an air pump assembly 2 (as will be described infra) in the inexsufflator 1, the second air pump 3 may supply gas to the interface A. The interface B is connected to a third air pump 5 of the air pump assembly 2 in the inexsufflator 1, which third air pump 5 may supply gas to the interface A. Additionally, the interfaces A and B are connected to two input ports of a pressure different sensor 12 (first sensor) in the inexsufflator 1, respectively, substantively constituting a pressure difference flow meter. Optionally, the interface A is connected to the pressure sensor 12, and the interface B is connected to a pressure sensor 11 (second sensor), wherein pressures at the two interfaces are detected by the two sensors, respectively, such that the pressure sensor 12 and the pressure sensor 11 substantively constitute a pressure difference flow meter.

The balloon valve 19 is a two-way valve, comprising a ventilator port connected to a ventilator, the other port being branched into two, with one branch being an inexsufflator port that is connected to the inexsufflator, and the other branch being a patient port that is connected to a patient. A channel between the ventilator port and the patient port is constantly open, for supplying gas to the ventilator. However, the air path may be closed by the balloon valve 19. A manner of implementing closing the air path is to provide a balloon inside the balloon valve 19; such that when the balloon is inflated to dilate, the balloon will bulge to block a valve gate, thereby disconnecting the ventilator-patient air path. A channel between the inexsufflator port and the patient port is constantly open;

however, because the shutter valve 17 is constantly closed, the ventilator will not be affected in supplying gas to the patient. The shutter valve 17 is only opened when the inexsufflator is working. Moreover, when the inexsufflator is working, it inflates the balloon inside the balloon valve 19 to close the ventilator-patient air path so as not to affect the inexsufflator’s operation. Upon end of the inexsufflation, the shutter valve 17 is closed, and the balloon inside the balloon valve 19 is deflated, such that the volume of the balloon shrinks, and a relatively large gap is generated between the valve gate and the balloon, via which gap the airflow may pass, thereby implementing a function of conducting the air path. In addition, gas supply to the balloon valve 19 is made by a first air pump 6 of the air pump assembly 2 in the inexsufflator 1, wherein the gas supply of the first air pump 6 is controlled by a solenoid valve 4 in the air path assembly 22 (as will be described infra).

Preferably, when the balloon valve 19 is deflated, the gas in the balloon valve 19 is not discharged into air, but into the main respiratory tubing, a purpose of which is that: if the space inside the balloon valve 19 is directly communicative with the air, spontaneous respiration of some patients might cause a negative pressure environment in the main respiratory tubing; under the action of the pressure difference between the atmospheric pressure and the negative pressure in the main respiratory tubing, the balloon valve 19 which is softer and thinner may otherwise disconnect the respiratory tubing or narrow the respirator tubing, thereby endangering life of the patient (see Fig. 2). Meanwhile, after each inexsufflation, the gas discharged from the balloon valve 19 may also sweep a measuring and controlling tubing of a pressure sensor 9 (a third sensor) that detects pressure at the patient port (position C in Fig. 1), to prevent water drops or sputum from being deposited in the measuring and controlling tubing of the sensor 9, which would otherwise affect the sensor’s operation.

Hereinafter, the inexsufflator 1 will be described in detail. The inexsufflator 1 comprises: an air pump assembly 2, an air path assembly 22, a main tubing assembly 15, a control system 8, and a noise reduction system 18.

The air pump assembly 2 comprises three micro air pumps: a first air pump 6, a second air pump 3, and a third air pump 5. The first air pump 6 supplies gas to the balloon of the balloon valve 19. The second air pump 3 supplies gas to the interface A of the throttling device 21, and the third air pump 5 supplies gas to the interface B of the throttling device 21. The second air pump 3 and the third air pump 5 play two roles. The first role is to avoid the ventilator from alarming when the inexsufflator is working normally. After the inexsufflation commences, because the ventilator air path is disconnected, no gas exhaled by the patient enters a ventilator exsufflation circuit, such that the ventilator will misidentify a patient suffocation, tubing decannulation or other abnormal conditions and thereby will issue an alarm. At this point, the second air pump 3 and the third air pump 5 will provide a gas flow with enough amount. The gas flow enters a ventilator inexsufflation circuit channel via the throttling device 21 and sweeps the ventilator inexsufflation circuit channel, thereby avoiding the ventilator from alarming. In addition, during actual use, the ventilator needs to be serially connected with a humidified bottle in the tubing to guarantee humidification of the gas or oxygen inhaled by the patient; a consequence is that much liquid-state water will be condensed at any time in the respiratory tubing, and the gas exhaled by the patient will also contain water. Further, during the process of suctioning sputum from a patient, the sputum sucked out is also possible to be attached or adhered onto the tubing. Such a complex tubing environment is rather adverse to accurate signal detection by various sensors, particularly when the liquidstate water or sputum is deposited in the extremely narrow-gauged tubing for measuring and controlling. Therefore, the second role played by the second air pump 3 and the air pump 5 is to periodically sweep the tubing between the pressure sensor 11, the pressure difference sensor 12, and the throttling device 21, to prevent the liquid-state water or sputum from affecting the sensor’s operation. In this embodiment, a power element for generating a sweeping gas is not limited to an air pump or a micro air compressor, which may also employ a turbine or a high-pressure storage tank for storing gas. One, or more, or a combination of the power elements or energy storage elements is used, or the gas discharged from the turbine is collected to be blown back to the inexsufflation circuit of the ventilator to replace the purging. In this embodiment, two high-pressure second air pumps 3 and 5 are adopted in parallel to supply gas so as to satisfy a demand of instantaneous large flow. Optionally, one air pump may also be adopted to supply gas to both interface A and interface B of the throttling device 21 simultaneously.

The air path assembly 22 functions to conduct the air path between the inexsuflflator 1 and the inexsufflation tubing 20 and control a connection therebetween. A core component of the air path tubing 22 is a solenoid valve 4. The solenoid valve is preferably two9 position three-way, but not limited to that. For example, it may be two-position two-way, four-way, five-way, or three-position, etc. The solenoid valve 4 controls the first air pump 6. The first air pump 6 functions to supply and discharge gas to and from the balloon valve 19 under the control of the two-position three-way solenoid valve 4. The air path assembly

22 may further comprise another two-position three-way solenoid valve 7, which belongs to a backup solenoid valve, playing a role of dual safety protection, i.e., when the twoposition three-way solenoid valve 4 fails, such that the gas inside the balloon valve 19 cannot be discharged, the ventilator tubing cannot be conducted, and the patient cannot be mechanically ventilated, the two-position three-way solenoid valve 7 will be energized to be opened so as to discharge the gas in the balloon valve 19.

The main tubing assembly 15 comprises a shutter valve 17, a mass flow meter 14, a pressure sensor 13 (the fifth sensor) and a turbine 16. Preferably, because high decibel rotary noise and eddy noise will be produced when the negative pressure turbine 16 is working to discharge, the main tubing assembly 15 further comprises a noise reduction system 18 for effectively reducing the impact of noise on the environment. The turbine 16 is for producing a negative pressure required for inexsufflation. The pressure sensor 13 instantly detects the pressure on the turbine 16 and transmits it to the control system 8. The turbine 16 for example may be a centrifugal, axial-flow type turbine, but not limited to a turbine, which may include any power element that may produce negative pressure, e.g., a vacuum pump, a vacuum generator, etc. The mass flow meter 14 detects a suctioning flow during inexsufflation and provides it to the control system 8, when the mass flow meter 14 detects that the suctioning flow is approximate to zero or when needed, by the control system 8 closes the shutter valve 17 so as to disconnect the inexsufflation circuit. The mass flow meter 14 may be a pressure-difference type, a thermal type, a worm-gear type, a supersonic type, or any other type, but preferably the pressure-difference type or thermal type. The shutter 17 is constantly closed, which is only opened by the control system 8 when the inexsufflator is working. Meanwhile, it has a function of quick open and quick close to implement an airflow disturbance; in this way, the effect of inexsufflation is enhanced.

The control system 8 comprises a microcomputer control unit, a human-machine interface (for setting parameters of the fully automated inexsufflation system), and various kinds of pressure or pressure-difference sensors. The control system 8 collects various parameters acquired by the sensors and controls output of these parameters to other parts (e.g., the shutter valve 17 and the solenoid valve 4) as well as controlling human-machine interactions.

The control system 8 comprises a pressure sensor 11 and a pressure sensor 12; the pressure sensors 11 and 12 monitor in real time the pressures at two sides of the throttling device 21 as well as the pressure dilference therebetween, respectively, i.e., the pressure sensor 11 detects the pressure at interface A of the throttling device 21, and the pressure sensor 12 detects the pressure at interface B of the throttling device 21; they also transmit the data to the microcomputer control unit. As mentioned above, the pressures at the interface A and the interface B may also be detected by only one pressure-dilference sensor 12, respectively. The purpose for the pressure sensors 11 and 12 to monitor the pressures of the throttling device 21 is determine whether the patient is in an inhalation phase or an exhalation phase, so as to prepare data for whether to turn on the inexsufflator.

Preferably, the control system 8 further comprises a pressure sensor 9. The pressure sensor 9 detects in real time the pressure at a patient port (position C in Fig. 1) of the balloon valve 19 and transmits the data to the microcomputer control unit.

In actuality, what are detected by the pressure sensor 9 and the pressure sensor 11 are the pressures at two sides of the balloon valve 19. During a normal respiration phase, if pressure values at two sides of the balloon valve 19 are greater than a threshold (e.g., a 5cm water column), the microcomputer control unit will alarm. The purpose of this practice is that: if the solenoid valve 4 fails, the balloon valve 19 will fail to be opened and gas cannot be discharged; besides, if the dual-protection solenoid valve 7 fails to enable the balloon valve to discharge gas, the ventilator tubing will be blocked, such that gas cannot be supplied to the patient; then the control system 8 will alarm an operator to immediately check the system, thereby providing a third protection to the patient.

Preferably, the control system 8 further comprises a pressure sensor 10 (the fourth sensor) for detecting the pressure at an outlet of the first air pump 6. The pressure sensor 10 may be arranged between the first air pump 6 and the solenoid valve 4 or between the solenoid valve 4 and the balloon valve 19. To prevent the pressure at the outlet of the first air pump 6 from being too high, which blocks to bum down a motor or blows the balloon of the balloon valve 19 to be broken, one solution is to add a gas storage tank with a small hole thereon, such that gas may be slowly let out, thereby preventing the pressure at the air pump outlet from being too high. More preferably, the pressure sensor 10 (the second pressure sensor) is additionally provided at the outlet of the first air pump 6. By automatically adjusting a rotating speed of the first air pump 6 using a PWM approach based on the pressure at the outlet of the first air pump 6 (i.e., increasing the rotating speed of the air pump when the pressure at the air pump outlet is low; decreasing the rotating speed of the pump or even stopping it when the outlet pressure is high), a constant pressure is maintained at the outlet of the first air pump 6, thereby guaranteeing safety of the air pump. Meanwhile, the size of the device is reduced, the energy consumption is lowered, and the system reliability of enhanced.

Fig. 3 shows an exemplary connection relationship diagram of the air path assembly

22. The air path assembly 22 further comprises 10 adapters: first adapter 207, second adapter 206, third adapter 204, fourth adapter 203, fifth adapter 258, sixth adapter 205, and four adapters connected with the inexsufflation tubing 20, namely: seventh adapter 226, eighth adapter 228, ninth adapter 229, and tenth adapter 230.

Specifically, one end of the first adapter 207 is connected to the second air pump 3, and the other end thereof is connected to the seventh adapter 226 and further connected to interface A of the throttling device 21 in the inexsufflation tubing 20. Compressed air outputted by the second air pump 3 will be outputted to the interface A of the throttling device 21 via the first adapter 207 and the seventh adapter 226, thereby implementing that the second air pump 3 blows the interface A. The second adapter 206 is communicative with an input port of the pressure difference sensor 12, via which path the pressure difference sensor 12 may collect pressure data at point A on the throttling device 21. The third adapter 204 is communicative with another input port of the pressure difference sensor 12 (or communicative with the pressure sensor 11), and the third adapter 204 is connected to interface B of the throttling device 21 via the ninth adapter 229; via this path, the pressure difference sensor 12 may collect pressure data at the interface B on the throttling device 21. Likewise, the fourth adapter 203 is communicative with the third air pump 5, and then connected to interface B of the throttling device 21 in the inexsufflation tubing 20 via the ninth adapter 229, thereby implementing that the third air pump 5 blows the interface B.

The fifth adapter 258 is connected to the first air pump 6 and a first gate (see (1) in Fig. 3) of the solenoid valve 4. The eighth adapter 228 is connected to the second gate (see (2) in Fig. 3) of the solenoid valve 4 and is further connected to the balloon valve 19. The sixth adapter 205 is connected to the third gate (see (3) in Fig. 3) of the solenoid valve 4 and the pressure sensor 9. The tenth adapter 230 is connected to gate (3) of the solenoid valve 4 and the patient port C. Substantively, the communication between the sixth adapter 205 and the tenth adapter 230 enables the pressure sensor 9 to monitor pressure at an end in the main respiratory tubing in proximity to the patient. It is very useful to detect the pressure at this portion, which, just as mentioned above, may be used as a basis for determining whether the main respiratory tubing is blocked. The compressed air outputted by the first air pump 6 enters the solenoid valve 4 from the gate (1) of the solenoid valve 4 via the fifth adapter 258.

When the solenoid valve 4 is deenergized, it may be seen from Fig. 3 that the gate (1) is closed, and the air path is thereby disconnected. After the solenoid valve 4 is energized, gate (1) and gate (2) are conducted. The gas flow flows out of the gate (2) of the solenoid valve 4. By direct communication between the eighth adapter 228 and the balloon valve 19, energizing the solenoid valve 4 enables the first air pump 6 to inflate the balloon valve

19, such that the balloon valve is thus closed to disconnect the ventilator tubing (see Fig.

2). When it is needed to deflate the balloon valve, the solenoid valve 4 is deenergized, and the gate (2) and the gate (3) of the solenoid valve 4 are conducted; the gas inside the balloon of the balloon valve is discharged through the eighth adapter 228, the gate (2) of the solenoid valve 4, and the gate (3) of the solenoid valve 4 to arrive at the tenth adapter

230. The tenth adapter 230 is communicative with a pressure collection port at an end of the disposal inexsufflation tubing 20 in proximity with the patient, such that the gas discharged from the balloon valve finally enters the main respiratory tubing via the pressure collection port. As to why the gas discharged from the balloon valve is not discharged into air but into the main respiratory tubing, it has been explained above.

As mentioned above, the solenoid valve 7 functions such that when the solenoid valve fails to switch due to some reasonthe balloon valve 19 cannot be deflated, which causes that the ventilator tubing is unexpectedly disconnected, the solenoid valve 7 may timely deflate the gas in the balloon timely, which guarantees safety of the patient. The work process is as such: when the solenoid valve 4 is deenergized, the main system detects that the balloon valve is not deflated, the solenoid valve 7 then will be energized, and the gas in the balloon valve will enter the first gate (gate (1) in Fig. 3) of the solenoid valve 7 via the eighth adapter 228; at this point, because the solenoid valve 7 is energized such that the first gate and the second gate ((2) in Fig. 3) are conducted, and the gas is discharged from the second gate of the solenoid valve 7 and enters the main respiratory tubing from the pressure detection port for the patient, thereby deflating the balloon valve.

As mentioned above, the inexsufflation system according to the present disclosure may work in an automated mode, i.e., an operator (generally a medical care staff) sets an interval time; once the time comes, the fully automated inexsufflator will enter a ready state, and the system starts detecting whether the patient satisfies an inexsufflation condition; in the case of satisfaction, the inexsufflation will commence. Another working approach is a manual mode, where the operator is usually a patient with a certain mobility; when the patient presses down a manual inexsufflation button, the inexsufflation does not start immediately, the fully automated inexsufflator enters a ready state, till the patient finishes inhalation and before the patient commences respiration, and an inexsufflation condition is met, then the inexsufflator only starts inexsufflation. The inexsufflation is not unconditionally. Without satisfying a certain condition, compulsory inexsufflation will not reach a desired effect and will possibly cause damages to the patient.

With reference to Fig. 1, when the inexsufflation is not performed, the control system monitors the pressures at the throttling device 21 collected by the sensors 11, 12 to monitor an inhalation flow. At this point, the balloon valve 19 is not inflated and is thus constantly open, while the shutter valve 17 is constantly closed. The ventilator continuously performs mechanical ventilation to the patient according to a set respiratory frequency. Onset of the inexsufflation may be manually triggered by the patient or automatically triggered according to a time interval (e.g., 5 minutes) set by then operator of the inexsufflator. The inexsufflation process is provided below:

1. After onset of the inexsufflation, the control system 8 turns on the turbine 16 inside the inexsufflator 1; a desired negative pressure will be produced in the tubing between the turbine 16 and the shutter valve 17. The negative pressure may range from -10cmH20 to 200cmH20, preferably from -50cmH20 to -150cmH20, and more preferably from 60cmH20 to -120cmH20. At this point, because the shutter valve 17 is closed, it will not cause any impact on the mechanical ventilation to the patient. The pressure sensor 13 instantly detects the turbine pressure and transmits it to the control system 8, and then the control system 8 may adjust the pressure of the turbine 16.

2. Now, the pressure sensor 11 inside the control system 8 monitors in real time the pressure at interface A of the throttling device 21, and the pressure difference sensor 12 monitors in real time the pressure at interface B of the throttling device 21; they transmit the data to the microcomputer control unit; the microcomputer control unit calculates the instant flow and pressure in the inexsufflation tubing 20, analyzes and determines whether the patient is in an inhalation phase or an exhalation phase, and captures a transition time point when the inhalation ends and the exhalation is to commence; when the patient is at this transition time point, the control system 8 turns on the first air pump 6; then the twoposition three-way solenoid valve 4 is energized to conduct the air path between the first air pump 6 and the balloon valve 19; the balloon valve 19 is inflated to be closed, which disconnects a ventilation line of the ventilator to the patient; almost at the same time, the constantly closed shutter valve 17 is rapidly opened by the control system 8, such that the negative pressure tubing of the turbine 16 is communicated with the patient’s airway. This will result in a rapid and sudden exhalation flow ejected from the patient’s lungs. Relevant practices and theoretical studies prove that when the flow is greater than 170L/Min, effective inexsufflation will be enabled. This flow is approximately equal to a normal coughing of a normal person. At this point, because the balloon valve 19 is closed, the ventilator will not be exposed to the negative pressure of the turbine. However, for some ventilators that have a function of detecting a patient’s exhalation flow, they will possibly alarm. Therefore, at the instant when the balloon valve 19 is closed, the second air pumps 3 and 5 in the air pump assembly 2 will start operation in the meanwhile. The produced gas will enter the respiratory tubing through interface A and interface B of the throttling device 21, respectively, flowing towards the inexsufflation circuit of the ventilator, thereby acting as the patient’s exhalation flow to avoid ventilator alarm.

3. When the gas flowing out from the patient’s lungs is discharged in the air through the shutter valve 17, the flow meter 14, the turbine 16, and the noise reduction system 18, the flow meter 14 detects the patient’s exhalation flow and transmits data to the microcomputer control unit; when it is detected that the patient’s exhalation flow is approximately zero, the microcomputer control unit closes the shutter valve 17; meanwhile, the two-position three-way solenoid valve 4 is deenergized, and the balloon valve 19 starts being deflated. The gas inside the balloon valve 19 flows into the patient’s main respiratory tubing through the three-way solenoid valve 4; the balloon valve 19 is thus opened, and the ventilator is conducted to the patient. At this point, the patient starts inhalation, and the ventilator is triggered; the patient continues normal mechanical ventilation like before inexsufflation. This marks a completion of one inexsufflation.

It should also be noted that: theoretically, the inexsufflation pauses when the patient’s exhalation flow is approximately zero; however, because parts like the shutter valve and the balloon valve need a response time; if an instruction is issued when the exhalation flow is approximately zero, over-suctioning might occur, which will otherwise endanger the patient’s life. Therefore, during an actual operation process, the shutter valve and the balloon valve should be closed in advance, such that when the flow meter 14 detects that a gas flow through the shutter valve 17 is lower than a threshold, the microcomputer control unit closes the shutter valve 17. An ideal value of the threshold may be adjusted based on the hardware device of the inexsufflation tubing and the patient’s physiological characteristics, which, for example, may be set to 17L/Min or above.

Meanwhile, for a patient suffering ARDS and the like who needs a ventilation treatment with a high PEEP (Positive End Expiratory Pressure) value, the shutter valve may be closed even earlier. Therefore, in the case of closing in advance, the flow value as needed will be greater than 17L/Min, such that the intrapulmonic pressure of the patient is still maintained above the atmospheric pressure upon end of the inexsufflation, which prevents atrophy and collapse of pulmonary alveoli. This is also an important reason why the present inexsufflation system may be applied to patients with various kinds of conditions more widely than the Phillips CoughAssist® device in the background.

Through continuous repetition of the above process, the airway secretions of the patient may be gradually and effectively expelled out of the body from a deep layer of the lungs, and then the sputum may be aggregated by a sputum collection device having a negative pressure suctioning function and dumped or cleared periodically by a medical care staff.

As mentioned above, the inexsufflation system may work in an automated mode, i.e., an operator (generally a medical care staff) sets an interval time; once the time comes, the fully automated inexsufflator will enter a ready state, and the system starts detecting whether the patient satisfies an inexsufflation condition; in the case of satisfaction, the inexsufflation will commence. Another working approach is a manual mode, where the operator is usually a patient with a certain mobility; when the patient presses down a manual inexsufflation button, the inexsufflation does not start immediately, but enters a ready state like the fully automated inexsufflator. The turbine is started till the patient finishes inhalation. The inexsufflator starts inexsufflation only when the inexsufflation condition is met before the patient commences respiration.

The embodiments described above are only preferred embodiments of the present disclosure. Normal variations and substitutions made by those skilled in the art within the scope of the technical solution of the present disclosure should all be included within the protection scope of the present disclosure.

Claims

1. An inexsufflation system, comprising: an inexsufflator (1) and an inexsufflation tubing (20), the inexsufflation tubing (20) including a throttling device (21) and a balloon valve (19), wherein the balloon valve (19) is a two-way valve, one port of which is a ventilator port that is connected to a ventilator via the throttling device (21), the other port of which is branched into two, with one branch being an inexsufflator branch that is connected to the inexsufflator (1), and the other branch being a patient port that is connected to the patient;

the inexsufflator (1) including a main tubing assembly (15), an air pump assembly (2), and a control system (8), wherein the main tubing assembly (15) comprises a turbine (16) that generates negative pressure and a shutter valve (17) that opens during inexsufflation; the air pump assembly (2) comprises a first air pump (6) that supplies gas to the balloon valve (19) and a second air pump (3) that supplies gas to the throttling device (21); and the control system (8), which is configured for controlling the main tubing assembly (15) and the air pump assembly (2), comprises a first sensor (12) for measuring air pressure at the throttling device (21), and a microcomputer controlling unit;

and wherein the microcomputer control unit determines whether the patient is in an inhalation phase or an exhalation phase based on an air pressure difference detected by the first sensor (12), such that when the patient is transiting from the inhalation phase to the exhalation phase, the microcomputer control unit controls the first air pump (6) to supply gas to a balloon of the balloon valve (19) to disconnect an air path from the ventilator port to the patient port, and the control system (8) switches on the turbine (16) and the shutter valve (17) to assist the patient to expectorate; meanwhile, the microcomputer control unit controls a second air pump (3) to supply gas to the throttling device (21), such that during the inexsufflation procedure, the ventilator does not stop working.

2. The inexsufflation system according to claim 1, wherein interface A and interface B are provided to the throttling device (21) along a gas supply flow direction of the ventilator, the air pump assembly (2) further comprises a third air pump (5), and the control system (8) further comprises a second sensor (11), moreover, the first sensor (12) is configured for detecting a pressure difference between the interface A and the interface B of the throttling device (21), and the second sensor (11) is configured for detecting an atmosphere pressure at the interface B of the

5 throttling device (21), and the second air pump (3) supplies gas to the interface A of the throttling device (21), and the third air pump (5) supplies gas to the interface B of the throttling device (21).

3. The inexsufflation system according to claim 2, further comprising an air path 10 assembly (22), the air path assembly (22) including a solenoid valve (

4) controlled by a microcomputer control unit, the solenoid valve (4) being connected between the first air pump (6) and the balloon valve (19), and the solenoid valve (4) controlling gas inlet and gas discharge of the balloon valve (19).

15 4. The inexsufflation system according to claim 2, wherein the control system (8) further comprises: a third sensor (9) configured for detecting pressure at the patient port of the balloon valve (19), such that when the microcomputer control unit calculates a pressure difference between the pressures detected by the second sensor (11) and the third sensor (9) is greater than a threshold, the microcomputer control unit alarms.

5. The inexsufflation system according to claim 1, wherein the main tubing assembly (15) further comprises a flow meter (14), the flow meter (14) being configured for detecting a gas flow flowing through the shutter valve (17), such that when the gas flow is lower than a threshold, the microcomputer control unit determines that the inexsufflation

25 ends and closes the shutter valve (17), the threshold being greater than 0.

6. The inexsufflation system according to claim 5, wherein the main tubing assembly (15) further comprises a fifth pressure sensor (13) for detecting a pressure of the turbine (16) , the microcomputer control unit adjusting a rotating speed of the turbine (16) based on the pressure detected by the fifth pressure sensor (13).

7. The inexsufflation system according to claim 3, wherein the air path assembly (22) further comprises: a first adapter (207), a second adapter (206), a third adapter (204), a

5 fourth adapter (203), a fifth adapter (258), a sixth adapter (205), a seventh adapter (226), an eighth adapter (228), a ninth adapter (229), and a tenth adapter (230), wherein:

one end of the first adapter (207) is connected to the second air pump (3), the other end thereof is connected to the interface A of the throttling device (21) via the seventh adapter (226),

10 the second adapter (206) is connected to the first sensor (12), the third adapter (204) is connected to the second sensor (11), one end of the fourth adapter (203) is connected to the third air pump (5), and the other end thereof is connected to the interface B of the throttling device (21) via the ninth adapter (229),

15 one end of the fifth adapter (258) is connected to the air pump (6), the other end thereof is connected to a first gate of the solenoid valve (4), the sixth adapter (205) is connected to a third gate of the solenoid valve (4) and connected to the third sensor (9), and one end of the eighth adapter (228) is connected to a balloon of the balloon valve 20 (19), the other end thereof is connected to a second gate of the solenoid valve (4), the tenth adapter (230) is connected to the third gate of the solenoid valve (4) and connected to the third sensor (9).

8. The inexsufflation system according to claim 7, wherein the air path assembly (22) 25 further comprises a backup solenoid valve (7), the first gate of the solenoid valve (7) being connected to the eighth adapter (228), the second gate of the solenoid valve (7) being connected to the tenth adapter (230); after the solenoid valve (7) is energized, the first gate and the second gate of the solenoid valve (7) are conducted, such that the gas in the balloon of the balloon valve (19) is discharged out via the eighth adapter (228) and the tenth adapter (230).

9. The inexsufflation system according to claim 8, wherein the sixth adapter (205) is connected to a respiratory tubing of the ventilator, such that the gas in the balloon of the

5 balloon valve (19) is discharged out into the respiratory tubing of the ventilator.

10. The inexsufflation system according to claim 4, wherein the control system (8) further comprises a fourth sensor (10) for detecting air pressure at an outlet of the first air pump (6), the fourth sensor (10) being provided at the outlet of the first air pump (6), such

10 that the microcomputer control unit adjusts the rotating speed of the first air pump (6) in a PWM manner based on the pressure detected by the fourth sensor (10), causing the first air pump (6) to output a constant pressure.

2/3 connection to connection to the ventilator the inexsufflator atmospheric pressure

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connection to the patient

Figure 2

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Figure 3