Device for ventilation

Abstract

Device for ventilation, comprising: a breathing gas source for providing breathing gas for the ventilation of a patient; at least one sensor connected to an interface (8) of the device, which can be positioned on the patient's skin and is designed to non-invasively measure at least one component of the patient's blood as at least one ventilator-dependent blood parameter; a control device designed to evaluate at least one blood parameter and autonomously change at least one operating parameter of the device depending on the at least one blood parameter, wherein maximum corridors are specified for the at least one operating parameter to prevent implausible automatic ventilation settings, and operator inputs are evaluated to take external control specifications into account; a device housing (1) with a control panel (2) and a display (3), wherein an oxygen supply valve is adaptable to the device in the area of ​​the device housing (1) and a respiratory gas pump is arranged in an interior of the device, wherein a humidifier is also adaptable to the device, wherein the display (3) is designed as a display so that a physician can select a disease pattern directly on the display; a modem or other interface for transmitting recorded data to the physician, as well as abnormalities, operating hours, or other data to a maintenance or customer service department to ensure proper functioning of the device; wherein the control device is designed to change the at least one operating parameter within a control loop, to which data of the at least one blood parameter are supplied as setpoint and actual values, and to assign strategies for carrying out the control to specific disease patterns, wherein each strategy includes a priority list of 1 to N different settings that are to be processed within the respective bandwidths when applying the strategy, wherein the strategies with their respective settings and bandwidths can be stored and made available as fixed predefined strategies for specific disease patterns; wherein the control device is further configured to take into account characteristic settings and their ranges for the disease pattern chosen by the physician and to apply the settings taken into account; wherein at least one blood parameter includes a carbon dioxide partial pressure and the control device is further designed to compare an actual value of the carbon dioxide partial pressure with a setpoint when performing the control and, if a current strategy has been fully executed and the setpoint has not been reached, to automatically apply a new strategy suitable for further improving the patient's condition.

Description

[0001] The invention relates to a device for ventilation which has a control unit, a respiratory gas source and at least one sensor for detecting a respiratory-dependent parameter.

[0002] Such devices are used, for example, to optimize the operation of ventilators. The aim of such optimization might be to minimize energy consumption, noise emissions, user comfort, or precise adherence to predefined ventilation parameters. Applications in the medical technology sector include BiLevel, PSV / PCV, VCV, and other forms and types of ventilation, as well as CPAP or APAP. Applications in the medical technology sector also include mobile and stationary oxygen or oxygen-enriched air supply for patients.

[0003] However, various applications are also possible outside the field of medical technology. For example, with ventilators for divers or firefighters, the problem may arise that energy consumption must be minimized when battery-powered, or that acoustic perception should be impaired by as little background noise as possible. The same problem can also occur in the industrial sector in activities that require the use of respiratory devices to protect the person from the effects of environmental gases, and in which the persons in question do not have their hands free to operate the ventilators themselves. Finally, applications for ventilators used by astronauts or pilots are also conceivable.

[0004] In patients with respiratory insufficiency, the key parameter for setting the ventilation rate is the partial pressure of carbon dioxide, PaCO2. The goal of ventilation is to ventilate the patient into the normocapnic range, i.e., to ensure, for example, the ability to exhale CO2 with the help of the ventilator. Normocapnia is generally defined as a PaCO2 of 40 mmHg (pCO2 <45 mmHg).

[0005] According to current best practices, an invasive blood gas analysis is performed during patient titration for ventilation to determine PaCO2. For this purpose, a blood sample is taken before and after ventilation, and the blood values ​​SaO2, PaO2, PaCO2, pH, base excess (BE) concentration, temperature, metabolites, and electrolytes are determined.

[0006] This method has several disadvantages: • Invasiveness and thus causing pain to the patient, • Snapshot of blood gas values, • Workload in terms of personnel and time, • Restricted to clinical use, • Cost factor of the analysis (centrifuge equipment, etc.).

[0007] German patent DE 196 50 738 A1 discloses a device for volume control in cases of blood loss. This involves a computer connected to several sensor units that non-invasively determine at least one parameter of the user's blood.

[0008] German patent DE 692 14 730 T2 relates to a device for monitoring the activity of a patient's respiratory muscles. The necessary parameters are derived from the respiratory gas signals of pressure and flow. Information about respiratory muscle activity can be used to adjust ventilation parameters.

[0009] German patent DE 360 4 986 A1 discloses a device for monitoring respiration and oxygenation during sleep. The device uses sensors to determine physiological parameters related to the patient's respiration or oxygenation. Upon detection of insufficient oxygenation, a respiratory arousal stimulus is generated.

[0010] US patent 4,875,477 A discloses a face mask with integrated sensors that can be used to determine vital signs. The sensors are located within the mask and are in contact with the user's face.

[0011] EP 1 148 907 B1 and US 2002 / 0110849 A1 propose a method for determining alveolar opening and closing of the lungs. This determination can be performed non-invasively using SpO2 or end-tidal CO2 concentration. The ventilation parameters are then controlled, taking alveolar opening and closing into account, to achieve maximum gas exchange in the lungs.

[0012] US Patent 5,103,814 A discloses a method and a device for weaning a patient from mechanical ventilation. In this process, the ventilator non-invasively determines the oxygen saturation as a parameter of the user's blood and adjusts the oxygen supply in the breathing gas and the ventilation rate accordingly.

[0013] The object of the present invention is to improve a device of the type mentioned in the introduction in such a way that safe, automated ventilation is possible and the need for specialist personnel can be largely dispensed with.

[0014] This problem is solved according to the invention by the features of the main claim.

[0015] This problem is also solved according to the invention by determining at least one parameter of the user's blood non-invasively as a respiratory-dependent parameter.

[0016] In one implementation variant, this parameter is determined by a sensor positioned on the user's skin.

[0017] In another implementation variant, this parameter is determined by a sensor for analyzing the exhaled air.

[0018] In this context, blood components can also be considered blood parameters.

[0019] In particular, consideration has also been given to the fact that, as a respiratory-dependent parameter, at least one component of the user's blood is measured non-invasively by at least one sensor positioned on the skin of a patient.

[0020] A further object of the present invention is to construct a device of the type mentioned in the introduction in such a way that, with high functionality, simple usability with just a few steps is supported.

[0021] This problem is solved according to the invention by the sensor being designed for placement on the skin of a user and for non-invasive measurement of at least one parameter of the user's blood.

[0022] Non-invasive determination of blood parameters during ventilation allows for rapid trend values ​​to be obtained for analyzing the effectiveness of the ventilator settings and avoids the disadvantages of conventional blood gas analysis.

[0023] By non-invasively determining blood values, especially the CO2 value, and transmitting this information to the control system of the connected ventilator, the ventilation parameters are automatically adjusted by the ventilator to achieve a predetermined target carbon dioxide partial pressure.

[0024] Within a predefined range of minimum and maximum limits for ventilation settings (safety function), a ventilator is granted full or limited autonomy to achieve the predefined blood gas target values. The ventilation setting under which the target value was reached is maintained by the device as long as the target CO2 remains within a tolerance range.

[0025] To prevent implausible automatic ventilation settings (e.g., hyperventilation, hypoventilation, baro- / volutrauma, etc.), maximum ranges are predefined for the parameters (f, Ti:T, IPAP, EPAP, Vt, etc.). These can also be monitored via alarms.

[0026] If the target CO2 value is exceeded, the ventilator automatically adjusts the settings as needed within the permitted ranges. This can be relevant, for example, when changing position, during different sleep stages, or when lung impedance changes, etc.

[0027] By using the device according to the invention, it is possible to ventilate the patient into the normocapnic range, which is a PaCO2 of 40 mmHg (pCO2 <45 mmHg). This value is the target for every patient, but cannot be achieved in every patient, as many patients become accustomed to hypercapnia, which may have been present for a long time. For this reason, the target CO2 value can also be set and readjusted by the physician.

[0028] One embodiment of the device according to the invention thus features a ventilation autotitration with predefined target parameter CO2. For example, patients with hypercapnia (>50 mmHg at rest) and mild COPD are ventilated with the following parameters: Volume specification: 900±100ml Respiratory rate: 20±3 breaths / min Ventilation pressure: 25±9 mbar

[0029] This is primarily used to configure a patient requiring long-term ventilation, thereby relieving the physician by partially or completely transferring the patient to the ventilator and thus saving costs. The device can be started with preset settings from the physician, and after a certain recording period and automatic adjustment of the settings by the ventilator, the patient can then take these settings home and use them in their home environment.

[0030] To better respond to gradual changes in the patient's condition that require device adjustments, a measuring device for determining their pCO2 level is attached not only under the doctor's supervision but also during home ventilation. This can be done, for example, on the ear, finger, or any other location on the body. Communication between the measuring device and the machine can be established via various methods: wired connection, radio, infrared, or Bluetooth. ® , mechanical, electrical, etc.

[0031] The device records changes and issues a warning message in the event of critical changes in the lung or patient's condition, advising the patient to contact their physician. Alternatively, for certain patients, the physician can authorize automatic adjustment of the ventilator parameters. In another embodiment of the invention, the notification to the physician can also be sent directly via an interface (telephone system, mobile phone, and other data transmission options, etc.).

[0032] For certain disease patterns, the preset settings present at system startup are replaced, for example, by fixed settings stored in the fan. This allows the doctor to select the disease pattern directly on the display, and the device takes into account important settings and their ranges characteristic of that disease, and adjusts the relevant settings accordingly.

[0033] In addition to pCO2 measurement, non-invasive measurement of oxygen content and resulting optional oxygen administration can also be used to improve the patient's condition, for example continuously, as a demand system using bolus administration or other application methods and forms.

[0034] Surprisingly, in test series conducted to test the invention, a significant reduction of pCO2 to the range of normocapnia (pCO2 <45 mmHg) was observed in 18 out of 20 patients.

[0035] Since transcutaneous CO2 measurement is now technically mature and available, and the measured values ​​are close to the Pa-CO2 values, the invention proposes the use of the technology, for example, from SENTEC (SenTec AG, Ringstrasse 39, 4106 Therwil, CH) (V-Sign system), for implementation in ventilators. This technology is described, for example, in EP 1335666 and EP 1535055.

[0036] The SENTEC sensor system allows for the application of the measuring probe to the ear of adult patients over extended periods with sufficient accuracy in monitoring PtcCO2 trends, while simultaneously maintaining low operating costs. This technology offers significant advantages over the previously established measurement technology from Radiometer using diffusion electrodes, such as no electrode wear / oxidation, low drift, and straightforward / automatic system calibration. One embodiment of the invention envisions integrating an OEM solution of the SENTEC sensor system with a ventilator.

[0037] Measurement technology, including sensors, ear clips, and a membrane exchange function for calibration, should be integrated. All monitoring functions, capnography parameter / alarm threshold settings, and the software itself are implemented in the ventilator. For example, the power supply and control of the CO2 monitoring system are integrated / linked to the ventilator's firmware.

[0038] The invention can also be implemented as a modular design. The basic unit, a prior art fan, is mechanically and electrically connected to an optional component. In this case, the fan detects that this module is connected and automatically switches to the required mode.

[0039] Besides SENTEC, Kontron (Kontron AG, Oskar-von-Miller-Straße 1, 85386 Eching / Munich, Germany) offers comparable OEM solutions that can be integrated into / on ventilators. Tosca also has established sensors that can be used for this purpose.

[0040] Additionally, Linde Medical Sensors AG offers a sensor that functions as follows: Oxygen and carbon dioxide can diffuse through human skin. A heated sensor, approximately 43 to 44°C, is used. Due to increased blood flow, especially in the upper layers of the skin, and perspiration as a natural reaction to the warming, diffusion of gases—in this case, O2 and CO2—between the skin and the skin surface is facilitated, and the gases thus reach the sensor surface. According to the invention, other technologies for the non-invasive measurement of PaCO2 can also be linked / coupled with ventilators to enable the control of the ventilator to a target PaCO2 level based on PaCO2 measurement.

[0041] According to the invention, it is also intended to determine the CO2 content of the exhaled air and to use it as an indirect method for determining PaCO2 for control purposes. For example, end-tidal spectroscopic CO2 measurement is suitable.

[0042] Furthermore, the device is designed to utilize both technologies – measuring the CO2 content of exhaled air and transcutaneous measuring the pCO2 content – ​​to detect pathological changes in lung tissue (e.g., incipient pulmonary edema, mucus buildup, etc.) by comparing the two measurements. For example, a high pCO2 and a low spCO2 can indicate impaired gas exchange in the lungs.

[0043] According to the invention, it is also intended to determine other blood values ​​such as SaCO, SaO2, pH value, bicarbonate (HCO3) concentration, base excess (BE) and hemoglobin concentration non-invasively and to use the values ​​to control a ventilator.

[0044] The concentration of the ingredient can be measured, for example, by measuring a proportion of the parameter in the blood.

[0045] To determine a particularly ventilation-sensitive parameter, it is proposed that the level of carbon dioxide in the blood be measured.

[0046] Precise adherence to target values ​​can be achieved by making changes to the operating parameter of the ventilator within a control loop, to which data on the blood parameter are supplied as target and actual values.

[0047] A further improved control concept can be achieved by adapting the control strategy based on the measurement results and the ventilation mode. Naming and / or assigning strategies to specific disease patterns can also be considered particularly advantageous. This allows the device to provide pre-programmed strategies with their settings and bandwidths for specific disease patterns and to respond optimally to them. These specific strategies are predefined by the device. In addition, there are user-defined strategies that the physician can configure, name, and save according to their needs.

[0048] Further increase in adaptability can be achieved by selecting a mode when changing the operating parameter.

[0049] Operator-independent operation is supported by the fact that the change of the operating parameter is carried out autonomously by the control unit.

[0050] To take external control requirements into account, it is proposed that operator inputs be evaluated by the control unit.

[0051] Accurate adherence to target values ​​is supported by the continuous evaluation of sensor measurement information by the control unit.

[0052] The required evaluation effort can be reduced by having the control unit evaluate measurement information from the sensor only within predefined time periods.

[0053] A large degree of freedom in choosing a suitable location for the sensor can be achieved by placing the sensor within the area of ​​a pavement.

[0054] Rapid positioning of the sensor is facilitated by its placement within a clip.

[0055] Very simple usage processes are supported by the fact that the clip can be positioned within the area of ​​a user's finger.

[0056] Especially for mobile applications, it proves advantageous that the clip can be positioned in the area of ​​one of the user's ears.

[0057] The sensor can be applied to any well-vascularized area of ​​the body. Particularly suitable locations include the earlobes, fingertips, temples, forehead, and the area around the nose. To significantly improve usability and comfort, a transcutaneous sensor can be integrated into the forehead support of a mask used for respiratory and sleep therapy.

[0058] Another preferred position is the temples, where either the forehead support or the bandages can be used to fix the entire mask. The sensor can be positioned on two axes (x,y). Integration of the sensor into the mask's rim is also possible.

[0059] Since the sensor is attached to the mask or its straps, this arrangement allows the electrical connection between the sensor and the device to be positioned close to the breathing tube. The sensor's cable connection could optionally be embedded within the tube or attached to the outside of the tube, so that, for example, only the breathing tube with integrated connections for measurement and control channels needs to be secured to the mask with a single plug connection. Integrating a wireless transmission unit into the sensor allows the acquired data to be transmitted in compressed form to the evaluation unit within the device and incorporated into the control and regulation processes.

[0060] Another suggestion is to integrate medication administration via the endotracheal tube by recording the PaCO2 signal in the established pattern. This allows for targeted responses to specific physiological conditions of the patient. Medication can be administered using a humidifier or nebulizer, among other methods.

[0061] The drawings illustrate exemplary embodiments of the invention. They show: Fig. 1 A perspective view of a ventilation device with basic unit, breathing gas hose and breathing mask, Fig. 2. A schematic block diagram to illustrate the implementation of the control procedure. Fig. 3. A detailed block diagram for implementing device control with automatic or selectable adjustment of the operating mode and control strategy. Fig. 4. A detailed block diagram for further documentation of the functional blocks "Strategy User" in Fig. 3, Fig. 5 a block diagram accordingly Fig. 4 in an automatic strategy application, Fig. 6 a sensor positioned at the user's ear, Fig. 7 a sensor located on a user's finger, Fig. 8 a display indicator, Fig. 9 a user with a breathing mask on and Fig. 10 a ventilation mask with marked areas for attaching a sensor.

[0062] Fig. Figure 1 shows the basic structure of a ventilation device. A breathing gas pump is located inside a device housing (1) with a control panel (2) and display (3). A connecting hose (5) is attached via a coupling (4). An additional pressure measuring hose (6) can run along the connecting hose (5) and can be connected to the device housing (1) via a pressure inlet port (7). The device housing (1) has an interface (8) to enable data transmission. A humidifier can be attached.

[0063] An exhalation element (9) is arranged in the area of ​​an extension of the connecting hose (5) facing away from the device housing (1). An exhalation valve can also be used.

[0064] Fig. Figure 1 further shows a patient interface designed as a ventilation mask (10), which is implemented as a nasal mask. It can be secured to the patient's head using a head cap (11). The patient interface (10) has a coupling element (12) in the area of ​​its extension facing the connecting tube (5).

[0065] The blood glucose sensor can be connected to the ventilator via interface (8). The interfaces can be wired, infrared, Bluetooth, or USB. In particular, the connection between the blood glucose sensor and the ventilator can be electrical, pneumatic, optical, mechanical, or a combination of these. An oxygen inlet valve can be adapted to the ventilator within the device housing. It is conceivable to enrich the breathing gas with oxygen to improve patient care.

[0066] In addition, one of the devices can be equipped with interfaces to third-party devices and information management systems, for example for the inclusion of storage media, for connection to an ECG, EEG, printer, defibrillator, etc.

[0067] Recorded data, such as trends, extraordinary events, warnings, etc., can also be transmitted to the doctor via a modem or other interface, as well as anomalies, operating hours, or other information to ensure proper functioning to the maintenance / customer service department as needed.

[0068] The invention also intends to apply the described methods and means to the field of emergency medicine. While capnometry is already used in this area according to the prior art, there is currently no communication between the capnometry system and the emergency ventilator. To ensure this in the future, particularly during patient transfers, ventilation at a target value is also being pursued in this sector. Here, the mature technology of pulse oximetry, even in combination with capnography, is applicable and advantageous. With the "Air-Mix" setting, the ratio of oxygen to ambient air in an emergency / transport ventilator can be adjusted to conserve oxygen, which is typically only available in limited quantities in a pressurized gas cylinder.

[0069] To achieve the desired oxygen-saving effect, oxygen supply could be controlled and applied either generally or during the initial inhalation phase, depending on oxygen saturation. This, combined with monitoring SaO2 and calculating the difference between SaO2 and target SaO2, enables dependent oxygen delivery.

[0070] According to another embodiment, a full-face mask or an endotracheal tube can also be used. The interface (13) is provided for connection to the sensor, which is intended for measuring PCO2, SpO2 and pulse rate or other blood gas values.

[0071] The procedure will be carried out in Fig. 3. This is explained by way of example. When titrating a patient to a ventilator with ventilation to a target value, the patient's blood is either subjected to a blood gas analysis or the PaCO2 value is determined using the possibilities and methods already explained and listed.

[0072] From the outside, it is now possible to directly input a disease pattern, whereby the device is granted almost complete autonomy over the following decision-making options, depending on the level of autonomy. The data required for device autonomy, such as settings, bandwidths, minimums, and maximums, are stored in the device and read out as needed. The device then prompts a decision regarding the ventilation method (pressure / volume-controlled ventilation). Subsequently, the target CO2 value can be queried.

[0073] The next step involves determining whether the patient should receive assisted, controlled, or assisted / controlled ventilation. Depending on the patient's level of autonomy, the system can then decide externally or automatically which parameters, and within what ranges (maximum and minimum values), of the ventilation parameters should be set, or whether a list of strategies should be used. Each of these strategies contains a priority list of 1 to N different settings and is processed within its specified range.

[0074] For example, the current PaCO2 value can be queried and compared to the target CO2 value, allowing a decision to be made regarding further processing of the prioritized bandwidth. If the change in a bandwidth is exhausted, the next parameter in the strategy is adjusted until the target CO2 value is optimally set for the patient. If a strategy has been fully executed and the target CO2 value has not been reached, a new strategy, a new target CO2 value, a new ventilation method / control parameters (pressure / volume controlled), or a new mode (assisted and / or controlled ventilation) could be implemented to further improve the patient's condition. This decision can be communicated to the user via an alarm and / or prompted by the device itself, or it can be made automatically by the device.

[0075] Alternatively, the target value can be defined as a range, so that the device has a goal to achieve. However, if all available strategies have been exhausted, the currently achieved settings can also be accepted by the device. The target value and the target value range can be configured in the device settings.

[0076] To achieve high setting accuracy and speed, the change intensity a and the cycle time T_z are calculated, queried program-specifically, or read from internal memory. The change intensity a determines the magnitude of the change in the current parameter, while the cycle time determines the duration until the respective parameter is changed again, as described in Fig. 4 and Fig. Figure 5 illustrates this. This addresses the fact that the CO2 level takes a certain amount of time to stabilize and that each patient reacts differently to changes in ventilation parameters. Both values ​​are therefore calculated from patient- and device-related data. The intensity of the change can depend, for example, on the cycle time and the difference between the PaCO2 value and the target CO2 value, as well as other parameters derived from ventilation-relevant times, and vice versa.

[0077] Furthermore, it is possible to differentiate the intensity of change and subject it to a threshold system. Depending on which threshold(s) are exceeded, the intensity of change is adjusted.

[0078] To perform more efficient titration, the technology of self-learning machines (artificial intelligence, neural networks) can also be used. The continuously collected and evaluated data allows for better parameter adjustments and leads to faster titration of patients with specific disease patterns. This can be done either for each individual device or centrally collected via interfaces and transferred to the other devices.

[0079] It is generally known that the CO2 value can be improved mainly through pressure, so this is also the method of choice for the above proposal, and the other settings are based on this or take a back seat.

[0080] This intelligent ventilation method enables, for the first time, a link between blood values ​​and the corresponding ventilation settings. This translates into a significant improvement in the time, cost, and quality of ventilation settings and monitoring.

[0081] Further examples are described in Fig. 6 and Fig. Figure 7 shows the sensor can be attached either to the patient's ear or fingertip. Furthermore, the ventilator can be adjusted according to... Fig. 8. It must be equipped with a monitor displaying the current settings and patient data determined by the device as a value or in curve form. Fig. Figure 9 illustrates the use of the breathing mask by a patient.

[0082] Another embodiment for mounting a sensor close to the skin is shown in Fig. Figure 10 shows all the areas where, for example, a sensor can be placed.

Claims

[1] A device for ventilation comprising: a breathing gas source for providing breathing gas for the ventilation of a patient; at least one sensor connected to an interface (8) of the device, which can be positioned on the patient's skin and is designed to non-invasively measure at least one component of the patient's blood as at least one ventilator-dependent blood parameter; a control device designed to evaluate at least one blood parameter and autonomously change at least one operating parameter of the device depending on the at least one blood parameter, wherein maximum corridors are specified for the at least one operating parameter to prevent implausible automatic ventilation settings, and operator inputs are evaluated to take external control specifications into account; a device housing (1) with a control panel (2) and a display (3), wherein an oxygen supply valve is adaptable to the device in the area of ​​the device housing (1) and a respiratory gas pump is arranged in an interior of the device, wherein a humidifier is also adaptable to the device, wherein the display (3) is designed as a display so that a physician can select a disease pattern directly on the display; a modem or other interface for transmitting recorded data to the physician, as well as abnormalities, operating hours, or other data to a maintenance or customer service department to ensure proper functioning of the device; wherein the control device is designed to change the at least one operating parameter within a control loop, to which data of the at least one blood parameter are supplied as setpoint and actual values, and to assign strategies for carrying out the control to specific disease patterns, wherein each strategy includes a priority list of 1 to N different settings that are to be processed within the respective bandwidths when applying the strategy, wherein the strategies with their respective settings and bandwidths can be stored and made available as fixed predefined strategies for specific disease patterns; wherein the control device is further configured to take into account characteristic settings and their ranges for the disease pattern chosen by the physician and to apply the settings taken into account; wherein at least one blood parameter includes a carbon dioxide partial pressure and the control device is further designed to compare an actual value of the carbon dioxide partial pressure with a setpoint when performing the control and, if a current strategy has been fully executed and the setpoint has not been reached, to automatically apply a new strategy suitable for further improving the patient's condition. [2] Device according to claim 1, wherein the sensor is configured to measure the concentration of carbon dioxide in the blood as the at least one ingredient. [3] Device according to claim 1 or 2, wherein the sensor is configured to measure the oxygen content in the blood as the at least one ingredient. [4] Device according to one of the preceding claims, wherein the sensor can be arranged in the area of ​​a pavement. [5] Device according to one of the preceding claims, wherein the sensor can be arranged in the area of ​​a mask rim of a breathing mask. [6] Device according to one of the preceding claims, wherein the sensor can be arranged in the area of ​​a mask strap of a breathing mask. [7] Device according to one of the preceding claims, wherein the control device is configured to perform a strategy adaptation depending on the measurement result in order to carry out the control. [8] Device according to one of the preceding claims, wherein the control device is configured to perform a mode selection when the at least one operating parameter is changed. [9] Device according to one of the preceding claims, wherein the control device is designed to evaluate measurement information from the sensor only within predefinable time periods.

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