Cough assisting apparatus for assisting patient in coughing

Abstract

To provide a cough assisting apparatus for assisting a patient in coughing, and a ventilator having the cough assisting apparatus.SOLUTION: A cough assisting apparatus comprises: a blower with a suction opening, a blow-out opening, a drive motor, and a rotor coupled to the drive motor for conveying a gas from the suction opening to the blow-out opening depending on a motor speed of the drive motor; a pressure connection part; a patient connection part for connecting a patient interface; a connection channel fluidly connecting the pressure connection part to the patient connection part; a coupling device switchable between an air supply position and an exhaust position and is designed to be fluidly coupled to the suction opening at the exhaust position; a throttle device; a pressure sensor; and a control device for controlling an operation of the cough assisting apparatus.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cough assist device that assists a patient's cough and to an artificial respirator equipped with such a cough assist device. [Background technology]

[0002] Cough assist devices, also known as insufflator-exsufflator devices, can be used to enable or facilitate the expulsion of secretions from the airways and / or lungs of patients with impaired respiratory muscles. For this purpose, cough assist devices can apply alternating positive and negative pressure to the airways and / or lungs via an appropriate patient interface. This induces a cough or series of coughs in a controlled manner. The efficiency of secretion expulsion in a single coughing bout depends, among other things, on the maximum volumetric flow rate during exsufflation (also known as peak expiratory flow, or PCF for short). To allow good secretion expulsion, the PCF should be as high as possible. At the same time, excessive pressure peaks during exsufflation must be avoided. Summary of the Invention [Problem to be solved by the invention]

[0003] One object of the present invention is to provide a cough assist device that allows particularly efficient secretion evacuation, and another object of the present invention is to provide a ventilator equipped with such an improved cough assist device.

[0004] These problems are solved by the subject matter of the independent claims. Advantageous embodiments of the invention are set out in the dependent claims, the following description and the accompanying drawings. [Means for solving the problem]

[0005] A first aspect of the present invention relates to a cough assist device for assisting a patient's cough, the cough assist device comprising: an inlet, an outlet, a drive motor, and a blower having a rotor coupled to the drive motor for transferring gas from the inlet to the outlet in response to a motor rotation speed of the drive motor, a pressure connection, a patient connection for connecting a patient interface, a connecting channel fluidically connecting the pressure connection to the patient connection, a coupling device switchable between a delivery position and an exhaust position and designed to fluidly couple the pressure connection to the outlet in the delivery position and to fluidly couple the pressure connection to the inlet in the exhaust position, a throttle device switchable between an initial position and a throttle position and designed to narrow the connecting channel when switched to the throttle position, a pressure sensor designed to detect pressure present at the patient connection and generate a pressure signal indicative of the detected pressure, and a control device for controlling operation of the cough assist device. The control device is designed to perform the following delivery method: switching the coupling device to the delivery position; receiving (subsequently, or in response to switching the coupling device to the delivery position) a pressure signal, the pressure signal indicating the delivery pressure present at the patient connection as a detected pressure; determining the delivery pressure deviation between the delivery pressure and the delivery target pressure; controlling the drive motor to reduce the delivery pressure deviation; and (if controlling the drive motor), switching the throttle device to the throttle position to further increase the motor speed, and holding the throttle device in the throttle position.

[0006] Such a cough assist device allows a significant increase in PCF without requiring a more powerful blower or a faster changeover from the blowing position to the exhaust position. The throttle throttling has the effect of further increasing the flow resistance that the blower faces during the blowing, especially towards the end of the blowing. Pressure control leads to a corresponding increase in the motor speed. This allows a correspondingly increased volumetric flow rate to be provided in the next blowing, especially if the increased motor speed is maintained at least until the time of changeover to the exhaust position.

[0007] The cough assist device may comprise one or more electric or electrically controllable actuators for switching the coupling device and / or the throttle device, such actuators may be, for example, electric motors, electromagnets, piezoelectric elements, or a combination of at least two of these examples.

[0008] By "patient interface" it may be understood, for example, an oral mask, a nasal mask, a mouthpiece, or a tube. The patient connection may be fluidly connectable to the patient interface, for example, via a hose system.

[0009] By "drive motor" is meant in particular an electric motor.

[0010] The coupling device and the throttle device may each be an electrically switchable valve, the switching positions of the coupling device and / or the throttle device may be discrete switching positions, or the switching positions of the coupling device and / or the throttle device may be switching positions of a continuously adjustable valve.

[0011] "Initial position" can be understood as a position of the throttle device in which the connecting channel is not narrowed or is narrowed only slightly compared to the throttle position.

[0012] A "throttle position" can be understood as a position of the throttle device where the connecting channel is either completely narrowed, i.e. hermetically closed, or partially narrowed (e.g., at least 5% and / or up to 95% relative to the initial position), thereby allowing gas to continue to flow through the connecting channel. Depending on the embodiment, the switching speed at which the throttle device moves from the initial position to the throttle position can be constant or can vary over time according to a predetermined profile.

[0013] "Narrowing" can generally be understood as an increase in the flow resistance that opposes the blower during operation of the cough aid device. In that case, as already mentioned, the motor speed is increased by pressure control to compensate for the pressure drop caused by narrowing. In other words, a throttle device can generally be understood as a variable flow resistance.

[0014] The control device may include hardware and / or software components. For example, the control device may include a processor configured to execute a computer program for controlling the operation of the cough assist device. Furthermore, the control device may include a storage device and / or a data communication interface for wireless and / or wired data communication with peripheral devices. The control device may also be implemented exclusively as hardware, for example in the form of an ASIC or FPGA integrated circuit.

[0015] "Air supply pressure" can be understood as a positive or plus pressure relative to the respective atmospheric pressure.

[0016] A second aspect of the invention relates to a ventilator for invasive and / or non-invasive ventilation of a patient, the ventilator comprising an assistive cough device as described above and below, the ventilator being capable of providing additional ventilation functions for pressure and / or flow and / or volume controlled ventilation of the patient.

[0017] Various embodiments of the present invention are described below, which should not be construed as limiting the scope of the present invention.

[0018] According to one embodiment, the throttle device can be held in the throttle position at least until the coupling device is switched to the exhaust position, which allows for the provision of a correspondingly increased volumetric flow rate at the beginning of the exhaust, which can improve secretion evacuation.

[0019] According to one embodiment, the throttle device can be switched to and / or held in the throttle position during the insufflation method, taking into account the time course of the insufflation pressure and / or the time course of the motor rotation speed. In this way, a suitable switching point for switching the throttle device between the initial position and the throttle position can be determined depending on the current operating conditions of the cough aid device. Alternatively, the switching point can be fixed, for example depending on the (predetermined) duration of the insufflation method.

[0020] According to one embodiment, at least one of the following conditions is met: - the insufflation pressure is at least 80%, preferably at least 90%, of the insufflation target pressure for at least a predetermined duration; - the target pressure remains constant for at least a predetermined duration; the motor speed remains below a speed threshold value for at least a predetermined duration, the speed threshold value being selected taking into account the maximum possible motor speed in such a way that a drop in the supply pressure that occurs when switching the throttle device to the throttle position can be just compensated for by increasing the motor speed above the speed threshold value; The throttle device can be switched to the throttle position if

[0021] According to one embodiment, the insufflation method satisfies at least one of the following conditions: - the target pressure for delivery is numerically greater than the target pressure for exhaust that should be present at the patient connection during exhaust; the target air supply pressure exceeds a pressure threshold, which has been selected taking into account the maximum possible air supply pressure in such a way that a drop in the air supply pressure down to the pressure threshold, which occurs when switching the throttle device to the throttle position, can be barely compensated for by increasing the motor speed; - The function that produces the correct vibration of the air supply pressure is working. The method may further include preventing the throttle device from switching to the throttle position if

[0022] "Exhaust pressure" can be understood as a negative or minus pressure relative to the respective atmospheric pressure.

[0023] According to one embodiment, the throttle device can be switchable to at least one additional throttle position and can be designed to narrow the connecting channel differently when switching to the additional throttle position. In this case, the throttle device can pass through the additional throttle position when switching between the initial position and the throttle position. The connecting channel can be narrowed more when the throttle device is switched to the additional throttle position than when the throttle device is switched to the throttle position (or vice versa). In this way, the connecting channel can be narrowed continuously and / or in stages, for example, gradually and / or incrementally. This allows for better control of the narrowing of the connecting channel compared to embodiments with only one throttle position. This can avoid undesirable fluctuations in the delivery pressure when narrowing the connecting channel.

[0024] According to one embodiment, when switching to a throttle position, the throttle device can be moved first from the initial position to the additional throttle position at a first switching speed (or according to a predetermined first switching speed profile), and then from the additional throttle position to the throttle position at a second switching speed different from the first switching speed (or according to a predetermined second switching speed profile different from the first switching speed profile). In this case, the first switching speed can be (on average) significantly faster than the second switching speed (or vice versa). In other words, when switching to a throttle position, the throttle device can first be moved abruptly to the additional throttle position and then moved much more slowly to the throttle position. Such an embodiment using different switching speeds has proven particularly advantageous in experiments.

[0025] According to one embodiment, the control device, for example (immediately) after the insufflation method and / or (automatically) as a reaction to the end of the insufflation method, further performs the following exhaust method: switching the coupling device to the exhaust position, switching the throttle device to the initial position, receiving a pressure signal (if the coupling device is switched to the exhaust position), the pressure signal indicating the exhaust pressure present at the patient connection as detected pressure, determining an exhaust pressure deviation between the exhaust pressure and an exhaust target pressure, controlling the drive motor to reduce the exhaust pressure deviation, The switching of the coupling device can be performed simultaneously with the switching of the throttling device or with a (for example slight) time lag (for example before and / or after). The switching between the insufflation and exhaustion methods can be performed automatically and / or manually. Appropriately, the control unit can be designed to (automatically) alternate between the insufflation and exhaustion methods several times during the operation of the cough aid.

[0026] According to one embodiment, the coupling device can further be switchable to at least one intermediate position and can be designed to fluidly couple the pressure connection to both the inlet and the outlet in the intermediate position. In this case, the exhaust method can further include switching the coupling device from the exhaust position to the intermediate position to suppress undesirable fluctuations in the exhaust pressure. Undesirable pressure fluctuations can potentially occur due to the increased motor speed when switching to the exhaust position. To counteract this effect without significantly affecting pressure control, the coupling device can be switched to the intermediate position for a short time after reaching the exhaust position. To suppress undesirable pressure fluctuations, the coupling device can be switched several times between the exhaust position and the intermediate position and / or between several intermediate positions. For example, the coupling device can be designed to further vent the connecting channel in the intermediate position, thereby providing additional pressure compensation of the connecting channel with the surrounding environment.

[0027] According to one embodiment, the coupling device can be switched to and / or held in an intermediate position taking into account the time course of the exhaust pressure and / or the time course of the motor speed. In this way, a suitable switching time point for switching the coupling device between the exhaust position and the intermediate position can be determined depending on the current operating conditions of the cough aid device. Alternatively, the switching time point can be fixed and specified, for example depending on the (predetermined) duration of the exhaust method.

[0028] According to one embodiment, the amplitude of the pressure signal and / or the rotation speed signal indicative of the motor rotation speed can be compared with a predetermined tolerance range between which the amplitude varies over a number of consecutive time steps, and the coupling device can be switched between an exhaust position and an intermediate position depending on the deviation of the amplitude from at least one of the limits. The tolerance range can, for example, define a variation band on the order of plus / minus 20%, plus / minus 10%, plus / minus 5%, or plus / minus 1% of the desired average value of the amplitude. For example, if it is determined that the amplitude is within the tolerance range for at least a predetermined duration, the coupling device can be switched back to the exhaust position and held in the exhaust position until the end of the exhaust method.

[0029] Alternatively, the coupling device can be held in an intermediate position for a fixed, specified time frame.

[0030] According to one embodiment, the throttle device can be designed to be switchable between a first and a second oscillation position and to narrow the connecting channel when switching from the first oscillation position to the second oscillation position. In this case, the insufflation and / or exhaust method can further include a step of alternately switching the throttle device between the first and second oscillation positions to achieve a precise oscillation of the insufflation or exhaust pressure. This can further improve secretion discharge. The alternate switching can be performed after the (initial) switching of the throttle device to the initial position and / or taking into account the time course of the insufflation or exhaust pressure and / or the time course of the motor rotation speed. For example, the alternate switching can only be performed when it is recognized that the (measured) insufflation or exhaust pressure or the insufflation or exhaust target pressure is constant for at least a predetermined duration. In the above and below, the term "oscillation position" can be understood as a switching position designated for fixing the throttle device or that can be changed during operation of the cough aid device. The switching position can be changed, for example, according to the time transition of the pressure signal and / or the rotation speed signal indicating the motor rotation speed, and / or according to a predetermined vibration profile.

[0031] According to one embodiment, the first vibration position can be the initial position, or the first vibration position can be different from the initial position, for example, a position between the initial position and the throttle position.

[0032] According to one embodiment, the second vibration position can be the throttle position. Alternatively, the second vibration position can be different from the throttle position. In other words, the throttle device can be designed to narrow the connecting channel differently when switching to the second vibration position than when switching to the throttle position (and / or when switching to the aforementioned additional throttle position). Thus, the connecting channel can be narrowed more when the throttle device is switched to the second vibration position than when the throttle device is switched to the throttle position (or vice versa). The throttle device can pass through the throttle position (and possibly the aforementioned additional throttle position) when switching between the first vibration position and the second vibration position. This makes it possible, for example, to narrow or widen the connecting channel continuously and / or in stages, for example, gradually and / or incrementally, to provide the correct vibration.

[0033] If the air supply method is to produce precise oscillations in the air supply pressure, it is expedient if the throttle device is prevented from switching to a throttle position in order to further increase the motor speed.

[0034] According to one embodiment, the cough aid device may further comprise a flow sensor designed to detect a volumetric flow rate through the connecting channel and generate a flow rate signal indicative of the detected volumetric flow rate. In this case, the control device may be designed to further evaluate the flow rate signal in order to switch the coupling device and / or the throttle device and / or to control the drive motor. The flow rate sensor may, for example, be designed to detect a volumetric flow rate through a portion of the connecting channel located between the throttle device and the patient connection. This allows for more precise control of the operation of the cough aid device compared to embodiments that do not take the volumetric flow rate into account.

[0035] According to one embodiment, the ventilation method may further include receiving a flow signal, the flow signal indicating a volumetric flow rate evacuated as a detected volumetric flow rate, and evaluating the flow signal to recognize local maxima in the time course of the detected volumetric flow rate, whereby alternating switching may be performed to provide a precise oscillation in response to the recognition of a local maxima, e.g., a maximum expiratory flow rate.

[0036] According to one embodiment, the throttle device can include an adjusting member rotatably mounted about a rotation axis between an initial position and a throttle position, and an electric or electrically controllable actuator for rotating the adjusting member. The adjusting member can include a wall portion for reducing the flow cross-sectional area of ​​the connecting channel, and the wall portion can be designed to protrude further into the connecting channel in the throttle position than in the initial position.

[0037] According to one embodiment, the cough assist device may further comprise a ventilation channel that opens into the connecting channel and allows pressure compensation between the connecting channel and the surrounding environment. In this case, the throttle device may be designed to close the ventilation channel in the initial position and open the ventilation channel in the throttle position. This may be understood as meaning that the ventilation channel is narrowed more when the throttle device is switched to the initial position than when the throttle device is switched to the throttle position. For example, the ventilation channel may be completely narrowed, i.e., airtightly closed, in the initial position, or may be narrowed partially (e.g., by at least 5% and / or up to 95% relative to the throttle position), so that gas can continue to flow through the ventilation channel. This allows a slight internal leakage to occur when the throttle device is switched to the throttle position, which may have a favorable effect on the pressure profile.

[0038] Furthermore, the throttle device may be designed to close the ventilation channel in a first oscillation position and / or to open the ventilation channel in a second oscillation position.

[0039] Embodiments of the present invention will now be described with reference to the accompanying drawings, in which neither the description nor the drawings should be construed as limiting the scope of the invention. [Brief explanation of the drawings]

[0040] [Figure 1] 1 shows a cough aid device according to an embodiment of the present invention with the coupling device in the insufflation position and the throttle device in the initial position. FIG. [Figure 2] 2 shows the cough aid device of FIG. 1 with the throttle device in a first throttle position. [Figure 3] 2 shows the cough aid device of FIG. 1 with the throttle device in a second throttle position. [Figure 4] 2 shows the cough aid device of FIG. 1 with the coupling device in the exhaust position. [Figure 5] 5 shows the cough aid device of FIG. 4 with the coupling device in an intermediate position. [Figure 6] 5 shows the cough aid device of FIG. 4 with the throttle device in a vibrating position. [Figure 7] FIG. 10 is a diagram showing the time progression of pressure and volume flow rate during operation of a cough assist device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] The figures are purely schematic and not to scale. Where the same reference signs are used in different figures, these signify the same or identical functional features.

[0042] 1 shows a cough assistance device 1 for assisting a patient's cough. The cough assistance device 1 includes an inlet 5, an outlet 7, a drive motor 9, and a blower 3 having a rotor 11 coupled to the drive motor 9 for transferring gas from the inlet 5 to the outlet 7 in accordance with the motor rotation speed of the drive motor 7. The direction of gas flow is indicated by dashed arrows.

[0043] Furthermore, the cough aid device 1 comprises a pressure connection 13 and a patient connection 17 for connecting a patient interface, e.g. a mask, a mouthpiece, an endotracheal cannula or a tracheostomy cannula, which is fluidly connected to the pressure connection 13 via a connection channel 15. Both connections 13, 15 can be designed, for example, as connections for a pneumatic unit 19. The pneumatic unit 19 can be designed, for example, as a valve housing or a valve block.

[0044] Furthermore, the cough aid device 1 comprises a coupling device 21 , a throttle device 23 , a pressure sensor 25 and a control device 27 for controlling the operation of the cough aid device 1 .

[0045] The coupling device 21, here in the form of a butterfly valve, is switchable between an air supply position and an exhaust position and is designed to fluidly couple the pressure connection 13 to the outlet 7 in the air supply position (see Figures 1 to 3) and to the intake 5 in the exhaust position (see Figures 4 and 6).

[0046] The throttle device 23 is switchable between an initial position (see Figures 1 and 4) and a throttle position (see Figure 3), and is designed to precisely narrow the connecting channel 15 when switched from the initial position to the throttle position.

[0047] Pressure sensor 25 is designed to sense the pressure present at patient connection 17 and generate a pressure signal 29 indicative of the sensed pressure.

[0048] The control device 27 is designed to perform the following delivery method: switching the coupling device 21 to the delivery position; receiving a pressure signal 29, which indicates the delivery pressure present at the patient connection 17 as the detected pressure; determining the delivery pressure deviation between the delivery pressure and a delivery target pressure, e.g., set manually; controlling the drive motor 9 to reduce the delivery pressure deviation; when controlling the drive motor 9, switching the throttle device 23 to the throttle position and holding the throttle device 23 in the throttle position in order to further increase the motor speed.

[0049] For example, the throttle device 23 can be held in the throttle position until the coupling device 21 is switched to the exhaust position to initiate exhaust. It is also conceivable that the throttle device 23 is held in the throttle position for a short time beyond the time of switching to the exhaust position. Alternatively, the throttle device 23 can be switched to the initial position already just before the time of switching to the exhaust position.

[0050] This allows a significant increase in PCF without requiring a more powerful blower or a faster changeover from the blowing position to the exhaust position. Throttling has the effect of further increasing the flow resistance that the blower faces during the blowing, especially towards the end of the blowing. Pressure control results in a corresponding increase in motor speed. This makes it possible to provide a correspondingly increased volumetric flow rate in the subsequent exhaust.

[0051] The coupling device 21 and the throttle device 23 may each comprise an electric or electrically controllable actuator 31 for switching between their respective switching positions. Such actuator 31 may be, for example, an electric motor, an electromagnet, a piezoelectric element, or a combination of at least two of these examples.

[0052] Furthermore, the control device 27 can be designed to perform the following exhaust method following the insufflation method: switching the coupling device 21 to the exhaust position, switching the throttle device 23 back to its initial position, for example at the same time as switching the coupling device 21 to the exhaust position, receiving a pressure signal 29 indicating the exhaust pressure present in the patient connection 17 as the detected pressure, determining the exhaust pressure deviation between the exhaust pressure and an exhaust target pressure, for example also set manually, and controlling the drive motor 9 to reduce the exhaust pressure deviation.

[0053] The switching between the insufflation and exhaust modes can be done manually and / or automatically.

[0054] For example, the control device 27 can be designed to switch the cough aid device 1 to a pause position (see section "P" in Figure 7) between two cough cycles, and the cough aid device 1 is designed so that in the pause position the respective atmospheric pressure is present at the patient connection part 17.

[0055] In the air supply method, it is expedient if the throttle device 23 is switched to and / or held in the throttle position taking into account the time course 33 of the supply pressure (see FIG. 7) and / or the time course of the motor speed. This makes it possible to control the throttle device 23 depending on the current operating conditions of the cough aid device 1. However, it is also possible to switch the throttle device 23 at fixedly specified switching times. In FIG. 7, possible throttle throttling time periods 34 during which the throttle device 23 is held in the throttle position are exemplarily shown.

[0056] The control device 27 can be designed to switch the throttle device 23 to a throttle position depending on whether certain switching conditions are met.

[0057] The switching conditions may be, for example, the following requirements: the target supply pressure is at most numerically the same as the target exhaust pressure (if this is not the case, the drive motor 9 will in any case operate at a higher motor speed in the supply mode than in the exhaust mode), the target air pressure is at most equal to a predetermined pressure threshold, which is selected taking into account the maximum possible air pressure, so that a drop in the air pressure down to the threshold pressure, which occurs when the throttle device 23 is switched to the throttle position, can be barely compensated for by increasing the motor speed (if the target air pressure exceeds the pressure threshold, there may not be a sufficient speed reserve), - If there is a function for providing a precise oscillation of the air supply pressure, it is deactivated; may include:

[0058] Depending on the embodiment of the cough aid device 1, in particular the blower 3, the pressure threshold can be, for example, between 40 hPa and 70 hPa, in particular between 50 hPa and 60 hPa.

[0059] If at least one of the necessary conditions is not met, the control device 27 prohibits the throttle device 23 from switching to the throttle position during air delivery.

[0060] Furthermore, the switching condition may be, for example, the following sufficient condition: - the (measured) insufflation pressure is at least 80%, preferably at least 90%, of the insufflation target pressure for at least a predetermined duration; - the insufflation target pressure remains constant for at least a predetermined duration (i.e., the insufflation target pressure reaches a predetermined plateau phase); The motor speed may be below a predetermined threshold speed for at least a predetermined duration, the threshold speed being selected taking into account the maximum possible motor speed so that the drop in air pressure that occurs when the throttle device 23 is switched to the throttle position can be just barely compensated for by increasing the motor speed above the threshold speed.

[0061] If each of the sufficient conditions is true, the control device 27 switches the throttle device 23 to the throttle position during delivery.

[0062] Depending on the embodiment of the cough aid device 1, in particular the blower 3, the rotational speed threshold can be, for example, 20,000 to 60,000, in particular 35,000 to 45,000, preferably 42,000 rpm.

[0063] The predetermined duration can be, for example, 0.1 s to 1 s, preferably 0.4 s to 0.7 s, in particular 0.5 s.

[0064] The check on whether the above conditions are met can be performed at a number of successive time steps, for example 50 to 200 times per second, in particular 90 to 110 times per second.

[0065] As shown in FIG. 2, the throttle device 23 can be switchable to at least one additional throttle position located between the initial position and the throttle position, and can be designed so that when switching to the additional throttle position, the connecting channel 15 is narrowed differently, for example, more than when switching to the throttle position. In that case, the air delivery method begins from the initial position. If the above conditions are met, for example, the throttle device 23 is first abruptly switched to the additional throttle position, with the flow resistance against the blower 3 being significantly increased compared to the initial position. The throttle device 23 is then moved from the additional throttle position to the throttle position at a reduced adjustment speed. For example, the throttle device 23 can be designed so that the ventilation channel 35 opening into the connecting channel 15 is airtightly closed in the initial position (and possibly in the additional throttle position) and partially opened in the throttle position, so that in the throttle position an additional pressure compensation of the connecting channel 15 with the surrounding environment is achieved. This can have a favorable effect on the pressure profile.

[0066] Furthermore, the throttle device 23 can be switchable between a first and a second oscillation position and can be designed to narrow the connecting channel 15 when switching from the first to the second oscillation position. In this case, the throttle device 23 can be alternately switched between the first and second oscillation positions several times in the air supply and / or exhaust process to provide a precise oscillation of the air supply pressure or the exhaust pressure.

[0067] In this example, the first oscillation position corresponds to the initial position, whereas the second oscillation position (see FIG. 6) is a position different from the throttle position or positions where the throttle device 23 fully opens the ventilation channel 35 different from the throttle position or positions.

[0068] In addition to the pressure signal 29, the control device 27 can receive a flow signal 37 from a flow sensor 39 for detecting the volumetric flow through the part of the connecting channel 15 located between the throttle device 23 and the patient connection 17. In this case, the alternating switching between the first and second oscillation positions in the exhaust method can only take place when it is recognized, for example, on the basis of the flow signal 37 that the exhausted volumetric flow has reached a local maximum, also called PCF. Figure 7 exemplarily shows the time course 41 of the volumetric flow during operation of the cough aid device 1.

[0069] The control device 27 can also be designed to evaluate the flow signal 37 for controlling the drive motor 9 and / or the coupling device 21 .

[0070] In order to suppress excessive pressure peaks at the beginning of the exhaust process, the coupling device 21 can additionally be designed to be switchable to at least one intermediate position (see FIG. 5) and to fluidly couple the pressure connection 13 to both the inlet 5 and the outlet 7 in the intermediate position. In FIG. 7, possible suppression time frames 42 are exemplarily shown, during which the coupling device 21 is held in an intermediate position or alternately switched between the exhaust position and the intermediate position (and / or between several intermediate positions).

[0071] For example, the control device 27 can be designed to switch the coupling device 21 between the exhaust position and an intermediate position (and / or between several intermediate positions) taking into account the time course of the exhaust pressure 33 and / or the time course of the motor speed. For this purpose, for example, the amplitude of the pressure signal 29 and / or the speed signal indicative of the motor speed can be compared with a predetermined tolerance range within which the amplitude may vary in several consecutive time steps. Thus, the coupling device 21 can be switched between the exhaust position and an intermediate position (and / or between several intermediate positions) depending on the deviation of the amplitude from at least one of the limits.

[0072] The throttle device 23 may, for example, comprise an adjusting member 45 rotatable about a rotation axis 43 between an initial position and an end position by the respective actuator 31, and having a wall 47 for reducing the flow cross-sectional area of ​​the connecting channel 15. In this example, the end position is the second oscillation position, and the adjusting member 45 passes through a throttle position (or several throttle positions) when rotating between the initial position (here coinciding with the first oscillation position) and the end position. The throttle device 23 may then be designed such that the wall 47 protrudes further into the connecting channel 15 in the end position and / or at each throttle position than in the initial position.

[0073] The cough assist device 1 can be designed as a stand-alone device or as a component of a ventilator 49 for invasive and / or non-invasive ventilation of a patient.

[0074] Finally, it is noted that the words "having", "comprising", "including", "with" and the like do not exclude other elements or steps, and that the indefinite article "a" or "an" does not exclude a plurality.

[0075] Furthermore, it is noted that features or steps described with reference to one of the above embodiments may also be used in combination with features or steps described with reference to other of the above embodiments.

[0076] Any reference signs in the claims should not be construed as limiting the scope of the subject matter defined by the claims. [Explanation of symbols]

[0077] 1. Cough assist device 3. Blower 5 Intake port 7 Air outlet 9 Drive motor 11 rotor 13 Pressure Connection 15 connection channels 17 Patient Connection 19 Pneumatic unit 21 Coupling device 23 Throttle device 25 Pressure Sensor 27 Control Device 29 Pressure Signal 31 Actuator 33 Time transition of pressure present at the patient connection 34 Throttle Time Frame 35 ventilation channels 37 Flow signal 39 Flow Sensor 41 Time course of volume flow through the connecting channel 42 Suppression Time Frame 43 Rotation axis 45 Adjustment member 47 Wall 49 Respirator p pressure t time E Exhaust I Air Supply P Pause PCF peak expiratory flow Q Volumetric flow rate

Claims

1. A cough assistance device (1) for assisting a patient's cough, the cough assistance device (1) comprising: a blower (3) having an inlet (5), an outlet (7), a drive motor (9), and a rotor (11) coupled to the drive motor (9) for transferring gas from the inlet (5) to the outlet (7) in accordance with the motor rotation speed of the drive motor (9); a pressure connection (13); a patient connection (17) for connecting a patient interface; a connection channel (15) fluidly connecting said pressure connection (13) to said patient connection (17); a coupling device (21) switchable between an air supply position and an exhaust position and designed to fluidly couple the pressure connection (13) to the outlet (7) in the air supply position and to fluidly couple the pressure connection (13) to the inlet (5) in the exhaust position; a throttle device (23) switchable between an initial position and a throttle position and designed to narrow said connecting channel (15) when switched to said throttle position; a pressure sensor (25) designed to detect a pressure (p) present at said patient connection (17) and to generate a pressure signal (29) indicative of said detected pressure (p); A control device (27) for controlling the operation of the cough assistance device (1), which is configured to perform the following air supply methods: Switching the coupling device (21) to the air delivery position; receiving the pressure signal (29), the pressure signal (29) indicating the insufflation pressure (p) present at the patient connection (17) as the detected pressure (p); determining a deviation between the air delivery pressure (p) and a target air delivery pressure; controlling the drive motor (9) to reduce the air supply pressure deviation; switching the throttle device (23) to the throttle position to further increase the motor rotation speed, and holding the throttle device (23) at the throttle position; a control device (27) designed to execute the A cough assistance device (1) comprising:

2. The throttle device (23) is held in the throttle position at least until the coupling device (21) is switched to the exhaust position; and / or the throttle device (23) is switched to the throttle position and / or maintained at the throttle position in consideration of a time transition (33) of the air supply pressure (p) and / or a time transition of the motor rotation speed. A coughing aid device (1) according to claim 1.

3. The throttle device (23) satisfies at least one of the following conditions: the insufflation pressure (p) is at least 80%, preferably at least 90%, of the insufflation target pressure for at least a predetermined duration; the target pressure remains constant for at least a predetermined duration; the motor speed remains below a speed threshold for at least a predetermined duration, the speed threshold being selected taking into account the maximum possible motor speed so that a drop in the air supply pressure (p) that occurs when switching the throttle device (23) to the throttle position can be just compensated for by increasing the motor speed above the speed threshold; and switching to said throttle position when A coughing aid device (1) according to any one of the preceding claims.

4. The gas supply method includes: At least one of the following conditions: the target pressure is numerically greater than the target pressure to be present at the patient connection (17) during exhaust; the target air supply pressure exceeds a pressure threshold value, and the pressure threshold value is selected taking into account the maximum possible air supply pressure so that a drop in the air supply pressure (p) to the pressure threshold value, which occurs when the throttle device (23) is switched to the throttle position, can be barely compensated for by increasing the motor rotation speed; The function of causing the precise oscillation of the air supply pressure (p) is operating. and further comprising preventing the throttle device (23) from being switched to the throttle position when A coughing aid device (1) according to any one of the preceding claims.

5. the throttle device (23) is switchable to at least one additional throttle position and is designed to narrow the connecting channel (15) differently when switching to the additional throttle position than when switching to the throttle position, and the throttle device (23) passes through the additional throttle position when switching between the initial position and the throttle position; A coughing aid device (1) according to any one of the preceding claims.

6. When switching to the throttle position, the throttle device (23) is first moved from the initial position to the additional throttle position at a first switching speed, and then moved from the additional throttle position to the throttle position at a second switching speed. A coughing aid device (1) according to claim 5.

7. The control device (27) further includes the following exhaust method: Switching the coupling device (21) to the exhaust position; Switching the throttle device (23) to the initial position; receiving the pressure signal (29), the pressure signal (29) indicating the exhaust pressure (p) present at the patient connection (17) as the detected pressure (p); determining an exhaust pressure deviation between the exhaust pressure (p) and an exhaust target pressure; controlling the drive motor (9) to reduce the exhaust pressure deviation; It is designed to perform A coughing aid device (1) according to any one of the preceding claims.

8. the coupling device (21) is further designed to be switchable to at least one intermediate position and to fluidly couple the pressure connection (13) to both the inlet (5) and the outlet (7) in the intermediate position; The exhaust method further includes: switching the coupling device (21) from the exhaust position to the intermediate position to suppress undesired fluctuations in the exhaust pressure (p). A coughing aid device (1) according to claim 7.

9. the coupling device (21) is switched to and / or held at the intermediate position taking into account the time course (33) of the exhaust pressure (p) and / or the time course of the motor rotation speed. A coughing aid device (1) according to claim 8.

10. the throttle device (23) is further switchable between a first vibration position and a second vibration position and is designed to narrow the connecting channel (15) when switching from the first vibration position to the second vibration position; The exhaust method further includes: and alternating the throttle device (23) between the first and second oscillation positions to provide a precise oscillation of the exhaust pressure (p). A coughing aid device (1) according to any one of claims 7 to 9.

11. a flow sensor (39) designed to detect a volumetric flow rate (Q) through said connecting channel (15) and to generate a flow signal (37) indicative of said detected volumetric flow rate (Q); the control device (27) is designed to further evaluate the flow rate signal (37) for switching the coupling device (21) and / or the throttle device (23) and / or for controlling the drive motor (9); A coughing aid device (1) according to any one of the preceding claims.

12. The pumping method further includes receiving the flow rate signal (37), the flow rate signal (37) indicating the pumped volumetric flow rate (Q) as the detected volumetric flow rate (Q); The alternating switching to provide the correct oscillation occurs only when the pumped volume flow rate (Q) reaches a local maximum value (PCF). A coughing aid device (1) according to claim 11, which relies on claim 10.

13. The throttle device (23) comprises an adjusting member (45) rotatably mounted about a rotation axis (43) between the initial position and the throttle position, and an electric actuator (31) for rotating the adjusting member (45), the adjusting member (45) having a wall portion (47) for reducing a flow cross-sectional area of ​​the connecting channel (15), and the wall portion (47) is designed to protrude further into the connecting channel (15) at the throttle position than at the initial position. A coughing aid device (1) according to any one of the preceding claims.

14. a ventilation channel (35) opening into said connecting channel (15) for enabling pressure compensation of said connecting channel (15) with the surrounding environment; the throttle device (23) is designed to close the ventilation channel (35) in the initial position and to open it in the throttle position; A coughing aid device (1) according to any one of the preceding claims.

15. A ventilator (49) for invasive and / or non-invasive ventilation of a patient, comprising a cough assist device (1) according to any one of the preceding claims.

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