DE102017005629A1 - Ventilator for APAP ventilation - Google Patents

Abstract

The invention relates to a ventilator having a flow generator configured to deliver a breathing gas to a patient interface having a positive pressure; at least one sensor means arranged to provide a flow and / or pressure signal associated with the respiratory gas flow; and a controller configured to control the flow generator to generate a respiratory gas flow, wherein the controller provides a low base pressure of the respiratory gas, and wherein the controller is further configured to detect different events from the flow and / or pressure signal which may affect the patient's breathing gas supply, characterized in that the controller is configured to increase the base pressure in a first predetermined manner in response to the detection of at least one first event and the base pressure in a second predetermined response to the detection of at least a second event Increase way, which differs from the first way.

Description

The invention relates to a method and a device for controlling a respirator, in which different pressure levels for a respiratory gas supply can be predetermined and in which at least one respiration or respiratory parameter is detected by measurement and evaluated for controlling the ventilation pressure.

For the clinical picture of obstructive sleep apnea syndrome a determination of the individual pressure for CPAP therapy (continuous positive airway pressure, continuous positive airway pressure) is necessary. The CPAP therapy setting usually takes place during the so-called titration night by ventilation experts in the sleep laboratory. Alternatively, a CPAP device with automatic pressure regulation (Auto-CPAP device) can be used. Many patients with obstructive sleep apnea have a fluctuating need for pressure, and auto CPAP devices can help. They recognize at any time whether an obstruction develops and intervene in time with an increase in pressure, in order to prevent the occlusion of the airways.

From the EP 0 373 585 It is known to perform the breathing resistance of a patient by means of the ORM measurement. With a predefinable frequency, an oscillating volume flow with a small volume stroke is superimposed on the respiratory volume flow. From the periodic pressure fluctuation, a measured value dependent on the specific breathing resistance can be provided. The EP 0 705 615 describes a realization of a controller of a ventilator based on the performance of ORM measurements. EP 1 136 094 discloses an analysis of pressure signal and flux signal and ORM signal using pattern recognition to identify typical respiratory limitations. The DE 10 2007 011 924 describes the analysis of the flow signal for the identification of the respiratory phase of the patient and for the identification of flow limitations (flattening), for example in the flow contour of the inspiration. Flow limitation is a partial occlusion of the upper respiratory tract that at least partially restricts the flow of respiratory gas into the lungs. Other typical respiratory limitations include apneas, hypopneas, snoring, and obstructions. However, the respiratory limitations (events) identifiable by different methods are always treated in the same way by increasing the base pressure in response to the detection of an event in the same manner to safely overcome the respiratory restriction.

The object of the present invention is therefore to provide for each event a therapeutically effective, but also as comfortable as possible a pressure increase.

The object is achieved by a ventilator having a flow generator configured to deliver a breathing gas to a patient interface with a positive pressure; at least one sensor means arranged to provide a flow and / or pressure signal associated with the respiratory gas flow; and a controller configured to control the flow generator to generate a respiratory gas flow, wherein the controller provides a low base pressure of the respiratory gas, and wherein the controller is further configured to detect different events from the flow and / or pressure signal which may affect the patient's breathing gas supply, characterized in that the controller is configured to increase the base pressure in a first predetermined manner in response to the detection of at least one first event and the base pressure in a second predetermined response to the detection of at least a second event Increase way, which differs from the first way.

Surprisingly, it has been shown that a characteristic pressure reaction is optimal for the different respiratory restrictions (events).

In addition, it has been shown that certain patients benefit from a generally more dynamic pressure response to events.

The ventilator is advantageously characterized alternatively or additionally in that the first event and the second event are identical.

The ventilator is for example alternatively or additionally characterized in that the first event and the second event are different.

The ventilator is advantageously alternatively or additionally characterized in that the control device detects an obstruction of the respiratory tract from the flow and / or pressure signal as an event.

The ventilator is advantageously alternatively or additionally characterized in that the control device detects an apnea as an event from the flow and / or pressure signal.

The ventilator is advantageously alternatively or additionally characterized in that the control device detects a hypopnea as an event from the flow and / or pressure signal.

The ventilator is advantageously alternatively or additionally characterized in that the control device detects snoring from the flow and / or pressure signal as an event.

The ventilator is alternatively or additionally characterized in that the control device detects from the flow and / or pressure signal from the inspiratory section a flattening of the respiratory flow curve as an event flattening.

Alternatively or additionally, the ventilator may be characterized in that the control device recognizes snoring or flattening as the first event from the flow and / or pressure signal and then increases the base pressure in a first manner.

The ventilator is also alternatively or additionally characterized in that the pressure increase takes place at least in phases with at most 50 hPa / sec and the pressure level reached is at least in phases at most 2 hPa above the base pressure.

The ventilator is for example alternatively or additionally characterized in that the control device detects from the flow and / or pressure signal as a second event apnea or hypopnea and then increases the base pressure in a second manner, the pressure increase is more dynamic and the pressure level reached is higher as in the first way.

The ventilator also alternatively or additionally characterized in that the pressure increase takes place with at least 50 hPa / sec and the pressure level reached is at least 3 hPa above the base pressure.

The ventilator is also alternatively or additionally characterized in that the control means only increases the base pressure if at least four snoring events have been registered within a period of 2 minutes.

The ventilator is alternatively or additionally characterized in that the control device only increases the base pressure if at least six snoring events have been registered within a period of 2 min.

The ventilator is also alternatively or additionally characterized in that the control means only increases the base pressure if at least eight snoring events have been registered within a period of 2 minutes.

The ventilator is alternatively characterized in that the control device increases the base pressure only after a period of 2 minutes, if at least two events have been registered within the time span.

The ventilator is also characterized in that, upon user selection by the control means, pressure increase is controlled in a third manner which is performed more dynamically than in the first or second manner.

To change from the dynamic mode to the standard mode and vice versa, the user can also first select the desired mode via the control element. The control element can be designed as a control button, button, or surface in the area of the respirator and can function mechanically or optically or electronically or, alternatively, the user selection can be made by remote transmission.

1 shows the basic structure of a device for ventilation ( 1 ). In the area of a device housing with control panel ( 10 ) as well as display ( 11 ) is arranged in a device interior, a breathing gas pump. Via a coupling ( 14 ), a connection hose is connected. Along the connecting hose, an additional Druckmeßschlauch extend, which is connectable via a pressure input port to the device housing. To enable data transmission, the device housing has at least one interface ( 12 . 13 ) on.

In the area of the device housing is a control element ( 15 ) to manually specify a dynamic mode of the ventilator. The control element ( 15 ) can be arranged in the area of the control panel or be designed as an external or separate control.

To avoid dehydration of the respiratory tract, it proves to be particularly useful for longer periods of ventilation to carry out a humidification of the air. Such humidification of the breathing air can also be realized in other applications. For humidification, a humidifier is adapted laterally.

It is possible for the control device to be suitable and designed to monitor a flow signal and / or a pressure signal and to evaluate it using at least one algorithm in order to type an event. The flow signal and / or the pressure signal are provided by at least one sensor means associated with the control device. The sensor means is for detecting at least one flow characteristic and / or at least one printing property of the Airflow intended for ventilation. The evaluation of flow signals or pressure signals enables a reliable detection and typing of events of the respiration. Particularly preferably, the control device is also suitable and designed to register on the basis of the flow signal and / or the pressure signal at least one ventilation parameter, such. For example, the respiratory rate, the tidal volume, the minute ventilation, the inspiratory flow and / or the inspiratory pressure and / or the airway resistance. In addition, the control device may be suitable and designed to supply the flow generator with an oscillating control signal. The flow generator then generates a respiratory gas flow with a modulated pressure oscillation, which is preferably in the range 1-20 Hz, more preferably at 2-10 Hz, or even at 4 Hz and pressure stroke of 0.1-1 cm H2O, preferably 0.4 cm H ₂ O effected. This pressure stroke also induces an oscillating flow. The control device may be suitable and designed to output a corresponding indication to a user in the event of registered respiratory events. For example, the indication can be visually and / or acoustically displayed by means of a display device. The indication can also be output, for example, by means of an interface to at least one external data processing device. Such an indication is particularly advantageous because, knowing the events, the ventilation treatment can be adjusted accordingly. On the other hand, in the absence of the hint a corresponding success of the ventilation treatment can be determined. The ventilator can be adjusted dynamically and in particular according to the breathing phase of the user. For example, a respiratory phase change can be detected on the basis of the control device, so that a higher or lower pressure can be provided depending on the respiratory phase. For example, the ventilator may be configured as a CPAP or APAP device. The ventilator 1 can also be designed as a bilevel device. For example, the ventilator responds 1 to certain respiratory events, such. As snoring, Atemabflachungen and / or obstructive pressure peaks with appropriate settings of the ventilation parameters. With the ventilator shown here 1 events that occur during respiration or during ventilation are recognized and typed. For this purpose, the sensor means detects one or more ventilation parameters such as pressure and / or flow and / or ODS signal and supplies corresponding signals to the control device 7 , The control device 7 analyzes the signals using suitable algorithms so that characteristic signal curves can be identified and typed as an event. In this case, for example, a parameter extraction with respect to levels and amplitude values, time intervals, envelopes, zero crossings and slopes can be used. In an analysis with regard to time characteristics, for example, periodicities and frequencies are used in a parameter extraction. Obstructive apnea (oA) is detected when a greatly reduced flow volume is detected for at least two breaths and / or an ODS surge occurs.

For example, obstructive hypopnea (oH) is manifested by a reduced flow volume for two consecutive inspirations or by obstructive flattening (a typical flattening of the respiratory curve) of the flow signal.

Obstructive snoring (oS) is recognized by cumulative snoring over at least two consecutive inspirations associated with obstruction or flattening.

Obstructive flattening (oF) is detected by cumulative flattening via at least three inspirations, at least one increase in the inspiratory ODS signal.

An obstructive event (oE) is detected by a significant accumulated inspiratory increase in the ODS signal.

Snoring (S) is detected by cumulative snoring (at least 3 consecutive inspirations) without inspiratory ODS surge.

Non-specific flattening (uF) is detected by cumulative flattening (at least 3 inspirations).

A central apnea (zA) is detected by a greatly reduced flow volume for 10 seconds without ODS surge or flattening.

Central hypopnea (zH) is detected by a reduced flow volume (2 consecutive inspirations) without ODS surge

Leakage in the area of the patient interface or mouth and mask leakage is detected by the fact that the target pressure can not be reached and / or the leakage flow is greater than 0.6 l / sec.

The detected events can then be stored in the memory device and used for ventilation statistics. An advantage of the event recognition is that on the basis of the typed events, an adaptation of the ventilation can take place, for. B. an automatic pressure increase in an obstructive apnea. In addition, some diagnostics of certain respiratory disorders can be made. A special advantage of the ventilator shown here 1 is the controller 7 which continue the detected events analyzed and registered by a characteristic occurrence of events also a CheyneStokes breathing. Such an event analysis is exemplary in the 2 outlined.

The 2 shows four exemplary events 9A -D captured and typed during a period of time. The ventilator ( 1 ) with a flow generator ( 2 ) for delivering a breathing gas to a patient interface ( 3 ) is configured with a positive pressure; at least one sensor means ( 4 ), which is set up, a flow ( 5 ) and / or pressure signal ( 6 ), which is associated with the respiratory gas flow; and a control device ( 7 ), which is configured to control the flow generator ( 2 ) so as to generate a breathing gas flow, the controller having a low base pressure ( 8th ) of the respiratory gas, and wherein the control device ( 7 ) is further configured from the flow and / or pressure signal ( 5 / 6 ) different events ( 9a . 9b . 9c . 9d ...), which may affect the patient's breathing gas supply, characterized in that the control device is configured in response to the detection of at least one first event ( 9a . 9b . 9c . 9d ...) the base pressure in a first way ( 19a ) and in response to the detection of at least a second event ( 9a . 9b . 9c . 9d ...) the base pressure in a second way ( 19b ), which differs from the first one, detects a first event ( 9a . 9b . 9c . 9d ...) and a second event ( 9a . 9b . 9c . 9d ...) which may be identical or which may be different. The control device ( 7 ) determined from the flow and / or pressure signal ( 5 / 6 ) as events an obstruction ( 9a . 9b . 9c . 9d ...) of the respiratory tract or an apnea ( 9a . 9b . 9c . 9d ...) or a hypopnea ( 9a . 9b . 9c . 9d ...) or snoring or flattening. The control device ( 7 ) recognizes, for example, from the flow and / or pressure signal ( 5 / 6 ) snoring or flattening as the first event ( 9a . 9b . 9c . 9d ...) and then raises the base pressure in a first way ( 19b ) which differs from an increase in pressure which the control device ( 7 ) on detection of hypopnea or apnea. The control device ( 7 ) can, for example, from the flow and / or pressure signal ( 5 / 6 ) snoring or flattening as the first event ( 9a . 9b . 9c . 9d ...) and then the base pressure in a first way ( 19a ), when the standard mode is selected ( 15 ) has been. The control device ( 7 ) can, for example, from the flow and / or pressure signal ( 5 / 6 ) snoring or flattening as the first event ( 9a . 9b . 9c . 9d ...) and then the base pressure in a second way ( 19b ) when the dynamic mode is selected ( 15 ) has been. The pressure increase of the second way ( 19b ) and the first mode differ, for example, in pressure rise time and / or pressure rise rate and / or pressure rise profile and / or maximum pressure and / or pressure fall time and / or pressure drop rate and / or pressure drop profile and / or minimum pressure.

2 shows the pressure curve in adaptation to different events ( 9A -D) for the dynamic mode and the standard mode. To change from the dynamic mode to the standard mode and vice versa, the user must first select the desired mode via the control element ( 15 ). It can be seen that the initial pressure is kept close to the minimum pressure Pmin in order to influence the patient as little as possible in his normal breathing. After the event A (an obstructive apnea or hyponoe) is detected, an identical pressure adjustment takes place in the dynamic mode and in the standard mode. The pressure is initially left at the level of event A to be specifically adjusted when event B (flow limitations, flattening) occurs. Here it can be seen that the pressure adjustment in the dynamic mode (dashed line) is stronger, and the pressure increases dynamically, as in the standard mode, where a pressure adjustment is omitted. During a phase without events ( 9c ) the pressure level drops in standard mode and also in dynamic mode. If another event is detected, snore (here 9d ) it can be seen that the pressure adjustment in the dynamic mode (dashed line) is stronger, and the pressure increases dynamically, as in the standard mode, where a pressure adjustment to a level below the level of the dynamic mode. At event 9d striking that an immediate pressure reaction in dyn. Mode takes place while the rise in standard mode takes place later and gently.

3 shows how the use of forced oscillation technique (ODS) can differentiate between obstructive and central apneas. The control device can act on the flow generator with an oscillating control signal. The flow generator then generates a respiratory gas flow with a modulated pressure oscillation ( 3a ) Which is preferably in the range 1-20 Hz, more preferably 2-10 Hz, or at 4 Hz and the pressure stroke of 0.1-1 cm H2O preferred causes 0.4 cm H ₂ O. This pressure stroke also induces an oscillating flow ( 3b ). Based on the resulting air flow and pressure, resistance and obstruction in the upper respiratory tract are determined. In obstructive apnea (oA) 3c there is virtually no resulting flux to measure. In a central apnea (CA) 3b on the other hand, a resulting flow has to be measured.

Standard Mode

On apneas and hypopneas is reacted with a greater increase in pressure and a little less on flattening and snoring. The average pressures and leaks are kept as low as possible. Adaptation to a new print takes place within or after the end of an epoch of 1 to 2 minutes.

Dynamic mode

Upon user selection, a stronger and faster pressure response (than in standard mode) will result in snoring and flattening and even mild obstruction. Breathing becomes even more normalized. Optionally or additionally, the pressure drop rate is controlled so that the pressure drops more slowly than it has increased.

According to the invention, a pressure change takes place only at the end of the epoch. Obstructive hypopneas (oH) and obstructive apneas (oA) have an immediate response, up to 2x in the epoch.

Likewise with snoring of> 3 breaths in epoch or snoring> 6 breaths in the epoch. Snoring episodes are not recognized by the percentage (15% or 40%) of snore breaths within an epoch, but by absolute numbers. Advantage: To know the percentage, you have to wait until the epoch end. Whether a fixed number is reached, you know in between. Accordingly, the pressure can be raised earlier, this is done in dynamic mode or on selection.

Too rapid or severe lowering of the elevated pressure level leads to renewed obstruction. Therefore, according to the invention, the pressure drop rate is controlled accordingly.

According to the invention, a maximum pressure Pmax which is not exceeded can additionally be preset in each mode. In standard mode, but also in dynamic mode, the pressure adjustment takes place shortly before Pmax is reached with gradual or steadily decreasing slope.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0373585 [0003]
• EP 0705615 [0003]
• EP 1136094 [0003]
• DE 102007011924 [0003]

Claims (11)

Ventilator ( 1 ) with a flow generator ( 2 ) for delivering a breathing gas to a patient interface ( 3 ) is configured with a positive pressure; at least one sensor means ( 4 ), which is set up, a flow ( 5 ) and / or pressure signal ( 6 ), which is associated with the respiratory gas flow; and a control device ( 7 ), which is configured to control the flow generator ( 2 ) so as to generate a breathing gas flow, the controller having a low base pressure ( 8th ) of the respiratory gas, and wherein the control device ( 7 ) is further configured from the flow and / or pressure signal ( 5 / 6 ) different events ( 9a . 9b . 9c . 9d ...), which may affect the patient's breathing gas supply, characterized in that the control device is configured in response to the detection of at least one first event ( 9a . 9b . 9c . 9d ...) the base pressure in a first way ( 19a ) and in response to the detection of at least a second event ( 9a . 9b . 9c . 9d ...) the base pressure in a second way ( 19b ), which differs from the first one. Ventilator device according to claim 1, characterized in that the first event ( 9a . 9b . 9c . 9d ...) and the second event ( 9a . 9b . 9c . 9d ...) are identical. Ventilator device according to claim 1, characterized in that the first event ( 9a . 9b . 9c . 9d ...) and the second event ( 9a . 9b . 9c . 9d ...) are different. Breathing apparatus according to at least one of the preceding claims, characterized in that the control device ( 7 ) from the flow and / or pressure signal ( 5 / 6 ) as event an obstruction and / or an apnea and / or a hypopnea and / or snoring and / or from the inspiratory section a flattening of the respiratory flow curve as an event flattening ( 9a . 9b . 9c . 9d ...) of the respiratory tract is detected. Breathing apparatus according to at least one of the preceding claims, characterized in that the control device ( 7 ) from the flow and / or pressure signal ( 5 / 6 ) as the first snoring or flattening event ( 9a . 9b . 9c . 9d ...) and then the base pressure in a first way ( 19b ) elevated. Ventilator according to at least one of the preceding claims, characterized in that the pressure increase (in a first manner) at least in phases with at most 50 hPa / sec and the pressure level reached is at least in phases by at most 2 hPa above the base pressure. Breathing apparatus according to at least one of the preceding claims, characterized in that the control device ( 7 ) from the flow and / or pressure signal ( 5 / 6 ) as a second event an apnea or hypopnea ( 9a . 9b . 9c . 9d ...) and then the base pressure in a second way ( 19b ), wherein the pressure increase is more dynamic and the pressure level reached is higher than in the first way ( 19a ). Ventilator according to at least one of the preceding claims, characterized in that the pressure increase takes place with at least 50 hPa / sec and the pressure level reached is at least 3 hPa above the base pressure. Breathing apparatus according to at least one of the preceding claims, characterized in that the control device ( 7 ) increases the base pressure only when at least four snoring events have been registered within a period of 2 minutes. Breathing apparatus according to at least one of the preceding claims, characterized in that the control device ( 7 ) increases the base pressure only after a period of 2 minutes if at least two events have been registered within the time period. Breathing apparatus according to at least one of the preceding claims, characterized in that on user selection by the control device ( 7 ) a pressure increase in a third way ( 19c ) which is performed more dynamically than in the first or second way ( 19c ).

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