Arrangement for supplying a patient-side coupling unit with a gas mixture

Description

[0001] The invention relates to a supply arrangement for supplying a patient-side coupling unit with a gas mixture.

[0002] The invention can be used, for example, for the artificial respiration of a patient. A patient-side coupling unit, such as a breathing mask, catheter, or tube, is arranged in or on the patient's body. To artificially ventilate the patient, a gas mixture is delivered to the patient-side coupling unit. This gas mixture comprises oxygen and, in one embodiment, additionally at least one anesthetic. Preferably, a ventilator performs a sequence of ventilation strokes and delivers a quantity of the gas mixture to the patient-side coupling unit with each ventilation stroke.

[0003] It is possible to use breathing air as the gas mixture. Often, it is desired that the oxygen content of the gas mixture delivered to the patient-side coupling unit be greater than the oxygen content of the breathing air. To achieve this goal, a gas mixture comprising breathing air and pure oxygen is generated. The invention can be used to generate such a gas mixture and deliver it to the patient-side coupling unit.

[0004] A supply arrangement with the features of the preamble of claim 1 is known from US 3 664 361 A. Therein, a ventilation arrangement (respiration system) is described which mixes oxygen from a pressure-regulated source (10) with air from an air intake (11) and delivers the result of the mixing to a patient. The air is conveyed by means of a pump 13 from the inlet 11 via a first line 14, a component (manifold 19) and a second line 15 to a mixing unit (proportioning device 20). The oxygen is conveyed via lines 41, 53, 32 to the mixing unit 20. A mechanical regulator (control apparatus 33) adjusts the pressure of the oxygen in line 32 to sensed fluctuations in the pressure in line 14.The regulator 33 comprises a variable-volume reservoir 35, wherein the reservoir 35 comprises a fixed wall 43, a movable wall 45, and two foldable walls 47, and wherein an overpressure relative to the ambient pressure prevails in the reservoir 35. A balancing valve 37 opens and closes a balancing port 38 in a wall 43 between the reservoir 35 and the line 32. A diaphragm 39 is exposed on one side to the pressure in the line 32 and on the other side to a pressure which is exposed via a line 79 to the air pressure in the line 14.

[0005] The ventilation arrangement of US 4 549 563 A delivers a gas mixture comprising oxygen from a source 11 and nitrogen from a source 21 and optionally an anesthetic to a breathing mask on the face of a patient. The components of the gas mixture are mixed together in a mixing unit (circuit 3). A pressure reducer (pressure limiter 40) comprises two chambers 42 and 43 and a diaphragm (diaphragm 41) between the two chambers 42 and 43. The chamber 42 is connected to the source 21 and to a line 20, with the line 20 leading to the mixing unit 3. The chamber 43 is connected via a line 46 to a line 10, with the line 10 connecting the source 11 to the mixing unit 3.

[0006] The ventilator 14 of EP 2 425 869 A1 comprises a mixing device and a ventilation section. In the mixing device, a medical gas, for example, oxygen or an anesthetic, is mixed with air. The medical gas is fed in via a gas inlet B and supplied via a gas line 10. The air is fed in via an air inlet A and supplied via an air line 11. A reduction valve 6, a safety valve 7, a controllable proportional valve 8, and a flow meter 9 are arranged in the gas line 10. A blower 1 and a check valve 2 are arranged in the air line 11. The ventilation section supplies the gas mixture to a patient as breathing gas via a breathing gas line 12. A flow sensor 3, a controllable proportional valve 4, and a pressure sensor 5 are arranged in the breathing gas line 12. A control unit 13 receives signals from the sensors 9, 3 and is able to control all controllable valves 8, 4.

[0007] The invention is based on the object of providing a supply arrangement which is capable of supplying a patient-side coupling unit with a gas mixture comprising at least two gas components, wherein the temporal progression of the pressure of the provided gas mixture or the volume flow of the gas mixture to the patient-side coupling unit can be regulated in a relatively reliable manner.

[0008] The invention is achieved by a supply arrangement having the features of claim 1. Advantageous embodiments are specified in the subclaims.

[0009] The supply arrangement according to the invention is capable of supplying a patient-side coupling unit with a gas mixture. The gas mixture comprises a first gas component, for example, breathing air, and a second gas component, for example, pure oxygen. The gas mixture can comprise a third gas component, for example, an anesthetic.

[0010] The patient-side coupling unit is connected to a patient or can be connected to a patient at least temporarily. In particular, the patient-side coupling unit can be placed on the patient's face and / or inserted into the patient's body.

[0011] The term "channel" is used below. A channel is a component that can guide a fluid, especially a gas or gas mixture, along a predetermined trajectory and ideally prevents the fluid from leaving this trajectory. A hose and a tube are examples of a channel.

[0012] In addition, the following refers to a fluid connection being established between two components. This means that a fluid can flow from one component to the other, ideally without escaping into the environment. It is possible for the two components to be directly connected to one another. It is also possible for there to be a gap between the two components and for a fluid guidance unit, for example a hose, to connect the two components. It is possible for a fluid to temporarily flow from the first component through the fluid connection to the second component and temporarily vice versa, from the second component through the fluid connection to the first component. The fluid connection can be permanent or only temporary.

[0013] In the context of the invention, a "buffer storage" is understood to mean a component that can absorb and release a quantity of a fluid within its interior. It is possible for the volume of the buffer storage to change, with the buffer storage increasing when the gas is absorbed and decreasing again when the gas is released. It is also possible for the volume of the buffer storage to be constant, and for the buffer storage to temporarily store a fluid, in particular a gas, under excess pressure.

[0014] The buffer storage tank comprises at least one chamber within it, optionally several chambers. Each chamber can hold and release a fluid. If the buffer storage tank comprises at least two chambers, these two chambers are preferably fluid-tightly separated from each other and can hold different fluids.

[0015] Furthermore, the term "source" is used below. In the context of the invention, a source is capable of providing a fluid, in particular a gas component. A source is, in particular, a stationary supply connection or a mobile source, for example, a container containing the fluid, in particular a compressed air cylinder. It is possible to use at least two different sources, in particular a stationary source and a mobile source.

[0016] The supply arrangement according to the invention comprises a first channel with a supply connection element. A fluid connection is established or can be established at least temporarily between the supply connection element and a first source. This first source is a source for the first gas component.

[0017] The supply arrangement according to the invention further comprises a buffer reservoir. A supply chamber is arranged inside the buffer reservoir. A fluid connection is established or can be established permanently or at least temporarily between the supply chamber and a second source. This second source is a source of the second gas component. The second gas component is chemically different from the first gas component. It is possible for both gas components to comprise the same component, for example, both comprise oxygen. The supply chamber is capable of absorbing and releasing a quantity of the second gas component.

[0018] Furthermore, the supply arrangement according to the invention comprises a second channel. A supply fluid connection is established or can be established at least temporarily between the supply chamber and the second channel.

[0019] The first channel can conduct the first gas component from the supply connection element to a mixing point of the supply arrangement. The second channel can conduct the second gas component from the buffer storage to this mixing point. This allows the gas mixture comprising the first gas component and the second gas component to be generated at the mixing point. It is also possible for the gas mixture to form spontaneously at the mixing point.

[0020] The supply arrangement according to the invention further comprises an inspiratory channel. This inspiratory channel leads from the mixing point to the patient-side coupling unit and is capable of conveying a gas mixture generated at the mixing point from the mixing point to the patient-side coupling unit.

[0021] According to the invention, the first and second channels flow into the mixing point, and the inspiration channel begins at the mixing point. A gas mixture comprising the first and second gas components is created at the mixing point. In the simplest case, the mixing point is a purely mechanical component that connects these three channels like a Y-piece.

[0022] Furthermore, the supply arrangement according to the invention comprises a pneumatic control line. This control line establishes a control fluid connection between the first channel and the buffer reservoir. Thus, a fluid can flow from the first channel through the pneumatic control line to the buffer reservoir and, optionally, vice versa, from the buffer reservoir through the control line to the first channel. The term "pneumatic control line" distinguishes the control line according to the invention from a data line and an electrical line.

[0023] The buffer storage, the supply fluid connection and the control fluid connection work together to achieve the following effect: Between the pressure in the supply chamber, the pressure in the first channel and the pressure in the second channel Pressure equalization is achieved, even if the pressure downstream of the mixing point, and therefore also the pressure in the first channel and / or the pressure in the second channel, varies over time. During artificial ventilation of a patient, the pressure usually varies in at least one channel.

[0024] The invention makes it possible to deliver a gas mixture comprising at least two gas components to the patient-side coupling unit, thereby providing the gas mixture at or in the patient-side coupling unit for the artificial respiration of a patient. Because the supply arrangement is designed to compose the gas mixture from at least two gas components, the invention makes it possible in many cases to provide a gas mixture tailored to the patient's currently required artificial respiration. In particular, pure oxygen can act as the second gas component, and the proportion of oxygen in the gas mixture can be adjusted and changed as needed. An anesthetic can also act as the second gas component.

[0025] According to the invention, a buffer reservoir is arranged between the second source and the second channel. When the supply arrangement is used, the second gas component flows from the second source to the buffer reservoir, into and out of the supply chamber, and further from the buffer reservoir into the second channel. Thanks to the buffer reservoir, the control fluid connection, and the supply fluid connection, pressure equalization between the pressure in the first channel and the pressure in the second channel is automatically achieved. As a result, the pressure in the first channel and the second channel is approximately the same, even if the pressure in the first channel and / or the volume flow through the first channel vary over time. At the very least, a pressure difference is automatically reduced after a certain time delay.

[0026] These two temporally coincident pressures in the two channels facilitate mixing of the two gas components and automatic control of the volume flow and / or pressure of the gas mixture downstream of the mixing point. The goal of this optional closed-loop control is to ensure that the actual temporal progression of the volume flow or pressure in the inspiratory channel follows a predefined target temporal progression. This control, in turn, facilitates artificial ventilation of the patient, particularly with assisted artificial ventilation that supports the patient's own respiratory activity. In particular, the control facilitates synchronizing the ventilation strokes of a ventilator with the patient's own respiratory activity.

[0027] According to the invention, the pneumatic control line establishes a pneumatic control fluid connection between the first channel and the buffer reservoir. This creates a pressure equalization between the pressure in the first channel and the pressure inside the buffer reservoir. The resulting pressure equalization also affects the supply chamber, preferably from the outside. Thanks to the supply fluid connection, a pressure equalization is created between the pressure in the supply chamber and the pressure in the second channel. This also creates a pressure equalization between the pressure in the first channel and the pressure in the second channel.

[0028] The buffer reservoir with the supply chamber pneumatically decouples the second source from the second channel, largely independent of the pressure and volume flow at which the second source provides the second gas component. The second source can provide the second gas component at a time-constant or time-varying pressure and volume flow. Therefore, the buffer reservoir avoids the need to control or regulate the pressure or volume flow at which the second source provides the second gas component. This makes it easier to use an existing or currently available second source to provide the gas mixture to the patient-side coupling unit. This effect is particularly advantageous when the second source is a mobile or other source that is difficult or impossible to regulate or control.This effect is often also advantageous when a stationary supply network supplies various supply arrangements according to the invention with the second gas component. The supply arrangements connected to the supply network may require the second gas component at different pressures.

[0029] Thanks to the pneumatic control line, it is possible, but not necessary, to design the buffer storage in such a way that an electronic control unit controls the buffer storage based on measured values ​​from a pressure sensor. Rather, in many cases, the buffer storage can be designed as a purely mechanical component. In this case, the buffer storage requires no electrical power or data connection. In many cases, such a buffer storage is mechanically more stable and / or more robust against environmental influences than an electronically controlled buffer storage.

[0030] It is possible for a signal-processing electronic control unit to receive and process measured values ​​from a pressure sensor, with this pressure sensor measuring a measure of the pressure in the first channel. According to one embodiment, the control unit controls the buffer storage depending on measured values ​​from the pressure sensor, with the goal of the control being that the pressure inside the buffer storage, particularly in the supply chamber, follows the pressure in the first channel. Thanks to the supply fluid connection, the pressure in the second channel then also follows the pressure in the first channel.

[0031] It is also possible for the pressure sensor(s) to measure the pressure downstream of the mixing point, i.e., in the inspiratory channel. Again, according to one embodiment, the control unit controls the buffer reservoir based on the measured values ​​of the pressure sensor. The goal of this control is for the pressure inside the buffer reservoir to follow the pressure in the inspiratory channel. Thanks to the control fluid connection and the supply fluid connection, the pressure in the first channel and the pressure in the second channel then also follow the pressure in the inspiratory channel.

[0032] Instead of a pressure sensor or in addition to the pressure sensor, a sensor for the volume flow through the respective channel can also be used.

[0033] According to the invention, the buffer storage device comprises a housing and a fluid-tight separating element. The housing is preferably rigid. The separating element is arranged inside the housing and is preferably attached to the inside of the housing. The separating element divides the interior of the housing in a fluid-tight manner into two different chambers, namely the supply chamber and a control chamber. Thanks to the separating element, fluid is prevented from passing from one chamber to the other. The separating element is preferably designed such that the volume of the supply chamber is variable, even if the housing is rigid.

[0034] It's possible that the two chambers together occupy the entire interior of the housing. It's also possible that part of the buffer tank belongs to neither the supply chamber nor the control chamber. The term "fluid-tight" is not necessarily absolute, but can include the possibility that a relatively small amount of fluid can pass from one chamber to the other through unavoidable leaks.

[0035] The fluid connection between the buffer reservoir and the second source connects the supply chamber inside the housing at least temporarily with the second source, i.e. with the source for the second gas component. The supply fluid connection between the buffer reservoir and the second channel connects the supply chamber to the second channel. Thanks to this design, the second source is in fluid communication with the second channel, with this fluid connection passing through the supply chamber. The supply fluid connection effects pressure equalization between the pressure in the supply chamber and the pressure in the second channel. Because the separating element separates the two chambers from each other in a fluid-tight manner, the second gas component is prevented from passing through the pneumatic control line into the first channel.

[0036] The pneumatic control line and thus the control fluid connection connect the control chamber inside the housing to the first channel. This establishes a fluid connection between the first channel and the control chamber, which fluid connection is part of the control fluid connection according to the invention. The pneumatic control line effects pressure equalization between the pressure in the first channel and the pressure in the control chamber.

[0037] According to one embodiment of this design, the separating element is flexible. According to another embodiment, the separating element is rigid and arranged so that it can move relative to the housing, for example, it is mounted so that it can be displaced or pivoted. For example, the separating element is a displaceably mounted rigid plate.

[0038] In both implementations, at least one section of the separating element can change its position relative to the buffer tank housing. This change is caused in particular by a difference in pressure between the two chambers and reduces the pressure difference. Ideally, the flexible separating element completely eliminates any pressure difference between the two chambers.

[0039] Because the separating element inside the housing is flexible and / or movable, pressure equalization occurs automatically between the pressure in the supply chamber and the pressure in the control chamber. After the pressure in one chamber has changed, it usually takes some time until the pressure in the other chamber has changed accordingly. This pressure equalization takes place automatically, without the need for any control or external intervention. Instead, the separating element can be a passive mechanical component. This pressure equalization causes pressure equalization between the pressure in the first channel and the pressure in the second channel via the chain of effects described above.

[0040] According to the invention, the pneumatic control line connects the buffer reservoir to the first channel. This feature can be combined with a design in which the buffer reservoir is electronically controlled. This combination creates redundancy and, in some cases, allows the pressures in the two chambers to equalize even more quickly.

[0041] Preferably, the supply chamber is large enough to contain and release at least one tidal volume. Tidal volume is the volume an adult patient takes in with a single breath. Thanks to this design, the supply chamber can provide a quantity of the second gas component sufficient for a single ventilation stroke at any desired mixture ratio.

[0042] According to the invention, the separating element is designed as a flexible, fluid-tight bag or comprises a flexible, fluid-tight bag. A gap is formed between the housing and the bag, at least in some areas, forming an interior space. This interior space at least partially encloses the bag. The housing surrounds and protects the bag. The separating element separates the interior space from the interior of the bag. The interior of the bag forms one chamber, and the interior space in the housing around the bag forms another chamber.

[0043] In a first alternative of the invention, the control chamber is formed in the interior space between the housing and the bag. The pneumatic control line establishes the control fluid connection, which connects the interior space between the bag and the housing to the first channel. The supply chamber is arranged inside the bag and is enclosed by the bag. The supply fluid connection connects the interior of the bag to the second channel.

[0044] In a second alternative of the invention, the control chamber is formed inside the bag. The pneumatic control line establishes the control fluid connection between the interior of the bag and the first channel. The supply chamber is formed in the interior space between the housing and the bag. The supply fluid connection connects this interior space to the second channel.

[0045] Both alternatives of the invention make it possible in many cases to provide a particularly robust mechanical buffer storage. If the buffer storage is cuboid-shaped, it is often sufficient to connect the bag to one wall of this cuboid and to provide an opening in this wall through which the supply fluid connection is routed.

[0046] To ensure pressure equalization between the two channels, the second source must provide neither too much nor too little of the second gas component. Otherwise, the buffer storage tank will no longer be able to achieve the desired pressure equalization. Various designs are possible to monitor the buffer storage tank and, if necessary, trigger an automatic change or at least an alarm.

[0047] In one embodiment, the housing is transparent, or a viewing window is embedded in the housing. A user can visually monitor the buffer storage and in particular the position of the separating element from the outside. In particular, the undesirable situation that the actual position of the separating element deviates significantly from a position that occurs when pressure is equalized between the two chambers can be detected. If the separating element comprises a bag, both the undesirable event that the bag is heavily compressed (too little pressure in the bag / too much pressure in the interior between the bag and the housing) and the undesirable event that the bag is pressed against the inner wall of the housing (too much pressure in the bag / too little pressure in the interior) can be visually detected.

[0048] Another implementation eliminates the need to visually monitor the buffer storage. In one implementation of the design with the two chambers inside the buffer storage, the supply arrangement comprises a sensor arrangement. In one implementation, this sensor arrangement is capable of measuring a measure of a pressure difference, namely the difference between the pressure in the supply chamber and the pressure in the control chamber. If the measured pressure difference lies outside a predetermined range around zero for a sufficiently long period of time, a message is generated and preferably output in a form perceptible to a person. In another implementation, the sensor arrangement is capable of measuring a measure of the volume of the bag. For example, the sensor arrangement detects the undesirable event that the bag is pressed against the housing from the inside, which indicates that the bag is too large.

[0049] The implementation form with the transparent housing or the viewing window can be combined with the implementation form comprising the sensor arrangement.

[0050] One possible remedy is to at least temporarily change the pressure with which the second source is able to provide the second gas component.

[0051] According to the invention, the supply arrangement is capable of generating a gas mixture comprising a first gas component and a second gas component. The first gas component is provided by the first source, and the second gas component by the second source. In one embodiment, the supply arrangement is capable of generating a gas mixture that additionally comprises a third gas component, for example, an anesthetic. A third source provides the third gas component.

[0052] In another embodiment, both the second source and a further source are capable of providing the second gas component. This creates redundancy. The further source preferably provides the second gas component at a higher pressure than the second source. For example, the second source is a mobile source, in particular an oxygen generator, and the further source is a stationary supply connection or comprises a pressurized cylinder. Alternatively, the further source is capable of providing a third gas component.

[0053] In this application, the supply arrangement preferably additionally comprises a pneumatic pressure reducer with a pre-pressure inlet and a back-pressure outlet. Furthermore, the supply arrangement comprises a third channel for the second or third gas component. In one alternative, this third channel leads to the mixing point to which the first channel and the second channel also lead. In another alternative, the third channel leads to a further mixing point, which is in fluid communication with the mixing point and can be arranged upstream or downstream of the mixing point, in which the first and second gas components are mixed. The inspiration channel leads from the mixing point or from the further mixing point to the patient-side coupling unit.

[0054] A fluid connection is established or can be established between the upstream pressure inlet of the pressure reducer and the additional source, allowing the second or third gas component to be fed into the pressure reducer from the additional source. The downstream pressure outlet of the pressure reducer is connected to the third channel, allowing the pressure reducer to feed the second or third gas component into the third channel.

[0055] The pressure reducer provides the second or third gas component at its downstream pressure outlet. At least as a rule, the pressure at the downstream pressure outlet is lower than the pressure at the upstream pressure inlet, meaning the pressure reducer reduces the pressure. The pressure reducer is designed so that this provision at the downstream pressure outlet has the following effect: The temporal progression of the pressure at the downstream pressure outlet follows the temporal progression of the pressure at the supply connection element.

[0056] It is possible that a pressure sensor measures the pressure in the first channel and a signal-processing control unit controls the pressure reducer depending on a signal from the pressure sensor for the first channel.

[0057] It is possible that a signal processing control unit electronically controls the pressure reducer so that the pressure with which the pressure reducer provides the second gas component at the back pressure outlet follows the pressure in the first channel.

[0058] In another implementation of the pressure reducer, the pressure reducer also includes a control pressure input. The supply arrangement includes an additional pneumatic control line. The additional pneumatic control line establishes an additional pneumatic control fluid connection between the first channel and the control pressure input. The additional pneumatic control line eliminates the need for electronic control of the pressure reducer. Instead, it is possible to design the pressure reducer as a purely mechanical and pneumatic component. The two implementations, with electronic control and the additional pneumatic control line, can also be combined, creating redundancy.

[0059] The invention further relates to a system capable of supplying a patient-side coupling unit with a gas mixture. This gas mixture comprises a first gas component and a second gas component. The supply system comprises a first source, a second source, and a supply arrangement according to the invention. The first source provides the first gas component, and the second source provides the second gas component. A fluid connection is established, at least temporarily, between the supply connecting element of the first channel of the supply arrangement and the first source. A fluid connection is also established, at least temporarily, between the supply chamber in the buffer storage of the supply arrangement and the second source.

[0060] The advantages of the supply arrangement according to the invention just described also apply to this supply system. Possible advantageous embodiments of the supply arrangement according to the invention also represent advantages of the supply system.

[0061] In one embodiment, the supply system additionally comprises a further source, which is also capable of providing the second gas component, preferably at a higher pressure than the second source, or even a third gas component. The supply arrangement additionally comprises a pressure reducer. A pre-pressure inlet of the pressure reducer is fluidly connected to the further source, and a downstream pressure outlet of the pressure reducer is fluidly connected to the second channel. The pressure at the downstream pressure outlet follows the pressure in the first channel.

[0062] The invention further relates to a ventilation system capable of artificially ventilating a patient. This ventilation system comprises the aforementioned patient-side coupling unit, a fluid delivery unit, and a supply arrangement or supply system according to the invention. The fluid delivery unit is capable of delivering a gas mixture to the patient-side coupling unit, said gas mixture having been generated by the supply arrangement or supply system.

[0063] The fluid conveying unit can be located upstream or downstream of the mixing point.

[0064] The invention is described below using an exemplary embodiment. Figure 1 schematically shows how a patient-side coupling unit is supplied with a gas mixture of breathing air and pure oxygen, with two different sources providing the pure oxygen at different pressures; Figure 2 schematically shows a modification of the design of Figure 1 , wherein a single source provides the pure oxygen; Figure 3 shows an exemplary temporal course of the volume flow and the pressure in the inspiration channel; Figure 4 shows an exemplary coupling of a buffer storage device with a bag to the ventilator; Figure 5 shows another exemplary coupling of a buffer storage device with a bag to the ventilator; Figure 6 shows an exemplary coupling of a buffer storage device with a membrane to the ventilator.

[0065] In the exemplary embodiment, the invention is used to artificially ventilate a patient Pt. A patient-side coupling unit 9, for example a breathing mask, a tube, or a catheter, is attached to or in the body of the patient Pt.

[0066] A ventilator 100, shown only schematically, performs a sequence of ventilation strokes and, with each ventilation stroke, delivers a gas mixture to the patient-side coupling unit 9 and thus to the patient Pt. The supply arrangement according to the invention belongs to the ventilator 100. The gas mixture contains a proportion (vol%) of oxygen, with a user having specified a target value for this proportion. This oxygen proportion can be higher than the proportion of oxygen in the breathing air. To increase the proportion of oxygen compared to the breathing air, a gas mixture of breathing air and pure oxygen is generated in the exemplary embodiment. The gas mixture can additionally contain an anesthetic, so that the patient Pt is sedated or anesthetized.

[0067] A user specifies a desired oxygen content in the gas mixture. For example, the user manually adjusts the oxygen content using a rotary knob 30.

[0068] Figure 1shows a first embodiment of an arrangement for generating this gas mixture with a higher oxygen content and conveying it to the patient-side coupling unit 9. A first channel K.1 provides the breathing air. A second channel K.2 and a third channel K.3 provide pure oxygen. The second channel K.2 and the third channel K.3 flow into a mixing point 18. A fourth channel K.4, which also conveys pure oxygen, begins at the mixing point 18. The term "channel" refers to a fluid conveying unit capable of conveying a fluid along a trajectory.

[0069] The first channel K.1 and the fourth channel K.4 lead to a mixing point 8. From this mixing point 8, an inspiration channel K.30, for example a tube for inhalation and optionally a two-lumen tube with an additional tube for exhalation, leads to the patient-side coupling unit 9. This inspiration channel K.30 directs the mixture of air and pure oxygen to the patient-side coupling unit 9.

[0070] It is also possible for the gas mixture to contain a third gas component, for example, an anesthetic. In this configuration, a third channel (not shown) conveys the third gas component to mixing point 8.

[0071] A blower 2 or pump or other fluid conveying unit of the ventilator 100 draws in ambient air through an inlet E of the conveying unit 2 and feeds the drawn-in air into the first channel K.1.

[0072] A filter 23 is arranged between the inlet E and the fan 2. In the application according to Figure 1 Inlet E acts as the source for the first gas component.

[0073] A supply connection element V.1 of the first channel K.1 is connected to a supply outlet of the blower 2. The pressure in the first channel K.1 ideally follows a predetermined temporal progression, for example, it is constant over time. The pressure in the first channel K.1 is preferably always above the maximum ventilation pressure, i.e., above the maximum pressure at which the gas mixture is delivered to the patient-side coupling unit 9 and further into the lungs of the patient Pt, and is preferably between 20 mbar and 100 mbar.

[0074] The volume flow, i.e. the flow of gas per unit of time, through the inspiration channel K.30 to the patient-side coupling unit 9 should follow a predetermined time course. Figure 3The top shows an example of the required time course of the volume flow (Vol') and the bottom shows an example of the required time course of the pressure (P). Values ​​above the x-axis indicate a flow of the gas mixture toward the patient Pt (inhalation), while values ​​below indicate a flow away from the patient Pt (exhalation).

[0075] A signal-processing control unit 3 performs closed-loop control, with the actual volume flow Vol' being the controlled variable and the specified time profile of the volume flow being the reference variable. The actual volume flow Vol' to the patient-side coupling unit 9 is the sum of the volume flows through the two channels K.1 and K.4, which flow into the mixing point 8.

[0076] A volume flow sensor 6.1 measures the actual volume flow in the first channel K.1. For example, the volume flow sensor 6.1 measures a pressure difference between two measuring points in the first channel K.1 spaced apart in the flow direction. The control unit 3 controls a proportional valve 4.1 and thereby changes the volume flow through the first channel K.1 downstream of the proportional valve 4.1 to the mixing point 8, as needed.

[0077] A volume flow sensor 6.2 and a proportional valve 4.2 are located in the fourth channel K.4. These components function in the same way as the corresponding components in the first channel K.1. Control unit 3 controls proportional valve 4.2 with the goal of ensuring that the actual volume flow through the fourth channel K.4 follows a specified time profile.

[0078] As already explained, a gas mixture is delivered from mixing point 8 to the patient-side coupling unit 9. The actual volume flow Vol' of this gas mixture downstream from mixing point 8 should follow a predetermined time profile. Furthermore, an oxygen content in the gas mixture is specified, preferably as a vol%. This oxygen content can be constant or variable over time. The two proportional valves 4.1 and 4.2 can each change a volume flow, but not an oxygen content.

[0079] Pure oxygen flows through the fourth channel K.4, and breathing air through the first channel K.1. The required proportion of oxygen in the gas mixture and the known proportion of oxygen in air result in a required target ratio between the two volume flows through the two channels K.1 and K.4. The predetermined temporal profile of the volume flow to the patient-side coupling unit 9 and the target ratio of the volume flows result in a target profile for the volume flow in the first channel K.1 and a target profile for the volume flow in the fourth channel K.4. The control unit 3 or a higher-level control unit calculates these two target profiles for the two channels K.1 and K.4, and the control unit 3 controls the two proportional valves 4.1 and 4.2 depending on these two target profiles. The control unit 3 therefore carries out two volume flow controls, namely one in the first channel K.1 and one in the fourth channel K.4.

[0080] The second channel K.2 supplies pure oxygen at a lower pressure than the third channel K.3. In the illustrated embodiment, the second channel K.2 is connected via a connecting line 26 to a schematically shown and preferably mobile second source 25. A pressure relief valve 27 opens when the pressure in the connecting line 26 is above a predetermined limit of, for example, 100 mbar, thereby limiting the pressure in the connecting line 26.

[0081] In one embodiment, the second source 25 receives breathing air from the ambient air and absorbs a larger portion of the nitrogen from the breathing air through multiple pressure changes. The ambient air is stored under increased pressure in a first tank containing zeolites. There, a portion of the nitrogen is absorbed. The compressed gas with a reduced nitrogen content is fed into a subsequent second tank. In the first tank, the pressure drops, the air expands, the nitrogen is desabsorbed and flushed out as waste gas. This process is repeated several times until a sufficiently high oxygen concentration is reached. A source operating in this way can supply a gas mixture with a maximum of 95 vol% oxygen. Noble gases in the ambient air remain in this gas mixture. When calculating the target volume flows, the oxygen content of the gas mixture from the second source is taken into account.

[0082] It is also possible for the mobile source 25 to contain chemical substances, such as loose or solid substances, which undergo an exothermic chemical reaction upon activation, for example upon contact with moisture. In this reaction, the source 25 releases oxygen. The substance is, for example, sodium chlorate. The source comprises, for example, at least one chlorate candle. For example, the chemical reaction 2 NaClO 3 → 2 NaCl + 3 O 2 takes place in the mobile source 25. Typically, such a mobile source 25 is capable of delivering oxygen at a maximum pressure of 500 mbar.

[0083] The third channel K.3 receives pure oxygen (O2) from a supply line 21 connected to a supply connection 20. In the example shown, this supply connection 20 is stationary in a wall W and is supplied from a stationary hospital infrastructure. It is also possible for the third channel K.3 to receive pure oxygen from pressurized cylinders. The supply connection 20 preferably provides the pure oxygen at a pressure between 2 bar and 8 bar.

[0084] An optional check valve 29 in the supply line 21 prevents pure oxygen from being forced back into the supply connection 20 and into the hospital infrastructure.

[0085] A pneumatic pressure reducer 1 comprises a pre-pressure inlet V.3 and a back-pressure outlet V.2. The pre-pressure inlet V.3 is connected to the supply line 21, and the back-pressure outlet V.2 is connected to the second channel K.2. The pressure reducer 1 reduces the pressure of the pure oxygen provided by the supply connection 20. Preferably, the pneumatic pressure reducer 1 additionally comprises a control pressure inlet V.4.

[0086] In the illustrated embodiment, two sources provide pure oxygen independently of one another: supply connection 20 and the preferably mobile source 25. Thanks to this redundancy, pure oxygen is still available even if one of the two sources 20, 25 fails or is switched off. In the illustrated embodiment, the two sources 20, 25 are arranged outside the ventilator 100.

[0087] Figure 2 shows schematically a modification of the ventilator 100 of Figure 1 . The same reference symbols have the same meaning as in Figure 1 .

[0088] In this modification, the ventilator 100 has its own power supply unit 32, for example, a number of rechargeable batteries (accumulators), wherein the power supply unit 32 in particular drives the fan 2 and provides the electrical energy for the control unit 3, the sensors 6.1, 6.2, and the proportional valves 4.1, 4.2. The ventilator 100 is therefore independent of a stationary power supply network and is used, for example, for emergency care of a patient Pt, in particular on board a vehicle or aircraft or at the scene of an accident. In this embodiment, no stationary supply connection 20 is available. Therefore, no supply line 21, no pressure reducer 1, no third channel K.3, and no fourth channel K.4 are required. The second channel K.2 leads from the buffer tank 5 to the mixing point 8. The pure oxygen is provided exclusively by the source 25.

[0089] Unless otherwise stated, the following description refers to the design according to Figure 1 as well as the design according to Figure 2 .

[0090] The pressure in the first channel K.1 can vary over time, even in the section between the supply connection element V.1 and the proportional valve 4.1. In the exemplary embodiment, both the pressure in the second channel K.2 and in the embodiment according to Figure 1The pressure in the third channel K.3 follows the pressure in the first channel K.1, ideally without a time delay. The stationary supply connection 20 provides pure oxygen at a pressure that is ideally constant over time. The preferably mobile source 25 also provides pure oxygen, but at a pressure that can vary over time, whereby the temporal progression of the pressure in the connecting line 26 is generally not synchronized with the pressure in the first channel K.1 and depends, for example, on processes in the source 25. The invention eliminates the need to synchronize the mobile source 25 with the pressure in the first channel K.1 or with the ventilation strokes.

[0091] In the following, we first describe how the temporal progression of the pressure in the second channel K.2 follows the temporal progression of the pressure in the first channel K.1. Figure 1 and Figure 2As can be seen, a buffer reservoir 5 is arranged between the outlet of the connecting line 26 and the inlet of the second channel K.2. The terms "inlet" and "outlet" refer to the flow direction of the oxygen to the mixing point 18 and 8, respectively. In the exemplary embodiment, this buffer reservoir 5 is arranged outside the ventilator 100 and can be detachably connected to the ventilator 100. It can also be a component of the ventilator 100.

[0092] The buffer storage tank 5 comprises a rigid housing 10 and a flexible, fluid-tight separating element 7, 7.1, which is arranged entirely inside the housing 10. The separating element 7, 7.1 divides the interior of the housing 10 into two fluid-tight chambers, namely a supply chamber In.O2 and a control chamber In.K1. Both chambers In.O2, In.K1 are fluid-tightly sealed from the environment, which is facilitated by the housing 10.

[0093] The connecting line 26 is guided through an inlet-side opening in the housing 10, and the second channel K.2 through an outlet-side opening in the housing 10. The supply chamber In.O2 is fluidly connected to the connecting line 26 on the inlet side and has a supply fluid connection with the second channel K.2 on the outlet side. Preferably, the connecting line 26 and the second channel K.2 are or can be connected to the housing 10 in a fluid-tight manner. In one embodiment, the supply fluid connection is established through an opening in the housing 10, with the second channel K.2 being fluid-tightly connected to this opening.

[0094] A pneumatic control line 28 is mechanically connected to the housing 10 and establishes a control fluid connection between that section of the first channel K.1 which leads from the supply connecting element V.1 to the proportional valve 4.1 and the control chamber In.K1.

[0095] Thanks to the pneumatic control line 28, the pressure in the control chamber In.K1 follows the time-varying pressure in the first channel K.1. Because the separating element 7, 7.1 is fluid-tight and flexible, the pressure in the supply chamber In.O2 follows the time-varying pressure in the control chamber In.K1, at least as long as the pressures in the two chambers In.O2, In.K1 do not differ from each other by more than a design-related limit. Conversely, the pressure in the supply chamber In.O2 can have a feedback effect on the pressure in the first channel K.1 via the interior space In.K1 and the control line 28. Ideally, the pressure in the first channel K.1, the pressure in the pneumatic control line 28, in the control chamber In.K1, the pressure in the supply chamber In.O2 and the pressure in the second channel K.2 have the same time course. In practice, unavoidable delays occur, among other things because of unavoidable leaks and sometimes also turbulence.In addition, the two chambers In.O2, In.K1 in the housing 10 necessarily only have a certain volume each and can only compensate pressure differences to a certain degree.

[0096] In the design according to Figure 1A further pneumatic control line 28.1 establishes a further control fluid connection between the first channel K.1 and the control pressure inlet of the pressure reducer 1. In a first implementation, this further pneumatic control line 28.1 is connected directly to the first channel K.1, and in a second implementation, to the pneumatic control line 28. Thanks to this further pneumatic control line 28.1, the pressure at the back pressure outlet V.2 of the pressure reducer 1 follows the pressure in the first channel K.1. Thanks to the further pneumatic control line 28.1, it is not necessary for the control unit 3 to control the pressure reducer 1 or the source 20. Rather, the pressure reducer 1 can be designed as a purely pneumatic and mechanical component.

[0097] In the form of realization that Figure 1 , Figure 2 , Figure 4 and Figure 5As shown, this separating element 7, 7.1 is designed as a flexible bag 7. In another embodiment, the separating element 7, 7.1 is designed as a membrane 7.1, cf. Figure 6 The following description refers to a bag 7 as the separating element. In the described embodiment, the supply chamber In.O2 is formed inside the bag 7, and the control chamber In.K1 is formed in the area inside the housing 10 and outside the bag 7. The control chamber In.K1 preferably completely surrounds the bag 7. The bag 7 prevents fluid communication between the source 25 and the first channel K.1.

[0098] If the pressure at which the second source 25 feeds pure oxygen into the connecting line 26 is currently greater than the pressure in the bag 7, the bag 7 is expanded and thus stretched against the pressure in the control chamber In.K1. Conversely, the pressure in the control chamber In.K1 compresses the bag 7 if the pressure of the source 25 is currently lower than the pressure in the control chamber In.K1.

[0099] Two adverse events may occur but should be avoided as much as possible: Source 25 is supplying too little pure oxygen to bag 7 (too low a volume flow). As a result, the pressure in control chamber In.K1 completely compresses bag 7. Source 25 is supplying too much pure oxygen to bag 7 (too high a volume flow). As a result, bag 7 is greatly expanded against the pressure in control chamber In.K1 and is pressed against housing 10 from the inside.

[0100] In one embodiment, the housing 10 is transparent, or a window is embedded in the housing 10. A user can visually inspect the bag 7 from the outside and, in particular, determine whether the bag 7 is completely compressed or pressed against the housing 10 from the inside.

[0101] In another implementation, a sensor, such as a contact switch, can detect the undesired event and report that the bag 7 is pressed against the housing 10 from the inside. Furthermore, in one embodiment, the volume flow sensor 6.2 generates a report if the volume flow through the second channel K.2 is too low. Such an excessive volume flow can be caused by the source 25 providing too little pure oxygen.

[0102] In a further implementation, a pressure sensor 16.1 measures the pressure in the pneumatic control line 28. This pressure ideally corresponds to the pressure in the control chamber In.K1. Another pressure sensor 16.2 measures the pressure in the second channel K.2. This pressure ideally corresponds to the pressure in the supply chamber In.O2. If the difference between the pressure in the control chamber In.K1 and the pressure in the supply chamber In.O2 is above a predetermined upper limit, the undesirable event may have occurred that the bag 7 is pressed against the inside of the housing 10. If this pressure difference is below a predetermined lower limit, the undesirable event may have occurred that the bag 7 is strongly or even completely compressed. If one of these events has occurred, a message is preferably generated and output in a form that can be perceived by a person.

[0103] In one embodiment, the buffer storage 5 is a component of the ventilator 100. In another embodiment, the buffer storage 5 can be detachably connected to the ventilator 100. Figure 4 and Figure 5 show two possible implementations of how the buffer storage 5 is detachably connected to the ventilator 100 from the outside. The same reference numerals have the same meaning as in Figure 1 and Figure 2 .

[0104] In the implementation form according to Figure 4 A section of the second channel K.2 is routed coaxially through the interior of a section of the pneumatic control line 28. Therefore, the buffer reservoir 5 can be connected to the ventilator 100 at a single pneumatic coupling point. It is also possible for the section of the pneumatic control line 28 to be routed through the interior of the section of the second channel K.2.

[0105] In the implementation form according to Figure 5Two spatially spaced pneumatic coupling points are provided between the buffer reservoir 5 and the ventilator 100, namely a first coupling point for the second channel K.2 and a second coupling point for the pneumatic control line 28. These two coupling points are preferably mechanically different from each other, so that a mechanical coding is provided. This mechanical coding prevents the buffer reservoir 5 from being incorrectly connected to the ventilator 100.

[0106] In the implementation just described, the supply chamber In.O2 is formed inside the bag 7, and the control chamber In.K1 surrounds the bag 7. It is also possible that, conversely, the control chamber In.K1 is formed inside the bag 7 and the supply chamber In.O2 surrounds the bag 7.

[0107] Figure 6shows an alternative design of the separating element. Instead of a bag 7, a flexible membrane 7.1 is attached inside the housing 10. This membrane 7.1 divides the interior of the housing 10 into the supply chamber In.O2 (in Figure 6 below) and the control chamber In.K1 (in Figure 6 (top). The dashed lines indicate two possible upward and downward deflections of diaphragm 7.1. It is also possible that the supply chamber In.O2 is at the top and the control chamber In.K1 is at the bottom. List of reference symbols

[0108] 1 pneumatic pressure reducer in the second channel K.2, includes the pre-pressure inlet V.3, the back-pressure outlet V.2 and the control pressure inlet V.4 2 Blower of the ventilator 100, is connected via a supply output to the first channel K.1, connected to the inlet E, acts as the first source 3 signal processing control unit, receives measured values ​​from the volume flow sensors 6.1 and 6.2, controls the proportional valves 4.1 and 4.2 4.1 Proportional valve in the first channel K.1, capable of changing the volume flow through the first channel K.1, controlled by control unit 3 4.2 Proportional valve in the fourth channel K.4 or in the second channel K.2, capable of changing the volume flow through the fourth channel K.4 or the second channel K.2, controlled by the control unit 3 5 Buffer storage, comprises the bag 7 and the housing 10, forms the control chamber In.K1 and the supply chamber In.O2 inside the housing 10 6.1 Volume flow sensor, measures a measure of the volume flow through the first channel K.1 6.2 Volume flow sensor, measures a measure of the volume flow through the fourth channel K.4 or the second channel K.2 7 flexible bag inside the buffer tank 5, surrounded by the control chamber In.K1, surrounds the supply chamber In.O2, connected to the lines 26 and 28 7.1 flexible membrane inside the buffer tank 5, separates the supply chamber In.O2 from the control chamber In.K1 8 Mixing point into which the two channels K.1 and K.3 or K.2 flow 9 patient-side coupling unit, connected to the inspiration channel K.30 10 rigid housing of the buffer tank 5 16.1 Pressure sensor, measures the pressure in the pneumatic control line 28 16.2 Pressure sensor, measures the pressure in the second channel K.2 18 Mixing point where the second channel K.2 flows into the third channel K.3 and where the inspiration channel K.30 begins 20 stationary supply connection in the wall W for pure oxygen, connected to the third channel K.3, acts as an additional source 21 Supply line, leads from supply connection 20 to pre-pressure chamber Ka.1 in pressure reducer 1 23 Filter behind inlet E 25 mobile source of pure oxygen, connected to the second channel K.2, acts as a second source 26 Connecting line from mobile source 25 to buffer storage 5 27 Pressure relief valve in the connecting line 26 28 pneumatic control line, connects the control chamber In.K1 with the first channel K.1 28.1 additional pneumatic control line, connects the first channel K.1 with the control pressure input V.4 29 Check valve in the supply line 21 30 Rotary knob that a user can turn to specify the required proportion of oxygen in the gas mixture that is delivered to the patient-side coupling unit 9 32 Ventilator power supply unit 100 100 Ventilator, generates a gas mixture of breathing air and pure oxygen, ventilates the patient Pt artificially, comprises the supply arrangement according to the invention E Inlet for ambient air, acts as the first source, connected to the fan 2 In.K1 Control chamber inside the housing 10, is in control fluid connection with the first channel K.1 via the control line 28, surrounds the bag 7 in one embodiment In.O2 Supply chamber inside the housing 10, is in fluid communication with the connecting line 26 and in a supply fluid connection with the second channel K.2 K.1 first channel, provides breathing air, which the blower 2 conveys K.2 second channel, provides pure oxygen at a lower pressure from source 25 K.3 third channel, provides pure oxygen at a higher pressure from the supply port 20, leads to the mixing point 18 K.4 fourth channel, carries pure oxygen from mixing point 18 to mixing point 8 K.30 Inspiration channel, directs the gas mixture from the mixing point 8 to the patient-side coupling unit 9 P Pressure, especially through the inspiration channel K.30 to the patient-side coupling unit 9 Pt Patient, is artificially ventilated by the ventilator 100, wears the patient-side coupling unit 9 V.1 Supply connector of the first channel K.1, connected to a supply outlet of the fan 2 V.2 Back pressure outlet of pressure reducer 1, connected to the second channel K.2 V.3 Pre-pressure inlet of pressure reducer 1, connected to supply line 21 V.4 Control pressure input of pressure reducer 1, connected to the further pneumatic control line 28.1 Vol' Volume flow through the inspiration channel K.30 to the patient-side coupling unit 9 W Wall, has supply connection 20 for pure oxygen

Claims

1. Supply arrangement for supplying a patient-side coupling unit (9) with a gas mixture comprising a first gas component (air) and a second gas component (O2), the patient-side coupling unit (9) being connected or connectable to a patient (Pt), the supply arrangement comprising - a first channel (K.1) comprising a supply connection element (V.1), - a second channel (K.2), - a mixing point (8), - an inspiratory channel (K.30), - a buffer tank (5) and - a pneumatic control line (28), the buffer tank (5) comprising a housing (10) and a fluid-tight separating element (7, 7.1) in the interior of the housing (10), the separating element (7, 7.1) dividing the interior of the housing (10) in a fluid-tight manner into a supply chamber (In.O2) and a control chamber (In.K1), a fluid connection being established or establishable between the supply connection element (V.1) and a first source (E), namely a source of the first gas component (air), a fluid connection (26) being established or establishable between the supply chamber (In.O2) and a second source (25), namely a source of the second gas component (O2), a supply fluid connection being established or establishable between the supply chamber (In.O2) and the second channel (K.2), the first channel (K.1) being configured to conduct the first gas component (air) from the supply connection element (V.1) to the mixing point (8), the second channel (K.2) being configured to conduct the second gas component (O2) from the supply chamber (In.O2) to the mixing point (8), the inspiratory channel (K.30) being configured to conduct a gas mixture generated in the mixing point (8) to the patient-side coupling unit (9), the pneumatic control line (28) establishing a control fluid connection between the first channel (K.1) and the buffer tank (5), the control fluid connection which the control line (28) establishes - connecting the control chamber (In.K1) with the first channel (K.1) and - effecting a pressure equalization between the control chamber (In.K1) and the first channel (K.1), and the supply arrangement being configured such that the buffer tank (5), the supply fluid connection and the control fluid connection effect a pressure equalization between - the pressure in the supply chamber (In.O2), - the pressure in the first channel (K.1) and - the pressure in the second channel (K.2), characterized in that the separating element (7, 7.1) is configured as a flexible bag (7) or comprises a flexible bag (7), an interior space being formed between the housing (10) and the bag (7), which interior space surrounds the bag (7), - the supply chamber (In.O2) being formed in the interior of the bag (7) and the control chamber (In.K1) being formed in the space between the housing (10) and the bag (7) or - the control chamber (In.K1) being formed in the interior of the bag (7) and the supply chamber (In.O2) being formed in the space between the housing (10) and the bag (7).

2. Supply arrangement according to claim 1, characterized in that the supply chamber (In.O2) is formed in the interior of the bag (7) and - both the fluid connection (26) between the supply chamber (In.O2) and the second source (25) - and the supply fluid connection are passed through the housing (10).

3. Supply arrangement according to any of the preceding claims, characterized in that the supply arrangement comprises a sensor arrangement (16.1, 16.2), the sensor arrangement (16.1, 16.2) being configured to measure the difference between - the pressure in the supply chamber (In.O2) and - the pressure in the control chamber (In.K1), and the supply arrangement being configured to generate a message if the measured pressure difference is outside a predetermined range.

4. Supply arrangement according to any of the preceding claims, characterized in that the supply arrangement comprises - a third channel (K.3) and - a pressure regulator (1) comprising an upstream pressure inlet (V.3) and a downstream pressure outlet (V.2), a fluid connection (21) being established or establishable between the upstream pressure inlet (V.3) of the pressure regulator (1) and a further source (20) of the second gas component (O2) or a source of a third gas component, the downstream pressure outlet (V.2) of the pressure regulator (1) being connected to the third channel (K.3), the third channel (K.3) being configured to conduct the second gas component (O2) or the third gas component from the downstream pressure outlet (V.2) to the mixing point (8) or to a further mixing point (18), the further mixing point (18) being in a fluid connection (Ka.2) with the mixing point (8) and / or with the patient-side coupling unit (9), and the pressure regulator (1) being configured to provide the second gas component (O2) in such a way that the variation over time of the pressure at the downstream pressure outlet (V.2) follows the variation over time of the pressure in the first channel (K.1) and / or the variation over time of the pressure in the second channel (K.2).

5. Supply arrangement according to claim 4, characterized in that the supply arrangement comprises a further pneumatic control line (28.1) and the pressure regulator (1) comprises a control pressure inlet (V.4), the further pneumatic control line (28.1) establishing a further control fluid connection between the first channel (K.1) and the control pressure inlet (V.4).

6. Supply system for supplying a patient-side coupling unit (9) with a gas mixture comprising a first gas component (air) and a second gas component (O2), the supply system comprising - a first source (E), - a second source (20) and - a supply arrangement according to any of the preceding claims, the first source (E) being configured to provide the first gas component (air), the second source (25) being configured to provide the second gas component (O2), a fluid connection being at least temporarily established between the supply connection element (V.1) of the supply arrangement and the first source (E), and a fluid connection (26) being at least temporarily established between the supply chamber (In.O2) and the second source (25) of the second gas component (O2).

7. Supply system according to claim 6, characterized in that the supply system comprises a further source (20) of the second gas component (O2) or of a third gas component and the supply arrangement is configured according to claim 4 or claim 5, a fluid connection (21) being at least temporarily established between the upstream pressure inlet (V.3) of the pressure regulator (1) and the further source (20).

8. Supply system according to claim 7, characterized in that the further source (20) provides the second gas component (O2) at a higher pressure than the second source (25).

9. Ventilation system (100) for artificial ventilation of a patient (Pt), the ventilation system (100) comprising - a patient-side coupling unit (9), - a fluid conveying unit (2) and - a supply arrangement according to any of claims 1 to 5 or a supply system according to any of claims 6 to 8, the patient-side coupling unit (9) being connected or connectable to a patient (Pt) and the fluid conveying unit (2) being configured to convey a gas mixture generated by the supply arrangement to the patient-side coupling unit (9).