Equipment for non-invasive assisted ventilation of living beings

Abstract

The present invention relates to a device (1) for assisted ventilation of a living being (3), the device comprising a sensor device, a programmable control unit (10) and an air delivery unit (6) which can be controlled by the control unit (10). The sensor device comprises a pressure sensor (9) and an air flow sensor (11), the pressure sensor and the air flow sensor being configured to detect respiratory pressure values ​​and respiratory air flow values ​​of the living being (3) in succession in time. The programmable control unit (10) is configured to evaluate a respiratory pressure change curve and a respiratory air flow change curve formed by the respiratory pressure values ​​and respiratory air flow values ​​detected in succession in time by the sensor device. In order to provide a breathing that is particularly comfortable for the living being (3) and is individually adapted to the instantaneous needs of the living being (3), it is proposed that the programmable control unit (10) is configured to identify frustrated breathing movements of the living being (3) and their causes based on characteristic features of the respiratory pressure change curve and / or the respiratory air flow change curve. The invention also relates to a computer program having program code means, which is designed to carry out a method for assisted ventilation of a living being (3) using a ventilator (1) when the computer program is executed on a computing unit of the ventilator (1).

Description

Technical Field

[0001] The invention relates to a device for assisted ventilation of a living being. The invention also relates to a computer program having program code means. Background Art

[0002] In general, the present invention relates to the field of assisted ventilation of patients with respiratory problems. In this case, assisted ventilation refers to the breathing of an organism that performs breathing movements autonomously during breathing. For example, so-called assisted and partially controlled breathing is included, in which the breathing effort of the organism is recognized by the device, and according to the natural breathing of the organism, the inhalation ("inspiration") or exhalation ("exspiration") of the organism is promoted by a negative pressure or overpressure induced by the device in the respiratory tract of the organism relative to the pressure currently existing. Inhalation is a breathing phase with an air flow mainly inwards towards the organism, and exhalation is a breathing phase with an air flow mainly away from the organism. In addition, controlled breathing is known in medicine, which is distinguished from assisted ventilation in terms of whether the patient who breathes in a controlled manner does not perform autonomous breathing movements or whether the patient is forced to breathe, and the patient must adapt to the controlled breathing through his autonomous breathing efforts. In controlled breathing, the ventilation rate and thus the inhalation and exhalation phases are preset by the device, and in the case of assisted breathing, the ventilation rate and thus the inhalation and exhalation phases are automatically adapted by the device to the spontaneous breathing of the living being. Partially controlled breathing is based on assisted breathing, but the minimum ventilation rate ("safety rate" or "assisted rate") is preset by the device. Examples of devices for assisted ventilation are BiPAP-S, Bilevel-S or PSV devices in the case of assisted breathing, PCV or BiPAP-T devices in the case of controlled breathing, and BiPAP-ST or aPCV devices in the case of partially controlled breathing.

[0003] Examples of organisms requiring assisted ventilation include COPD patients, in particular patients with hypercapnic respiratory failure. In these patients, structural changes in the lungs occur as a result of the various diseases, which require the respiratory muscles to work harder in order to ensure adequate gas exchange. As the disease progresses, the respiratory muscles become increasingly fatigued, thus causing a sensation of shortness of breath with very little effort when breathing. In the cases presented, the respiratory muscles and the respiratory drive, especially even during sleep at night, are no longer able to fully compensate for the structural changes in the lungs caused by the increased depth of breathing and increased ventilation frequency and cause hypoventilation.

[0004] EP 2542286A2 discloses a ventilation device having a controllable air delivery unit or a valve control unit with a pressure regulating valve, wherein the ventilation device has an air mass meter, a pressure sensor and a programmable control unit. In order to avoid undesired overinflation of the lungs of a ventilated organism, when controlling the air delivery unit or the valve control unit, an early reduced pressure profile of the organism in the inhalation phase and a dynamically controlled counterpressure in the exhalation phase are set.

[0005] WO 2006 / 079152A1 discloses a method and a system for identifying inefficient breathing movements of a ventilating organism. To this end, disturbances in the exhaled breathing air flow of the organism are monitored. Summary of the invention

[0006] The object of the present invention is to specify an improved device for assisted ventilation, by which ventilation is provided which is particularly comfortable for the living being and is individually adapted to the temporary needs of the living being.

[0007] This object is achieved by a device according to an embodiment and a computer program according to an embodiment. Advantageous embodiments are described in the following exemplary embodiments.

[0008] The device is used for assisted ventilation of a living being, such as a human being. For example, assisted ventilation may be necessary due to respiratory or lung diseases of the living being, so the living being is also referred to as a patient in this application. The device has a controllable air delivery unit, which has, for example, a fan, a pump, a controllable turbine or an air compression device, such as a piston compressor. In order to control the amount of air output, the air delivery unit can additionally have a pressure control valve or a valve device. A valve control device can also be provided to replace the air delivery unit. The valve control device can be connected as an additional device between a conventional ventilation device and the living being to be breathed.

[0009] The air delivery unit can for example selectively, in particular automatically, generate a negative pressure or an overpressure that can be set steplessly, for example by adjusting the rotation direction and speed of the fan. In this way, the corresponding currently required breathing assistance can be provided to the organism.

[0010] It is common in the prior art that conventional devices for inspiration increase the respiratory pressure provided by the device ("IPAP" = Inspiratory Positive Airway Pressure, the respiratory pressure during inspiration) and reduce the respiratory pressure for exhalation ("EPAP" = Expiratory Positive Airway Pressure, the respiratory pressure during exhalation). IPAP and EPAP are usually determined by the therapist and set on the device. In addition to IPAP and EPAP, the ventilation frequency, the IPAP time (the duration of the inspiratory pressure in the inspiratory phase), the time ratio of IPAP / EPAP and the preset sensitivity of the inspiratory and expiratory triggers, which will be explained below, are usually determined. If a sufficient tidal volume and / or a sufficient minute volume is achieved, the ventilation is generally considered to be efficient. The sufficiency is determined in particular based on empirical values, basic ventilation indicators, diseases and blood gas analysis.

[0011] The switching of the device from EPAP to IPAP marks the end of the exhalation mode and the beginning of the inhalation mode, which lasts until the device switches from IPAP to EPAP. The switching of the device from IPAP to EPAP marks the end of the inhalation mode and the beginning of the exhalation mode, which lasts until the device switches from EPAP to IPAP.

[0012] The device has a sensor device with a pressure sensor and an air flow sensor. The pressure sensor can be, for example, a differential pressure sensor, and the air flow sensor can be, for example, a pneumotachometer. The two sensors can be arranged in a common housing or can be arranged spatially separately from each other. In order to detect the respiratory air pressure value and the respiratory air flow value of the biological being, the sensor is, for example, arranged in or on the breathing mask, or arranged in or on the connecting hose between the ventilation device and the breathing mask, or arranged in the valve control device of the device. In general, in conjunction with the present application, the word "one" should not be understood as a numeral, but should be understood as an indefinite article with the literal meaning of "at least one". Therefore, for example, multiple pressure or air flow sensors can also be arranged. The pressure sensor and the air flow sensor are set up to detect the respiratory air pressure value and the respiratory air flow value of the biological being in succession in time, so that the sensor is suitable for continuously measuring the mentioned values.

[0013] The detected respiratory pressure value and respiratory airflow value are transmitted to the programmable control unit of the device, for example, continuously or quasi-continuously and evaluated by the control unit. For this purpose, the programmable control unit has a suitable computing unit and a storage device and / or suitable software that may be required, so as to evaluate a plurality of respiratory pressure values ​​and / or respiratory airflow values ​​that are sequential in time, for example, separately or in relation to each other. Since the respiratory pressure value and the respiratory airflow value are sequential in time, they are also referred to as respiratory pressure change curves and respiratory airflow change curves in the application document, so as to distinguish them from the evaluation of each absolute value that is independent of time, for example, in the process of a single threshold monitoring. The respiratory pressure change curve and the respiratory airflow change curve can be shown in practice, for example, as a function curve or a curve segment, for illustration, and thus depict the relative or absolute time change curve of the pressure value or the airflow value. When evaluating, on the one hand, the absolute respiratory pressure value and the respiratory airflow value at different time points, as well as the relative time change of the corresponding values ​​can be considered. In particular, it is also possible to perform a continuous evaluation of the respiratory pressure change curve and the respiratory airflow change curve in relation to each other.

[0014] According to the present invention, a programmable control unit is set up to identify ventilation-related frustrated breathing movements of a living being based on the characteristic features of a respiratory pressure change curve and / or a respiratory airflow change curve. Frustrated breathing movements under ventilation conditions are understood as breathing efforts of a living being that do not cause the amount of air received or output as sought with such breathing efforts, such as not being fully recognized as breathing efforts by a device used for assisted ventilation and therefore not causing the device to switch from an inhalation mode to an exhalation mode or vice versa from an exhalation mode to an inhalation mode. Such frustrated breathing movements can make the patient feel uncomfortable and may lead to perceived shortness of breath or shallow breathing. However, frustrated breathing movements may also be only ineffective, especially during sleep, and only cause an increase in respiratory work, which can resist the original goal of breathing, because breathing, for example, has the following purpose: to minimize the patient's respiratory work. Frustrated breathing movements may occur during the inhalation phase and / or exhalation phase of the living being, or at a time point at which there is an outwardly oriented or inwardly oriented air flow, or at a time point at which the pressure applied by the device is at an IPAP level or an EPAP level. Although obstructive sleep-related dysregulation of breathing may also result in frustrated respiratory movements, it is not primarily present in the context of respiratory conditions and is therefore fundamentally distinguishable.

[0015] In order to identify frustrated breathing movements associated with ventilation equipment, hereinafter referred to as frustrated breathing movements, a programmable control unit analyzes a respiratory pressure change curve and / or a respiratory airflow change curve formed by respiratory pressure values ​​and respiratory airflows detected in succession in time by a sensor device. It has been recognized that frustrated breathing movements can be identified based on the characteristic features in the change curve of the detected sensor values. Accordingly, in the current case, frustrated breathing movements are identified only based on the respiratory pressure change curve and / or the respiratory airflow change curve, so that the presence of frustrated breathing movements can be inferred using one or two sensors that are usually used for other measurement purposes in such equipment. Therefore, in particular, no additional sensors are required to identify frustrated breathing movements, such as measurement probes guided into the respiratory organs, as are commonly seen in esophageal probes, occlusion measurements, or multi-image analysis or polysomnography analysis for examining and monitoring related patients. Therefore, the present invention is based on non-invasive identification of frustrated breathing movements. At the same time, the device according to the present invention has a simple structure and a simple working method.

[0016] Surprisingly, despite the fact that the evaluation is limited to one or two physical quantities, it is possible to draw reliable conclusions about the occurrence of frustrated breathing movements, because in this case the characteristic features that appear in the respiratory pressure curve and / or the respiratory air flow curve are clear, verifiable and reproducible. In this case, the following effect is particularly utilized: the time value curve has a significantly higher information density than the instantaneous values ​​considered separately. In particular, the time value curve can also be evaluated over a longer period of time using suitable storage or transmission devices, and for example, a long-term observation of any accompanying conditions or triggering of frustrated breathing movements is possible.

[0017] Therefore, the observation of the respiratory pressure values ​​and the respiratory airflow values ​​over time can provide valuable information about the instantaneous or long-term observed breathing-related state of the living being. In addition, due to the precise analysis of the breathing of the living being, it is possible within the scope of the present invention to set customized countermeasures for frustrated breathing movements identified according to characteristic features. In particular, frustrated breathing movements that are manifested differently or triggered differently can be optionally distinguished according to different characteristic features, as will be explained below. Through this distinction, it becomes possible to adapt the corresponding corresponding measures to the patient's breathing and ventilation conditions individually.

[0018] Characteristic features of frustrated respiratory movement can be the maximum value, minimum value, inflection point, saddle point, amplitude, integral and / or derivative in a predetermined time point and / or time period of the respiratory pressure change curve and / or the respiratory airflow change curve. In this case, each local or regional feature can be considered separately or related to other features and is called as characteristic. Therefore, for example, in the exhalation phase of the respiratory pressure change curve, the local minimum value can be used as a characteristic feature of frustrated respiratory movement together with the local maximum value following it in a preset time period. For example, in the respiratory airflow change curve, two consecutive respiratory airflow increases in the preset time period in the exhalation phase can be used as a characteristic feature of frustrated respiratory movement. The oscillation that occurs in the respiratory airflow and / or respiratory pressure change curve in a predefined time period can also be used as a characteristic feature of one or more consecutive frustrated respiratory movements. In this case, the following examples are respectively involved, which are not exhaustively regarded as an enumeration of characteristic features, especially because the accurate identification and analysis of frustrated respiratory movement based on the respiratory airflow and respiratory pressure change curve depending on the patient's breathing and ventilation state may have high complexity.

[0019] According to an advantageous embodiment, the characteristic feature is a characteristic deviation from a preset reference respiratory pressure change curve and / or a reference respiratory air flow change curve. In this design, for example, in a programmable control unit, the respiratory pressure change curve and / or the respiratory air flow change curve detected by the sensor device is compared with the reference change curve, for example, it is superimposed in a calculation or graphical manner, and the shape, intensity and appearance of possible deviations between the detected change curve and the reference change curve are determined. For example, the deviation of the currently detected respiratory pressure change curve and / or the respiratory air flow change curve from the reference change curve at a specific time point, especially during the exhalation phase, which is formed as a respiratory pressure or respiratory air flow peak, can be used as a characteristic deviation. The reference respiratory pressure change curve and / or the reference respiratory air flow change curve can be preset, for example, as a reference change curve that is pre-stored and stored in the programmable control unit. It is also possible that the device "learns" such a reference respiratory pressure change curve and / or a reference respiratory air flow change curve based on a previous evaluation and even stores it in the programmable control unit in order to better take into account the individual breathing conditions of the patient. Such a learning process can be triggered and carried out, for example, under medical supervision in order to monitor an at least approximately ideal regular ventilation process and not to make the identification of frustrated breathing movements difficult due to the frustrated breathing movements that have already occurred in this case when the profile is later compared with a reference profile.

[0020] According to an advantageous embodiment, the programmable control unit has a memory unit for storing preset reference respiratory pressure change curves and / or reference respiratory airflow change curves and / or reference features for characteristic features of frustrated respiratory movements, in order to simplify the internal evaluation of deviations and / or features by comparison.

[0021] According to an advantageous embodiment, the storage unit has different disease-specific reference respiratory pressure change curves and / or reference respiratory airflow change curves and / or different disease-specific reference features for the characteristic features of frustrated respiratory movements. In this way, the characteristics of the characteristic-specific disease of frustrated respiratory movements can be considered more accurately and individually. The reference respiratory pressure change curve and / or the reference respiratory airflow change curve and / or the reference features can be stored in a storage unit of a programmable control unit in a table form, for example, so that the control unit can select or limit the relevant features or change curves by row or by column. According to an advantageous embodiment, the device has a setting possibility for selecting a specific disease or a manifestation-specific disease by a person, such as a therapist or a patient. The setting possibility can be, for example, a data interface or a user interface for a storage medium. Alternatively or additionally, the programmable control unit is set up to automatically identify the existing disease, for example, based on the characteristics of the corresponding disease characterized by the respiratory pressure change curve and / or the respiratory airflow change curve.

[0022] According to an advantageous embodiment, the programmable control unit is configured to identify frustrated breathing movements of the living being based on phase differences occurring between the living being's actual ventilation phase and the ventilation phase performed by the device. In this case, the device automatically or autonomously identifies that the switching of the device from the exhalation mode to the inhalation mode or vice versa is performed incorrectly, for example too early or too late or not at all. In order to identify phase differences, the above-mentioned characteristic features of the respiratory pressure change curve and / or the respiratory air flow change curve can be used in particular, in that the characteristic deviation from a preset reference respiratory pressure change curve and / or a reference respiratory air flow change curve is, for example, identified by the programmable control unit. In an advantageous embodiment, the programmable control unit can also determine the extent of the phase difference that occurs, for example, determining the time offset between the expected characteristic feature and the actually determined characteristic feature. It is thus possible to determine to what extent the inhalation mode or exhalation mode of the device lags behind or leads the actual inhalation or exhalation of the living being or is completely separated from it.

[0023] According to an advantageous embodiment, the programmable control unit is configured to differentiate between frustrated breathing movements that occur due to the biological endogenous PEEP and frustrated breathing movements that occur due to insufficient triggering, which will be described below, based on characteristic features of the respiratory pressure change curve and / or the respiratory airflow change curve. In this case, the device can thus identify and differentiate between two essential causes of frustrated breathing movements that often occur in practice.

[0024] The abbreviation PEEP stands for the technical term "positive end-expiratory pressure" and thus denotes the pressure that is present in the respiratory tract of a living being at the end of the exhalation phase. In the case of an incomplete exhalation, which occurs, for example, due to a pressure regulated by an auxiliary ventilation device or a counterpressure that is induced dynamically, in particular during the exhalation phase, this residual pressure in the respiratory organs increases at the end of exhalation and is then referred to as intrinsic PEEP or auto-PEEP. The intrinsic PEEP can behave very differently regionally in the lung of a living being. In particular, an incomplete exhalation can also occur if the patient inhales but exhalation has not yet ended.

[0025] In particular, in a plurality of breathing cycles, the increased intrinsic PEEP leads to an increased respiratory load and forms a threshold value for the patient, which must be overcome at each inhalation in addition to the load positively correlated with the depth of breathing. In addition, the increased intrinsic PEEP leads to an increased and also differently formed excessive distension in the lungs of the organism, because the residual pressure can no longer fully escape into the environment. Therefore, the intrinsic PEEP is not only uncomfortable for the patient, but also dangerous. A feeling of shortness of breath may occur, but it may also have a negative impact on the cardiovascular condition. In addition, oscillating air may be generated in the case of ventilation. Ventilation may also become ineffective, which leads to additional loading of the lung structure. Therefore, during the assisted ventilation of the organism, the establishment of the intrinsic PEEP should be avoided as much as possible or at least reduced. In this case, it should be noted that the intrinsic PEEP can change continuously, for example, related to the current disease, infection status, increased mucus secretion (Verschleimung), respiratory rate or patient psychological condition.

[0026] In the case of assisted ventilation, intrinsic PEEP may lead to frustrated breathing movements of the patient, in which the residual pressure in the airway changes due to ineffective breathing efforts. Such frustrated breathing movements can be read based on the features characterizing intrinsic PEEP in the respiratory pressure change curve and / or the respiratory airflow change curve, so that intrinsic PEEP as the cause of frustrated breathing movements can be distinguished from other causes.

[0027] During assisted ventilation, it is also possible that the device used for this purpose cannot recognize the initial inhalation or exhalation process of the organism or recognizes the initial inhalation or exhalation process of the organism at the wrong time point due to the trigger. In order to identify the breathing phase, an inhalation and / or exhalation trigger is usually used in such a device, which recognizes the alternation of the breathing direction of the organism according to the pressure or airflow change measured at the end of the inhalation or exhalation phase and starts the corresponding inhalation or exhalation mode of the device, so as to, for example, generate a counterpressure or a pressure different from the pressure existing during the inhalation to assist the patient to exhale. The sensitivity of this inhalation and / or exhalation trigger is variable and especially adjustable in practice, because depending on the state of the organism, such as the sleeping state or the awake state, the characteristics of the initial inhalation or exhalation can be expressed in different intensities. The misrecognition of the actual ventilation phase of the organism by the device due to too high or too low trigger sensitivity is called insufficient trigger. This insufficient trigger determined by parameters can appear as insufficient inhalation trigger and / or insufficient exhalation trigger. For example, an overly sensitive setting may cause an early start of the inhalation mode contrary to the patient's intention due to slight pressure fluctuations, while an overly insensitive setting may cause the exhalation mode to be too late or even skipped. Worse still, the trigger sensitivity is, for example, affected by leakage of the device or the organism, such as by a mouth or mask leak or a technical leak of the device. In particular, this may lead to insufficient triggers of the inhalation trigger due to leakage. When such a leak exists, the device automatically generates a higher counterpressure to compensate for the leak, so that the inhalation trigger of the device cannot recognize the negative pressure that may be induced by the patient at the beginning of the inhalation. The frustrated respiratory movement caused by insufficient triggers can be read according to the characteristic features of the respiratory pressure change curve and / or the respiratory airflow change curve, wherein the insufficient triggers determined by the parameters and caused by the leak can be distinguished as the cause of the frustrated respiratory movement and distinguished from other causes (such as intrinsic PEEP). The device can also be set up to determine the insufficient triggers caused by the leak by means of a measurable leak value of the device and, for example, compare the measured leak value with the leak value from the previous respiratory cycle.

[0028] Thus, the programmable control unit can identify the cause of the frustrated breathing movement, respectively, based on the different characteristic features of the frustrated breathing movement that occurs due to insufficient intrinsic PEEP or insufficient trigger. Insufficient trigger and also intrinsic PEEP can lead to phase differences between the actual ventilation phase of the living being and the ventilation phase performed by the device. For example, the phase difference can be identified by the device based on characteristic features in the respiratory pressure change curve and / or the respiratory airflow change curve.

[0029] According to an advantageous embodiment, the programmable control unit is configured to differentiate between frustrated breathing movements due to insufficient triggering caused by leakage and frustrated breathing movements due to insufficient triggering determined by parameters, based on characteristic features of the respiratory pressure curve and / or the respiratory airflow curve. The control unit is thus suitable for further identifying and distinguishing between the two possible causes of insufficient triggering that occur.

[0030] A trigger shortage due to leakage may occur, for example, due to a mask leak or a technical leak of the device. The leakage value of the device is, for example, related to the treatment pressure and is determined based on empirical values ​​or measurements and incorporated into the control calculation as a correction value. In this case, inaccuracies may occur, for example due to the assumptions made and the averaged values, which may indirectly affect the sensitivity of the inhalation and exhalation triggers. Such a trigger shortage due to leakage can be identified based on characteristic features of the respiratory pressure curve and / or the respiratory air flow curve, for example, in the exhalation phase based on an increase in the respiratory air flow that appears as a dome during the increase in the respiratory air flow curve and an increase in the respiratory pressure that appears as a dome that occurs essentially at the same time.

[0031] Parameter-dependent under-triggering occurs due to inaccurate presetting of the trigger parameters of the programmable control unit, so that the inhalation and / or exhalation trigger is set too sensitive or too insensitive. This is a trigger under-triggering that is directly influenced by the specific device settings. Parameter-dependent under-triggering can be identified based on characteristic features of the respiratory pressure change curve and / or the respiratory air flow change curve, for example, in the exhalation phase based on the increase in respiratory air flow during the increase in respiratory air flow, which is manifested as a convex portion and the respiratory pressure change in the form of a respiratory pressure drop with a peak shape that occurs during this increase in respiratory air flow, and the subsequent increase in respiratory pressure with a peak shape in the respiratory pressure change curve during the increase in respiratory air flow.

[0032] Since the programmable control unit can distinguish between insufficient triggers due to leakage and insufficient triggers determined by parameters, the control unit can be set up to initiate corresponding appropriate countermeasures. For example, when insufficient triggers due to leakage are identified, the programmable control unit can adjust the above correction value in a suitable manner to take into account the leakage value or can also dynamically control until insufficient triggers due to leakage are no longer recognized based on the characteristic features of the respiratory airflow change curve and / or the respiratory air pressure change curve. On the other hand, when insufficient triggers determined by parameters are identified, the programmable control unit can autonomously adjust the pre-set parameter group for the inhalation and / or exhalation trigger in a suitable manner, request the user to change the parameter group or also perform dynamic control of the parameters until insufficient triggers determined by parameters are no longer recognized based on the characteristic features of the respiratory airflow change curve and / or the respiratory air pressure change curve.

[0033] According to an advantageous embodiment, a programmable control unit is set up to identify frustrated respiratory movement according to the shape of the increase or decrease of respiratory pressure and / or respiratory airflow in the time point, time period and / or respiratory pressure variation curve and / or respiratory airflow variation curve. For example, in the exhalation phase, in the first half or second half of the exhalation phase or in the transition from the inhalation phase to the exhalation phase, the time point at which the respiratory pressure and / or respiratory airflow increases or decreases can be used as a characteristic feature of frustrated respiratory movement. In this case, it is shown according to experience that the features characterizing frustrated respiratory movement appear more and more in the exhalation section of the respiratory pressure variation curve and / or respiratory airflow variation curve. The duration of the increase or decrease of respiratory pressure and / or respiratory airflow, which can usually be 0.1 seconds to 1.0 seconds, can also be used as a characteristic feature of frustrated respiratory movement. With regard to the shape, the increase or decrease of respiratory pressure and / or respiratory airflow can be configured as, for example, an arch or a peak. An arch represents an increase or decrease in the shape of an arc; in the case of a peak, the increase or decrease has an inflection point, in particular an acute-angled inflection point between the variation curves that rise before the maximum and fall after the maximum. During the evaluation, a plurality of the above criteria can also be linked to one another, for example, when an increase or decrease in the respiratory pressure and / or respiratory airflow that is formed as an arch occurs in the middle of the exhalation phase recognized by the device between 0.2 seconds and 0.7 seconds, it can be inferred that a frustrated breathing movement is present. In order to identify and distinguish the above variation curves, it is also possible to use maxima, minima, turning points, saddle points, amplitudes, integrals and / or derivatives that occur at predefined time points and / or time periods of the respiratory pressure variation curve and / or respiratory airflow variation curve.

[0034] The device is particularly designed to distinguish frustrated respiratory movements that occur due to intrinsic PEEP of the organism from frustrated respiratory movements that occur due to insufficient triggers based on the time points, time periods and / or the shape of the increase or decrease of respiratory pressure and / or respiratory airflow in the respiratory pressure change curve and / or the respiratory airflow change curve. This distinguishability is based on the knowledge that the characteristic features of frustrated respiratory movements caused by intrinsic PEEP or insufficient triggers differ from each other, in particular in terms of the time points, time periods and / or the shape of the increase or decrease of respiratory pressure and / or respiratory airflow.

[0035] According to an advantageous embodiment, the programmable control unit is set up to identify frustrated breathing movements based on characteristic features of the respiratory airflow change curve and characteristic features of the respiratory pressure change curve associated therewith. The recognition accuracy is thereby improved. For example, the control unit first determines that the respiratory airflow in the respiratory airflow change curve has increased, and then checks whether there is an increase in respiratory pressure in the respiratory pressure change curve in a preset time period before, after or at the same time as the time point of the increase in respiratory pressure. In addition to the time point, the time period and shape of the increase in respiratory pressure and respiratory airflow that occurs may also be correlated with each other. Therefore, in terms of multi-factor correlation, it is possible to perform recognition in a combined manner based on the characteristic features of the respiratory airflow change curve and the respiratory pressure change curve.

[0036] The programmable control unit is particularly designed to distinguish frustrated breathing movements due to the endogenous PEEP of the organism and frustrated breathing movements due to insufficient triggers based on the characteristic features of the respiratory airflow change curve and the characteristic features of the respiratory pressure change curve associated therewith. The accuracy of the distinction is improved thereby. For example, the control unit first determines the increase in the respiratory airflow present as an arch in the respiratory airflow change curve, and then checks whether there is an increase in the respiratory pressure formed as an arch at substantially the same time point and during substantially the same time period. If this is the case, the control unit recognizes in this respect the frustrated breathing movements caused by insufficient triggers due to leakage. In particular, the simultaneous increases in the respiratory airflow and respiratory pressure change curves can have substantially the same shape, for example, have the same slope at the same time point or have substantially the same integral with respect to the time of the corresponding increase.

[0037] Furthermore, the control unit can also first determine the increase in the respiratory airflow present as a curve in the respiratory airflow profile and then check whether a respiratory pressure increase in the form of a peak is present within a predefined time period, for example before the end of the time or during the second half of the increase in the respiratory airflow. If this is the case, the control unit in this respect detects frustrated breathing movements due to intrinsic PEEP. In particular, the peak in the respiratory pressure profile can be smaller than the curve in the respiratory airflow profile, for example with a smaller integral over the time of the increase.

[0038] In another characteristic feature combination of frustrated breathing movements due to insufficient triggering, there is a breathing air flow increase in the form of a curve in the breathing air flow curve, while within the same time period of the breathing air flow increase, a breathing pressure drop in the form of a peak occurs first and then a breathing pressure increase in the form of a peak occurs. If this is the case, the control unit detects in this respect a frustrated breathing movement due to insufficient triggering determined by the parameters. In particular, the peak in the breathing pressure can be smaller than the curve in the breathing air flow curve, for example, it can have a smaller integral over the time of the increase.

[0039] The programmable control unit is designed to recognize characteristic features and evaluate them in relation to one another in order to detect frustrated breathing movements and to differentiate between intrinsic PEEP and insufficient triggering, depending on their causes.

[0040] According to an advantageous embodiment, the programmable control unit is also set up to perform oscillometric airway resistance measurement. Performing oscillometric airway resistance measurement can simplify the identification of the biological endogenous PEEP, so that a better distinction can be made between frustrated respiratory movements due to the biological endogenous PEEP and frustrated respiratory movements due to insufficient triggers. Oscillometric airway resistance measurement can be achieved by corresponding manipulation of the air delivery unit without the need for additional equipment components. In the oscillometric airway resistance measurement, the airway resistance measurement is known, for example, in the form of so-called pulse oscillometric method (IOS) or forced oscillation technology (FOT), where the ventilation pressure generated by the device is superimposed with a small amplitude, high-frequency pressure pulse. According to the ratio of the pressure difference measured in this case to the respiratory flow, the flow resistance and thus the airway resistance can be determined. The biological endogenous PEEP can be inferred indirectly or directly from the airway resistance. Therefore, the identification and differentiation accuracy of the device for frustrated respiratory movements caused by endogenous PEEP or insufficient triggers is improved.

[0041] According to an advantageous embodiment, the programmable control unit is designed to determine the frequency and / or intensity of the intrinsic PEEP or the trigger deficiency that leads to the occurrence of frustrated breathing movements. For this purpose, the control unit can determine and evaluate, for example, the time extension, amplitude, slope, integral and number of occurring increases or decreases in the breathing pressure and / or breathing airflow, for example by comparison with reference values ​​or threshold values. The analysis can also be carried out in particular over a plurality of breathing cycles, for example in order to distinguish between recurring symptoms and one-time irregularities or to observe an increase or decrease in symptoms.

[0042] In this case, according to an advantageous embodiment, the programmable control unit is designed to output, when preset threshold values ​​for the frequency and / or intensity of the intrinsic PEEP or the insufficiency of the trigger are exceeded, for example, an optical, acoustic and / or tactile warning signal in order to indicate, for example, that a health-critical state has been reached and to enable the living being or other persons present to initiate an appropriate reaction, for example an emergency call.

[0043] According to an advantageous embodiment, the programmable control unit is designed to automatically change the control parameters of the air delivery unit when a frustrated breathing movement is detected. Thus, the device itself can already initiate suitable countermeasures to reduce or avoid further frustrated breathing movements.

[0044] According to an advantageous embodiment, the programmable control unit is set up to continuously, controllably, and automatically change the control parameters of the air delivery unit to reduce and / or eliminate the characteristics of the respiratory air pressure change curve and / or the respiratory air flow change curve that characterize the frustrated breathing movement. In this case, the device itself iteratively approaches the most favorable air flow parameters for the patient by continuously changing the control parameters in the sense of the control loop. For example, roughly in an exhalation phase or continuously in multiple exhalation phases, the dynamic counter-air pressure generated by the air delivery unit is increased or reduced in the following time period incrementally or intermittently until the occurrence of frustrated breathing movement is recognized by the programmable control device based on the characteristic characteristics of the respiratory air pressure change curve and / or the respiratory air flow change curve, and the time period is shorter than the exhalation phase. When the frustrated breathing movement is identified, the induced air pressure is then slightly reduced or increased again, or an intermittent air pressure increase is started later, and it is checked whether further frustrated breathing movements occur. This process can be repeated at any frequency so as to obtain suitable control parameters at any time point, which reduce or avoid the occurrence of frustrated breathing movements. In this way, it is possible, for example, that a doctor or therapist only sets the value range of IPAP and EPAP and optionally the auxiliary frequency of breathing at the device, and the device itself determines and sets the most favorable IPAP and / or EPAP value and other parameters for avoiding frustrated breathing movements at the moment according to the respiratory airflow change curve and the respiratory air pressure change curve. The auxiliary frequency can be the minimum respiratory frequency that guarantees a sufficient number of breaths of the biological being.

[0045] The continuous, controlled, automatic change of the control parameters is based on a methodological approach that is fundamentally different from the methodological approach that is common in current ventilation concepts, which aims to eliminate frustrated breathing movements, especially those caused by intrinsic PEEP or insufficient triggers, as a control purpose. Therefore, current guidelines on non-invasive ventilation are mainly oriented to pCO2 values ​​as a control criterion, wherein especially high pressure amplitudes should promote CO2 exchange in patients. In contrast, according to the above-mentioned embodiment, for example, pressure values, especially IPAP, should only be controlled in such a way that frustrated breathing movements no longer occur, because such controlled assisted ventilation improves the well-being of the organism and avoids damaging effects of excessively high pressures on the lungs.

[0046] The programmable control unit can be configured to automatically change the control parameters of the air delivery unit in order to reduce the features of the respiratory pressure profile and / or the respiratory air flow profile that characterize frustrated respiratory movements in accordance with a preset intrinsic minimum PEEP. In this way, a specific, permitted intrinsic basic or minimum PEEP (minimum PEEP) can be set for specific applications and organisms, such as patients with significantly elevated pCO2 values, which is not fallen below during the automatic change of the control parameters of the air delivery unit in order to reduce the features of the respiratory pressure profile and / or the respiratory air flow profile that characterize frustrated respiratory movements.

[0047] In this case, the programmable control unit can be set up to determine a preset endogenous minimum PEEP based on a pCO2 measurement. "pCO2" in this case means the partial pressure of carbon dioxide, which reflects the amount of carbon dioxide dissolved in the blood of the organism. The control unit can, for example, determine the endogenous minimum PEEP based on the measured pCO2 value or pCO2 value range and the information or calculation instructions stored in the control unit and automatically change the control parameters so that it does not fall below the endogenous minimum PEEP. In order to check this condition and control it, the control unit can be set up to use the measured pCO2 value and / or the respiratory pressure change curve and / or the respiratory airflow change curve to characterize the characteristics of the frustrated respiratory movement. The control unit can be set up for continuous pCO2 measurement. The device can have at least one pCO2 sensor for determining, in particular constantly or continuously, the pCO2 value of the organism. The pCO2 sensor can be set up for transcutaneous or end-tidal measurement of the pCO2 value.

[0048] For example, the control parameter can also be an inhalation trigger or an exhalation trigger for switching the device from an inhalation mode to an exhalation mode or vice versa. Thus, for example, when a frustrated breathing movement due to insufficient triggering is detected, the sensitivity of the inhalation trigger or the exhalation trigger can be automatically increased or decreased by the programmable control device. For example, the sensitivity of the inhalation trigger or the exhalation trigger is increased or decreased until the programmable control unit no longer detects a frustrated breathing movement due to insufficient triggering.

[0049] A change in the sensitivity of the inhalation or exhalation trigger can also be performed as a response to frustrated breathing movements caused by intrinsic PEEP. In devices for assisted ventilation, the ratio of the current respiratory flow to the maximum respiratory flow is usually used as a switching criterion. When intrinsic PEEP occurs, the ratio can be increased so that the inhalation is switched to the exhalation more quickly. The intrinsic PEEP is thereby reduced. The ratio can then be reset to the original value or reduced until the characteristics characterizing the intrinsic PEEP can be recognized again.

[0050] The control parameters can also be a respiratory pressure profile and / or a respiratory air flow profile of the air delivered by the air delivery unit, which is preset by the programmable control unit. Thus, for example, the air flow provided by the air delivery unit can be reduced or increased in order to assist the breathing effort of the living being in a suitable manner. Different, respectively suitable increases or decreases in the respiratory pressure and / or increases or decreases in the respiratory air flow per unit time or different minimum and maximum values ​​for the respiratory pressure and the respiratory air flow can also be set by the control device.

[0051] The control parameter can also be an air pressure profile and / or air flow profile of the air delivered by the air delivery unit, which is preset by the programmable control unit. Thus, for example, the air flow provided by the air delivery unit can be reduced or increased in order to assist the breathing effort of the living being in a suitable manner. Different, respectively suitable increases or decreases in air pressure and / or increases or decreases in air flow per unit time or different minimum and maximum values ​​for air pressure and air flow can also be set by the control device.

[0052] Other control parameters can also be, for example, the inspiratory time or expiratory time preset by the programmable control device, in particular the corresponding minimum or maximum inspiratory time or expiratory time, IPAP value, EPAP value, pressure increase time (time to reach IPAP after triggering inspiration) and pressure reduction time (time to reach EPAP after triggering exhalation). The mentioned control parameters are particularly suitable for reducing or avoiding frustrated breathing movements due to intrinsic PEEP. Indirect parameters such as the preset breath volume that can be influenced by the above parameters can also be included as open-loop control or closed-loop control variables.

[0053] According to an advantageous embodiment, the programmable control unit can be set up to automatically reduce the auxiliary frequency and / or IPAP value and / or maximum inspiratory time and / or automatically increase the exhalation trigger sensitivity when frustrating respiratory movements due to the biological endogenous PEEP are detected. Alternatively or additionally, the programmable control unit can be set up to automatically increase the auxiliary frequency and / or IPAP value and / or maximum inspiratory time and / or automatically reduce the exhalation trigger sensitivity after eliminating the frustrating respiratory movements due to the biological endogenous PEEP. It is also advantageous that the programmable control unit is set up to automatically increase the auxiliary frequency and / or IPAP value and / or maximum inspiratory time and / or automatically reduce the exhalation trigger sensitivity until the frustrating respiratory movements due to the biological endogenous PEEP are detected. In this way, the control unit automatically sets the optimal operating point of the device at all times according to the four mentioned parameters with high user comfort.

[0054] The breathing pressure and / or breathing air flow curve preset by a programmable control unit is particularly important for a ventilation device with a debloating function. The air pressure and / or air flow curve preset by a programmable control unit is particularly important for a ventilation device with a debloating function. Such a ventilation device generates a counterpressure when the patient exhales. Through the provided breathing resistance, the air pressure or breathing air pressure in the respiratory tract of the organism is intermittently increased and prevents the respiratory tract from closing. For example, the exhalation phase of the organism can be assisted in the following manner: during the exhalation phase, the air pressure or breathing air pressure in the respiratory organ is regulated according to the respiratory air flow or the exhalation parameters derived therefrom, so that the respiratory air flow flowing out of the organism reaches a predetermined level. Therefore, instead of setting a preset pressure as in known ventilation devices, the air pressure or breathing air pressure is dynamically regulated according to the respiratory air flow of exhalation, so that a specific exhalation air flow can be guaranteed. In this case, the air pressure or breathing pressure can be increased or decreased as required, wherein by regulating the air pressure or breathing pressure according to the respiratory airflow, a corresponding minimum pressure in the respiratory organ can be dynamically maintained as a variable counterpressure, so that the small airways and their branches to the alveoli remain open. Therefore, a certain dynamic resistance is achieved during exhalation, which is unexpectedly felt by the patient as pleasant and auxiliary. Therefore, improved exhalation is achieved and undesirable excessive distension of the lungs is avoided. In particular, relatively short pressure pulses during exhalation are already helpful in opening the airways. The counterpressure is especially the air pressure loading that is increased and decreased again during the exhalation phase and is opposite to the respiratory flow of the organism by the device at least in sections.

[0055] However, if the air cannot be sufficiently released from the respiratory tract and lungs of the living being due to the impending counterpressure of the ventilator, the resistance generated by the debloating function of the device may also lead to the above-mentioned intrinsic PEEP. Therefore, it is important for ventilators with an integrated debloating function to recognize the occurrence of frustrated breathing movements and, in response, for example, to change the set counterpressure parameters, such as the counterpressure waiting time or the counterpressure amplitude, or, for example, also activate or deactivate dynamic counterpressure regulation. Accordingly, according to an advantageous embodiment of the invention, the control parameters are the counterpressure and / or the counterpressure variation curve preset by the programmable control unit and / or the counterpressure amplitude and / or the counterpressure waiting time during the exhalation phase preset by the programmable control unit. The counterpressure waiting time is the delay in the build-up of the counterpressure after the change from the inspiration phase to the exhalation phase; for example, the counterpressure waiting time is between 0 seconds and 0.8 seconds after the start of exhalation. According to an advantageous embodiment, the backpressure amplitude and / or the backpressure waiting time during the exhalation phase can be set in relation to one another and / or as a function of the IPAP value or IPAP value range and / or the pressure difference from IPAP to EPAP. The higher the IPAP value or the larger the permissible IPAP value range is selected, the longer the backpressure waiting time can be. The backpressure amplitude, i.e. the maximum backpressure value, can be changed as a function of the current breathing pressure and the backpressure waiting time. The higher the IPAP value or the larger the permissible IPAP value range is selected, the larger the backpressure amplitude can be. The correlation between the backpressure waiting time, the backpressure amplitude and the IPAP value can be stored in particular in a programmable control unit. In this way, the programmable control unit can be set up to automatically determine and set the optimal backpressure waiting time and the optimal backpressure amplitude as a function of the IPAP value set by external input. In this case, preferably, the higher the IPAP value input or controlled, the longer the backpressure waiting time and the higher the backpressure amplitude are selected by the control unit. The temporal backpressure variation curve can also be changed so that, for example, the maximum backpressure is reached or left earlier or later. Generally, a higher back pressure results in a longer exhalation time. However, a back pressure that is too high can make exhalation difficult, so that it is advantageous to adjust the back pressure parameter according to the occurrence of frustrated breathing movements.

[0056] In practice, it cannot be ruled out that intrinsic PEEP and insufficient trigger may occur simultaneously and influence or aggravate each other. For example, the sensitivity of the inhalation trigger to the increased intrinsic PEEP may be too weak because the residual pressure in the airway covers the negative pressure established by the organism for inhalation. In addition, strongly manifested respiratory movements, leakage and / or simultaneous intrinsic PEEP will overlap each other, and it becomes difficult to identify frustrated respiratory movements based on the characteristic features in the respiratory airflow change curve and the respiratory pressure change curve. In order to alleviate the above symptoms, it would be effective in this case to preventively start a variety of countermeasures in combination, such as reducing IPAP, shortening the back pressure waiting time and reducing the back pressure. Thus, leakage and intrinsic PEEP are reduced at the same time. Alternatively or additionally, the above-mentioned execution of the oscillometric airway resistance measurement will be advantageous in distinguishing between intrinsic PEEP and insufficient triggers.

[0057] According to an advantageous embodiment, the programmable control unit can also be set up to identify the inspiratory inhibition of the organism based on the characteristic features of the respiratory pressure change curve and / or the respiratory airflow change curve. Compared with frustrated respiratory movements, there is no stage difference in inspiratory inhibition, but a reduced or even interrupted respiratory airflow of the organism is caused during inspiration. Inspiratory inhibition can occur reflexively, for example, through sensitive protective reflexes, such as the Hering-Breuer reflex. The characteristic features of this inspiratory inhibition can be manifested in the detected respiratory pressure change curve and / or respiratory airflow change curve, for example, as a respiratory airflow change curve that drops sharply during the unchanged IPAP level in the early inspiration phase. In response to the identified inspiratory inhibition, the programmable control unit can be set up to automatically change the control parameters of the air delivery unit, and for example, adjust the preset respiratory pressure change curve and / or respiratory airflow change curve of the air delivered by the air delivery unit in an appropriate manner, especially also adjust the pressure rise time, until the characteristic features of inspiratory inhibition no longer appear. Alternatively or at the same time, the IPAP can also be reduced. Alternatively or additionally, the device can also output an optical, acoustic and / or haptic warning signal to indicate the inhalation inhibition.

[0058] Characteristic features of the respiratory pressure change curve and / or the respiratory airflow change curve can also be regarded as characteristic patterns, especially when they are observed or evaluated in relation to each other, because the characteristic features can repeatedly appear in the same or similar manifestations during frustrated breathing movements. According to an advantageous embodiment, the programmable control unit has a pattern recognition unit for identifying characteristic features of the respiratory pressure change curve and / or the respiratory airflow change curve. The programmable control unit can be equipped with corresponding pattern recognition and / or classification software, for example, which can be used with the help of principal component analysis, discriminant analysis or support vector machine calculation of pattern recognition and classification processes. The use of artificial neural networks is also advantageous.

[0059] Similar to the device for assisted ventilation of a living being according to the present invention, the present invention also includes a method for assisted ventilation of a living being using a ventilation device, wherein the breathing pressure values ​​and breathing airflow values ​​of the living being that are successive in time are detected by means of a pressure sensor and an airflow sensor of the ventilation device, and the breathing pressure change curve and the breathing airflow change curve formed from the breathing pressure values ​​and the breathing airflow values ​​are evaluated by means of a programmable control unit of the ventilation device, and wherein frustrated breathing movements of the living being are identified based on characteristic features of the breathing pressure change curve and / or the breathing airflow change curve. The advantages described above can also be achieved thereby. The ventilation device can be configured as a device of the type described above.

[0060] In this case, the characteristic feature can be a maximum value, a minimum value, a turning point, a saddle point, an amplitude, an integral and / or a derivative of the respiratory air pressure variation curve and / or the respiratory air flow variation curve at a predetermined time point and / or time period. The characteristic feature can also be a characteristic deviation from a preset reference respiratory air pressure variation curve and / or a reference respiratory air flow variation curve.

[0061] The method may include storing a preset reference respiratory pressure variation curve and / or a reference respiratory airflow variation curve and / or a reference feature of a characteristic feature of frustrated respiratory movement in a memory unit of a programmable control unit. In particular, different disease-specific reference respiratory pressure variation curves and / or reference respiratory airflow variation curves and / or different disease-specific reference features of a characteristic feature of frustrated respiratory movement may be stored in the memory unit.

[0062] The method can include identifying frustrated breathing movements of the living being based on phase differences occurring between an actual breathing phase of the living being and a breathing phase performed by a ventilator.

[0063] The method can include distinguishing between frustrated breathing movements that occur due to intrinsic PEEP of the organism and frustrated breathing movements that occur due to insufficient triggering based on characteristic features of the respiratory pressure profile and / or the respiratory airflow profile.

[0064] The method can include distinguishing, based on characteristic features of the respiratory pressure curve and / or the respiratory air flow curve, between frustrated respiratory movements that occur due to insufficient triggering due to a leak and frustrated respiratory movements that occur due to insufficient triggering due to parameters.

[0065] The method may include: identifying frustrated respiratory movements based on the time points, time periods and / or shapes of increases or decreases in respiratory pressure and / or increases or decreases in respiratory airflow in a respiratory pressure change curve and / or a respiratory airflow change curve, and in particular for distinguishing frustrated respiratory movements occurring due to intrinsic PEEP of the organism from frustrated respiratory movements occurring due to insufficient triggers based on the time points, time periods and / or shapes of increases or decreases in respiratory pressure and / or increases or decreases in respiratory airflow in a respiratory pressure change curve and / or a respiratory airflow change curve.

[0066] The method may include identifying frustrated breathing movements based on characteristic features of the respiratory airflow curve and of the associated respiratory pressure curve, and in particular distinguishing frustrated breathing movements that occur due to intrinsic PEEP of the organism from frustrated breathing movements that occur due to insufficient triggering.

[0067] Furthermore, the method can also include performing an oscillometric airway resistance measurement.

[0068] The method can include determining the frequency and / or intensity of insufficient intrinsic PEEP or trigger. In this case, when a predetermined threshold value for the frequency and / or intensity of insufficient intrinsic PEEP or trigger is exceeded, an especially acoustic, optical and / or haptic warning signal can be output.

[0069] The method can include automatically changing a control parameter of the air delivery unit when a frustrated breathing movement is detected. In particular, a continuous, controlled, automatic change of the control parameter of the air delivery unit can be performed to reduce and / or eliminate features of the respiratory pressure curve and / or respiratory air flow curve that characterize frustrated breathing movements.

[0070] The method can include automatically changing the control parameters of the air delivery unit according to a preset intrinsic minimum PEEP to reduce the features of the respiratory pressure curve and / or the respiratory air flow curve that characterize frustrated respiratory movement. In this case, the preset intrinsic minimum PEEP can be determined according to the pCO2 measurement value.

[0071] Suitable control parameters are, for example, an inhalation trigger or an exhalation trigger for changing the device from an inhalation mode to an exhalation mode or vice versa. Another suitable control parameter is, for example, a respiratory air pressure variation curve and / or a respiratory air flow variation curve of the air delivered by the air delivery unit, which is preset by the programmable control unit. Another suitable control parameter is, for example, a pressure variation curve and / or an air flow variation curve of the air delivered by the air delivery unit, which is preset by the programmable control unit. The control parameter can also be a backpressure and / or a backpressure variation curve preset by the programmable control unit during the exhalation phase and / or a backpressure amplitude and / or a backpressure waiting time preset by the programmable control unit. In this case, the backpressure amplitude and / or the backpressure waiting time during the exhalation phase can be set in relation to each other and / or according to the IPAP value or IPAP value range and / or according to the pressure difference from IPAP to EPAP.

[0072] The method may include: automatically reducing the IPAP value and / or the maximum inspiratory time and / or automatically increasing the exhalation trigger sensitivity when a frustrated breathing movement due to the intrinsic PEEP of the biological being is detected. Alternatively or additionally, the method may include: automatically increasing the IPAP value and / or the maximum inspiratory time and / or automatically reducing the exhalation trigger sensitivity after eliminating the frustrated breathing movement due to the intrinsic PEEP of the biological being.

[0073] The method may include detecting an inhalation inhibition of the biological subject based on characteristic features of the respiratory pressure profile and / or the respiratory air flow profile.

[0074] The method may include pattern recognition for identifying characteristic features of the respiratory pressure profile and / or the respiratory air flow profile.

[0075] The object of the invention is also achieved by a computer program with program code means, which is designed to: when the computer program is executed on a computing unit of a ventilator, execute a method for assisted ventilation of a living being using a ventilator, wherein temporally successive respiratory pressure values ​​and respiratory airflow values ​​of the living being are detected by means of a pressure sensor and an air flow sensor of the ventilator, and a respiratory pressure variation curve and a respiratory airflow variation curve formed from the respiratory pressure values ​​and respiratory airflow values ​​are evaluated by means of a programmable control unit of the ventilator, and wherein frustrated respiratory movements of the living being are detected based on characteristic features of the respiratory pressure variation curve and / or the respiratory airflow variation curve, and in particular the causes thereof are distinguished, for example due to an intrinsic PEEP of the living being or due to insufficient triggering. The advantages explained above can also be achieved thereby. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] The present invention will be described in detail below with reference to the embodiments using the accompanying drawings. The accompanying drawings schematically show:

[0077] Figure 1 An apparatus for assisted ventilation of a living being is shown;

[0078] Figure 2 Shows the usual breathing pressure change curve and breathing airflow change curve;

[0079] Figures 3 to 5 showing a respiratory pressure change curve and a respiratory air flow change curve with respect to time during a respiratory cycle with a recognizable frustrated respiratory movement and during a respiratory cycle without a recognizable frustrated respiratory movement;

[0080] Figures 6 to 8 A curve showing the change in respiratory pressure with respect to time during a respiratory cycle when the debloating function of the device is activated; and

[0081] Fig. 9 An actually recorded respiratory pressure curve and respiratory air flow curve with recognizable frustrated respiratory movements is shown. DETAILED DESCRIPTION

[0082] Figure 1 A device 1 for assisted ventilation of a living being 3 is shown. The device 1 has a hose 8 and a breathing mask 2 or another suitable interface for connecting the device 1 to the living being 3. For this purpose, the breathing mask 2 can be connected, for example, to the mouth and / or nose of the living being 3 or to the deeper respiratory tract. The breathing mask 2 has an outlet 4 open to the atmosphere, which is connected to the hose 8 via a throttle 5. In this way, a defined leakage can be set in the breathing mask 2.

[0083] The device 1 has a controllable air supply unit 6 with a fan for generating the excess pressure required for assisted ventilation in the respiratory organs of the living being 3. For example, air is sucked in from an air inlet 7 connected to the atmosphere via the air supply unit 6 and accordingly supplied in a compressed manner via a hose 8 to the breathing mask 2 and thus to the living being 3.

[0084] The device 1 has a sensor device with a pressure sensor 9 and an air flow sensor 11, which is designed to detect respiratory pressure values ​​and respiratory air flow values ​​of the living being 3 in succession in time. Alternatively or additionally, the air delivery unit 6 can have an integrated pneumotachometer for pressure and / or volume flow measurement.

[0085] The pressure sensor 9, the air flow sensor 11 and the air delivery unit 6 are connected to the programmable control unit 10 via electrical lines. The respiratory pressure change curve and the respiratory air flow change curve formed from the respiratory pressure values ​​and respiratory air flow values ​​detected by the pressure sensor 9 and the air flow sensor 11 and successively in time are evaluated by the programmable control unit 10. The programmable control unit 10 is set up to identify the frustrated respiratory movement of the organism 3 based on the characteristic features of the respiratory pressure change curve and / or the respiratory air flow change curve. The programmable control unit is also set up to determine the cause of the frustrated respiratory movement and optionally take corresponding measures to reduce or avoid the frustrated respiratory movement. To this end, the programmable control unit can optionally have a suitable storage unit, suitable software, a transmission mechanism and / or a pattern recognition unit (not shown in detail respectively).

[0086] Figure 2 The diagram in the upper part shows the respiratory pressure profile as a function of the pressure p over the time t. The diagram in the middle shows the respiratory pressure profile as a function of the volume flow t. The respiratory airflow curve as a function of time t. The lower diagram shows the chronological sequence of the ventilation mode of the device 1, that is, the ventilation phases T of the living being 3 by the device 1 during the respiratory cycle. I , T E The automatic identification of the obtained inspiratory pattern INSP and expiratory pattern EXSP. Only one inspiratory phase T is shown. I and an expiratory phase T E A complete breathing cycle, which can be regarded as a representative of the previous and subsequent breathing cycles. The breathing cycle starts at time t0 and ends at time t2. I To the exhalation phase T E The change of T is carried out at time t1 after approximately half of the breathing cycle. However, time t1 can also be significantly closer to t0, so that T I With T E The ratio of can also take values ​​of 1:2 to 1:4, or can be smaller. In individual cases, time point t1 can also be closer to t2. Figure 2 As can be seen, the inspiratory phase T I The breathing pressure in the breathing process is first increased continuously until the IPAP value p I Then, within a certain period of time, the IPAP value p I The pressure level remains approximately constant at the level of the inspiratory phase T I In contrast, during the exhalation phase, T EIn the present invention, the pressure build-up is no longer recorded, but the pressure maintained at the baseline pressure level of the respiratory cycle is recorded, currently at the EPAP value p E level. Figure 2 In addition, it can be seen that the respiratory airflow is in the inspiratory phase T I First, it continues to increase, and after reaching the local maximum, it is still in the inspiratory phase T I During the inspiratory phase, T I End or exhalation phase T E At the beginning, i.e. approximately at time t1, the respiratory airflow shifts to a value range below the initial level of the inhalation airflow, which indicates a change in the direction of the respiratory airflow of the living being. After reaching a local minimum, the respiratory airflow increases again until it reaches the initial value at the beginning of the respiratory cycle and then shifts to the next respiratory cycle. For example, the inhalation trigger of device 1 recognizes the exhalation T of living being 3. E End and / or inhale T I The exhalation trigger of the device 1 recognizes the inhalation T of the living being 3. I End and / or exhale T E The start of the inhalation mode INSP or the exhalation mode EXSP is ideally indicated here at the time t1, and the programmable control unit 10 is prompted to switch on the exhalation mode EXSP of the control unit 10. In the exhalation mode EXSP, the air delivery unit 6 can, for example, generate an overpressure with a preset pressure curve that assists the exhalation of the organism 3. Ideally, at the time t2, the control unit 10 ends the exhalation mode EXSP, for example based on a signal from an inhalation trigger. The idealized illustration of the switching time points of the two modes does not take into account any technically determined delay times, such as electronic switching times. The start or end of the inhalation mode INSP or the exhalation mode EXSP is not rigidly preset by the control unit 10, but is dynamically adapted to the breathing phase T of the organism 3 by identifying the corresponding breathing effort of the organism 3. I , T E .

[0087] Figures 3 to 5For comparison, respiratory pressure change curves and respiratory airflow change curves are shown, each with a respiratory cycle consisting of the patterns INSP and EXSP with frustrated respiratory motion and a subsequent respiratory cycle without frustrated respiratory motion. The change curves shown here have different characteristic features or feature combinations M1 to M4 of frustrated respiratory motion of the biological being 3. It should be pointed out that the characteristic features or feature combinations M1 to M4 shown here are, on the one hand, highly schematic in order to improve comprehensibility, and on the other hand, they are only selected examples that have been identified as characteristic feature manifestations in experiments.

[0088] exist Figures 3 to 5 In the first respiratory cycle with frustrated breathing movement, each begins at time t0 and ends at time t2. I To the exhalation phase T E The change of occurs at time t1. Characteristic features M1, M2, M3, M4 appear in the respiratory pressure change curve and / or the respiratory airflow change curve between time t3 and t4. The second respiratory cycle without frustrated respiratory movement starts at time t2 and ends at time t6. I To the exhalation phase T E The transformation occurs at time point t5.

[0089] exist Figure 3 As can be seen in the figure, during the exhalation phase T E During the increase of the respiratory airflow change curve between the time points t3 and t4, the increase in the respiratory airflow manifested as an arch appears as a characteristic feature M1. In the respiratory pressure change curve, the increase in the respiratory pressure manifested as an arch can be identified as another characteristic feature M2 essentially simultaneously with the characteristic feature M1. The features M1 and M2 can each be characteristic features of frustrated respiratory movement from their own point of view. However, they can also form a common characteristic feature of frustrated respiratory movement and can be evaluated in a related or mutually associated manner. Thus, for example, it can be concluded in the programmable control unit 10 that, with respect to the two-factor correlation, the presence of frustrated respiratory movement can only be inferred when the characteristic features M1 and M2 appear together.

[0090] It has been shown that the characteristic features M1 and M2 characterize not only frustrated breathing movements in general, but also frustrated breathing movements caused by insufficient triggers in particular. If the programmable control unit 10 detects a breathing airflow increase present as a curve in the breathing airflow curve and a breathing pressure increase present as a curve at the same time, which preferably also have substantially the same or similar slopes and / or integrals, the control unit 10 infers that frustrated breathing movements are present due to insufficient triggers.

[0091] Furthermore, it has been shown that the characteristic features M1 and M2 characterize not only a triggering deficiency but also, in particular, a triggering deficiency caused by a leak. The triggering deficiency shown is therefore caused by a leak or an insufficient correction value determined by the programmable control unit 10 for taking into account a leak value, such as a hood leak or a technical leak, and can be reduced or avoided autonomously by the programmable control unit 10 by corresponding countermeasures.

[0092] exist Figure 4 It can be seen that in the exhalation phase T of the respiratory airflow change curve E During the increase of the respiratory airflow between the time points t3 and t4, the increase of the respiratory airflow manifested as an arch appears as a characteristic feature M1. In the respiratory pressure change curve, between the time points t3 and t4, close to t4 in time, another characteristic feature M3 can be identified as the increase of the respiratory pressure manifested as a peak. The features M1 and M3 can each be characteristic features of frustrated respiratory movement from their own point of view. However, they can also form a common characteristic feature of frustrated respiratory movement and can be evaluated in a related or mutually associated manner. Thus, for example, it can be concluded in the programmable control unit 10 that, with respect to the two-factor correlation, the presence of frustrated respiratory movement can only be inferred when the characteristic features M1 and M3 appear together.

[0093] It has been shown that the characteristic features M1 and M3 characterize frustrated breathing movements in general, but in particular frustrated breathing movements caused by the intrinsic PEEP of the living being 3. If the programmable control unit 10 detects a breathing airflow increase present as a curve in the breathing airflow profile and a breathing pressure increase present simultaneously or during a temporally later part of the breathing airflow increase, which is formed as a peak, wherein the breathing pressure increase preferably has a smaller integral over the time of the increase than the breathing airflow increase, then the control unit 10 infers that frustrated breathing movements are present due to the intrinsic PEEP.

[0094] exist Figure 5 It can be seen that in the exhalation phase T of the respiratory airflow change curve EDuring the increase of the respiratory airflow between the time points t3 and t4, the increase of the respiratory airflow manifested as an arch appears as a characteristic feature M1. In the respiratory pressure change curve, a decrease in respiratory pressure manifested as a peak can be identified in the first half of the time period between the time points t3 and t4, while an increase in respiratory pressure manifested as a peak can be identified as a common characteristic feature M4 in the second half of the time period between the time points t3 and t4. Features M1 and M4 can each be a characteristic feature of frustrated respiratory movement from their own point of view. However, they can also form a common characteristic feature of frustrated respiratory movement and can be evaluated in a related or mutually associated manner. Therefore, for example, it can be concluded in the programmable control unit 10 that, with respect to the two-factor correlation, the presence of frustrated respiratory movement can only be inferred when the characteristic features M1 and M4 appear together.

[0095] It has been shown that the characteristic features M1 and M4 characterize not only frustrated breathing movements in general, but also frustrated breathing movements caused by insufficient triggers in particular. If the programmable control unit 10 detects a respiratory airflow increase present as a curve in the respiratory airflow profile and a respiratory pressure decrease present as a peak during the first half of the time period between the time points t3 and t4 and a respiratory pressure increase present as a peak in the second half of the time period between the time points t3 and t4, wherein the respiratory pressure increase preferably has a smaller integral over the time of the increase than the respiratory airflow increase, then the control unit 10 infers that a frustrated breathing movement is present due to insufficient triggers.

[0096] Furthermore, it has been shown that the characteristic features M1 and M4 characterize not only a trigger deficiency, but in particular a parameter-dependent trigger deficiency. The illustrated trigger deficiency is therefore caused by the preset parameter values ​​set by the programmable control unit 10 for the sensitivity of the inhalation and / or exhalation trigger and can be reduced or avoided by corresponding countermeasures, either autonomously by the control unit 10 or by external correction inputs.

[0097] exist Figures 6 to 8 , the respiratory pressure change curve over time during a respiratory cycle with an activated debloating function of the device 1 is shown by way of example. In this case, during the exhalation phase T of the respiratory cycle E In the breathing cycle, the device 1 generates a counterpressure, which provides breathing resistance for the living being 3 and thus enables more comfortable exhalation and prevents airway closure. The breathing cycle begins at time t0 with an increase in the breathing pressure to the IPAP value p I Inhalation ends at time t1 and exhalation begins, which ends at time t2. Between time t1 and t2, i.e. during exhalation, a counterpressure is generated by the device 1. In particular, the counterpressure is generated from the counterpressure start time t GATo the end time of the back pressure t GE is dynamically controlled. At time point t GA and t GE The maximum back pressure is reached between G .

[0098] exist Figure 6 In , this counterpressure is already generated with the start of exhalation at time t1, that is, there is no counterpressure waiting time after time t1. Figure 7 and Figure 8 In the process, the start delay of generating the back pressure is such that between time point t1 and time point t GA There is a time difference between the two. This time difference is called the back pressure waiting time T GW .exist Figure 8 In the middle, the back pressure waiting time T GW is set to Figure 7 In addition, Figures 6 to 8 Different IPAP values ​​p are selected in I and the back pressure amplitude p G The counterpressure parameters of the counterpressure generated by the device 1 are thus variably settable, preset by the programmable control unit 10 and / or dynamically adaptable to the respiratory airflow of the living being 3. The counterpressure parameters include in particular the counterpressure waiting time T GW , back pressure amplitude p G As well as the back pressure increase time and back pressure decrease time. Back pressure waiting time T GW is the time period between the point in time of the transition from the inspiratory phase to the expiratory phase and the start of the build-up of the counterpressure generated by the device 1. The counterpressure amplitude p G Describes the back pressure higher than at time t1+T GW The maximum pressure value of the pressure values ​​present at which the device 1 has not yet generated any counterpressure. Preferably, the counterpressure amplitude p G According to the back pressure waiting time T GW In addition, the back pressure waiting time T GW Preferably according to the IPAP value p I The back pressure change curve can be changed over time to meet the individual needs of the organism 3 for breathing resistance. Figure 6 Compared with the reverse pressure change curve in 7, Figure 8 The counterpressure curve in the embodiment has, for example, a less steep counterpressure drop time. Preferably, the counterpressure parameter is automatically regulated by the programmable control unit 10, so that the occurrence of frustrated breathing movements is avoided or at least reduced in the following way: when frustrated breathing movements are detected, the counterpressure parameter is changed in a suitable manner by the control unit 10 according to the characteristic features.

[0099] Fig. 9 The respiratory pressure change curve and the respiratory air flow change curve which are actually recorded according to the measured values ​​of the biological being 3 with recognizable frustrated breathing movements are shown. In this case, the respiratory pressure change curve can be seen from the upper diagram, while the respiratory air flow change curve can be seen from the lower diagram. It can be seen that in the respiratory air flow change curve, the respiratory air flow increase which occurs repeatedly as an arch in the exhalation phase of the biological being 3. By way of example, in the breathing cycle, the temporal start and end of the respiratory air flow increase are indicated by arrows A and B. In the respiratory pressure change curve, the respiratory pressure increase which repeatedly appears as a peak can be seen, wherein the peak of the respiratory pressure increase is significantly smaller than the respiratory air flow increase which appears as an arch. In addition, the respiratory pressure increase occurs in time at the end of the respiratory air flow increase which exists as an arch, as can be seen for the respiratory cycle selected by way of example by arrow C, which indicates the occurrence of the respiratory pressure increase. According to the temporal relationship between the respiratory air flow increase and the respiratory pressure increase and according to the shape of the corresponding increase, in Fig. 9 In this case, frustrated breathing due to intrinsic PEEP can be inferred.

Claims

1. A device for non-invasive assisted ventilation of a living being (3), comprising a sensor device, a programmable control unit (10) and an air delivery unit (6) which can be controlled by the control unit (10), ● wherein the sensor device comprises a pressure sensor (9) and an air flow sensor (11), which are designed to detect a respiratory pressure value and a respiratory air flow value of the living being (3) in succession in time, and wherein the programmable control unit (10) is configured to evaluate a respiratory pressure change curve and a respiratory air flow change curve, which are formed by respiratory pressure values ​​and respiratory air flow values ​​that are detected by the sensor device and that are sequential in time, It is characterized in that The programmable control unit (10) is configured to identify characteristic features in the respiratory pressure variation curve and the respiratory airflow variation curve and to identify frustrated respiratory movements of the living being (3) based on a characteristic feature of the respiratory airflow variation curve and a characteristic feature of the respiratory pressure variation curve associated therewith, and The programmable control unit (10) is designed to distinguish frustrated breathing movements occurring due to an intrinsic PEEP of the living being (3) from frustrated breathing movements occurring due to insufficient triggering, based on a characteristic feature of the respiratory airflow curve and a characteristic feature of the respiratory pressure curve associated therewith.

2. The device according to claim 1, characterized in that The characteristic feature is a maximum value, a minimum value, a turning point, a saddle point, an amplitude, an integral and / or a derivative at a predetermined time point and / or time period of the respiratory pressure variation curve and / or the respiratory air flow variation curve.

3. The device according to claim 1 or 2, characterized in that The characteristic feature is a characteristic deviation from a preset reference respiratory pressure variation curve and / or a reference respiratory air flow variation curve.

4. The device according to claim 1 or 2, characterized in that The programmable control unit (10) has a storage unit for storing a preset reference respiratory pressure variation curve and / or a reference respiratory airflow variation curve and / or a reference feature of a characteristic feature of frustrated respiratory movement.

5. The device according to claim 4, characterized in that The memory unit has different disease-specific reference respiratory pressure curves and / or reference respiratory airflow curves and / or different disease-specific reference features of characteristic features of frustrated respiratory movements.

6. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is designed to differentiate between frustrated respiratory movements due to a leak-induced trigger deficiency and frustrated respiratory movements due to a parameter-dependent trigger deficiency based on characteristic features of the respiratory pressure profile and the respiratory airflow profile.

7. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is designed to detect frustrated respiratory movements based on the time points, time periods and / or shapes of increases or decreases in respiratory pressure and / or increases or decreases in respiratory air flow in the respiratory pressure curve and the respiratory air flow curve.

8. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is also designed to carry out an oscillometric measurement of the airway resistance.

9. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is designed to determine the frequency and / or intensity of the intrinsic PEEP or the trigger deficiency.

10. The device according to claim 9, characterized in that The programmable control unit (10) is designed to output a warning signal when a predefined threshold value for the frequency and / or intensity of the intrinsic PEEP or the insufficient trigger is exceeded.

11. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is designed to automatically change control parameters of the air delivery unit (6) when frustrated breathing movements are detected.

12. The device according to claim 11, characterized in that The programmable control unit (10) is designed to continuously and automatically change the control parameters of the air delivery unit (6) in a controlled manner to reduce and / or eliminate features of the respiratory pressure variation curve and / or the respiratory air flow variation curve that characterize the frustrated respiratory movement.

13. The device according to claim 11, characterized in that The programmable control unit (10) is designed to automatically change the control parameters of the air delivery unit (6) to reduce the features of the respiratory pressure variation curve and / or the respiratory air flow variation curve that characterize the frustrated respiratory movement in accordance with a preset endogenous minimum PEEP.

14. The device according to claim 13, characterized in that The programmable control unit (10) is designed to determine a predefined intrinsic minimum PEEP based on a pCO2 measurement.

15. The device according to claim 11, characterized in that The control parameter is an inhalation trigger or an exhalation trigger for switching the device from an inhalation mode (INSP) to an exhalation mode (EXSP) or vice versa.

16. The device according to claim 11, characterized in that The control parameters are a breathing air pressure variation curve and / or a breathing air flow variation curve of the air delivered by the air delivery unit (6), wherein the breathing air pressure variation curve and / or the breathing air flow variation curve are preset by the programmable control unit (10).

17. The device according to claim 11, characterized in that The control parameter is a counterpressure and / or a counterpressure variation curve preset by the programmable control unit (10) and / or a counterpressure variation curve preset by the programmable control unit (10) during the exhalation phase (T E ) during the period of back pressure (p G ) and / or back pressure waiting time (T GW ).

18. The device according to claim 17, characterized in that The back pressure amplitude (p G ) and / or the back pressure waiting time (T GW ) can be correlated with each other and / or according to the IPAP value (p I ) or IPAP range and / or set according to the pressure difference from IPAP to EPAP.

19. The device according to claim 1 or 2, characterized in that The programmable control unit (10) automatically reduces the assistance rate and / or the IPAP value (p I ) and / or the maximum inspiratory time and / or automatically increase the exhalation trigger sensitivity, and / or the programmable control unit (10) is configured to automatically increase the assistance rate and / or IPAP value (p) after eliminating frustrated breathing movements due to the intrinsic PEEP of the biological (3). I ) and / or maximum inspiratory time and / or automatically reduce the exhalation trigger sensitivity.

20. The device according to claim 1 or 2, characterized in that The programmable control unit (10) has a pattern recognition unit for recognizing characteristic features of the respiratory pressure curve and / or the respiratory air flow curve.

21. The device according to claim 1 or 2, characterized in that The programmable control unit (10) is configured to distinguish between frustrated respiratory movements occurring due to an intrinsic PEEP of the biological subject (3) and frustrated respiratory movements occurring due to insufficient triggers based on the time points, time periods and / or shapes of increases or decreases in respiratory pressure and / or increases or decreases in the respiratory pressure change curve and the respiratory airflow change curve.

22. The device according to claim 10, characterized in that The warning signal is acoustic, optical and / or tactile.

23. The device according to claim 1 comprises a computer program having a program code structure, wherein the computer program is configured to execute a method for non-invasive assisted ventilation of a living being (3) using a ventilation device (1) when the computer program is executed on a computing unit of the ventilation device (1).

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