Vaporising device for providing a breathing gas mixture

Abstract

The invention relates to a vaporising device for providing a breathing gas mixture, wherein the vaporising device comprises: a channel having an inner surface; a breathing gas inlet for introducing a breathing gas into the channel; an anaesthetic agent inlet for introducing an anaesthetic agent in liquid form into the channel; an outlet for discharging the breathing gas mixture from the channel, wherein the discharged breathing gas mixture comprises the breathing gas and the anaesthetic agent in vaporised form; wherein the inner surface comprises a vaporisation section for vaporising the anaesthetic agent, wherein the vaporising device is designed such that the anaesthetic agent introduced into the channel is directed onto a sub-section of the vaporisation section, wherein the vaporisation section comprises a surface which is designed to distribute the anaesthetic agent, which is directed onto the sub-section, from the sub-section across the remaining vaporisation section.

Description

[0001] Evaporation device for providing a breathing gas mixture

[0002] Technical area

[0003] The invention relates to an evaporation device for providing a breathing gas mixture. Furthermore, the invention relates to a ventilator. Furthermore, the invention relates to a method for providing a breathing gas mixture.

[0004] State of the art

[0005] Devices for artificial ventilation, which can also be used to anesthetize patients, are typically designed so that the respiratory gases are fed into a circuit. For this purpose, used gases such as oxygen (O2) are added to the circuit and carbon dioxide (CO2) is removed. In such a circuit, anesthetics, such as volatile anesthetics, can be added and removed in a controlled manner.

[0006] The administration of anesthetics is typically performed by enriching a breathing gas with gaseous anesthetics, then feeding the resulting breathing gas mixture into the anesthesia machine and delivering it to the patient via the breathing circuit. Gaseous dosing of anesthetics is simple to perform, but the dosage can sometimes be imprecise and inflexible.

[0007] Disclosure of the invention

[0008] One object of the present invention can be seen in providing an improved device for providing a breathing gas mixture. Another object of the invention can be seen in providing a correspondingly improved ventilator. Another object of the invention can be seen in providing a method for providing a breathing gas mixture.

[0009] These objects are achieved by the subject matter of the independent claims, namely with a device according to claim 1 and with a ventilator according to claim 20 and a method according to claim 21.

[0010] Further developments and advantageous embodiments of the invention are the subject of the dependent claims. The dependent claims relate to various independent, advantageous developments and embodiments of the present invention, the features of which can be freely combined with one another by a person skilled in the art within the scope of what is technically reasonable. This applies in particular beyond the boundaries of the various claim categories. The description further characterizes and specifies the invention, particularly in conjunction with the figures. A first aspect of the invention relates to an evaporation device for providing a breathing gas mixture.The evaporation device comprises: a channel having an inner surface; a breathing gas inlet for introducing a breathing gas into the channel; an anesthetic inlet for introducing an anesthetic in the liquid state into the channel; an outlet for discharging the breathing gas mixture from the channel; wherein the discharged breathing gas mixture comprises the breathing gas and the anesthetic in the vaporized state.

[0011] The inner surface comprises an evaporation section for evaporating the anesthetic. The evaporation device is designed such that the anesthetic introduced into the channel is directed to a partial section of the evaporation section, wherein the evaporation section comprises a surface designed to distribute the anesthetic directed to the partial section from the partial section into the remaining evaporation section. In some embodiments, the evaporation section can be designed to distribute the anesthetic evenly from the partial section into the remaining evaporation section to enable uniform evaporation of the anesthetic. A "uniform distribution" can be understood as the anesthetic being distributed over a surface in such a way that it is (ideally) evenly wetted and that an (ideally) equal amount of liquid is present at every point on the surface.It goes without saying that (minor) deviations from the ideal case may occur.

[0012] Various embodiments of the invention are described below. These embodiments are not intended to limit the scope of the invention.

[0013] "Breathing gas" can be understood as a gas or gas mixture that is inhaled and / or exhaled. The breathing gas can be, for example, normal breathing air from the environment, (pure) oxygen, or oxygen-enriched breathing air.

[0014] A "breathing gas mixture" can be understood as an inhaled and / or exhaled gas mixture that is enriched with at least one anesthetic. The breathing gas mixture can therefore also be referred to as an anesthetic gas (mixture). The breathing gas mixture can therefore contain the breathing gas and the anesthetic.

[0015] A "duct" can be understood as a three-dimensional space. A duct can be understood, for example, as an (elongated) pipe, a hose, or a combination of both. However, a duct can also be understood as a three-dimensional space that is not elongated. The duct can also have the shape of a cube, cuboid, pyramid, cylinder, cone, sphere, hemisphere, or the like. The duct has a rigid, flexible, or partially flexible duct wall. The duct can have different cross-sectional shapes. Depending on the shape of the duct wall, the duct can have a round, oval, angular, or square cross-section. A combination of round and angular wall elements is also possible. It can be advantageous for the duct to have an angular cross-section with a base section, two side sections, and a ceiling section.The channel can be made at least partially of a castable and / or thermally conductive material. The channel can be made at least partially of a metal and / or a polymer material (plastic).

[0016] In some embodiments, the channel or channel wall can be formed as a single piece. In a preferred embodiment, the channel or channel wall can be formed as multiple parts, for example, as two parts. It can be advantageous if the channel is formed from a base part and a cover part and is designed to be detachable. This can facilitate both the manufacture and cleaning of the device.

[0017] The inner surface of the channel wall encloses the channel's lumen. The breathing gas or breathing gas mixture can be absorbed and directed into the channel's lumen.

[0018] The channel has a length, a height, and a width. In relation to a coordinate system, the length or longitudinal direction can be understood as the x-axis, the height or vertical direction as the y-axis, and the width or transverse direction as the z-axis. The length can be many times greater than the width and / or the height, thus representing an elongated channel. The longitudinal direction (x-direction) can thus be many times greater than the transverse direction (z-direction) and / or the vertical direction (y-direction) of the channel. The height and width of the channel can be the same or different from one another. In some embodiments, the evaporation device and / or the channel can also be circular or oval. The channel comprises a breathing gas inlet and an outlet. The channel can be hermetically connected to other channels, lines, or other components of a ventilator or system via the breathing gas inlet and outlet.The breathing gas inlet and outlet can thus serve as connections through which the device can be hermetically connected to other components. The breathing gas inlet is designed to introduce a breathing gas into the channel. The outlet is designed to discharge a breathing gas and / or a breathing gas mixture from the channel. The evaporation device can thus be integrated into the breathing gas supply and / or the breathing gas circuit of a ventilator.

[0019] An "anesthetic" can be understood as a substance with which a patient's consciousness and / or sensation of pain and / or muscles can be influenced and / or deactivated. The patient can be anesthetized with the anesthetic.

[0020] The anesthetic can, for example, be an anesthetic gas such as nitrous oxide (N2O). The anesthetic can also be a volatile anesthetic. Volatile anesthetics can be selected from the group: isoflurane, sevoflurane, desflurane, halothane, enflurane, and methoxyflurane. Volatile anesthetics are characterized by their volatile nature and evaporate (rapidly) under normal atmospheric pressure.

[0021] The term "anesthetic inlet" can be understood as a device through which the anesthetic can be introduced into the channel. The anesthetic inlet is designed to introduce the anesthetic into the channel in liquid form. In some embodiments, the anesthetic inlet can also be designed to introduce anesthetic into the channel in gaseous form. As a rule, the breathing gas inlet and the anesthetic inlet represent two different entrances for introducing breathing gas or anesthetic into the channel. In some embodiments, however, it is also conceivable for breathing gas and anesthetic to be introduced into the channel via a single, common inlet.

[0022] Liquid anesthetic delivery into the canal offers the advantage of precise and economical dosing. With liquid dosing, the anesthetic can be delivered undiluted. This allows for anesthetic dosing to be independent of the supply of other respiratory gases such as fresh air or oxygen.

[0023] The anesthetic agents can be provided in a storage container, such as a tank or the like. A pressure can be present in the storage containers. The pressure can, in particular, be above normal atmospheric pressure. The pressure in the tanks can, for example, be at least 100 kPa, preferably at least 180 kPa.

[0024] The tanks can be connected to the anesthetic inlet. The anesthetic inlet can also be configured to keep the anesthetic under pressure so that the anesthetic retains its liquid state until it is introduced into the channel. A (partial) gaseous introduction can also occur. The introduction can be effected, for example, by means of a pump from the reservoir into the evaporation device.

[0025] The pressure in the channel may be lower than in the anesthetic inlet, allowing the anesthetic to evaporate. This allows the anesthetic in the channel to change from a liquid to a gaseous state and mix with the breathing gas to create the breathing gas mixture.

[0026] To enable uniform evaporation of the anesthetic, the inner surface of the channel features an evaporation section. The "evaporation section" can be understood as a section over which the liquid anesthetic is evenly distributed, allowing it to evaporate evenly. For this purpose, the evaporation section comprises a surface that can be designed to positively influence the distribution and / or evaporation of the anesthetic.

[0027] "Uniform distribution" can be understood as the ability of the anesthetic to spread over a large area in a short period of time and to wet it evenly, so that an approximately equal amount of fluid is present at every point on the surface. Uniform distribution eliminates the formation of deposits or puddles. Since the anesthetic thus has a large surface area with a constant (low) fluid level, the fluid can evaporate evenly and thus optimally and in a controlled manner.

[0028] The evaporation device is designed to achieve anesthetic flow rates over a very wide range. Very low to very high anesthetic flow rates are possible, namely in a range of approximately 5 pL to 10 mL of (liquid) anesthetic per minute.

[0029] A very high anesthetic flow rate of up to 10 mL per minute may be required if a patient needs to be anesthetized very quickly. If the patient has not been previously administered anesthetic, they are "unsaturated" with respect to anesthetic, and a large volume of anesthetic is needed to quickly and safely induce anesthesia. 10 mL of liquid anesthetic per minute corresponds to approximately 2 liters of breathing gas mixture that can be delivered to the patient per minute.

[0030] A very low anesthetic flow rate of 5 pL per minute or less may be required if the anesthesia has been ongoing for a longer period and the patient is already saturated with anesthetic and / or has a low metabolic rate. In such cases, a very low anesthetic flow rate is sufficient to maintain anesthesia. 5 pL of liquid anesthetic per minute corresponds to approximately 1 mL of breathing gas mixture that can be delivered to the patient per minute.

[0031] Advantageously, the device can comprise and / or be connected to a respiratory gas drive (e.g., a blower) to convey the respiratory gas through the evaporation section. This allows a high gas flow to be generated over the evaporation section even with small respiratory gas flows (fresh gas flows). This offers the advantage that the evaporation section can be kept relatively small while still achieving a good evaporation rate. A particular advantage is that this would also work with manual ventilation with appropriate control of the blower.

[0032] To force evaporation, the device can be designed such that the respiratory gas is moved over the evaporation section. For example, the entire respiratory gas flow going to the patient can be directed over the evaporation section or over the anesthetic. In some embodiments, it can also be provided that only a portion of the respiratory gas flow is directed over the evaporation section or over the anesthetic. For example, the evaporation device can be arranged on or in a bypass of the respiratory gas line of a ventilator.

[0033] According to one embodiment, the evaporation section can be formed as a surface with a length and a width, wherein the surface can be flat or curved in its transverse direction. According to a preferred embodiment, the surface can be flat. The surface can, for example, at least partially represent the bottom of the channel.

[0034] For optimal evaporation of the anesthetic agent, an even distribution of the anesthetic fluid is beneficial. A large surface area is also advantageous. Ideally, the anesthetic fluid should form a thin film covering the entire surface.

[0035] With an even distribution of the fluid, a defined, predictable evaporation rate can be achieved. For controlled anesthesia of the patient, it is also advantageous if the evaporation of the anesthetic, and accordingly the anesthesia of the patient, can be started and stopped quickly. Therefore, the evaporation device should always only contain as much anesthetic fluid as is needed for the anesthesia, without allowing anesthetic fluid to accumulate in the device. The evaporation rate depends, among other things, on the wetted area exposed to an air stream (breathing gas stream). To achieve good performance or a good response, it is necessary to quickly increase or decrease the wetted area depending on the required anesthetic concentration. To achieve this, the height of the fluid film should be minimized.In addition, the incoming liquid flow in the evaporation section should be quickly distributed over a large surface area. Response time describes how quickly changes in the supplied liquid flow cause a change in the concentration of the breathing gas.

[0036] Puddles of anesthetic fluid should be avoided. Puddles can reduce the evaporation rate and / or (negatively) influence the response of the evaporation device. Puddles would create fluid deposits with a smaller surface area, making the evaporation rate more difficult to calculate or completely unpredictable. Puddles can also adversely affect the controlled dosing of anesthesia and / or termination of anesthesia. The response of the evaporation device would be impaired because the anesthetic fluid could not evaporate in a completely controlled manner. Desired changes in anesthesia conditions would only occur with a time delay.

[0037] To ensure the anesthetic fluid is distributed evenly across the entire width of the evaporation section, a flat surface is advantageous. A flat surface prevents puddle formation. In some embodiments, it is conceivable for the surface to have a slight curvature in its transverse direction, which can promote the distribution of the anesthetic fluid across the width. However, the curvature should be so slight that evaporation is ensured before puddles form.

[0038] Starting from the section to which the anesthetic fluid is initially directed, the surface should be flat or slightly convex and / or concave in its transverse direction.

[0039] According to one embodiment, the area may be at least 20 cm 2 , preferably at least 40 cm 2 , in particular at least 50 cm 2According to one embodiment, the area may be a maximum of 400 cm 2 , preferably no more than 300 cm 2 , in particular no more than 200 cm 2 be.

[0040] According to one embodiment, the area can be between 50 cm 2 and 200 cm 2 , preferably between 100 cm 2 and 150 cm 2 , particularly preferably between 110 cm 2 and 130 cm 2 In an exemplary concrete embodiment, the area can be 120 cm 2 be.

[0041] The area should be large enough to allow the maximum specified amount of anesthetic to evaporate before the entire area is wetted and puddling occurs.

[0042] According to one embodiment, the area can extend over at least 50%, preferably at least 70%, particularly preferably at least 90% of the length of the channel. According to one embodiment, the evaporation section can extend over at least 50%, preferably at least 80%, particularly preferably 100% of the width of the channel.

[0043] In some embodiments, the surface may extend over the entire length of the channel. In some embodiments, the surface may extend only over a portion of the length of the channel. For example, the breathing gas inlet and / or the breathing gas outlet may be excluded and not be part of the evaporation section. In some embodiments, the surface may only be arranged downstream of the anesthetic inlet.

[0044] In some embodiments, the anesthetic inlet can also be positioned centrally. This is particularly suitable for embodiments with a convex or concave surface. The anesthetic inlet can then be designed to introduce the anesthetic centrally onto the surface, from where it can be distributed over the surface due to gravity.

[0045] In some embodiments, the surface may extend across the entire width of the channel. For example, the surface may fill the entire width of the bottom of the channel. In some embodiments, there may be a (small) distance from the edge, which may facilitate manufacturing.

[0046] According to one embodiment, the surface can have different height levels, so that the surface has a three-dimensional surface structure. The surface structure can be configured to increase the surface area and / or the wettability of the surface. This can promote the distribution of the anesthetic.

[0047] On the one hand, it can be advantageous to increase the surface area (relative to the area). By varying the height, a larger surface area can be achieved within a smaller area (relative to the surface area). To optimize the evaporation rate, a relatively small volume of breathing gas can come into contact with a relatively large anesthetic fluid surface, allowing optimal enrichment of the breathing gas with anesthetic agent.

[0048] According to one embodiment, the surface may be at least 2 times larger, preferably at least 4 times larger, particularly preferably at least 5 times larger than the area.

[0049] It can also be advantageous to increase the wettability of the surface. This allows the anesthetic fluid to form a thin film that wets the surface. The anesthetic fluid wets the surface of the evaporation section as soon as they come into contact. Wetting increases the contact area between the wetting fluid and the wetted solid surface. Wettability can vary depending on the type of anesthetic and thus its surface tension. Wettability can also vary depending on the material and / or surface properties of the evaporation section.

[0050] Increased surface wettability can be achieved, for example, by having different surface heights. If the adhesive forces are stronger than the cohesive forces within the liquid droplet, the liquid can spread across the surface.

[0051] The different height levels can also cause the liquid to be drawn against gravity due to capillary forces. As a result, a portion of the liquid can be (slightly) drawn upwards. This can also increase the liquid surface area. According to one embodiment, the surface can be roughened, grained, ribbed, corrugated, and / or grid-shaped. According to one embodiment, the surface can also be smooth. The inner surface of the channel can, for example, be treated after the workpiece has been manufactured in such a way that the desired surface structure is created—at least in the region of the evaporation section. This can be achieved either by (partial) material removal or by (partial) application of additional material.

[0052] Technologies for modifying surface properties are well known and include, for example, compressed air blasting with a solid blasting medium or laser etching. Material removal can be achieved, for example, by sandblasting. The effect of the sand can partially abrade the surface and thus shape it. Sandblasting can, for example, roughen or grain the surface. More targeted material removal can be achieved, for example, by laser etching. The effect of laser beams can shape the surface in a variety of ways.

[0053] According to one embodiment, the surface may comprise a material that promotes surface wettability and / or thermal conductivity. According to one embodiment, the surface may comprise a material that is castable and / or thermally conductive. By (partially) applying additional material to the surface, a simple, targeted, and cost-effective structuring of the surface can be achieved.

[0054] The material can be selected to be castable. For example, the material can be a metallic material or a plastic. Thus, the material can be cast or injected into a desired shape.

[0055] Alternatively or additionally, the material can be selected to be thermally conductive. This allows the material to conduct heat from the canal wall to the anesthetic.

[0056] Furthermore, it is advantageous to choose a material that is temperature-resistant, corrosion-resistant, chemically inert, and / or durable. Furthermore, the material can be selected so that it is easy to clean and can withstand, for example, disinfection and / or sterilization without losing its material properties.

[0057] According to one embodiment, the material can be thermally conductively bonded to the surface. The bond between surface and material can be achieved, for example, through a thermal joining process. For example, the bond between surface and material can be achieved through sintering. During sintering, workpieces can be bonded together by heating—optionally under increased pressure. The temperatures can remain below the melting temperature of the main components, so that the shape of the workpieces is retained.

[0058] Depending on the materials used, other types of connection are also conceivable, such as welding, surface welding, spot welding, soldering, gluing and the like.

[0059] According to one embodiment, the material may be a metal alloy. Alternatively or additionally, the material may comprise at least one of the following metallic materials: iron; steel, in particular stainless steel; copper; gold; silver; platinum; titanium; nickel; aluminum; zinc; tin; lead; magnesium.

[0060] In some embodiments, the material can also be a plastic. The plastic should be designed not to chemically interact with the anesthetics or their metabolites. Suitable examples include polytetrafluoroethylene or ethylene-propylene-diene.

[0061] In preferred embodiments, the material is chemically inert. Corrosion-resistant materials, such as precious metals (e.g., gold, silver, platinum) or semi-precious metals (copper), are particularly advantageous.

[0062] According to a particularly preferred embodiment, the material can be stainless steel. Stainless steels offer the advantage of particularly good corrosion resistance. Furthermore, stainless steels are conductive, temperature-resistant, and durable. Furthermore, stainless steels are particularly hygienic because they are very easy to clean. Stainless steel is also suitable for additive manufacturing processes such as welding or sintering. The stainless steel should preferably have a low iron content.

[0063] According to one embodiment, the material can be formed as a wire and / or as a wire mesh and / or as a wire cloth. According to one embodiment, the wire and / or the wire of the wire mesh and / or the wire of the wire cloth can have a diameter of at least 5 μm, preferably at least 10 μm, in particular at least 20 μm. According to one embodiment, the diameter of the wire can be at most 400 μm, preferably at most 300 μm, in particular at most 200 μm.

[0064] According to one embodiment, the wire diameter can be between 20 pm and 200 pm, preferably between 40 pm and 120 pm, particularly preferably between 60 pm and 80 pm. In an exemplary specific embodiment, the diameter of the wire can be 71 pm.

[0065] According to one embodiment, the wire can be arranged in a grid-like manner, wherein the wire grid and / or the wire mesh has a mesh size of at least 5 μm, preferably at least 10 μm, in particular at least 20 μm. According to one embodiment, the mesh size can be at most 400 μm, preferably at most 300 μm, in particular at most 200 μm.

[0066] According to one embodiment, the mesh size can be between 20 pm and 200 pm, preferably between 50 pm and 150 pm, particularly preferably between 90 pm and 110 pm. In an exemplary specific embodiment, the mesh size can be 106 pm.

[0067] The wire mesh can be designed as a mesh and / or woven fabric of intersecting wires (at equal intervals), forming a plurality of mesh cells. The mesh cells can be, for example, triangular, quadrangular, square, polygonal, or diamond-shaped.

[0068] The wire mesh, wire netting, or wire cloth offers the advantage of a particularly simple and effective surface design. The wire mesh provides an effective surface enlargement, which also allows the surface tension of the anesthetic fluid to be utilized for rapid fluid spread within the wire mesh. The wire mesh can also be designed to hold the anesthetic fluid in place due to surface tension, even if the device is or becomes slightly tilted. The aforementioned advantages are particularly evident with a mesh size of around 100 μm.

[0069] The key to using a wire mesh is ensuring a smooth connection between the mesh and the base body, i.e., to the desired areas of the inner wall of the channel. Care must be taken to ensure that no irregularities, such as bumps or cavities, occur, which could cause puddles of the anesthetic.

[0070] The shape of the individual grid elements within the wire mesh can be square or diamond-shaped. It can be advantageous if the individual grid elements are aligned at an angle to gravity.

[0071] According to one embodiment, the evaporation device can be designed to slope downwards in the longitudinal direction, starting from the respiratory gas inlet and / or the anesthetic inlet toward the outlet. Thus, in the operational state of the device, the evaporation section can be inclined to the horizontal, with the inclination being at an angle of at least 1°, preferably at least 2°, and particularly preferably at least 3°.

[0072] According to one embodiment, the evaporation section can be designed such that, when the evaporation device is in the operational state, it runs at least partially downwards from the respiratory gas inlet and / or the anesthetic inlet to the outlet, viewed in its longitudinal direction, wherein an angle of inclination of the downward-sloping evaporation section with respect to the horizontal is at least 1°, preferably at least 3°, particularly preferably at least 5°.

[0073] The incline can be advantageous because it allows gravity to contribute to the distribution of the anesthetic fluid. Due to the incline, the anesthetic fluid can be distributed longitudinally along the channel by gravity. The incline can also be advantageous because it can compensate for unevenness in the standing surface (e.g., the hospital floor).

[0074] A combination of surface structuring and a longitudinal inclination can be particularly advantageous. On the one hand, surface tension can pull the anesthetic fluid outward, ensuring that the (entire) width of the evaporation section is wetted. On the other hand, surface tension and gravity can pull the anesthetic fluid downstream, ensuring that the (entire) length of the evaporation section is wetted.

[0075] Due to the ability of the surface structure, particularly the wire mesh, to draw the anesthetic fluid against gravity, wetting of the evaporation section across its width is ensured even when the device is tilted slightly across its longitudinal axis. A small angle of inclination is sufficient and should not be chosen too large. The angle of inclination should be selected such that the anesthetic fluid does not flow longitudinally faster than evaporation progresses, in order to prevent puddles from forming at the base of the incline. The incline can be constant across the entire longitudinal direction or vary across only parts of the device's longitudinal direction. For example, the incline could be formed only in the front area—at the anesthetic inlet.

[0076] The higher the flow rate of the liquid anesthetic and, accordingly, the higher the evaporation rate, the larger the wetted surface. With an inclined surface, where the liquid is applied from above, distribution over a large area is ensured because gravity, assisted by capillary forces, spreads the liquid. Surface tension can pull the liquid sideways in the transverse direction. Surface tension and gravity can pull the liquid downwards in the longitudinal direction. The wire mesh can pull the liquid against gravity. Therefore, wetting of the entire transverse axis is ensured even when the device is tilted slightly about its longitudinal axis. It is very important that the wire mesh lies completely flat on the inner surface without bubbles.Each bubble affects the performance and / or response of the device because it must be filled with liquid before the wettable surface area increases due to the incoming liquid flow.

[0077] According to one embodiment, the evaporation section can be designed to be sloping and / or curved such that the partial section is elevated compared to the rest of the evaporation section. This offers the advantage that the anesthetic fluid is distributed from the partial section over the length and / or width of the rest of the evaporation section due to gravity.

[0078] According to one embodiment, the channel can be at least partially straight and / or curved in the longitudinal direction. According to a preferred embodiment, the channel can be curved in the longitudinal direction. Accordingly, the evaporation section can also be at least partially straight and / or curved.

[0079] According to one embodiment, the channel can have at least one bend in the longitudinal direction for deflecting the breathing gas. The bend can be designed such that the channel is bent into a U-shape at least once.

[0080] By bending the channel in the longitudinal direction, the evaporation device can be designed to be particularly space-saving. For example, the channel can be bent once, twice, or multiple times. The bend can be a total of 180°, for example, through a single 180° bend or through two consecutive 90° bends, creating a U-shaped bend. The breathing gas inlet and outlet can then be arranged adjacent to each other, and the flow of the breathing gas or breathing gas mixture can be deflected by 180°. In some embodiments, the deflection can also be greater than 180°.

[0081] According to one embodiment, the channel can comprise a first longitudinal section, a second longitudinal section, and a transition section connecting the first longitudinal section to the second longitudinal section, wherein the transition section is bent in a U-shape such that the longitudinal axes of the first longitudinal section and the second longitudinal section are parallel to one another. The U-shaped bend can also be greater or smaller than 180°, so that the longitudinal axes of the first longitudinal section and the second longitudinal section are not parallel to one another and run divergently or convergently. An overall U-shaped bend has proven advantageous because it allows the breathing gas inlet and the outlet to be arranged (relatively speaking) adjacent to one another.According to one embodiment, the channel can thus comprise a first longitudinal section, a second longitudinal section and a transition section connecting the first longitudinal section to the second longitudinal section, wherein the transition section is bent in a U-shape such that the outlet is adjacent to the breathing gas inlet.

[0082] The bend can also be greater or smaller than 90° or 180°, resulting in other shapes. For example, the channel can be curved in a serpentine manner along its length. The more frequent the bend, the more space-saving the device can be (in terms of its length) while maintaining a constant channel length.

[0083] A further advantage is that the breathing gas flow is deflected at least once in the longitudinal direction, which can reduce noise. Particularly quiet breathing gas flow can be achieved by deflecting the breathing gas flow multiple times. The breathing gas can thus be advantageously deflected at least once, preferably multiple times, in the duct.

[0084] According to one embodiment, the evaporation device may further comprise: an anesthetic conducting element configured to conduct the liquid anesthetic from the anesthetic inlet to the subsection.

[0085] The anesthetic conducting element can comprise a (vertical) surface along which the anesthetic fluid can slide (due to gravity). The anesthetic conducting element can offer the advantage of directing the anesthetic fluid from the anesthetic inlet directly to the evaporation section. The anesthetic conducting element can be configured to direct even the smallest amounts of anesthetic fluid to the evaporation section. The anesthetic conducting element can prevent anesthetic fluid from remaining in the form of a hanging droplet at the anesthetic inlet due to its cohesive forces and surface tension. Thus, the anesthetic conducting element can also enable very small fluid input.

[0086] According to one embodiment, the evaporation device may further comprise: a heating device configured to heat the evaporation section to a temperature for evaporating the anesthetic.

[0087] Since the anesthetic fluid requires heat energy during evaporation, which can be extracted from the liquid phase, the liquid phase (the anesthetic fluid) can cool down through evaporation. Since temperature can affect the evaporation rate, it is advantageous to control the temperature in the evaporation device. To counteract the cooling of the anesthetic fluid caused by evaporation, the heating device can heat the evaporation section.

[0088] "Heating device" can be understood as a device that can generate heat in or on the channel, in particular in or on the evaporation section. The heating device can, for example, be coupled to a control device of a ventilator and thus be controllable via the ventilator.

[0089] The heating device can, for example, be designed to heat the evaporation section with the aid of a suitable control system so that its actual temperature approaches the (optimal) temperature for evaporation of the anesthetic.

[0090] The heating device can also be configured to heat the evaporation section using a suitable controller, and thus without feedback of the actual temperature of the evaporation section, for example, at specific intervals, so that the average actual temperature of the evaporation section over several heating intervals approaches the temperature for evaporation of the anesthetic. It is conceivable that an associated ventilator is configured to alternately switch the heating device on and off. For example, the temperature for evaporation of the anesthetic can be between 10°C and 42°C.

[0091] The heating device can be designed, for example, as a heating element, heating rod, heating cartridge, heating wire, heating hose, heat radiator, resistance heater, or the like. The heating device can run along the entire evaporation section or be arranged in sections along the evaporation section. In some embodiments, it is possible to arrange several individually regulated or controlled heating devices along the channel, for example, 2, 3, 4, or more.

[0092] The heating device can transport heat into the channel wall and thus to the evaporation section. The heating device can, for example, be mounted on the outer wall of the channel or integrated into the channel material. The heating device can have a positive effect on controlled evaporation because it transfers heat energy to the channel wall, which in turn transfers the heat energy into the anesthetic fluid.

[0093] The surface of the evaporation section, which includes, for example, the (metallic) wire mesh, can have a positive effect on evaporation by transferring heat energy from the channel wall (through the mesh wires) to the anesthetic fluid. The wire mesh can increase the evaporation rate by providing thermal energy, as the fluid absorbs heat of vaporization during evaporation.

[0094] According to one embodiment, the channel can be designed such that a flow of the respiratory gas and / or the respiratory gas mixture in the channel is at least largely laminar; and / or wherein the evaporation device further comprises a flow guide element designed to generate targeted turbulence and / or mixing and / or circulation in a flow of the respiratory gas mixture in the channel.

[0095] According to one embodiment, the channel can be configured to conduct the respiratory gas and / or the respiratory gas mixture with a laminar flow. According to one embodiment, the evaporation device can further comprise a flow-guiding element configured to influence the flow of the respiratory gas mixture in the channel such that turbulence occurs in the flow and / or that the laminar flow is (multiple times) split and redirected so that the individual flows separate and remix with each other several times. The flow-guiding element can also be configured to conduct the respiratory gas from the inlet to the outlet in defined paths across the surface of the channel.

[0096] The flow guide element can be configured such that it is not directly connected to the base of the evaporation device. Thus, the evaporation device can be configured such that the anesthetic fluid can creep between the flow guide element and the base to wet the entire surface. "Laminar flow" can be understood as a flow that exhibits no, almost no, or negligible turbulence. The fluid can flow in layers that do not mix, or only minimally mix, with each other. The flow pattern of a laminar flow is uniform. Laminar flow can occur in a channel with a smooth inner wall that has no significant imperfections. Laminar flow can have a positive effect on pressure buildup.

[0097] "Turbulence" can be understood as the movement of the fluid being disordered, at least in sections. The flow pattern of a turbulent flow is irregular. Turbulence can include eddies, crossflows, and the like and lead to (increased) mixing of the fluid.

[0098] The flow guide element allows the initially orderly movement of the fluid, i.e., the breathing gas or the breathing gas mixture in the channel, to be transformed, at least in some areas, into a disordered, turbulent flow. The flow guide element can introduce small turbulences into the flow, which have a positive effect on the evaporation rate.

[0099] The turbulence can cause the air layers to mix. The turbulence can thus promote evaporation by disrupting and mixing the already saturated air layer located directly above the evaporation surface. This can ensure that the anesthetic concentration in the breathing gas is evenly distributed. This allows gas to flow along the entire length of the evaporation section that is not yet fully saturated and can therefore still absorb anesthetic.

[0100] Turbulence, such as small eddies, can promote evaporation by allowing a larger flow to flow over the anesthetic agent surface. Small turbulences in the otherwise laminar flow path can cause more unsaturated breathing gas to flow over the evaporation section and the anesthetic agent surface.

[0101] The flow guide element is particularly advantageous because it always delivers "fresh" breathing gas to the evaporation surface. With laminar flow, the lowest layer would become saturated with anesthetic vapor. Since this layer would no longer leave the surface, less anesthetic would evaporate downstream in the channel, as the layer closest to the surface would already be saturated. The flow guide element can break up this layer, allowing the air layers to mix, and unsaturated air to be directed back to the evaporation surface.

[0102] This can increase the evaporation rate and thus reduce the time required to evaporate a given amount of anesthetic. It can also reduce the size of the device required to evaporate a given amount of anesthetic.

[0103] The flow guide element can be configured to divide the airflow. A first portion of the flow is directed toward the evaporation section, where it can absorb anesthetic. A second portion of the flow remains in areas where no anesthetic is absorbed. The turbulence allows the saturated portion of the flow to return to the unsaturated portion, where the air streams mix.

[0104] Since both laminar flow and turbulent flow have advantages and disadvantages for the evaporation device, it can be particularly advantageous to combine them.

[0105] The evaporation device should, if possible, create little resistance to the flow of the breathing gas. Laminar flow, i.e., a channel section without a flow guide element, can ensure low resistance and thus a low pressure drop. However, the air layer directly above the anesthetic fluid surface can quickly become saturated with anesthetic. A saturated air layer cannot absorb any further anesthetic, so the overall evaporation rate can decrease.

[0106] A turbulent flow, i.e., a channel area with flow guide(s), can produce a good evaporation rate because the air layer directly above the anesthetic fluid surface is constantly exchanged through turbulence. This constantly forces new air over the anesthetic fluid surface, allowing for continuous absorption of additional anesthetic agent, which can increase the evaporation rate.

[0107] The flow guide element can be arranged in the channel in the region of the evaporation section. The flow guide element can be arranged throughout the entire evaporation section or only in certain regions. In some embodiments, it may be advantageous if the flow guide element is arranged only in certain regions of the evaporation section. For example, it may be advantageous if regions with a flow guide element and regions without a flow guide element alternate, so that the flow is laminar in some regions and turbulent in others.

[0108] The flow guide element can preferably be arranged such that the flow is (again) laminar when it is discharged from the channel via the outlet. This allows the flow to reorganize toward the end of the channel.

[0109] The flow guide element can be arranged at repeating intervals so that the effect can be repeated. This allows unsaturated fresh air to constantly flow through the evaporation section. A further aspect of the invention relates to a ventilator with a breathing gas line comprising an evaporation device as described above, wherein the evaporation device is connected to the breathing gas line of the ventilator via the breathing gas inlet and the outlet.

[0110] A "ventilator" can be understood as a device for anesthesia and / or ventilation. The ventilator can have a ventilation function and / or an anesthesia function. The ventilator can thus be used as a pure ventilator and / or as an anesthesia device.

[0111] A ventilator can therefore be understood as any device that supports a patient or other user in their natural breathing and / or performs ventilation and / or serves for respiratory therapy and / or inhalation anesthesia and / or otherwise influences the breathing of the patient or user. Patient and user are used synonymously herein and refer to any individual who is ventilated and / or anesthetized with a ventilator.

[0112] A further aspect of the invention relates to a method for mixing gases, in particular using the evaporation device described above, the method comprising the following steps:

[0113] Introducing a breathing gas into a channel;

[0114] Introducing an anesthetic in liquid form into the canal;

[0115] Evaporation of the anesthetic to mix the anesthetic with the breathing gas to provide the breathing gas mixture,

[0116] Discharging the breathing gas mixture from the channel, wherein the anesthetic is directed, upon introduction into the channel, to an evaporation section which is designed to distribute the anesthetic in the evaporation section.

[0117] A further aspect of the invention relates to a method for providing a breathing gas mixture, in particular using the evaporation device described above, the method comprising the following steps:

[0118] Introducing a breathing gas into a channel;

[0119] Introducing an anesthetic in liquid form into the canal;

[0120] Evaporation of the anesthetic to mix the anesthetic with the breathing gas to provide the breathing gas mixture,

[0121] Discharging the breathing gas mixture from the channel, wherein the anesthetic is directed, upon introduction into the channel, to an evaporation section which is designed to distribute the anesthetic evenly in the evaporation section in order to enable uniform evaporation of the anesthetic.

[0122] The anesthetic can preferably be distributed evenly over the evaporation section. The anesthetic can preferably be distributed over the evaporation section in such a way that the thinnest possible liquid film is formed on the evaporation section. This liquid film improves the response of the evaporation device.

[0123] Short description of the characters

[0124] Embodiments of the invention are described below with reference to the accompanying figures. The invention is not limited to the illustrated embodiments. Neither the description nor the figures are to be understood as limiting the scope of the invention. They show:

[0125] Figure 1 is a sectional side view of the evaporation device 1 according to a first embodiment of the invention;

[0126] Figure 2 shows a cross-section of the evaporation device 1, wherein Figures 2A-D show different embodiments of the device;

[0127] Figure 3 is a sectional view of the device 1 from Fig. 1 from above - looking towards the evaporation section 10;

[0128] Figure 4 is a sectional side view of the evaporation device 1 according to a second embodiment of the invention;

[0129] Figure 5 shows an evaporation device 1 according to a third embodiment of the invention in different views.

[0130] The figures are purely schematic and not to scale. Where the same reference symbols are used in different figures, these reference symbols designate identical or equivalent features. The coordinate systems shown in some figures serve to clarify the orientation of the views. The x, y and z axes describe the same direction in every figure unless otherwise stated. A direction designated by an x-axis in a figure therefore generally corresponds to the direction of the x-axis in the other figures. With reference to the evaporation device 1, the length L or longitudinal direction of the evaporation device 1 can be understood as the x-axis, the height H or vertical direction as the y-axis and the width B or transverse direction Q as the z-axis.

[0131] Figure 1 shows the evaporation device 1 according to a first embodiment of the invention. The evaporation device 1 is designed to provide a breathing gas mixture 8. The breathing gas mixture 8 is shown in the figure as a gray block arrow. The evaporation device 1 comprises a channel 2 with an inner surface 9. The inner surface 9 of the channel 2 comprises an evaporation section 10 for evaporating an anesthetic 6.

[0132] The channel 2 is designed as a hollow body and has a channel wall that encloses the lumen of the channel 2. More precisely, the inner surface 9 of the channel wall encloses the lumen. The channel 2 is designed to receive and / or conduct and / or discharge a breathing gas 4 or a breathing gas mixture 8 into its lumen. The breathing gas 4 is shown in the figure as a white block arrow.

[0133] The channel 2 has a length or longitudinal direction L, a height or vertical direction H, and a width B or transverse direction Q (see Fig. 2). The length L can generally be several times greater than the height H. The evaporation device 1 comprises a breathing gas inlet 3 for introducing a breathing gas 4 into the channel 2. The breathing gas inlet 3 can serve as a connection with which the evaporation device 1 can be hermetically connected to further channels, lines, or other components of a ventilator 100 or ventilation system (not shown in detail here). A breathing gas 4 can be introduced at the breathing gas inlet 3 in the longitudinal direction L of the channel 2. In some embodiments, it is also possible to achieve a deflection of the gas at the breathing gas inlet 3, for example by 90° (not shown).

[0134] Furthermore, the evaporation device 1 comprises an outlet 7 for discharging the respiratory gas mixture 8 from the channel 2. The outlet 7 can also serve as a connection with which the evaporation device 1 can be hermetically connected to further channels, lines, or other components of a ventilator 100 or ventilation system. A respiratory gas 4 or respiratory gas mixture 8 can be discharged via the outlet 7 in the longitudinal direction L of the channel 2. In some embodiments, it is also possible to deflect the gas at the outlet 7, for example, by 90° (not shown).

[0135] The evaporation device 1 can be integrated, for example, into the breathing gas line of a ventilator 100 via the breathing gas inlet 3 and the outlet 7. The evaporation device 1 can be integrated, for example, into an inspiratory branch of the ventilator 100, via which the patient is supplied with a breathing gas (mixture) (not shown).

[0136] A flow 17 of the respiratory gas can be specified via respiratory gas drives (blowers) and / or valves (not shown here) in the respiratory gas line of the ventilator 100. Thus, the flow 17 within the evaporation device 1 can also be specified, as shown in Figure 1 with the block arrows. In some embodiments, a respiratory gas drive can also be provided in the evaporation device 1 itself, which specifies the flow 17 in the channel 2 (not shown). The white block arrow symbolizes the main flow 17 of the respiratory gas 4. The gray block arrow symbolizes the main flow 17 of the respiratory gas mixture 8 enriched with anesthetic 6. The respiratory gas drive can be located upstream of the respiratory gas inlet 3 in the flow direction 17 and / or downstream of the outlet 7 in the flow direction 17. In a preferred embodiment, the breathing gas drive is located in the flow direction 17 after the outlet 7 and can convey the breathing gas mixture 8 enriched with anesthetic 6 to the patient.The channel 2 can be designed to guide the breathing gas 4 and / or the breathing gas mixture 8 with a flow that is laminar.

[0137] The evaporation device 1 comprises an anesthetic inlet 5 for introducing an anesthetic 6 into the channel 2 and / or the evaporation section 10 and / or the evaporation surface 12. The anesthetic inlet 5 is particularly designed to introduce the anesthetic 6 in liquid form into the channel 2 and / or the evaporation section 10 and / or the evaporation surface 12. The solid black arrows symbolize the liquid anesthetic 6. The main function of the anesthetic inlet is to direct the liquid anesthetic directly onto the surface or grid (and not simply to allow it to drip into the channel). Ideally, the inlet should be designed in such a way that it does not first form a drop that then drips off at some point, but rather that even with the smallest amounts or flow rates the liquid anesthetic is directed directly onto the surface / into the grid to be distributed or spread there.

[0138] The anesthetic 6 can, for example, be a volatile anesthetic. The volatile anesthetics can be selected from the group: isoflurane, sevoflurane, desflurane, halothane, enflurane, methoxyflurane. For the purpose of liquid introduction, the anesthetic inlet 5 can be designed to subject the anesthetic 6 to cooling and / or pressure. In preferred embodiments, the anesthetic 6 is exposed to a pressure at which the anesthetic 6 is in a liquid state. The pressure can, for example, be above 100 kPa, for example 180 kPa or greater. At an exemplary pressure of 180 kPa, the volatile anesthetics are in a liquid state at room temperature.

[0139] The anesthetic inlet 5 can be designed to keep the anesthetic 6 under pressure and to introduce it in liquid form under pressure into the channel 2 and / or the evaporation section 10 and / or the evaporation surface 12. The pressure in the anesthetic inlet 5 can be greater than the pressure prevailing in the channel 2. Thus, the anesthetic 6, for example the volatile anesthetics, can be introduced in liquid form via the anesthetic inlet 5 into the channel 2 and / or the evaporation section 10 and / or the evaporation surface 12, where it can evaporate and combine with the breathing gas 4. The dashed black arrows symbolize the evaporating anesthetic 6.

[0140] The anesthetic inlet 5 is designed to direct the liquid anesthetic 6 to a subsection 11 of the evaporation section 10. The evaporation section 10 comprises a surface 12 designed to evenly distribute the introduced anesthetic 6 from the subsection 11 into the evaporation section 10 to enable uniform evaporation.

[0141] While the inner surface 9 in the rest of the channel 2 does not need to have any special features, the surface 12 in the area of ​​the evaporation section 10 can be specially designed, namely in such a way that a uniform, rapid distribution of the anesthetic fluid 6 occurs over the largest possible area. This can be achieved by a three-dimensional surface structure. The three-dimensional surface structure can be realized by the nature of the surface material itself and / or by an (additional) element on and / or in the surface. The element can be designed, for example, as a wire, wire mesh, or wire cloth.

[0142] The partial section 11 is shown as a separate element in the figures for the sake of clarity. In some embodiments, however, the partial section 11 can also be an integral part of the evaporation section 10 and / or the surface 12 and its properties do not differ from the rest of the evaporation section 10 and / or the surface 12. In some embodiments, however, it is also conceivable for the partial section 11 to be designed as a sloping ramp or similar in order to quickly guide the anesthetic liquid 6 to the rest of the evaporation section 10 and / or the surface 12 (not shown). Figure 2 shows different embodiments of the evaporation device 1 in cross section. From Fig. 2 it can be seen that the height H and the width B of the channel 2 can be the same or can differ (slightly) from one another. In alternative embodiments, the height H and the width B of the channel 2 can also differ from one another.It has proven advantageous if the cross-section of channel 2 corresponds to the cross-section of the breathing gas line of a ventilator to be connected.

[0143] Fig. 2 further shows that channel 2 can have different cross-sectional shapes. Depending on the shape of the channel wall, channel 2 can have a purely rectangular cross-section (Fig. 2A). Channel 2 can also have a round or oval cross-section (not shown). A combination of round and rectangular wall elements is also possible (Fig. 2BD).

[0144] It may be advantageous for at least the bottom portion of channel 2, which includes evaporation section 10, to be straight or largely straight. Starting from section 11, onto which the anesthetic fluid 6 is initially directed, the surface may be flat (see Figs. 2A, 2C) or slightly curved (convex) in its transverse direction (see Figs. 2B, 2D).

[0145] Due to the curvature, section 11 is elevated compared to the remaining evaporation section 10 (see Fig. 2B, 2D). This allows the anesthetic fluid to be better distributed across the width of the remaining evaporation section due to gravity.

[0146] Figure 3 shows a sectional view of the evaporation device 1 from Fig. 1 from above. From Fig. 3 it can be seen that the evaporation section 10 can be designed as a surface with a length 10L and a width 10B. The surface F can, for example, be between 50 cm 2 and 200 cm 2 , preferably between 100 cm 2 and 150 cm 2 , particularly preferably between 110 cm 2 and 130 cm 2 large. In an exemplary concrete embodiment, the area F can be 120 cm 2 be big.

[0147] As can be seen from Fig. 3, the area F can extend over a large part of the length L of the channel 2, namely over at least 50%, preferably at least 70%, particularly preferably at least 90%.

[0148] Furthermore, it is shown that the area F can extend over a large part of the width B of the channel 2, namely over at least 50%, preferably at least 80%, particularly preferably 100%.

[0149] The surface 12 of the evaporation section 10 can be modified compared to the remaining inner surface 9 of the channel 2, which is shown in Fig. 3 by the hatching.

[0150] The surface 12 can be smooth, roughened, grained, ribbed, corrugated, and / or grid-shaped. This can be achieved, for example, by sandblasting or lasering the inner surface 9 in the area of ​​the evaporation section.

[0151] In some embodiments, the surface 12 of the evaporation section 10 can be configured such that the surface area is enlarged. This can be achieved by having the surface 12 at different heights and thus being designed three-dimensionally. The surface 12 can thus be at least 2 times larger, preferably at least 4 times larger, particularly preferably at least 5 times larger than the area F.

[0152] The surface 12 of the evaporation section 10 can alternatively or additionally be designed such that the wettability of the surface 12 is increased or improved.

[0153] In one embodiment, the surface 12 can also comprise an (additional) material 13. The material can preferably be castable. The material can preferably have good thermal conductivity and can also be thermally conductively bonded to the surface 12. Therefore, a metallic material such as iron or aluminum is particularly suitable.

[0154] A particularly preferred material 13 may be stainless steel, for example in the form of a wire 14 applied to the surface 12. In some embodiments, the wire 14 may have a diameter between 20 pm and 200 pm, preferably between 40 pm and 120 pm, particularly preferably between 60 pm and 80 pm.

[0155] As indicated in Fig. 3, the wire 14 can be arranged, for example, in a grid-like and / or woven pattern on the surface 12. The wire grid or wire mesh can then have a mesh size between 20 pm and 200 pm, preferably between 50 pm and 150 pm, particularly preferably between 90 pm and 110 pm. The grid cells can be triangular, quadrangular, square, polygonal, or diamond-shaped, for example. A particularly advantageous arrangement can be a 45° inclination to the longitudinal direction or to the main flow 17 of the respiratory gas or respiratory gas mixture.

[0156] In alternative embodiments not shown here, the evaporation device 1 can also be circular. The evaporation section 10 can also be circular, optionally with a concave (like a wok) or convex bottom surface F. The anesthetic inlet 5 could then, for example, also be arranged centrally. Flow guide elements 22 can be included and configured to guide the respiratory gas from the respiratory gas inlet 3 to the outlet 7 in a labyrinthine or spiral pattern over the entire surface. The flow guide elements 22 can preferably be arranged such that the anesthetic fluid 6 can creep between the flow guide elements 22 and the surface F to wet the entire surface (not shown).

[0157] Figure 4 shows a sectional side view of the evaporation device 1 according to a second embodiment of the invention. The figure shows that at least the evaporation section 10 can be designed to slope downwards in the longitudinal direction L, starting from the respiratory gas inlet 3 and / or the anesthetic inlet 5 toward the outlet 7. Thus, the evaporation section 10 can be inclined to the horizontal in the operational state of the device 1. The inclination can have an angle α of at least 1°, preferably at least 2°, particularly preferably at least 3°.

[0158] The inclination can be constant across the entire longitudinal direction L, as shown. In some embodiments, the inclination can also affect only partial areas of the evaporation section 10. For example, the inclination could be formed only in the front area—at the anesthetic inlet (not shown). Due to the inclination, the anesthetic fluid 6 can be distributed in the longitudinal direction L of the channel 2 by gravity g, shown as an arrow in the figure.

[0159] From Fig. 4 it can be seen that the evaporation section 10 is designed to slope in such a way that the partial section 11 is raised in comparison to the remaining evaporation section 10, so that the anesthetic liquid 6 is distributed from the partial section 11 over the length of the remaining evaporation section 10 due to the force of gravity.

[0160] Fig. 4 also shows that the device 1 may include an anesthetic conducting element 16. The anesthetic conducting element 16 may be configured to direct the liquid anesthetic 6 from the anesthetic inlet 5 to the subsection 11.

[0161] Furthermore, the device 1 can comprise a heating device 20. The heating device 20 can be designed to heat the evaporation section 10 to a temperature for evaporating the anesthetic 6. The heating device 20 can be designed, for example, as a heating element, heating rod, heating wire, or the like. The heating device 20 can be designed to transfer heat to the evaporation device 1, in particular to the evaporation section 10, via heat conduction and / or heat radiation and / or heat entrainment (convection). The heating device 20 can, as shown in Figure 4, be arranged without direct contact with the evaporation device 1 and transport heat to it. In alternative embodiments, the heating device can also be arranged in direct contact with the evaporation device 1 and transport heat to it.

[0162] In the exemplary embodiment outlined here, several individually regulated or controlled heating elements 20 are arranged along the channel 2, for example, three. More or fewer heating elements 20 are also possible. The heating device can preferably be detachably connected to the evaporation device. This offers the advantage of allowing separate cleaning of the evaporation device without subjecting the heating device to cleaning.

[0163] The channel 2 can, as shown in Figures 1, 3, and 4, run straight in its longitudinal direction L. Figure 5 shows an evaporation device 1 according to a third embodiment of the invention in various views. Figure 5A shows the evaporation device 1 in a sectional view from above, and Figures 5B and 5C show the same evaporation device 1 in different side views.

[0164] Shown here is a specific embodiment in which the channel 2 of the evaporation device 1 is curved in its longitudinal direction. The channel 2 has, for example, two bends 18 in the longitudinal direction. The bends 18 are designed such that the channel 2 is U-shaped overall.

[0165] In the specific embodiment shown, the channel 2 comprises a first longitudinal section 27, a second longitudinal section 28 and a transition section 29 connecting the first longitudinal section 27 to the second longitudinal section 28. The transition section 29 is bent in a U-shape such that the longitudinal axes of the first longitudinal section 27 and the second longitudinal section 28 are parallel to one another. For this purpose, the transition section has two bends 18, each of which introduces a 90° bend into the channel 2. In alternative embodiments, it is also conceivable for the bends 18 to be each greater or less than 90° or 180°, so that the longitudinal axes of the first longitudinal section 27 and the second longitudinal section 28 run divergently or convergently with respect to one another.

[0166] In other embodiments, the channel 2 can be bent only once or multiple times. The bend 18 can be made at least once by 180°, for example, by a single 180° bend or by two consecutive 90° bends as shown. This can then result in an overall U-shaped bend such that the breathing gas inlet 3 and the outlet 7 can be arranged (relatively speaking) adjacent to one another. The flow 17 of the breathing gas 4 or the breathing gas mixture 8 can thus be deflected by 180°.

[0167] The bend 18 can also be larger or smaller than 90° or 180°, resulting in other shapes. For example, the channel 2 can be curved in a serpentine manner in its longitudinal direction (not shown). Due to the bends 18, the device 1 can be designed to be particularly space-saving while maintaining a constant length of the channel 2.

[0168] Figures 5B and 5C show that, in this exemplary embodiment, the device 1 is also designed to slope downwards continuously in the longitudinal direction from the breathing gas inlet 3 to the outlet 7. Thus, the outlet 7 is located lower than the breathing gas inlet 3.

[0169] Figures 6-8 show the evaporation device 1 according to further embodiments of the invention in different views.

[0170] Figure 6 shows an embodiment of the evaporation device 1 in a perspective view. In the embodiment according to Fig. 6, the evaporation device 1 comprises flow guide elements 22. In this embodiment, the flow guide elements 22 are designed to influence the flow of the respiratory gas mixture 8 in the channel 2 in such a way that turbulence occurs in the flow (not shown).

[0171] The flow guide element 22 can be designed as a unit 23, which can comprise one or more flow guide elements 22. The unit 23 can be designed such that it can be inserted into the channel 2 and optionally also removed again. The removability of the unit 23 offers the advantage that cleaning the evaporation device 1 and its individual components is easier, better, and safer.

[0172] Such a flexibly deployable unit 23 can also offer the advantage that the flow guide elements 22 can be used as needed. If a high evaporation rate is to be achieved, the unit 23 can be used so that the device 1 can be used with flow guide elements 22. If a low pressure loss is to be achieved, the unit 23 can be removed from the device 1 so that it can be used without flow guide elements 22. Figure 6 shows, by way of example, that the device 1 can comprise three units 23. It is also conceivable that only one or two units 23 are used, or even more than three (not shown). This allows the evaporation device to be flexibly adjusted with regard to pressure drop and turbulence. Figure 7A shows a perspective view of a unit 23 with differently designed flow guide elements.The flow guide elements can be designed, for example, in the form of a plate 24 and / or in the form of a rod 25. In particularly advantageous embodiments, a plurality of plates 24 and rods 25 are included, which are arranged at regular or irregular intervals from one another.

[0173] Figure 7B shows a sectional view of a portion of the channel 2, which includes a unit 23 according to Figure 7A. Figure 7B shows that the plates 24 can extend into the channel 2. The plates 24 can be configured to deflect the flow. In particular, the plates 24 can be configured to deflect the flow toward the evaporation section 10. The plates can be straight or (partially) curved.

[0174] The rods 25 can be arranged at different locations in the channel 2. The rods 25 can be designed to alternatively or additionally generate (minor) turbulence in the flow. The rods can have a circular cross-section, as shown. Rods with an oval or angular cross-section are also conceivable (not shown). A combination of plates 24 and rods 26 has proven particularly effective. In other embodiments, it is also conceivable that only plates 24 (see Figure 8) or only rods 26 (not shown) are arranged in the channel 2.

[0175] Figure 7B further shows that the flow guide elements 24, 25 are not arranged directly on the evaporation section 10. There is a (small) distance to the surface 12 of the evaporation section 10 in order not to impede or prevent the distribution of the anesthetic liquid 6 on the evaporation section 10.

[0176] Figure 8A shows a perspective view of another embodiment of a unit 23 having flow guide elements in the form of plates 24. In this embodiment, the plates 24 are arranged in a lamella-like manner with a consistent structure. The plates 24 can be continuous or have a passage 26. The advantage of this embodiment lies in its particularly simple production.

[0177] Figure 8B shows a sectional view of a portion of channel 2, which includes a unit 23 according to Figure 8A. Figure 8B shows that the plates 24 can extend into channel 2 in a lamella-like manner. The plates 24 can be designed to deflect the flow 17. The plates 24 can be configured to deflect the flow 17 toward the evaporation section 10 and away from the evaporation section. The plates 24 can be arranged in channel 2 such that the breathing gas or breathing gas mixture is guided through channel 2 with a wave-like flow 17. This can provide sufficient mixing of the layers with relatively little local turbulence, so that a low pressure drop can be achieved at a high evaporation rate. Finally, it should be noted that terms such as "comprise," "comprise," "include," "with," etc.do not exclude other elements or steps, and indefinite articles such as "a" or "an" do not exclude pluralities.

[0178] Furthermore, it is noted that features or steps described with reference to one of the above embodiments may also be used in combination with features or steps described with reference to other of the above embodiments.

[0179] Reference numerals in the claims are not to be understood as limiting the scope of the subject matter defined by the claims. Although the present invention has been described in detail using exemplary embodiments, it is obvious to those skilled in the art that the invention is not limited to these exemplary embodiments. Rather, modifications are possible in such a way that individual features are omitted or different combinations of the described individual features can be implemented, provided the scope of the appended claims is not exceeded. The present disclosure includes all combinations of the presented individual features.

[0180] List of reference symbols

[0181] 1 evaporation device 2 channels

[0182] 3 Breathing gas inlet 4 Breathing gas

[0183] 5 Anesthetic inlet 6 Anesthetic / anesthetic fluid

[0184] 7 Outlet 8 Breathing gas mixture

[0185] 9 Inner surface 10 Evaporation section

[0186] 11 Section 12 Surface

[0187] 13 Material 14 Wire

[0188] 16 Anaesthetic guide element 17 Flow (breathing gas or breathing gas mixture)

[0189] 18 Bend 20 Heating device

[0190] 22 Flow guide element 23 Flow guide element / unit

[0191] 24 Flow guide element / plate 25 Flow guide element / rod

[0192] 26 Passage TI First Longitudinal Section

[0193] 28 Second longitudinal section 29 Transition section

[0194] 100 Ventilator 101 Breathing gas line F Area g Gravity (direction) H Height / vertical direction L Length / longitudinal direction Q Width / transverse direction a Angle to the horizontal

Claims

Patent claims 1. Evaporation device (1) for providing a breathing gas mixture (8), the evaporation device (1) comprising: a channel (2) with an inner surface (9); a breathing gas inlet (3) for introducing a breathing gas (4) into the channel (2); an anesthetic inlet (5) for introducing an anesthetic (6) in the liquid state into the channel (2); an outlet (7) for discharging the breathing gas mixture (8) from the channel (2), the discharged breathing gas mixture (8) comprising the breathing gas (4) and the anesthetic (6) in the evaporated state;wherein the inner surface (9) comprises an evaporation section (10) for evaporating the anesthetic (6), wherein the evaporation device (1) is designed such that the anesthetic (6) introduced into the channel (2) is directed to a partial section (11) of the evaporation section (10), wherein the evaporation section (10) comprises a surface (12) which is designed to distribute the anesthetic (6) directed to the partial section (11) from the partial section (11) into the remaining evaporation section (10); 2. Evaporation device (1) according to claim 1, wherein the surface (12) has different height levels, so that the surface (12) has a three-dimensional surface structure which is designed to increase the surface (12) and / or the wettability of the surface (12).

3. Evaporation device (1) according to one of the preceding claims, wherein the Surface (12) is roughened, grained, ribbed, corrugated and / or grid-shaped.

4. Evaporation device (1) according to one of the preceding claims, wherein the Surface (12) comprises a material (13) which promotes the wettability of the surface and / or the thermal conductivity.

5. Evaporation device (1) according to claim 4, wherein the material (13) is a metal alloy and / or comprises at least one of the following metallic materials: iron; steel, in particular stainless steel; copper; gold; silver; platinum; titanium; nickel; aluminum; zinc; tin; lead; magnesium.

6. Evaporation device (1) according to claim 4 or 5, wherein the material (13) is formed as a wire (14) and / or as a wire mesh and / or as a wire cloth.

7. Evaporation device (1) according to claim 6, wherein the wire (14) and / or the wire of the wire grid and / or the wire of the wire mesh has a diameter of at least 5 pm, preferably at least 10 pm, in particular at least 20 pm, and / or of at most 400 pm, preferably at most 300 pm, in particular at most 200 pm; and / or wherein the wire grid and / or the wire mesh has a mesh size of at least 5 pm, preferably at least 10 pm, in particular at least 20 pm, and / or of at most 400 pm, preferably at most 300 pm, in particular at most 200 pm.

8. Evaporation device (1) according to one of the preceding claims, further comprising: a heating device (20) which is designed to heat the evaporation section (10) to a temperature for evaporating the anesthetic (6).

9. Evaporation device (1) according to one of the preceding claims, wherein the channel (2) is at least partially straight and / or at least partially curved when viewed in its longitudinal direction (L).

10. Evaporation device (1) according to one of the preceding claims, wherein the channel (2) has at least one bend (18) for deflecting the respiratory gas (4) viewed in its longitudinal direction (L).

11. Evaporation device (1) according to one of the preceding claims, wherein the channel (2) comprises a first longitudinal section (27), a second longitudinal section (28) and a transition section (29) connecting the first longitudinal section (27) to the second longitudinal section (28), wherein the transition section (29) is bent in a U-shape such that the outlet (7) is adjacent to the breathing gas inlet (3).

12. Evaporation device (1) according to one of the preceding claims, wherein the evaporation section (10) is designed such that, when the evaporation device (1) is in the operational state, it runs at least partially downwards in its longitudinal direction (L) from the respiratory gas inlet (3) and / or from the anesthetic inlet (5) to the outlet (7), wherein an angle of inclination (α) of the downwards evaporation section (10) with respect to the horizontal is at least 1°, preferably at least 3°, particularly preferably at least 5°.

13. Evaporation device (1) according to one of the preceding claims, wherein the evaporation section (10) comprises a surface (F) with a length (10L) and a width (10B), wherein the length (10L) is greater than the width (10B), wherein the surface (F) is flat and / or at least partially curved in the direction of its length (10L) and / or in the direction of its width (10B).

14. Evaporation device (1) according to one of claims 12 or 13, wherein the evaporation section (10) is designed to be sloping and / or curved in such a way that the partial section (11) is raised in comparison to the remaining evaporation section (10), so that the anesthetic liquid (6) is distributed from the partial section (11) over the length (10L) and / or the width (10B) of the remaining evaporation section (10) due to the force of gravity.

15. Evaporation device (1) according to claim 13, wherein the area (F) is at least 20 cm 2 , preferably at least 40 cm 2 , in particular at least 50 cm 2 , and / or a maximum of 400 cm 2 , preferably no more than 300 cm 2 , in particular no more than 200 cm 2 , is large.

16. Evaporation device (1) according to one of the preceding claims, wherein the area (F) extends over at least 50%, preferably at least 70%, particularly preferably at least 90% of the length of the channel (2) and / or wherein the area (F) extends over at least 50%, preferably at least 80%, particularly preferably 100% of the width of the channel (2).

17. Evaporation device (1) according to one of the preceding claims, wherein the surface (12) is at least 2 times larger, preferably at least 4 times larger, particularly preferably at least 5 times larger than the area (F).

18. Evaporation device (1) according to one of the preceding claims, further comprising: an anesthetic conducting element (16) which is designed to conduct the anesthetic (6) in the liquid state from the anesthetic inlet (5) to the subsection (11).

19. Evaporation device (1) according to one of the preceding claims, wherein the channel (2) is designed such that a flow (17) of the respiratory gas (4) and / or the respiratory gas mixture (8) in the channel (2) is at least largely laminar; and / or wherein the evaporation device (1) further comprises a flow guide element (22) designed to generate targeted turbulence and / or mixing and / or circulation in a flow (17) of the respiratory gas mixture (8) in the channel (2).

20. Ventilator (100), comprising a breathing gas line (101) and a Evaporation device (1) according to one of the preceding claims, wherein the evaporation device (1) is connected to the breathing gas line (101) via the breathing gas inlet (3) and / or the outlet (7).

21. A method for mixing gases, in particular using an evaporation device (1) according to one of claims 1 to 18, wherein the method comprises the following steps: Introducing a breathing gas (4) into a channel (2); Introducing an anesthetic (6) in liquid state into the channel (2); Evaporation of the anaesthetic (6) to mix the anaesthetic (6) with the breathing gas (4) to provide the breathing gas mixture (8), Discharging the breathing gas mixture (8) from the channel (2), wherein the anesthetic (6) is directed, upon introduction into the channel (2), to an evaporation section (10) which is designed to distribute the anesthetic (6) in the evaporation section (10).

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