WO2023222622A1

WO2023222622A1 - Respiratory apparatus, valve device and method for operating a respiratory apparatus

Info

Publication number: WO2023222622A1
Application number: PCT/EP2023/063010
Authority: WO
Inventors: Dietmar Enk
Original assignee: Dietmar Enk
Priority date: 2022-05-16
Filing date: 2023-05-15
Publication date: 2023-11-23
Also published as: DE102022112209A1

Abstract

The invention relates to a respiratory apparatus (1) at least comprising: a gas supply device (2) for supplying a first fluid flow to an airway (4) of a patient; a gas removal device (5), for removing a second fluid flow (6) out of the airway (4) and back into the respiratory apparatus (1) or the surroundings (7) of the patient; a control device (8) for operating the respiratory apparatus (1); and at least one first valve (9); wherein the first valve (9) is arranged on a first line (10) which is fluidically connected to the airway (4); wherein the airway (4) can be switchably fluidically connected to the surroundings (7) via the first valve (9) depending on a first pressure (11) present in the airway (4); wherein the surroundings (7) have an atmospheric pressure and an unlimited volume. The invention further relates to a valve device (25) and to a method for operating a respiratory apparatus (1).

Description

Ventilator, valve device and method for operating a ventilator

The invention relates to a ventilation device for ventilating a patient, a valve device and a method for operating a ventilation device.

The artificial ventilation of a patient using a ventilation device requires that the patient can tolerate the ventilation either through sufficiently deep sedation or anesthesia (“artificial coma”) or due to muscular weakness in the long course of the disease. If the depth of sedation is no longer sufficient or the anesthesia wears off and the patient's breathing drive resumes, most ventilation devices support spontaneous breathing attempts. The associated short-term pressure reductions within the ventilation cycle or process, which occur when the patient tries to breathe spontaneously, can “trigger” the ventilation device. The ventilation device builds up a preset pressure by insufflating breathing gas. If the ventilator works synchronously with the patient's spontaneous breathing attempts, this leads to gentle support for the patient's initially inadequate breathing. Over time, it is usually possible to wean the patient from the ventilator by gradually reducing the pressure support.

However, while a patient is being ventilated, it can happen that the patient actually works against the ventilation device (e.g. by attempting to inhale too strongly and/or coughing or straining). Insufficient or asynchronous support of the patient's spontaneous breathing attempts by the ventilation device can lead to strongly negative pressures, a lack of pressure relief and ventilation that continues against the patient's resistance can lead to very high pressures in the lungs or in the patient's airway. In particular, strongly negative pressures can cause damage to lung tissue and, consequently, a deterioration in lung function (both lung mechanics and gas exchange). This is what it is for The term “P-SILI” (“patient self-inflicted lung injury”) was coined. However, very high pressures can occur, especially in critically ill patients, e.g. B. require medical circulatory support, lead to circulatory instability or even circulatory collapse with the need for resuscitation.

Depending on the technical conditions of the ventilator and/or the selected settings, a ventilator is not necessarily able to adequately compensate for the negative pressure caused by inhalation attempts by increasing the gas flow or fluid flow with which the breathing gas is insufflated, or by coughing or presses to reduce or quickly and largely or even completely reduce the pressure generated in the airway or lungs. However, the latter makes sense in order to first eliminate the ventilation stimulus, to allow the patient to calm down and then to carefully start ventilation again.

The object of the present invention is to at least partially solve the problems mentioned with reference to the prior art. In particular, a ventilation device is to be proposed which further improves artificial ventilation of a patient. A valve device should also be proposed which, for. B. can be connected to a conventional ventilation device so that artificial ventilation of a patient can be improved. Furthermore, a method for ventilating a patient is to be proposed, through which artificial ventilation of a patient can be improved.

A ventilation device with the features according to patent claim 1, a valve device according to patent claim 17 and a method according to patent claim 19 contribute to solving these tasks. Advantageous further training is the subject of the dependent patent claims. The features listed individually in the patent claims can be combined with one another in a technologically sensible manner and can be supplemented by explanatory facts from the description and/or details from the figures, with further embodiment variants of the invention being shown. A ventilation device is proposed, at least comprising a gas supply device for supplying a first fluid stream to an airway (a lung) of a patient, a gas removal device for discharging a second fluid flow from the airway back into the ventilation device (i.e. e.g. into the environment the patient's separate collecting volume for the used and possibly contaminated breathing air) or to an environment (of the patient), a control device for operating the ventilation device and at least one first valve.

The first valve is arranged on a first line which is fluidly connected to the airway. Via the first valve, the airway can be fluidly connected to the patient's environment in a switchable manner depending on a first pressure present in the airway.

The environment has in particular an atmospheric pressure, i.e. e.g. B. between 980 and 1020 mbar [millibar], and an unlimited volume. Unlimited volume means in particular that neither the temperature nor the pressure in the environment changes due to the supply of the (third) fluid stream flowing into the environment via the first valve, precisely because the volume of the environment is so large.

In particular, the first valve releases the (third) fluid stream flowing via the first valve directly to the environment, i.e. H. No (relevant) flow resistance (e.g. no second or third line, but possibly a fourth line) is provided downstream of the first valve.

The third fluid stream can, if necessary, be removed via a fourth line and, if necessary, cleaned.

A gas supply device includes in particular a gas source for breathing gas, e.g. B. for oxygen or an oxygen-nitrogen mixture or air and a (second) line for supplying the first fluid stream to the respiratory tract. The breathing gas source is e.g. B. a pressure vessel from which the first fluid flow over the Ventilation device can be transported to the respiratory tract. The breathing gas required for an inspiration process (corresponding to inhalation) can be provided via the gas supply device.

In addition to the breathing gas, the first fluid stream can also contain additives, e.g. B. contain medication, moisture, etc.

A gas discharge device comprises at least one (or the second or a separate third) line for diverting the second fluid flow from the airway back to the ventilator or to the environment. The gas discharge device can also have a (second) valve for throttling or controlled (partial) release of this line. This allows e.g. B. an uneven pressure reduction in the lungs and airway due to the elastic restoring forces of the patient's respiratory system (i.e. chest, respiratory muscles, lungs, airway) can be evened out.

In particular, the gas removal device comprises a suction device through which the second fluid stream can be sucked out of the respiratory tract at least temporarily. In particular, by using a suction device, the entire expiration process (corresponding to an exhalation) can be controlled with regard to the volume flow of the second fluid flow and the pressure curve in the airway.

The control device is particularly suitably equipped, configured or programmed for operating the ventilator. In particular, at least one or more or all of the following parameters can be controlled by the control device: the first fluid flow, the second fluid flow, a third fluid flow flowing through the first valve, a pressure curve of the first pressure in the respiratory tract, a composition of the first fluid flow, etc. .

The first line, in particular fluidly, connects the first valve to the airway. In particular, the first fluid stream can be supplied to the respiratory tract via a second line. In particular, the second fluid stream can be removed from the respiratory tract via the second line. If necessary, a separate third line can be provided, via which the second fluid flow from the respiratory tract is discharged. The first line can be designed separately from the other lines and can be fluidly connected to the other lines (exclusively) via the respiratory tract. If necessary, the first line can also be connected to the second line and/or to the third line or via this to the airway.

The second line can z. B. be formed at least partially by a (ventilation) tube that extends over the throat into the patient's trachea. The second line can also be formed by another lumen inserted endotracheally (i.e. into the trachea). In particular, it is also possible for the second line to include a larynx or face mask or a (closed) hood through which the patient is ventilated.

The first pressure is in particular the current pressure present in the airway or the pressure on the basis of which the ventilation of the patient is aligned by the ventilation device. The first pressure is monitored in particular by a pressure sensor. This can detect the first pressure directly in the airway (measured) or, if the pressure sensor is arranged at a distance from the airway, calculate it. To calculate the first pressure, in particular the fluid flows supplied into the airway or removed from the airway are recorded or measured.

In particular, a first valve (with the function of a pressure relief valve) arranged close to the tube or close to the airway is proposed, which z. B. if the patient tries to inhale too hard and therefore (too) low pressure in the ventilation system and the lungs (or in the airway) and/or if the patient coughs or strains and therefore (too) high pressure in the ventilation system and the lungs (or . in the airway) opens the airway to the environment with a short latency, i.e. keeps it open in particular for a (e.g. programmable) period of time, then closes it again and thus enables controlled or assisted ventilation via the gas supply device and gas discharge device.

In particular, the first valve connects when the pressure is too low Ventilation system and the lungs (or in the airway) and / or if the pressure in the ventilation system and the lungs (or in the airway) is too high, the airway with the environment, i.e. in particular for a (e.g. programmable) period of time. The valve then closes again (usually when the pressure is again within the intended limits), so that controlled or assisted ventilation via the gas supply device and gas discharge device is then possible again.

In particular, the first valve is arranged via the fluid connection of the first line at a distance of at most 60 cm [centimeters], in particular at most 45 cm, preferably at most 30 cm, from the airway. In particular, the body that opens and closes the first valve is arranged at the stated distance from the airway. The outlet on the valve towards the environment is preferably arranged at the stated distance from the respiratory tract.

The distance extends in particular from a distal end of the first line (if it opens directly into the airway) or from a distal end of the second or third line (if the first line is fluidly connected to the airway via the second or third line ) up to the first valve, i.e. up to the body of the first valve or the outlet.

In particular, the dead volume of at least the first line present between the first valve and the airway is at most 200 ml [milliliter], preferably at most 100 ml. The dead volume is the volume that is between the opening into the airway and the first valve (or the Body of the first valve or the outlet). The dead volume is therefore formed at least by the first line, if necessary additionally via the second or third line.

In particular, a flow resistance of the first line, ie from the airway to the first valve or to the environment, is also as low as possible, so that a (third) fluid flow can be drained from or fed into the airway as effectively as possible via the first valve . In particular, the ventilation device completely obstructs the patient's airway, so that a fluid flow is supplied and removed exclusively via the ventilation device, ie via the gas supply device, the gas discharge device and, if necessary, the first valve. For example, the ventilation device can have a cuff (a dilation element) through which the airway is fluidly separated from the environment surrounding the patient.

In particular, the first fluid stream is supplied past the first valve and until an end-inspiratory (peak) pressure set on the gas supply device or on the control device is reached. The first valve connects the airway to the environment (only) when or after a first pressure is exceeded, which is greater than the end-inspiratory pressure and exceeds this by a maximum of 10 mbar, preferably a maximum of 5 mbar, particularly preferably a maximum of 2 mbar. The first valve switches in particular even when the pressure is exceeded, but at least also when the pressure is exceeded, which is between greater than zero and 10 mbar.

In particular, the second fluid stream is discharged past the first valve until an end-expiratory pressure set on the gas discharge device or on the control device is reached. The first valve connects the airway with the environment (only) when or after falling below a first pressure, which is smaller than the end-expiratory pressure and is below this by at most 10 mbar, preferably at most 5 mbar, particularly preferably at most 2 mbar. The first valve switches in particular even when the pressure falls below a relatively high level, but at least also when the pressure falls below zero and is between greater than zero and 10 mbar.

In particular, the first valve can be implemented by two separate first valves, with one first valve connecting the airway to the environment when or after the first pressure is exceeded and the other first valve connecting the airway to the environment when or after the first pressure is exceeded. after the first pressure falls below. In particular, the ventilation device additionally comprises a suction device, wherein the control device is set up to independently control the second fluid flow (starting from the end-inspiratory (peak) pressure) through the suction device during an expiration process until the end-expiratory pressure is reached.

In particular, the first valve switches with a sensitivity of at most 2 mbar, preferably at most 1 mbar. Sensitivity here means that the switching point of the first valve, i.e. H. the switching from the closed state to the open state has a maximum deviation (of at most 2 mbar or at most 1 mbar) from a preset switching point.

In particular, the at least one first valve switches automatically. In particular, the first valve is z. B. designed as a one-way valve, which z. B. can be switched to an open state against a return spring. In particular, the at least one first valve (then) comprises two first valves, the one first valve z. B. when the end-inspiratory pressure is exceeded and the other first valve z. B. switches automatically when the end-expiratory pressure falls below.

In particular, the at least one first valve can be switched by the control device. In particular, the ventilation device comprises a pressure sensor which determines or detects the current first pressure (measured), the control device being set up to actuate the at least one first valve as a function of a signal from the pressure sensor. The first valve is z. B. an electromagnetically operated valve.

In particular, the control device is set up to open the at least one first valve depending on the first pressure and thus to connect the airway with the environment and also to close it again independently of the first pressure and thus to separate the airway from the environment. In particular, the control device can program a time for which the first valve remains in the open state when it is opened became. The open state of the first valve can then be maintained regardless of the further course of the first pressure.

In particular, the control device is set up to operate the ventilation device and thus to adjust a course of the first pressure during at least one ventilation process, i.e. at least during an inspiration process and / or an expiration process, the at least one first valve being switchable by the control device and thus the airway with the Environment can be connected. In particular, the control device is set up to switch the first valve when the first pressure deviates by at least 2 mbar from a predetermined profile of the first pressure.

The first valve connects the airway with the environment (only) when or after the first pressure deviates from the predetermined course by at least 2 mbar. The first valve switches in particular when there is a deviation of at most 10 mbar, preferably at most 5 mbar, and then connects the airway with the environment. The first valve switches in particular even when the first pressure deviates from the predetermined course, but at least also when the deviation is between 2 mbar and 10 mbar.

In particular, this can also be done during ventilation, i.e. if the patient is e.g. B. is ventilated by the ventilator with fluid streams, a pressure reduction or pressure build-up in the airway takes place via the third fluid stream, which is discharged from the airway or supplied to the airway via the first valve.

In particular, the ventilation device additionally comprises a second line, via which the airway is fluidly connected to the ventilation device, with the at least one first valve being arranged on the second line.

In particular, a filter is arranged along the first line and thus between the airway and the at least one first valve, so that only a (third) fluid stream flowing through the first valve passes through the filter applied. The filter protects in particular the first valve from contamination and moisture and the patient's airway from the ingress of particles and the bronchial mucous membranes from heat loss and drying out.

In particular, the control device is set up so that when the at least one first valve is switched and the airway is connected to the environment, the ventilation device can be operated in such a way that a first fluid stream can be supplied to the airway via the gas supply device. In particular, the first fluid stream can thus continue to be supplied to the airway during the inspiration process. In particular, a pressure drop in the first pressure caused by the opened first valve can be at least partially or completely controlled during the expiration process by continuing to supply the first fluid stream to the airway via the second line.

In particular, the control device is set up so that if the first valve is switched during the supply of the first fluid stream and the airway is connected to the environment and at least as long as the first valve is switched, a volume flow and / or an oxygen content of the first fluid stream can be increased. In particular, the oxygen content in the respiratory tract can be kept at a high or desired level (and increased compared to the environment). In particular, when the first valve is opened, a third fluid stream is supplied from the environment and into the respiratory tract via the first valve. The third fluid stream has the atmospheric ratio of oxygen and nitrogen, which may not be sufficient to ventilate a patient. For this reason, when the airway also receives the third fluid stream, the volume flow and/or the oxygen content of the first fluid stream is increased so that the oxygen content in the airway drops as little as possible.

A valve device is further proposed, at least comprising at least one first valve, a pressure sensor for determining a current first pressure present in a patient's airway, and a valve control device which is set up to actuate the at least one first valve as a function of a signal from the pressure sensor. The Valve device is with a (conventional) ventilation device, at least comprising a gas supply device for supplying a first fluid stream to the patient's respiratory tract, a gas discharge device for discharging a second fluid flow from the respiratory tract and a control device for operating the (conventional) ventilation device, to form the described Ventilation device connectable or connected. The first valve is then arranged on a first line which is fluidly connected to the airway. Via the first valve, the airway can be fluidly connected to an environment of the patient depending on a first pressure present in the airway, the environment having an atmospheric pressure and an unlimited volume.

In particular, the airway is fluidly connected to or separated from the patient's environment via the first valve depending on a first pressure present in the airway, the environment having an atmospheric pressure and an unlimited volume.

A valve device is therefore proposed which can be combined with conventional ventilation devices. In terms of function, this combination results in the ventilation device described above. The control device of the conventional ventilation device can continue to regulate the ventilation, in particular (exclusively) the function of the first valve, i.e. the opening and closing of the first valve, being controllable by the valve control device.

In particular, the first valve is actuated by the valve control device independently of the ventilation being controlled by the control device.

A method for operating a ventilation device is also proposed, in particular for operating the ventilation device described. The ventilation device comprises at least a gas supply device for supplying a first fluid stream to a patient's airway, a gas discharge device for discharging a second fluid stream from the Airway back into the ventilator or to an environment, a control device for operating the ventilator and at least one first valve. The first valve is arranged on a first line which is fluidly connected to the airway, wherein the airway can be fluidly connected to an environment of the patient via the first valve depending on a first pressure present in the airway, the environment being atmospheric pressure and an unlimited volume.

The method comprises at least the following steps: a) operating the ventilation device and at least supplying the first fluid stream via the gas supply device until an end-inspiratory pressure is reached and/or discharging the second fluid stream via the gas discharge device until an end-expiratory pressure is reached; and,

• if the first pressure is greater than the end-inspiratory pressure and exceeds it by a maximum of 10 mbar or

• if the first pressure is smaller than the end-expiratory pressure and falls below it by a maximum of 10 mbar, or

• if the control device is set up to operate the ventilation device and thus to adjust a course of the first pressure during at least one ventilation process, i.e. at least during an inspiration process and / or an expiration process, and the at least one first valve can be switched by the control device and thus the airway with the environment can be connected and the first pressure deviates by at least 2 mbar from a predetermined course of the first pressure, b) switching the at least one first valve and connecting the airway to the environment. The above (non-exhaustive) division of the process steps into a) and b) is primarily intended to serve as a distinction and not to impose any order and/or dependency. The frequency of the process steps e.g. B. during setup and/or operation of the system may vary. It is also possible for process steps to at least partially overlap each other in time. In particular, step b) is conditional and may only be carried out if the conditions mentioned are met. In particular, step a) will otherwise be carried out. In particular, steps a) and b) are carried out in the order listed.

In particular, the method includes that an alarm signal is generated by the ventilator when the first valve is switched. The alarm signal is in particular an optical and/or acoustic and/or electrical alarm signal.

The comments on the ventilation device can be transferred in particular to the valve device and the method and vice versa.

A control device is also proposed which is equipped, configured or programmed to carry out the method described.

Furthermore, the method can also be carried out by a computer or with a processor of a control device.

A data processing system is therefore also proposed which includes a processor which is adapted/configured in such a way that it carries out the method or part of the steps of the proposed method.

A computer-readable storage medium may be provided which includes instructions which, when executed by a computer/processor, cause it to carry out the method or at least part of the steps of the proposed method. The statements on the method can be transferred in particular to the ventilation device, the valve device and/or the computer-implemented method (i.e. the computer or the processor, the data processing system, the computer-readable storage medium) and vice versa.

The first valve is in particular an electromagnetic valve. Using a suitable adapter (e.g. a standard T-piece), to which the second or third line of the ventilator can also be connected, the first valve is connected directly to a tube (or a larynx or face mask ) plugged in. Compared to valves that are located in an anesthesia machine or in an intensive care ventilator, dead volume and flow resistance can be minimized because the first valve opens close to the tube or at a short distance from the airway when activated.

In an embodiment variant of a first valve, there can be a perforated diaphragm with a typically but not necessarily fixed diameter (e.g. 9 mm) in a (screwable and therefore removable) threaded cap, which is closed in a pressure-tight manner by a rubber cone. The rubber cone sits on an electromagnetically movable piston, which is pulled into an electromagnetic coil against spring pressure (with a stroke of, for example, approx. 2.5 mm) when activated or when switching and thus opening the first valve. This releases the pinhole and a third fluid flow passes through openings in a threaded ring onto which the threaded cap with the pinhole is screwed.

In addition to the perforated diaphragm, which is typically fixed in terms of diameter, the diameter of the openings in the threaded ring can generally be varied: This can be done, for example. B. done by means of another ring with openings, which lies above the threaded ring and can be rotated against it, so that the free area of the openings in the two superimposed rings can be varied. Technically, the closing/opening mechanism of the first valve can also be implemented. However, shorter latency times and better sealing make a closing/opening mechanism using a pinhole and a rubber cone on an electromagnetically movable piston advantageous appear.

The first valve can be completely dismantled, in particular for disinfection, and is therefore reusable.

The first valve is inserted into a filter in particular by means of a standard connector, preferably a so-called “heat and moisture exchange” filter (HME filter), which protects the first valve from contamination and moisture and the patient's airway from the ingress of particles protects the bronchial mucous membranes from heat loss and drying out.

Essentially, there are two particular configurations for connecting the first valve to a tube (or a larynx or face mask):

According to a first embodiment, the first valve is connected behind a filter (which protects the first valve from contamination and moisture and the patient's airway from ingress of particles and the bronchial mucous membranes from heat loss and drying out) on the side leg of a standard T-piece . The pressure measurement is carried out either via the ventilator, with which the first valve communicates in particular via a data interface and/or is controlled by it, or via a separate pressure measuring line, which is preferably connected to a pressure measuring catheter or .Pressure sensor or alternatively connected to the port of the filter, which is normally used to take a breathing gas sample for analysis purposes (e.g. carbon dioxide content), but also enables a pressure measurement in front of the tube and thus indirectly in the respiratory tract.

According to a second embodiment, the first valve is connected behind a filter (which protects the first valve from contamination and moisture and the patient's airway from ingress of particles and the bronchial mucous membranes from heat loss and drying out) to a special adapter, which is in particular next to an access for a pressure measurement catheter or pressure sensor at least one standard connection for e.g. B. the filter with plugged-in first valve as well as another standard connection for e.g. B. has a (closed) suction system or a bronchoscopy port and also a ventilation connection (preferably with a Luer lock connection) for a ventilation device or a second and / or third line or an (additional) controllable breathing gas source (e.g B. has a compressed gas source or a turbine-driven “blower”) with which (additional) breathing gas can be supplied to and/or removed from the respiratory tract.

The first valve or the valve device includes in particular a manually operated programming and control unit (the valve control device), which either forms a (structural) unit with the first valve, but is preferably located in a housing that is separate from the first valve or in the ventilator is integrated.

The first pressure is measured in particular by means of a pressure measuring line (possibly in combination with a pressure measuring catheter) or a pressure sensor either in front of the tube (e.g. on the filter of the first valve), in the tube or preferably tracheally (i.e. in the trachea). The latter allows for the most accurate measurements of the first print.

The first pressure is measured as absolute pressure using a pressure sensor installed in the programming and control unit, but is typically output as relative pressure, i.e. as pressure above or below the (current) ambient air pressure (the atmospheric pressure or pressure of the environment).

The ambient air pressure, which can also be measured as absolute pressure via a second pressure sensor, preferably installed in the programming and control unit, serves as a reference pressure which is subtracted from the first pressure measured in front of the tube, in the tube or preferably tracheally. The pressure limits (to be set) at which the first valve opens are also, in particular, relative pressures.

Various solutions are possible with regard to communication with the ventilation device and, if necessary, an (additional) controllable breathing gas source: In a so-called “stand alone” solution, the first valve can be operated completely independently of the ventilation device by its programming and control unit or its valve control device. The first pressure is measured in particular via a separate pressure measuring line (possibly in combination with a pressure measuring catheter) or a separate pressure sensor.

The valve control device is in particular able to alarm itself, i.e. to generate an alarm signal (locally and preferably also in the direction of a control center) and to output an alarm history (which can be used to adjust the patient's sedation depth if necessary in the event of repeated alarms). If necessary, the volume flow or the (fourth) fluid flow of an (additional) adjustable breathing gas source is also differentiated by the valve control device. The alarm can e.g. B. always be triggered when the first valve changes to the open state. The alarm includes in particular an optical and/or acoustic and/or electrical alarm signal.

The "stand alone" solution is particularly interesting in combination with conventional ventilation devices (and conventional ventilation modes such as VCV - "volume-controlled ventilation", PCV - "pressure-controlled ventilation", BiPAP - "biphasic positive airway pressure" , APRV - “airway pressure release ventilation”), which cannot themselves be retrofitted with a valve control device for the first valve.

In a so-called combined solution, the first valve communicates with its valve control device, in particular at least temporarily with the ventilator or with the control device of the ventilator (e.g. with regard to the acceptance of pressure measurement data from the ventilator). The pressure limits or switching points of the first valve are entered in particular at the valve control device, which also monitors the first pressure and / or its course, typically issues alarms (locally and preferably also in the direction of a control center) and controls the first valve. If necessary, the differentiated control of a (fourth) fluid flow of an (additional) adjustable breathing gas source by the valve control device.

In a so-called integrated solution, the first valve communicates completely (or largely completely) with the ventilator or the control device and/or an (additional) adjustable breathing gas source (e.g. with regard to the acceptance of pressure measurement data from the ventilator, the programming of the pressure limits the ventilator, the monitoring of the first pressure and the control of the first valve by the ventilator or the control device, possibly also differentiated control of a (fourth) fluid flow of an (additional) adjustable breathing gas source by the ventilator).

In the “stand alone” solution and the combined solution, the operating elements for the valve control device are located either directly on the first valve or preferably on the valve control device (possibly on a housing arranged separately from the first valve), whereas in the integrated solution they are preferably located the ventilator.

The functionality of the first valve is described again below: If a set lower or upper pressure limit (e.g. below the end-expiratory pressure or above the end-inspiratory pressure) is undershot or exceeded, the first valve opens and then remains in particular opens for a programmed time and then closes again (whereby the ventilation of the patient by the ventilator device restarts or continues).

In particular, the lower pressure limit is set somewhat lower than the one selected on the ventilator or, alternatively, the actually measured lowest first pressure within the ventilation process (e.g. the end-expiratory pressure). The upper pressure limit, on the other hand, is set in particular slightly higher than the one selected on the ventilator or, alternatively, the actually measured highest first pressure within the ventilation process (e.g. the end-inspiratory (peak) pressure). The first valve is in particular pressure-controlled.

In particular, the valve control device of the first valve communicates with the Ventilation device during the ventilation process, so that differentiated control of the first valve is possible, e.g. B. the first valve can be switched if there is a deviation from a programmed pressure curve. The first valve can z. B. can be switched when the first pressure suddenly (relatively speaking) drops or rises during the inspiration process or the expiration process, so that the airway is fluidly connected to the environment.

When the first valve is triggered or opened, the first fluid flow of the ventilator is preferably increased in the direction of the patient. It makes sense if a fluid connection between the airway and the environment is opened via the first valve and the patient can breathe in air through the open first valve, the first fluid flow (to the patient) and possibly also the oxygen concentration in the (supplied) To increase breathing gas in order to prevent a relevant drop in the oxygen concentration in the gas inhaled by the patient (as a result of the third fluid flow supplied to the respiratory tract from the environment via the first valve).

A relevant decrease in the oxygen concentration can only occur due to mixing of the respiratory gas (first fluid stream that the patient inhales) with ambient air (third fluid stream) if the maximum gas flow of inhalation on the part of the patient exceeds the (possibly increased) respiratory gas flow on the part of the ventilator (if necessary in combination with an (additional) controllable breathing gas source). Nevertheless, for safety reasons, especially in critically ill patients, an increased first fluid flow with 100% oxygen should be considered, which is provided either by the ventilation device or an (additional) controllable breathing gas source.

For a certain fluid flow, the deciding factor is basically the resistance of the open first valve, possibly together with the resistance of the filter (upstream of the first valve), on the one hand, and the resistance, for example. B. the tube (or the larynx or face mask) as well as the resistances in the airway or in the patient's lung tissue on the other side determine how much fluid/gas goes to the patient or into the airway when the first valve is open of the patient flows. Inhalation or exhalation (attempts) by the patient influence the (actual) fluid flow into or out of the patient's airway.

The first valve and possibly the filter (upstream of the first valve) typically have small, but still relevant resistances. When the first valve is open, a slightly positive pressure is created in the patient's airway (in the sense of a so-called PEEP =) by a possibly (automatically) adjusted, higher first fluid flow depending on the resistance of the open first valve and possibly the filter (upstream of it). “Positive end-expiratory pressure”) is built up and maintained as long as the patient is not breathing. The resulting pre-expansion of the lungs is (usually) very useful from a breathing mechanical point of view.

The resistance of the open first valve, possibly together with the resistance of the filter (upstream of the first valve), defines the amount of pressure that can build up depending on the first fluid flow. An increase in the first fluid flow always leads to an increase in pressure, while a decrease in it always leads to a decrease in pressure.

The (possibly increased) first fluid flow can be provided by the actual ventilation device or also by a further source of breathing gas, which is then preferably directly controlled by the valve control unit of the first valve. The further breathing gas source can e.g. B. can be connected via an adapter on which the first valve, possibly with an upstream filter, is installed. With an adapted first fluid flow (from a conventional ventilation device and/or possibly an (additional) adjustable breathing gas source), pressure support during the inspiration process (in the sense of assisted to controlled ventilation) is not only possible when the first valve is closed, but even when it is open. possible.

In particular, conventional ventilation devices are only able to control the increase in volume and the increase in pressure in the airway or the lungs during the inspiration process. The decrease in volume and the drop in pressure in the airway or lungs during the expiration process However, they are not (actively) controlled by conventional ventilation devices. At the end of the inspiration process, only the ventilation pressure is removed from the airway or the lungs, which leads to a (passive) outflow of gas from the airway or the lungs, the amount of which is determined by the restoring forces of the lungs and chest as well as the outflow resistances in the airway or the lungs. the patient's lungs and the ventilation device.

On the other hand, with a first valve in combination with a ventilator and/or an (additional) controllable breathing gas source, gas outflow control during the expiration process can also be implemented as follows: At the moment when the first valve opens, the first fluid flow from the ventilator and/or an (additional) controllable breathing gas source in the direction of the patient is increased in such a way that the pressure in the airway or the lungs is initially maintained (in the sense of a plateau pressure phase) and then by reducing the first fluid flow from the ventilator and / or an (additional ) adjustable breathing gas source falls slowly and in a controlled manner.

The amount of volume flow required for this depends in particular on the dimensioning of the (free) opening area of the first valve: with a smaller opening area and thus higher resistance of the first valve it is smaller, but with a larger opening area and thus lower resistance it is larger. Due to the slowly decreasing back pressure that is built up in this way, the breathing gas escapes slowly and in a controlled manner from the airway or lungs. This imitates a physiological exhalation, which keeps the lungs more homogeneously ventilated. The resulting better volume expansion (also referred to as “compliance”) of the lungs reduces the work of breathing that the patient has to do.

But even in a ventilation device that can fully control both the inspiration and expiration processes (e.g. by suction and thus control of the second fluid flow), a first valve makes sense, especially if the ventilation device has a resistance that is a makes it impossible for the patient to breathe independently on this device (i.e. with the ventilation device closed to the environment). The first valve then acts as a “pressure monitor” and ensures that no pressures that are too low or too high, potentially harmful, can build up in the patient's airway or lungs.

By means of the first valve described and suitable control (in particular with short latency times) of the fluid flows and the first valve, a simple, pressure-controlled ventilation device (without rebreathing or recirculation of breathing gas via a carbon dioxide absorber) can also be constructed for assisted and/or controlled ventilation consists only of a fluid supply leg and a (typically very short) fluid discharge leg with an attached first valve. The fluid supply leg and the fluid discharge leg are always connected to one another and are not separated by valves to control the fluid flow direction, as is the case with conventional ventilation devices. Furthermore, the pressure built up towards the patient during the expiration process is controlled by an adapted first fluid flow when the first valve is open.

The problem of less accurate breathing gas monitoring (e.g. measuring the carbon dioxide concentration in the exhaled breathing gas) resulting from the inevitable mixture of fluid/gas in front of the tube can be solved by taking a deep, preferably tracheal, sample of breathing gas (e.g. via a catheter). can be solved very easily.

In this ventilation device, the first valve is typically closed during the inspiration process, which allows precise volumetry of the insufflated, typically oxygen-rich breathing gas. When the programmed ventilation pressure is reached, the first valve opens while at the same time the volume flow of the first fluid stream is increased. At this moment, the supplied fluid preferably comes from a compressed air source or a turbine-driven air “blower”, as this allows oxygen to be saved. By opening the first valve intermittently and only for a short time, the pressure built up can initially be maintained (in the sense of a plateau pressure phase), before the pressure drops, preferably slowly and steadily, to a programmed, end-expiratory value by successively reducing the volume flow of the first fluid stream during the expiration process. Once this pressure is reached, the first valve closes again (if necessary after a new plateau pressure phase) for the subsequent inspiration process.

If the complete stop of the first fluid flow from the breathing gas source, especially towards the end of the expiration process, with lower restoring forces from the lungs and chest, does not lead to a sufficiently rapid outflow of breathing gas (second fluid flow) from the patient's lungs, exhalation can be supported and thus shortened During the expiration process, breathing gas may also be sucked in via the openings of the first valve using negative pressure (if such suction is not possible via the ventilation device). In principle, this makes it possible to have the same respiratory gas flow during the inspiration process and the expiration process (and therefore a time ratio of 1 to 1 between the inspiration process and the expiration process), which has energetic advantages.

The first valve or the valve device has further possible applications, in particular in intensive care medicine, which will be explained below:

For hygienic reasons, closed suction systems are now mostly used to remove secretions from the respiratory tract, especially for patients on long-term ventilators. If you suck for too long, significant pressure can build up in the patient's lungs. The associated reduction in the peripheral gas volume in the lungs (the so-called functional residual capacity), from which the patient receives oxygen, can endanger the patient's oxygen supply. A first valve can reliably prevent this. The first valve opens and air can flow in, which is then quantitatively sucked out (along with the secretion to be removed), so that more oxygen-rich gas remains in the lung periphery.

The possibility of this in patients on long-term ventilation is also clinically interesting to test and monitor the often disturbed function of the diaphragm (as the most important respiratory muscle): In this way, the maximum negative pressure that can be achieved when the respiratory gas flow is stopped (for the measurement) during an inspiration process or an attempt to inhale by the patient with an initially opened, then briefly for the measuring maneuver When the first valve is closed and then opened again, it can be used as a relative measure of the force of the diaphragm.

Another measuring maneuver with temporary closure of the first valve (during a spontaneous breathing attempt with an otherwise open ventilator) and a constant first fluid flow (from the ventilator or an (additional) controllable breathing gas source) is interesting from a functional aspect: As long as a patient is during an inspiration process or a Inhalation attempt with the first valve then closed cannot produce a pressure drop in the upper airways, the first fluid flow from the ventilator or an (additional) controllable breathing gas source is always higher than the breathing gas flow that the patient can generate on his own. In this case, the patient receives constant pressure support. However, if there is a (brief) drop in pressure in the upper airways during the inspiration process or the inhalation attempt, the patient can generate a higher (peak) flow. The first valve can therefore help to estimate the (peak) flow during an inspiration process or an inhalation attempt with an otherwise open ventilator only against the resistance of the tube and in the patient's airway or lung tissue (i.e. without additional resistance in the ventilator). Like the measurement maneuver described above, this is also an interesting parameter, especially when weaning from ventilation (so-called “weaning”).

For patients on long-term ventilation, monitored training of the diaphragm is also possible by intermittent, programmable closure of the first valve during successively longer spontaneous breathing phases with the first valve open and adapted breathing gas flow. The training then consists e.g.

B. in that the patient triggers the first valve to inhale and To do this, the programmed negative pressure must be generated for opening the first valve. If the patient succeeds in doing this more and more often, this indicates increasing strength of the diaphragm.

As part of the weaning from mechanical ventilation, the patient can open the first valve intermittently and for a programmed time both by attempting to inhale (and thereby falling below the set lower pressure limit) and by gently pressing (and thereby exceeding the set upper pressure limit). Breathe independently at low airway resistances (which are close to physiological ones). The open first valve, with its typically fixed (alternatively variable) opening cross-section, takes on the important function of the glottis as an “exhalation brake”. The frequency with which the patient triggers the first valve is also a possible criterion for assessing the progress of “weaning”. Accordingly, the initially rather short opening phases of the first valve can be successively extended. However, if longer spontaneous breathing phases are to be enabled with the first valve open, it is recommended to monitor the respiratory rate as (a) parameter for (incipient) exhaustion of the patient, since direct measurement of the tidal volume is not possible due to the ventilator being open (with the first valve open). .

The first valve or valve device also offers advantages when inducing anesthesia and/or manual ventilation of a patient: If the first valve (with an upstream filter) is plugged onto a face mask using a suitable adapter, so-called pre-oxygenation (before induction of anesthesia) is also possible. possible with a high oxygen flow without the risk of the spontaneously breathing patient being inflated with (too) high pressure when the face mask is (ideally) tightly fitting: If the patient presses, the first valve opens. When the first valve is open, only a slightly positive pressure in the sense of a PEEP (as described above) remains - again depending on the resistance of the open first valve (with an upstream filter) and on the gas flow (first fluid flow). The gas flow (first fluid flow) can also come from a simple, controllable breathing gas source (e.g. oxygen bottle or - wall connection with flow regulator), i.e. a complex ventilation device is not necessary.

Finally, the first valve can reliably prevent (too) high ventilation pressures even during (subsequent) manual ventilation using a hand resuscitator.

The use of indefinite articles (“a”, “an”, “an” and “an”), particularly in the patent claims and the description reflecting them, is to be understood as such and not as a numeral. Terms or components introduced accordingly are to be understood as meaning that they are present at least once and, in particular, can also be present multiple times.

As a precaution, it should be noted that the number words used here (“first”, “second”, ...) primarily serve (only) to distinguish between several similar objects, sizes or processes, i.e. in particular no dependency and/or order of these objects, sizes or prescribe processes to each other. If a dependency and/or sequence is required, this is explicitly stated here or it will be obvious to the person skilled in the art when studying the specifically described embodiment. To the extent that a component can occur multiple times (“at least one”), the description of one of these components can apply equally to all or part of the majority of these components, but this is not mandatory.

The invention and the technical environment are explained in more detail below using the accompanying figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments given. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and combine them with other components and findings from the present description. In particular, it should be noted that the figures and in particular the proportions shown are only schematic. Show it: Fig. 1: a ventilation device with a valve device;

Fig. 2: a first diagram;

Fig. 3: a second diagram;

Fig. 4: a third diagram;

Fig. 5: a first embodiment variant of a ventilation device; and

Fig. 6: a second embodiment variant of a ventilation device.

1 shows a ventilation device 1 with a valve device 25. The valve device 25 comprises a first valve 9, a pressure sensor 17 for determining a current first pressure 11 present in the airway 4 of a patient and a valve control device 26, which is used to actuate the first valve 9 is set up depending on a signal 18 from the pressure sensor 17. The valve device 25 is equipped with a (conventional) ventilation device 1, at least comprising a gas supply device 2 for supplying a first fluid stream 3 to the patient's airway 4, a gas discharge device 5 for discharging a second fluid stream 6 from the airway 4 and a control device 8 for operation the (conventional) ventilation device 1, to form the ventilation device 1 described. The first valve 9 is arranged on a first line 10, which is fluidly connected to the airway 4. The first line 10 extends from the first valve 9 to a distal end 30 which is arranged in the airway 4.

Via the first valve 9, the airway 4 can be fluidically connected to the patient's environment 7 depending on a first pressure 11 present in the airway 4, the environment 7 having an atmospheric pressure and an unlimited volume. The ventilator 1 further comprises a control device 8 for operating the ventilator 1 (possibly also together or in communication with the valve control device 26).

A third fluid stream 24 flows directly to the environment 7 via the first valve 9, i.e. H. No flow resistance is provided downstream of the first valve 9.

A gas supply device 2 comprises a gas source for breathing gas, e.g. B. for oxygen or an oxygen-nitrogen mixture or air, as well as an at least partially separate second line 22 for supplying the first fluid stream 3 to the respiratory tract 4. The breathing gas source is z. B. a pressure container from which the first fluid stream 3 can be transported via the ventilator 1 to the respiratory tract 4. The breathing gas required for an inspiration process 20 can be provided via the gas supply device 2. The second line 22 extends from the gas supply device 2 to the first line 10 or via the first line 10 to the airway 4.

A gas discharge device 5 comprises an at least partially separate third line 27 for diverting the second fluid flow 6 from the airway 4 back to the ventilation device 1 or to the environment 7. The gas discharge device 5 can have a (second) valve (not shown) for throttling or controlled (partial) Release the third line 27. This allows e.g. B. an uneven pressure reduction in the airway 4 due to the elastic restoring forces of the patient's respiratory system can be evened out. The third line 27 extends from the gas discharge device 5 to the second line 22.

The first line 10 fluidly connects the first valve 9 to the airway 4. The first fluid stream 3 can be supplied to the airway 4 via the second line 22. The second fluid stream 6 can be discharged from the airway 4 via the second line 22 (and the third line 27). The first line 10 is only partially designed separately from the second line 22. The first line 10 is connected to the second line 22 or connected via this to the airway 4.

The first valve 9 is arranged via the fluid connection of the first line 10 at a distance 12 of at most 60 cm from the airway 4. The distance 12 extends from the distal end 30 of the first line 10 or the second line 22 to the first valve 9.

The dead volume 13 of the first line 10, which is present between the first valve 9 and the airway 4 and extends over the distance 12, is at most 200 ml. The dead volume 13 is the volume that is between the mouth (the distal end 30) of the first line 10 is located in the airway 4 and the first valve 9.

The second line 22 can z. B. be formed at least partially by a tube that extends over the throat to the patient's airway 4. The second line 22 is shown in FIG. 1 as an endotracheally inserted lumen.

The first pressure 11 is the current pressure present in the airway 4 or the pressure on the basis of which the ventilation of the patient is directed by the ventilation device 1. The first pressure 11 is monitored by a pressure sensor 17. This can be the first print 11, e.g. B. via a pressure measuring catheter extending into the airway 4, directly in the airway 4 (measured). Alternatively, the first pressure 11 can also be determined via a pressure measurement on the first valve 9, on the filter 23 or in the first line 10, in which case a conversion to the first pressure 11 present in the airway 4 takes place.

With the first valve 9 arranged close to the airway 4 (with the function of a pressure relief valve) z. B. if the patient tries to inhale too hard and as a result (too) low pressure in the ventilation system and the lungs (in the airway 4) and/or if the patient coughs or strains and as a result (too) high pressure in the ventilation system and the lungs (in the airway 4) the airway 4 is opened to the environment 7 with a short latency. The The first valve 9 can remain open for a (e.g. programmable) time 28, then close again and thus enable controlled or assisted ventilation via the gas supply device 2 and gas discharge device 5 (see also FIGS. 2 to 4).

The ventilation device 1 completely covers the patient's airway 4, so that a fluid flow 3, 6, 24 can be supplied and removed exclusively via the ventilation device 1, i.e. H. via the gas supply device 2, the gas discharge device 5 and possibly via the first valve 9. For example, the ventilation device 1 can have a cuff (a dilation element) through which the airway 4 is fluidly separated from the environment 7 surrounding the patient.

The supply of the first fluid stream 3 takes place past the first valve 9 and until reaching a final inspiratory (peak) pressure 14 set on the gas supply device 2 or on the control device 8. The first valve 9 connects (only) at or after Exceeding a first pressure 11, which is greater than the end-inspiratory pressure 14 (and exceeds this by a maximum of 10 mbar or more), the airway 4 with the environment 7.

The second fluid stream 6 is discharged past the first valve 9 and until an end-expiratory pressure 15 set on the gas discharge device 5 or on the control device 8 is reached. The first valve 9 connects (only) when or after the pressure falls below a first pressure 11, which is smaller than the end-expiratory pressure 15 and is below this by a maximum of 10 mbar, the airway 4 with the environment 7.

The ventilation device 1 additionally comprises a suction device 16, the control device 8 being set up to independently control the second fluid flow 6 (starting from the end-inspiratory (peak) pressure 14) through the suction device 16 during an expiration process 21 until the end-expiratory pressure 15 is reached . The first valve 9 can be switched by the control device 8 or the valve control device 26. The ventilation device 1 comprises a pressure sensor 17, which determines or detects the current first pressure 11 (measured), the control device 8 being set up to actuate the first valve 9 as a function of a signal 18 from the pressure sensor 17. The first valve 9 is an electromagnetically operated valve.

The control device 8 or the valve control device 26 is set up to open the first valve 9 depending on the first pressure 11 and thus to connect the airway 4 with the environment 7 and also to close it again independently of the first pressure 11 and thus the airway 4 to separate from the environment 7. The control device 8 or the valve control device 26 can be used to program a time 28 for which the first valve 9 remains in the open state when it has been opened. The open state of the first valve 9 can then be maintained regardless of the further course 19 of the first pressure 11.

This means that this can also be done during ventilation, for example when the patient is B. is ventilated by the ventilation device 1 with fluid streams 3, 6, a pressure reduction or pressure build-up in the airway 4 takes place via the third fluid stream 24, which is discharged from the airway 4 or fed into the airway 4 via the first valve 9.

The control device 8 is set up to operate the ventilation device 1 and thus to set a course 19 of the first pressure 11 during at least one ventilation process 20, 21, that is to say at least during an inspiration process 20 and/or an expiration process 21, the first valve 9 being controlled by the control device 8 can be switched and so that the airway 4 can be connected to the environment 7. The control device 8 can also be set up to switch the first valve 9 when the first pressure 11 deviates from a predetermined curve 19 of the first pressure 11 by at least 2 mbar.

A filter 23 is arranged along the first line 10 and thus between the airway 4 and the first valve 9, so that only one via the first Valve 9 flowing third fluid stream 24 acts on the filter 23. The filter 23 protects the first valve 9 from contamination and moisture and the patient's airway 4 from the ingress of particles and the bronchial mucous membranes from heat loss and drying out.

The control device 8 is set up so that when the first valve 9 is switched and the airway 4 is connected to the environment 7, the ventilation device 1 can be operated in such a way that a first fluid stream 3 can be supplied to the airway 4 via the gas supply device 2. The first fluid stream 3 can thus continue to be supplied to the airway 4 during the inspiration process 20. Furthermore, during the expiration process 21, a pressure drop in the first pressure 11 caused by the opened first valve 9 can be at least partially or completely controlled by further supplying the first fluid stream 3 to the airway 4 via the second line 22.

The control device 8 is set up so that when the first valve 9 is switched during the supply of the first fluid stream 3 and the airway 4 is connected to the environment 7 and at least as long as the first valve 9 is open, the volume flow and / or the oxygen content of the first Fluid flow 3 can be increased. This allows the oxygen content in the airway 4 to be kept at a high or desired level (and increased compared to the environment 7). When the first valve 9 is opened, a third fluid stream 24 can be supplied from the environment 7 and to the airway 4 via the first valve 9. The third fluid stream 24 has the atmospheric ratio of oxygen and nitrogen, which, however, may not be sufficient for ventilation of a patient. For this reason, when the airway 4 also receives the third fluid stream 24, the volume flow and/or oxygen content of the first fluid stream 3 is increased, so that the oxygen content in the airway 4 drops as little as possible.

Fig. 2 shows a first diagram. Fig. 3 shows a second diagram. Fig. 4 shows a third diagram. The diagrams are described together below. Reference is made to the comments on FIG. 1. The diagrams each show the course 19 of the first pressure 11 and the first fluid flow 3 as well as the second fluid flow 6 during ventilation that is completely controlled by a ventilation device 1.

In the upper part of each diagram, the first pressure 11 is plotted on the vertical axis and the time 28 is plotted on the horizontal axis.

In the diagrams, the alternating inspiration processes 20 and expiration processes 21 are plotted over the course of time 28.

In the lower part of each diagram, the fluid flows 3, 6 are plotted as volume flow on the vertical axis and the time 28 is plotted on the horizontal axis.

It can be seen that in the diagrams, as a rule, the first fluid stream 3 and the second fluid stream 6 are each supplied or discharged as a constant volume flow. This results in a sawtooth profile of the course 19 of the first pressure 11, see the first and third ventilation processes with inspiration process 20 and expiration process 21.

With this type of ventilation (with constant volume flow), the effects of the ventilation device described here are particularly clearly visible. However, the ventilation device is by no means limited to this type of ventilation.

Furthermore, it can be seen in the first diagram in FIG. 2 that towards the end of the second inspiration process 20 the end-inspiratory pressure 14 is exceeded. In this example, the first fluid stream 3 is stopped when the end-inspiratory pressure 14 is exceeded, whereby the inspiration process 20 is shortened.

The first valve 9 switches and a third fluid stream 24 is delivered to the environment 7 via the first valve 9.

In this example, the fluid flows 3, 6 generated by the ventilator are zero for the time 28 in which the first valve 9 is open. 2 shows that as soon as the third fluid flow 24 and the first pressure 11 reach zero and the expiration process 21 can therefore be viewed as ended, the first valve 9 remains open for the remaining time 28 of a regular ventilation process until the next one Inspiration process 20 starts and the control device 8 supplies a first fluid stream 3 to the airway 4. The inspiration process 20 takes longer because the pressure build-up begins at zero.

The open state of the first valve 9 can be coupled to the course 19 of the first pressure 11 and/or to the respective fluid flows 3, 6, 24, which can be detected individually or collectively by the control device 8.

In the second diagram in Fig. 3 it can be seen that when the end-expiratory pressure 15 falls below the first valve 9 switches and a third fluid stream 24 is sucked in from the environment 7 by the patient via the first valve 9. The inspiration process 20 ends when a third fluid stream 24 is no longer sucked in from the environment 7 via the first valve 9. The first valve 9 remains open for a programmed time 28, which in this example is longer than a regular expiration process 21 lasts. During the expiration process 21, the third fluid stream 24 is released into the environment 7 via the first valve 9. As long as the first valve 9 is open, the fluid flow 3 always remains constant (shown in dotted lines under the third fluid flow 24 during the inspiration process 20), which results in a slightly positive pressure below the end-expiratory pressure 15 due to the outflow resistance of the filter 23 and the first valve 9 builds up. After closing the first valve 9, the ventilation device 1 again generates the sawtooth-like curve 19 of the first pressure 11 via the constant fluid flows 3, 6. The next inspiration process 20 takes a little longer because the pressure build-up begins below the end-expiratory pressure 15.

It can be seen that the curve 19 of the pressure 11 has a slight increase at the beginning of the second expiration process 21. This results from the increased fluid flow 24 at the beginning of this expiration process 21 and the fact that the patient not only exhales the fluid that he exhales through the opened first valve 9 has sucked in from the environment 7 (the third fluid stream 24), but also the first fluid stream 3, which was insufflated during the short inspiration process 20 caused by the gas supply device 2 (with the first valve 9 still closed).

In the third diagram in Fig. 4 it can be seen that a first pressure 11 during the inspiration process 20 deviates from the intended course 19 of the first pressure 11 or falls below it. In this example, the first valve 9 is only opened briefly and a third fluid stream 24 can be sucked in by the patient via the first valve 9. At the same time, however, the volume flow of the first fluid stream 3 (shown in dotted lines) and in particular the oxygen content in the first fluid stream 3 is increased in order to keep the proportion of oxygen in the breathing gas that is supplied to the patient sufficiently high.

Fig. 5 shows a first embodiment variant of a ventilation device 1. Reference is made to the comments on Fig. 1.

The valve device 25 comprises a first valve 9, a pressure sensor 17 for determining a current first pressure 11 present in the airway 4 of a patient, and a valve control device 26, which is set up to actuate the first valve 9 as a function of a signal 18 from the pressure sensor 17. The valve device 25 is equipped with a (conventional) ventilation device 1, at least comprising a gas supply device 2 for supplying a first fluid stream 3 to the patient's airway 4, a gas discharge device 5 for discharging a second fluid stream 6 from the airway 4 and a control device 8 for operation the (conventional) ventilation device 1, to form the ventilation device 1 described. The first valve 9 is arranged on a first line 10, which is fluidly connected to the airway 4. The first line 10 extends from the first valve 9 to a distal end 30 which is arranged in the airway 4.

The airway 4 is via the first valve 9 depending on one in which

Airway 4 present first pressure 11 switchable with the environment 7 of Patients can be connected fluidly, the environment 7 having an atmospheric pressure and an unlimited volume.

A third fluid stream 24 flows directly into the environment 7 via the first valve 9 or can be sucked in from the environment 7 via the first valve 9, i.e. H. No flow resistance is provided towards the surroundings 7 of the first valve 9.

A gas supply device 2 has a second line 22 for supplying the first fluid stream 3 to the airway 4. The breathing gas required for an inspiration process 20 can be provided via the gas supply device 2. The second line 22 extends from the gas supply device 2 to the first line 10 or via the first line 10 to the airway 4.

A gas discharge device 5 comprises a third line 27 for diverting the second fluid flow 6 from the airway 4 back to the ventilator 1 or to the environment 7. The gas discharge device 5 can have a (second) valve (not shown) for throttling or controlled (partial) release of the third Line 27 have. The third line 27 extends from the gas discharge device 5 to the second line 22. The second line 22 and the third line 27 are brought together via a Y-piece to form a common lumen. The Y-piece is connected to an adapter 31, which is additionally connected to or forms the first line 10. The filter 23 and the first valve 9 are arranged on the adapter 31.

The first line 10 fluidly connects the first valve 9 to the airway 4. The first fluid stream 3 can be supplied to the airway 4 via the second line 22. The second fluid stream 6 can be discharged from the airway 4 via the second line 22 (still in the Y-piece) and then via the third line 27. The first line 10 is connected to the second line 22 or via this to the airway 4. The first valve 9 is arranged via the fluid connection of the first line 10 at a distance 12 of at most 60 cm from the airway 4. The distance 12 extends from the distal end 30 of the first line 10 or the second line 22 to the first valve 9.

The aforementioned adapter can be connected to a tube, which then forms the first line 10 to the airway 4. The tube extends over the throat to the patient's airway 4.

The first pressure 11 is the current pressure present in the airway 4 or the pressure on the basis of which the ventilation of the patient is directed by the ventilation device 1. The first pressure 11 is determined and monitored by a pressure sensor 17 directly in the airway 4 or alternatively measured and monitored on the first valve 9, on the filter 23 or in the first line 10, with the valve control device 26 possibly converting it to that in the Airway 4 present first pressure 11 takes place.

6 shows a second embodiment variant of a ventilator 1. Reference is made to the comments on FIGS. 1 and 5. In contrast to the first embodiment variant, here the second line 22 and the third line 27 are formed by a common lumen. The ventilation device 1 is designed as a gas supply device 2 and gas discharge device 5, e.g. B. by a so-called gas flow reversing device according to WO 2015/004229 A1.

Here too, the second line 22 is connected to an adapter 31, which is additionally connected to or forms the first line 10. The filter 23 and the first valve 9 are arranged on the adapter 31. In addition, another device 29 can be connected to the adapter 31, e.g. B. a bronchoscopy port, a (closed) secretion suction device or an additional breathing gas source. Reference symbol list

Ventilation device Gas supply device first fluid flow Respiratory path Gas removal device second fluid flow Environment Control device first valve first line first pressure distance dead volume end-inspiratory pressure end-expiratory pressure suction device pressure sensor signal course

Inspiration process Expiration process second line Filter third fluid flow Valve device Valve control device third line Time

Device distal end adapter

Claims

Claims Ventilation device (1), at least comprising a gas supply device

(2) for supplying a first fluid stream

(3) towards an airway

(4) a patient, a gas removal device

(5) for discharging a second fluid stream

(6) from the airway (4) back into the ventilator (1) or to an environment

(7) the patient, a control device

(8) for operating the ventilation device (1) and at least one first valve (9); where the first valve

(9) on a first line

(10) is arranged, which is fluidly connected to the airway (4); wherein via the first valve (9) the airway (4) depends on a first pressure present in the airway (4).

(11) can be connected to the environment (7) via fluid technology; wherein the environment (7) has an atmospheric pressure and an unlimited volume. Ventilation device (1) according to claim 1, wherein the first valve (9) is at a distance via the fluid connection of the first line (10).

(12) is arranged at a maximum of 60 cm from the airway (4). Ventilation device (1) according to one of the preceding claims, wherein a dead volume present between the first valve (9) and the airway (4).

(13) at least the first line (10) is at most 200 ml. Ventilation device (1) according to one of the preceding claims, wherein the ventilation device (1) completely relocates the patient's airway (4), so that a fluid flow (3, 6) is supplied and discharged exclusively via the ventilation device (1). Ventilation device (1) according to one of the preceding claims, wherein the supply of the first fluid stream (3) takes place past the first valve (9) until a final inspiratory pressure (14) set on the gas supply device (2) is reached, the first valve (9) when a first pressure (11), which is greater than that, is exceeded end-inspiratory pressure

(14) and exceeds this by a maximum of 10 mbar, connects the airway (4) with the environment (7). Ventilation device (1) according to one of the preceding claims, wherein the discharge of the second fluid stream (6) takes place past the first valve (9) until an end-expiratory pressure (15) set on the gas discharge device (5) is reached; wherein the first valve (9) when the pressure falls below a first pressure (11), which is smaller than the end-expiratory pressure

(15) and falls below this by a maximum of 10 mbar, connects the airway (4) with the environment (7). Ventilation device (1) according to claim 6, additionally comprising a suction device (16), wherein the control device (8) is set up during an expiration process (21) by the suction device

(16) to independently control the second fluid flow (6) until the end-expiratory pressure (15) is reached. Ventilation device (1) according to one of the preceding claims, wherein the first valve (9) switches with a sensitivity of at most 2 mbar. Ventilation device (1) according to one of the preceding claims, wherein the at least one first valve (9) switches automatically. Ventilation device (1) according to one of the preceding claims 1 to 8, wherein the at least one first valve (9) can be switched by the control device (8); wherein the ventilation device (1) comprises a pressure sensor (17) which determines the current first pressure (11); wherein the control device (8) is set up to actuate the at least one first valve (9) as a function of a signal (18) from the pressure sensor (17). Ventilation device (1) according to claim 10, wherein the control device (8) is set up to have at least one first valve (9). Depending on the first pressure (11) to open and thus to connect the airway (4) with the environment (7) and also to close again independently of the first pressure (11) and thus to separate the airway (4) from the environment (7 ) to separate. Ventilation device (1) according to one of the preceding claims 10 and 11, wherein the control device (8) for operating the ventilation device (1) and thus for setting a course (19) of the first pressure (11) during at least one ventilation process (20, 21) , i.e. is set up at least during an inspiration process (20) or an expiration process (21); wherein the at least one first valve (9) can be switched by the control device (8) and the airway (4) can therefore be connected to the environment (7); wherein the control device (8) is set up to switch the first valve (9) when the first pressure (11) deviates by at least 2 mbar from the predetermined course (19) of the first pressure (11). Ventilation device (1) according to one of the preceding claims, additionally comprising a second line (22), via which the airway (4) is fluidly connected to the gas supply device (2) and the gas discharge device (5); wherein the at least one first valve (9) is arranged on the second line (22). Ventilation device (1) according to one of the preceding claims, wherein a filter (23) is arranged along the first line (10) and thus between the airway (4) and the at least one first valve (9), so that only one via the first Valve (9) flowing third fluid stream (24) acts on the filter (23). Ventilation device (1) according to one of the preceding claims, wherein the control device (8) is set up so that when the at least one first valve (9) is switched and the airway (4) is connected to the environment (7), the ventilation device (1 ) can be operated in such a way, in that a first fluid stream (3) can be supplied to the respiratory tract (4) via the gas supply device (2). Ventilation device (1) according to claim 15, wherein the control device (8) is set up so that when the first valve (9) is switched during the supply of the first fluid stream (3) and the airway (4) is connected to the environment (7). and at least as long as the first valve (9) is switched, at least a volume flow or an oxygen content of the first fluid flow (3) can be increased. Valve device (25), at least comprising at least one first valve (9), a pressure sensor

(17) for determining a current first pressure (11) present in a patient's airway (4) and a valve control device (26) which is used to actuate the at least one first valve (9) depending on a signal

(18) of the pressure sensor (17) is set up; wherein the valve device (25) with a ventilation device (1), at least comprising a gas supply device (2) for supplying a first fluid stream (3) to the patient's airway (4), a gas discharge device (5) for discharging a second fluid stream (6 ) from the airway (4) and a control device (8) for operating the ventilator (1), can be connected to a ventilator (1) according to one of the preceding claims; wherein the first valve (9) is then arranged on a first line (10) which is fluidly connected to the airway (4); wherein the airway (4) can be fluidly connected to an environment (7) of the patient via the first valve (9) depending on a first pressure (11) present in the airway (4), the environment (7) being atmospheric pressure and an unlimited volume. Valve device (25) according to claim 17, wherein actuation of the first valve (9) by the valve control device (26) takes place independently of a control of the ventilation by the control device (8). Method for operating a ventilation device (1), which has at least one gas supply device (2) for supplying a first fluid stream (3) to a patient's airway (4), a gas discharge device (5) for discharging a second fluid stream (6) from the airway (4) back into the ventilator (1) or to an environment (7) of the patient, a control device (8) for operating the ventilator (1) and at least one first valve (9); wherein the first valve (9) is arranged on a first line (10) which is fluidly connected to the airway (4); wherein the airway (4) can be fluidically connected to the environment (7) via the first valve (9) depending on a first pressure (11) present in the airway (4), the environment (7) having an atmospheric pressure and has an unlimited volume; wherein the method comprises at least the following steps: a) operating the ventilation device (1) and at least supplying the first fluid stream (3) via the gas supply device (2) until an end-inspiratory pressure (14) is reached or discharging the second fluid stream (6). the gas discharge device (5) until an end-expiratory pressure (15) is reached; and if the first pressure (11) is greater than the end-inspiratory pressure (14) and exceeds it by a maximum of 10 mbar or if the first pressure (11) is smaller than the end-expiratory pressure (15) and falls below it by a maximum of 10 mbar; or if the control device (8) is used to operate the ventilation device (1) and thus to set a course (19) of the first pressure (11) during at least one ventilation process (20, 21), i.e. at least during an inspiration process (20) or an expiration process (21) is set up and the at least one first valve (9) can be switched by the control device (8) and thus the airway (4) can be connected to the environment (7) and the first pressure (11) is at least 2 mbar from the predetermined course

(19) of the first pressure (11) deviates, b) switching the at least one first valve (9) and connecting the airway (4) to the environment (7).

20. The method according to claim 19, wherein an alarm signal is generated when the first valve (9) is switched by the ventilation device (1).