WO2000066207A1

WO2000066207A1 - Device for supplying a breathing gas under overpressure and a control unit for controlling the same

Info

Publication number: WO2000066207A1
Application number: PCT/EP2000/003998
Authority: WO
Inventors: Harald Genger; Claus Negele
Original assignee: MAP Medizintechnik für Arzt und Patient GmbH & Co. KG
Priority date: 1999-05-04
Filing date: 2000-05-04
Publication date: 2000-11-09
Also published as: FR2793145A1; DE10021783B4; AU4561400A; DE10021783A1; FR2793145B1

Abstract

The invention relates to a device for supplying a breathing gas placed under overpressure and to a control unit for controlling the same. The inventive device comprises a blower for delivering the breathing gas, a breathing gas line for supplying the breathing gas from the blower to a breathing mask, and a first unit for generating signals which are representative of the flow of breathing gas or which change with the flow of breathing gas. The inventive device also comprises a second unit for generating signals which are indicative of the pressure of the breathing gas and comprises a control unit for controlling the blower on the basis of both the signals which are indicative of the flow of breathing gas as well as the signals which are indicative of the pressure of the breathing gas. According to a particularly preferred embodiment of the invention, the respiration pressure is adjusted according to the cerebral activity of the person receiving artificial respiration.

Description

1

Device for supplying a breathing gas under positive pressure and control arrangement for controlling the same

The invention relates to a device for supplying a breathing gas to a patient under excess pressure, and to a control arrangement for controlling such a device.

Devices of the type mentioned above are used in particular in the therapy of sleep-related breathing disorders. In contrast to the respirators that are generally only used for a short time, for example for supplying an anesthetic gas in the hospital, in particular in the operating theater area, the aim in sleep therapy ventilators is to deliver the respiratory gas to the patient in a manner which is perceived by the patient as pleasant, not only when awake, but is also particularly advantageous from a physiological point of view when sleeping.

Among the long-term use d h, among the sleep therapy ventilators intended for use over many years, there are devices through which the breathing gas, for example ambient air, is supplied to a spontaneously breathing patient with a predetermined ventilation pressure via a ventilation hose of a breathing mask. As an alternative to this, devices are also used in which the ventilation pressure is reduced during an expiration phase of the patient and is increased to a predetermined pressure level during a cyclically following inspiration phase

In the case of ventilators, the ventilator pressure is usually regulated via a control device. For this purpose, as is known, for example, from DE 37 32 475 AI or FR 2 663 547, the ventilator pressure generated by the ventilator can be measured through a control tube which is brought up to the patient such control tubes are usually inserted into the ventilation tube and open directly into the Breathing mask

In the case of such devices, a breathing gas outlet opening is formed in the area of the breathing mask, through which a predetermined gas flow can flow off both during the inspiration phase and during the expiration phase. In this way, with constant supply of breathing gas, a sufficient exchange of the breathing gas in the breathing tube is achieved (Co ₂ leaching) Depending on the design of the breathing gas outlet opening, there is a corresponding intensive purging of the breathing gas exhaled into the breathing tube during the expiration phase

In the treatment of sleep-related breathing disorders, it has proven to be advantageous to humidify the fresh gas supplied via the respirator. For this purpose, the sucked-in fresh gas can be passed over a water bath arranged downstream of a delivery device, for example a blower device U considerable condensate entry into both the ventilation hose and the control hose, which impairs the control of the pressure in the breathing mask and increases the flow resistance of the breathing hose

Instead of the control hose, it is possible, as suggested for example in EP 0 288 903 A2, to attach an electronic pressure transducer directly to the breathing mask and to pass the detected pressure via a measuring line to the control arrangement usually integrated in a CPAP device. However, this measuring arrangement is comparative expensive and expensive to maintain

The invention has for its object to provide a respirator intended for the therapy of sleep-related breathing disorders, which is characterized by a high level of functional reliability and an improved physiological tolerance with regard to the breathing gas change

With regard to the device for supplying the breathing gas, this object is achieved according to the invention by a device with the features specified in claim 1 This advantageously makes it possible to set the ventilation pressure in a comparatively small tolerance range with high dynamics in accordance with a predetermined setpoint value. The control tube previously inserted into the ventilation tube and guided into the area of the mask can preferably be completely dispensed with The cross-sectional area of the ventilation tube and a reduction in the tube surfaces coming into contact with the exhaled breathing gas in the mask-side end of the ventilation tube are reached. The ventilation tube can be cleaned in a comparatively simple manner. Furthermore, there is a considerably smaller problem that the control tube required up to now has become during a longer sleep phase of the patient closes By reducing the flow resistance of the ventilation hose due to the larger and more technically more favorable flow cross A better exhalation characteristic is also achieved in the sectional area, since the breathing gas can be returned to the breathing tube with less respiratory resistance during exhalation

The device according to the invention comprises a blower device, preferably formed by a motor and an impeller coupled thereto, for requesting the breathing gas, and a control arrangement, formed by an electronic and preferably programmable circuit, for controlling the demand for the breathing gas, in particular for controlling the speed of the motor of the blower device

According to a particularly preferred embodiment of the invention, a humidification device is provided downstream of the blower device, through which the breathing gas can be loaded with water and any desired active ingredients

The breathing gas is demanded from the breathing mask using a flexible ventilation hose line which, according to a particularly preferred embodiment of the invention, is constructed in several parts

A device for draining any condensate that may form in the ventilation hose line is advantageously provided in this ventilation hose line. seen This binary can be formed by a diaphragm, for example, from a porous material or also by at least one smaller bore. The device according to the invention comprises a pressure detection device for generating a pressure signal for the control arrangement, the pressure detection device detecting the pressure in the area of the ventilation hose at a measuring point, which is spaced upstream from a hose end on the mask side.This advantageously makes it possible to generate a uniform pressure signal which is largely free of unrepresentative harmonics.Thanks to the preferably larger distance of the measuring point from the breathing mask, there is also to a considerably lesser extent the problem that the measured value acquisition by Condensate or ejection is impaired

According to a particularly preferred embodiment of the invention, a compensating distance extends between the measuring point and the mask-side hose end, the length of which corresponds at least to 9 times the inner diameter of the ventilation hose. As a result, a sufficiently uniform measured value acquisition is achieved by means of the compensating space upstream of the breathing mask Compensating distance can be increased for people with a large lung volume or tendency to expectoration. Especially when breathing heavily humidified gas or to further reduce breathing resistance, it is possible to place the measuring point directly in the initial area of the ventilation hose line or in the CPAP device in front of the hose connection area preferably to be arranged after (downstream) a dampening device, if provided

The measuring point is advantageously arranged downstream of a humidification zone formed in the humidifying device.This makes it possible to largely compensate for any interference caused by the humidifying device.For example, the measuring point can be arranged in a connecting elbow or a cover element of a humidifying container. The measuring point is advantageously chosen such that only the static pressure is measured at this point. By additionally recording the absolute pressure or the dynamic pressure, it is possible to additionally record the instantaneous volume flow. It is also possible to determine the instantaneous volume flow based on the power supplied by the blower device or the speed of the blower device Consideration to determine the blower device characteristic

The measuring point is advantageously determined by the location of the mouth of a measuring line flowing into the breathing hose line. The measuring point is preferably arranged in a breathing gas line section extending between the breathing hose line and the humidification zone

A particularly inexpensive embodiment of the invention is provided in that the measuring point is located inside the ventilation hose line

An embodiment of the invention which is advantageous with regard to a particularly precise control of the breathing gas supply is provided in that the control arrangement comprises a computing device which determines the transmission behavior of the section of the ventilation hose line between the measuring point and the mask-side end of the hose line depending on the current breathing gas flow or one for the Blower motor speed or the motor power reference indicative measured value taken into account The transmission behavior of the ventilation hose line can be stored on a memory element by means of a map or a function defined, for example, by several support points

The measuring line is advantageously formed by a hose guided within the ventilation hose line, the length of which within the ventilation hose line is shorter by more than 9 times the inner diameter of the ventilation hose line than the ventilation hose line.This ensures that the measuring point is sufficiently far from the Mask is spaced The distance between the measuring point and the breathing mask proposed according to the invention can be achieved by retrofitting by inserting an intermediate element between the breathing mask and the ventilation hose line. Such an intermediate element can be cleaned in a simple manner

An embodiment of the invention which is advantageous with regard to particularly economical handling and maintenance of the device according to the invention is provided in that the measuring line is coupled to a sleeve element which is connected to a device soapy end section of the ventilation hose line can be connected. In an advantageous manner, the measuring hose line can also be pulled out of the ventilation hose line by pulling off the sleeve element. The production line can be led out of the breathing gas supply path in a manner that is economical in terms of production and maintenance

With regard to a control arrangement for controlling the supply of a breathing gas to a breathing mask, the object stated at the outset of the invention is achieved according to the invention by the steps of requesting the breathing gas by means of a blower device passing the breathing gas through a breathing hose line to a breathing mask, measuring the pressure at a measuring point upstream of the Respiratory mask located downstream of the humidifier and spaced from the mask end of the vent tube by more than 9 times the inside diameter of the vent tubing and adjusting the speed or delivery rate of the blower motor based on the sensed pressure causes it to be released As described above for the device according to the invention, it is possible to achieve a more favorable ventilation characteristic for the patient to be ventilated

In particular in combination with the specified measures, but also independently of this, it is advantageously possible according to a further solution concept of the invention to supply a breathing gas to a breathing mask by means of a blower device connected via a breathing gas line device, the current breathing gas flow being determined and on the basis the instantaneous respiratory gas flow, the pressure drop occurring along the respiratory gas conduit device between the blower device and the respiratory mask is calculated and the speed or the delivery rate of the blower device is adjusted taking into account the occurring pressure drop such that the pressure inside the respiratory mask reaches a predetermined desired pressure level.

The setpoint pressure level is advantageously not static but alternates during a breathing cycle according to a preselected time course. According to a particularly preferred embodiment of the invention, the course of the setpoint pressure level is particularly based on the physiological instantaneous state the sleeping state and body position, matched to a breathing person.

A particularly advantageous adjustment of the time course of the ventilation pressure for supplying a breathing gas to a breathing mask by means of a blower device connected via a breathing gas line device can also be achieved by coordinating the time course of the desired pressure level with the current brain activity of the breathing person.

For this purpose, according to a particularly preferred embodiment of the invention, it is possible to provide means by which the course over time of the desired pressure level is determined in accordance with the sleep profile determined.

Brain activity can preferably be detected by means, in particular electrodes, attached to the body, in particular to the head of the breathing person.

A particularly favorable and also advantageous embodiment of the invention for use in the home is given in that the brain activity is recorded using an electrode attached to the forehead of the breathing person. Such an electrode can be attached in a simple manner, for example in the form of an adhesive strip.

According to a preferred embodiment of the invention, the control arrangement for controlling the blower device speed is designed in such a way that it determines, on the basis of the signals indicative of the respiratory gas flow, a pressure drop arising between the pressure signal tap and the respiratory mask-side end of the ventilation hose. The direction of this pressure drop depends on the current flow direction of the breathing gas in the breathing tube.

In a particularly advantageous manner, the control arrangement is designed in such a way that it adjusts the respiratory pressure provided by the respiratory gas delivery device as part of an injection process to a higher pressure level corresponding to the expected pressure drop. For an expiration process, the control arrangement sets the respiratory gas pressure generated by the delivery device to a correspondingly reduced pressure level. In a particularly preferred embodiment of the invention, the device for generating the signals indicative of the respiratory gas flow is arranged in the area of the blower device, preferably integrated in the CPAP device Measurement signals obtained in this way can be favorably routed directly into a circuit provided on a corresponding control board

A particularly reliable embodiment of the invention, which is advantageous with regard to the precise detection of the current respiratory gas flow, is provided in that the device for generating the signals indicative of the respiratory gas flow is designed as a dynamic pressure detection device. This dynamic pressure detection device preferably includes a preferred embodiment of the invention, the first, the breathing gas demand direction (direction back pressure tap opening directed from the CPAP device to the mask) and a second back pressure tap opening pointing in the direction of breathing gas demand. The signals indicative of the breathing gas flow can preferably be determined by a differential pressure measurement between the pressures prevailing in the area of the respective back pressure tap openings. However, the two back pressure tapes are a particularly preferred embodiment of the invention connected via a line device, in which line device g a measuring arrangement for detecting the flow prevailing in the line device is provided

As an alternative to obtaining the signals indicative of the respiratory gas flow in this way, it is also possible to generate these signals by means of a measuring arrangement which has a measuring channel section with a defined channel narrowing.There is preferably a pressure tapping point within the narrowed channel section and immediately before or after it In a preferred embodiment of the invention, the pressures prevailing at the respective tapping points are detected by means of a differential pressure detection device and evaluated taking into account a characteristic curve determined for this measuring arrangement Further details and features result from the following description of several preferred exemplary embodiments of the invention in conjunction with the drawing

1 is a simplified perspective view of a device for supplying a breathing gas according to a first preferred embodiment of the present invention,

Fig. 2 is a simplified Pnnzipdarstellung of a device for feeding

Breathing gas according to a second embodiment of the present invention,

Fig. 3 is a diagram for explaining the control side considered

Transmission behavior of the compensation path a,

Fig. 4 is a simplified perspective view of another preferred

Embodiment of the invention with a breathing hose system whose device-side hose connection structure is formed in several parts

5 shows a simplified schematic diagram to explain a measuring arrangement which is preferably provided in the device according to the invention,

6 shows a simplified sectional view of an alternative measuring arrangement to the measuring arrangement shown in FIG. 5,

7 shows a simplified sectional view through a CPAP device with a measuring arrangement

The device for supplying a breathing gas shown in FIG. 1 comprises a breathing gas request device accommodated in a housing 1, here formed by a blower device (not visible). The breathing gas drawn in by the blower device via an inlet area 2 is guided through channels formed in the housing 1 to a humidification device which are also in the housing 1 is recorded

The moistening device comprises a liquid container 3, which can be removed from the housing 1 for refilling or cleaning. The liquid received in the liquid container 3 can be heated by a heating device. The heating device in the device shown is formed by a microwave heating device. The liquid container 3 is Made of a transparent glass or plastic material The breathing gas required by the blower device enters the liquid container through an upper opening and absorbs moisture in the process. The humidified breathing gas then reaches an outlet port onto which a ventilation hose 4 is attached

The breathing tube 4 is formed from a flexible material and provided with a spiral insert. In the embodiment shown here, the breathing tube 4 is formed in two parts from two halves of approximately the same length and joined together by means of a connecting sleeve 5

The ventilation hose 4 is provided with a measuring line 6, which extends partly inside, partly outside the ventilation hose. The measuring line 6 is passed inwards into the ventilation hose 4 here via the connecting sleeve 5. The measuring line 6 is so inside the above the connecting sleeve 5 Ventilation tube 4 fixes that the front end e is spaced a distance upstream from the front end E of the ventilation tube. The distance a between the two ends e, E is such that a compensating space Q is formed between the measuring point defined locally by the end e of the measuring line and the breathing mask identified here by the reference numeral 7, the volume of which is at least 9 ^* D ^* A , where D is the inside diameter of the breathing tube and A is the cross-sectional area thereof. By pulling off the connecting sleeve 5, the measuring line 6 can be pulled out of the breathing tube 4 in a simple manner

The measuring line 6 is centered in the region of the end e inside the breathing tube 4. For this purpose, a centering element 8 is shown, which is only indicated here and which has three foot elements arranged in a star-like manner, which have a cross-section of current. The test line 6 is led out of the connecting sleeve and is fastened to the respiratory tube 4 by several retaining clips 9. On the device side, the test line 6 is coupled to a measuring connection provided on the housing 1 via a connector 10 fastened to the respiratory tube 4

As an alternative to the embodiment shown with a long (two-part) ventilation hose 4, it is also possible to place the connecting sleeve 5 directly on the outlet connection provided on the humidifier side and to connect the shortened measuring line accordingly. The pressure levels measured via the measuring line at the upstream end of the equalization chamber Q are determined by a computer device arranged in the housing 1 processes taking into account the current respiratory gas volume flow or indicative signals in this regard

A further embodiment of the invention is shown in simplified form in FIG. 2. In the embodiment shown, the measuring point is located directly at the outlet of the humidifier identified here overall by reference number 11 and thus in a section lying downstream of a humidification zone. On the conventionally used part routed in the breathing gas line Measuring hose can be completely dispensed with here. In addition to the liquid container 3, the humidifier 11 comprises a device 12 for spiral-like swirling of the supplied breathing gas. As a result, the breathing gas is more intensively humidified and the noise generated on the blower side is further improved. The measuring point is via the measuring line 4 coupled to a pressure sensor p which in turn is connected to an AID converter 13. The AID converter 13 is connected to a control arrangement 14

This control arrangement processes a large number of input variables such as, for example, the blower device speed determined via a speed sensor and possibly also the power consumption of the drive motor of the blower device 5. In this embodiment, the measuring line section guided in the breathing tube 4 in the first embodiment is completely dispensed with, resulting in a particularly low breathing resistance The control arrangement 14 shown additionally processes signals on the basis of body potentials of the person to be ventilated which is recorded by electroencephalography. For this purpose, an intermediate computer 16 and an electrode 17 connected to it and suitable for self-application are merely shown

3 schematically shows the transmission behavior of the compensation chamber Q taken into account by the control arrangement 14. Both during inhalation and during exhalation, the pressure gradient arising via the compensation chamber Q is determined on the basis of a stored map or a stored function as a function of the instantaneous volume flow

4 shows a further preferred exemplary embodiment of the invention. The components explained in the context of the preceding description are provided here with the same reference symbols

In the embodiment shown here, a measuring tube lead-through element 20 is provided in front of the connector 10 provided for connecting the breathing tube 4, via which the measuring line 6, which is designed here as a measuring tube, is inserted into the breathing tube 4 Detachably connected In the arrangement shown, it is possible to pull the ventilation hose and the measuring line as one unit from the connection section on the device side and then in a simple manner to pull the measuring line 6 or the measuring hose together with the measuring hose lead-through element from the ventilation hose 4. The length ratio proposed by the invention Measuring tube and breathing tube is advantageously achieved by fixing the measuring tube in the measuring tube lead-through element 20. The breathing tube 4 is here ve Shown briefly The measuring hose led out of the ventilation hose is connected in the side area of the device via a corresponding connection structure to an electrical pressure transducer provided in the interior of the housing 1. The inner diameter of the ventilation hose 4 is preferably in the range of approx. 18 to 35 mm in the range of 4 to 8 mm The measuring arrangement of a preferred embodiment of the invention shown in FIG. 5 is integrated in a CPAP device

In the measuring arrangement shown, a first dynamic pressure tap element 21 and a second dynamic pressure tap element 22 are provided, which in the embodiment shown here are connected to one another via a measuring line 23a and 23b. A volume flow detection device 24 is provided in the measuring line 23a, 23b, via which the measuring line 23a , 23b flowing gas flow is detected. The breathing gas flow V in the breathing gas line 25 can be determined on the basis of this volume flow detected in this way

As an alternative to the volume flow detection device 24 shown, it is also possible to provide a differential pressure detection device here and thus only to detect the differential pressure between the pressure levels determined by the dynamic pressure tapping elements 21 and 22

In the embodiment shown here, the dynamic pressure tap elements 21 and 22 are formed by two pipe sockets, which are each aligned essentially perpendicular to a longitudinal central axis 26 of the breathing gas line 25 and extend near the inner wall of the breathing gas line. The first dynamic pressure tap element 21 has a first pressure tap opening 27a, which is located on an upstream side wall section of the dynamic pressure tap element 21

A second pressure tap opening 27b provided on the second dynamic pressure tap element 22 is located on a side surface section of the dynamic pressure tap element 22 facing downstream. The dynamic pressure tap elements 21 and 22 described can alternatively also be integrated into a single measuring element

Downstream of the device formed by the dynamic pressure tapping elements 21 and 22 for generating signals indicative of the respiratory gas flow, there is a pressure tapping point 28 for detecting the static pressure within the breathing gas line 25 after this respiratory gas humidifier In the embodiment shown here, the pressure tapping point 28 is connected via a thin hose line 29 to a transducer 30. This transducer 30 is connected to a control arrangement 32 via a data line 31. This control arrangement 32 is also used to indicate the signals indicative of the volume flow detection device with regard to the respiratory gas flow a further measuring line 34 is supplied

The signals supplied to the control arrangement 32 via the measurement line 31 and the measurement line 34 are taken into account in the control arrangement 32 when regulating the delivery rate of a blower, in particular controlling the speed of a motor of the blower. The control arrangement advantageously comprises at least one memory device for this purpose , in which a predetermined evaluation procedure and in particular also non-linear relationships between respiratory gas flow and pressure drop are stored

The control procedures stored in the storage device or implemented in the control arrangement can preferably be changed, in particular via an interface device. The storage device is preferably at least partially formed by an exchangeable memory card

As an alternative to the arrangement described above for detecting the signals indicative of the respiratory gas flow, it is also possible to obtain these signals by a measurement arrangement shown in simplified form in FIG. 6. In the measurement arrangement shown in FIG. 6, a constriction 35 is formed in the respiratory gas line 25 by Which a defined narrowing of the passage cross section of the breathing gas line 2 is achieved. In the embodiment shown, the pressure in the breathing gas line 25 is detected in a region immediately before the constriction 35 via a first pressure tap 36. The static pressure in the area of the constriction 35 can be determined via a second pressure tap 37 be determined

The levels tapped at the two pressure tapping points 36 and 37 can be fed analogously to the measuring arrangement shown in FIG. 5 to a transducer 30 ', by means of which the signals indicative of the respiratory gas flow are in turn generated. to compensate for the described measuring arrangement The measuring arrangement described in FIG. 6 is also advantageously located in the immediate vicinity of a blower device inside a CPAP device

FIG. 7 shows a CPAP device of this type which has a breathing gas delivery device formed here by a blower device 38. The delivery rate of the blower device, in particular the speed of an impeller of the blower device, is controlled by the control arrangement 32, which is only shown here in simplified form. The speed of the impeller is controlled here the control arrangement 32 is controlled both taking into account the respiratory gas flow and depending on the static pressure which is preferably tapped within a CPAP device or is still tapped in the vicinity of the CPAP device within the respiratory gas line. The detection of the signals indicative of the respiratory gas flow is simplified here illustrated device, a dynamic pressure detection device is provided, the structure of which essentially corresponds to the dynamic pressure detection device described above in connection with FIG. 5. In the embodiment shown here i In contrast to the embodiment described in FIG. 5, the pressure sensor for detecting the pressure within the breathing gas line 25 is formed by an electronic pressure sensor which is directly connected to the control arrangement 32 without the intermediary of the measurement transducer 30, which is often provided in FIG. 5, when using the actual CPAP Device downstream of the breathing gas humidification device, it is possible to provide the pressure drop point for determining the pressure prevailing within the breathing gas line immediately after the breathing gas humidification device. If appropriate, a further transducer is provided for this purpose, which optionally couples via a short connecting hose to an area of the breathing gas line following the humidification device

The control arrangement 32 is designed in such a way that it compensates for the pressure drop between the pressure drop point 28 and the mask-side end of the breathing tube in order to take into account the current breathing gas flow. This makes it possible to dispense with the pressure measuring tube that was previously usually required inside the breathing tube. This significantly reduces the pressure Breathing resistance and simplified cleaning of the breathing tube achieved The transmission behavior of the hose line following the pressure drop point 28 is taken into account within the control arrangement 32 by means of corresponding characteristic diagrams or functions. The transmission behavior of this measuring section is essentially determined by the cross section of the breathing gas hose and the length of the breathing gas hose. With the arrangement described, the pressure prevailing within a respiratory mask can be set within an extremely small tolerance range. The device is preferably provided with an adjusting device by means of which the tube resistance, the tube length or the V-dependency can be set

The regulation takes place under the objective that:

Pstat + v ² p / 2 + v ² ς + Y ( _d p / dt) = Psoii (t)

In which. p _stat = static pressure at the pressure measuring point, p = density of the breathing gas, v = velocity of the breathing gas in the range of

Pressure drop point, ξ = resistance coefficient of the breathing gas line in the area between the pressure drop point and the mouth to the mask, possibly from a map, P _so iκ _t > = current static setpoint pressure level in the area of the breathing mask, Y = correction coefficient for the pressure storage behavior of the

Breathing gas line

Claims

claims

1 device for supplying a breathing gas to a patient, with a blower device (38) for supplying the breathing gas, a breathing gas line for supplying the breathing gas from the blower device to a breathing mask, a first device for generating signals representative of the breathing gas flow or changing with the breathing gas flow , a second device (28, 29, 30) for generating signals indicative of the respiratory gas pressure, and a control arrangement (32) for controlling the blower device (38) on the basis of both the respiratory gas flow and the indicative signals regarding the respiratory gas pressure

2. Apparatus according to claim 1, characterized in that the control arrangement is designed such that it determines on the basis of the indicative of the respiratory gas flow signals between a pressure tap (28) and a respiratory mask-side end of the breathing tube pressure drop

3 Apparatus according to claim 2, characterized in that the control arrangement (32) in the context of an inspiration process sets the delivery pressure generated by the delivery device (38) to a higher pressure level corresponding to the expected pressure drop along the breathing gas line

4. The device according to at least one of claims 1 to 3, characterized in that the control arrangement (32) adjusts the pressure generated by the delivery device to a pressure level corresponding to the expected pressure drop along the breathing gas line as part of an expiration process

5 Device according to at least one of claims 1 to 4, characterized in that the device for generating the signals indicative of the respiratory gas flow in the area of the blower device (38) angeord¬

6. The device according to at least one of claims 1 to 5, characterized in that the device for generating the signals indicative of the respiratory gas flow has a dynamic pressure detection device or a measuring channel section with a defined line constriction (35)

7. The device as claimed in claim 6, characterized in that the device for generating the signals indicative of the respiratory gas flow has a first dynamic pressure tap opening (27a) opposite to the breathing gas demand direction and a second pressure tap opening (27b) facing away from the breathing gas demand direction

8. The device according to claim 7, characterized in that the two dynamic pressure tapping openings (27a, 27b) are connected via a line device (23a, 23b), and in that a flow measuring device (24) is provided for measuring the current in the line device (23a, 23b) )

9. The device according to at least one of claims 1 to 8, characterized in that a differential pressure measuring device is provided for measuring a pressure difference between the first and the second dynamic pressure tap opening (27a, 27b

10 Device according to at least one of claims 1 to 9, characterized in that the device for generating indicative signals with respect to the respiratory gas flow detects the speed of the blower motor or the blower output reference indicative signals

ERSATZB.LATT (RULE 26)

1 1 Device according to claim 6, characterized in that a differential pressure detection device is provided for detecting a pressure difference between a pressure decrease point in the area of the constriction (35) and an area immediately before or after the constriction (35)

12 Device according to at least one of claims 1 to 1 1, characterized in that the control arrangement is designed such that it detects the engine power reference and the pressure prevailing at the pressure measuring point and adjusts the engine power as a function of these two detected variables such that the pressure in the range the measuring point reaches an amount corresponding to the instantaneous pressure drop between mask and pressure measuring point above (inspiration phase) or below (expiration phase) the ventilation target pressure

13 Device for supplying a breathing gas to a patient with

a blower device for the breathing gas,

a control arrangement for controlling the demand for the breathing gas,

a breathing tube for supplying the breathing gas to a breathing mask, and

- A pressure detection device for generating a pressure signal for the control arrangement, wherein the pressure detection device detects the pressure in the region of the ventilation hose at a measuring point which is spaced upstream from a hose end on the mask side and a control arrangement is provided which takes the delivery capacity of the turbine into account with regard to the current one Breathing gas flow indicative signals and the pressure level detected at the measuring point controls such that during an inspiration process at the measuring point there is a pressure level that deviates from a target mask pressure by a differential pressure amount that corresponds to the pressure drop between the mask and the measuring point that is dependent on the current breathing gas flow

14 Device according to claim 13, characterized in that between the measuring point and the mask-side hose end a compensation section extends the length of which corresponds at least to 9 times the inner diameter of the breathing tube

15. The apparatus according to claim 13 or 14, characterized in that the measuring point is arranged downstream of a humidification zone formed in the humidification device

16. The device according to at least one of claims 13 to 15, characterized in that the measuring point corresponds locally to the location of the mouth of a measuring line inserted into the ventilation hose line

17. The apparatus according to claim 16, characterized in that the measuring point is arranged in a breathing gas line section extending between the ventilation hose line and the humidification zone

18. The apparatus according to claim 16, characterized in that the measuring point is located in the region of the ventilation hose line.

19. The device according to at least one of claims 13 to 18, characterized in that the control arrangement comprises a computing device which takes into account the transmission behavior of the section of the ventilation hose line between the measuring point and the mask-side end of the hose line as a function of the current breathing gas flow.

20. The device according to at least one of claims 13 to 19, characterized in that the measuring line is formed by a hose guided within the ventilation hose line, the length of which within the ventilation hose line is shorter than the ventilation hose line by more than 9 times the inner diameter of the ventilation hose line

21. The apparatus according to claim 20, characterized in that the measuring line is coupled to a sleeve element which can be connected to a device-side end section of the ventilation hose line 22 Device according to claim 21, characterized in that the measuring line is led out of the breathing gas supply path via the sleeve element

23 Control arrangement for controlling the supply of a breathing gas to a breathing mask by means of a blower device connected via a breathing gas line device, characterized in that the control arrangement is designed such that the current breathing gas flow is determined and that, based on the current breathing gas flow, the expected pressure drop along the breathing gas line device between the blowing device and the breathing mask is calculated, and the speed or the delivery rate of the blower device is adjusted, taking into account the expected pressure drop, such that the pressure inside the breathing mask reaches a predetermined target pressure level

24 Control arrangement according to claim 23, characterized in that it varies the target pressure level during a breathing cycle

25 control arrangement according to claim 24, characterized in that the time course of the desired pressure level is matched to the current state of a breathing person,

26 control arrangement for controlling the supply of a breathing gas to a breathing mask by means of a blower device connected via a breathing gas line device, in particular according to one of claims 23 to 25, characterized in that the course over time of the desired pressure level is matched to the current brain activity of the breathing person

27 Control arrangement according to at least one of claims 23 to 26, characterized in that it sets the time course of the target pressure level in accordance with the current sleep state 28 Control arrangement according to at least one of Claims 23 to 27, characterized in that the brain activity is detected by means, in particular electrodes, attached to the body, in particular to the head,

29 Control arrangement according to claim 28, characterized in that the brain activity is detected using an electrode attached to the forehead of the breathing person