Gas exchange unit

Abstract

This includes a gas exchange unit with an eccentrically tilted inlet and a method for producing the gas exchange unit.

Description

[0001] The present invention relates to a gas exchange unit and a method for producing the gas exchange unit. Background Technology

[0002] In life-threatening lung disease patients, lung function can be maintained with an artificial lung (oxygenator or gas exchange unit) until the lungs recover and regain natural lung function. Extracorporeal circulation involves drawing blood from the patient, treating them in an oxygenator, and then returning the blood to the body.

[0003] The most well-known oxygenators were developed as part of a cardiopulmonary bypass machine for use during cardiac surgical procedures lasting several hours, and in most cases have not been optimized for long-term use. However, the duration of use as part of respiratory support is typically significantly longer, potentially lasting several weeks. During the long duration of use of known oxygenators, suboptimal flow paths due to high flow resistance and poor flushing areas can lead to, for example, hemolysis and thrombosis. The exchange capacity of such oxygenators also decreases, necessitating replacement during treatment, which can result in complications, as well as blood loss or severe hemodilution.

[0004] Conventional oxygenators are constructed, for example, of stacked hollow fiber pads arranged at right angles to each other. In the edge regions, the pads are embedded four times with castable material by rotation or centrifugation, creating a square cross-sectional surface over which blood flows. To ensure the blood is distributed as evenly as possible across the fiber surface, perforated distribution plates are used with conventional oxygenators, installed in the inlet and outlet regions. Such oxygenators are, for example, derived from WO 2017 / 211460 A1. Summary of the Invention

[0005] The objective of this invention is to improve flow guidance in oxygenators so as to meet the requirements of medium- to long-term respiratory support in a simple manner.

[0006] According to the invention, this task is achieved through the features of the independent claim. Further improvements to the invention are derived from the dependent claims.

[0007] According to the present invention, a gas exchange unit comprising a hollow fiber pad is provided, wherein the gas exchange unit includes an inlet positioned obliquely and eccentrically. To ensure that blood flow through the gas exchange unit is distributed as uniformly as possible across the circular fiber surface, and particularly to ensure sufficient flow in the edge regions, the blood rotates through the eccentrically positioned inlet. The hollow fiber pad has a circular cross-sectional surface. In a further improvement, the inlet of the gas exchange unit is eccentrically arranged relative to the fiber layers of the hollow fiber pad.

[0008] As described below, the gas exchange unit according to the invention omits a distribution plate, and the fluid (particularly blood) flows uniformly on the fibrous surface formed by a hollow fiber pad by other means or measures. Compared with known oxygenators, the gas exchange unit according to the invention has a longer application cycle or service life. The possibility of blood damage is also very low through the gas exchange unit.

[0009] The hollow fiber pads of the gas exchange unit are formed of hollow fibers. A gas exchange unit may include one or more hollow fiber pads. The fiber orientation of one fiber pad may be arranged at an angle to the fiber orientation of another fiber pad. Crossing the fiber pads can improve gas exchange characteristics and blood flow.

[0010] The gas exchange unit is also described as an oxygenator. An oxygenator is a device that enriches the blood with oxygen and removes carbon dioxide from the blood. Therefore, the lungs can be replaced or supported by an oxygenator for short periods and over longer periods.

[0011] In a further improvement, the gas exchange unit is envisioned with an inlet located on the facing side of the unit's housing. This inlet placement on the facing side allows for uniform flow through the hollow fiber pad. The gas exchange unit's housing includes an inlet housing.

[0012] Further improvements to the gas exchange unit envision an inlet connected to an inlet housing, the surface of which is structured. A suitable structure on the internal blood delivery surface of the inlet housing further ensures the most uniform distribution of flow. The inlet is positioned obliquely when the angle between the central axis of the inlet and the horizontal plane including the inlet housing is greater than 0° and / or less than 90°.

[0013] In further improvements to the gas exchange unit, these structures are envisioned as blade-shaped, bridge-shaped, or arranged as transverse members on the surface of the inlet shell. Blade-shaped, bridge-shaped, or transverse member arrangements allow for uniform distribution of flow across the fiber surfaces or uniform supply to the fiber surfaces within the gas exchange unit. The flow is consistent in both the internal and external regions of the hollow fiber pad.

[0014] Further improvements to the gas exchange unit are envisioned, with the inlet having a cross-sectional surface that widens continuously along the flow direction, allowing the flow velocity to decrease slowly rather than abruptly. A ratio of dD / 2dL < 1 between the inlet diameter (dD) and the extension length (dL) is advantageous. (In other words, the ratio between the inlet radius and the extension length is less than 1). This ratio varies along the extension length. This ratio can also vary gradually within the inlet region.

[0015] With further improvements, the diameter of the inlet is widened by less than 45° over the extension length.

[0016] Based on further improvements to the gas exchange unit, it is envisioned that the inlet cross-sectional surface widens asymmetrically. This widening can be symmetrical to guide the flow in a targeted manner and thus distribute it uniformly.

[0017] In a further improvement to the gas exchange unit, it is envisioned that the inlet has a cross-sectional surface that is variable along the length of the inlet.

[0018] In a further improvement to the gas exchange unit, it is envisioned that the gas exchange unit has an outlet whose cross-sectional surface decreases along the flow direction. The fluid (especially blood) is accelerated by continuously reducing the cross-sectional surface. A ratio of less than 1 between the diameter widening (dD) and the extension length (dL) is advantageous: dD / dL < 1 or dD / 2dL.

[0019] According to another further improvement of the gas exchange unit, it is envisioned that the gas exchange unit has an outlet including a deflector. To achieve the most compact gas exchange unit, the flow of fluid (especially blood) can be deflected at a certain angle on the outlet side. The deflection angle is approximately 90° or between 70° and 90°. This deflection may cause secondary turbulence or flow separation in the fluid (especially blood). However, the continuous reduction in the cross-sectional surface area of ​​the outlet accelerates the fluid, thereby counteracting or almost preventing the formation of secondary turbulence or flow separation.

[0020] According to an independent concept of the invention, the gas exchange unit or oxygenator includes a ventilation device, which is particularly arranged substantially centrally. If air is drawn in, it is collected in the middle of a swirling flow, particularly within the cavity of the gas exchange unit, due to the inlet geometry formed by the inlet and the inlet housing. The air is then drawn out by the ventilation device. The ventilation device also serves as an outlet for bubbles that may accumulate at these points during operation. The ventilation device can also be used for blood sampling during patient treatment.

[0021] To prevent the formation of blood clots (thrombi), all areas of the ventilation system must be able to be flushed, or blood must be prevented from stagnating.

[0022] The ventilation device can be designed such that it can optionally operate in a first operating condition, in which the ventilation device is flushed, or it can be switched to a second operating condition, in which the cavity of the gas exchange unit is ventilated. Thus, two technical functions can be advantageously achieved by the ventilation device: cavity ventilation and ventilation device flushing and therefore cleaning. The ventilation device is preferably flushed after the ventilation process to prevent any blood residue that may have flowed out during ventilation from remaining in the ventilation device. Alternatively, the ventilation device can optionally be switched to the first operating condition or to the second operating condition, in which ventilation of the cavity of the gas exchange unit is not performed, and in which ventilation of the cavity of the gas exchange unit is performed. With this design, only one technical function, namely cavity ventilation, can be achieved using the ventilation device.

[0023] The gas exchange unit may have a negative pressure source that is fluidly connected to the ventilation device. By applying negative pressure to the ventilation device using the negative pressure source, it is easy to ensure that air located in the cavity can be exhausted from the cavity.

[0024] In a further improvement to the gas exchange unit, it is envisioned that the ventilation device includes a flexible membrane. The central region of the inlet is made of a flexible material, allowing its inner side to be folded outwards for ventilation purposes, thereby creating a larger volume on the blood side to collect air bubbles.

[0025] The gas exchange unit may have a regulating element for switching the ventilation system to a first operating condition or a second operating condition. Depending on the specific circumstances, the regulating element may be designed differently, as explained in more detail below.

[0026] The ventilation device may have a closing piston that is moved to a first position to achieve a first operating condition or to a second position to achieve a second operating condition. The closing piston may be linearly movable and / or rotatably mounted such that it can be moved from the first position to the second position and vice versa. Specifically, the closing piston may be mounted to rotate about its longitudinal axis. Alternatively or additionally, the closing piston may be designed such that a piston segment moves relative to another piston segment to move the closing piston from the first position to the second position.

[0027] The closed piston may have a fluid line that is not fluidly connected to the cavity in a first position of the closed piston, but is fluidly connected to the cavity in a second position. Additionally, the fluid line may be fluidly connected to a supply line for supplying flushing agent in the first position of the closed piston, but not fluidly connected to a supply line in the second position. In the second position, air in the cavity can be expelled from the cavity via the fluid line. With this design, the closed piston can be rotatably mounted, and the adjusting element can be designed such that the closed piston rotates when the adjusting element is actuated. The adjusting element is preferably connected to the closed piston in a torsional-resistant manner.

[0028] With further improvements, the sealing ring of the ventilation device can be fitted onto the closed piston. Additionally, the ventilation device can have a reset member operably connected to the closed piston in such a way that the reset member pushes the closed piston from a second position to a first position. With this design, the closed piston can be mounted in a linearly movable manner. The reset member can be a spring, particularly a pressure spring. A force, particularly a linear force, is applied to the closed piston via an adjusting element to move the closed piston from the first position to the second position. The adjusting element can be, for example, a syringe.

[0029] In a further improvement, the sealing piston can have a weakness designed such that, in the second position of the sealing element, the adjusting element protrudes through the sealing piston. In the first position of the sealing piston, despite the weakness, the sealing piston can still prevent air or blood from leaving the cavity. The adjusting element can be a suction tube with at least one opening in its section protruding through the sealing piston. Air in the cavity can be expelled from the cavity via this opening and the adjusting element. The weakness of the sealing piston can be achieved through a cut in the sealing piston.

[0030] To further improve the gas exchange unit, in one further improvement, a hollow fiber pad is envisioned embedded within the gas exchange unit, featuring a sloping transition from the embedded hollow fiber pad to adjacent components. The location of the transition from the free fiber to the embedded fiber (filling height) may have imprecise tolerances. Even at different filling heights, the sloping transitions of adjacent blood delivery components produce a smooth, shock-free, and therefore blood-friendly transition. The sloping transition also greatly simplifies the manufacturing process of the gas exchange unit, as tolerances result in lower quality loss over a wider range during manufacturing. In a further improvement to the gas exchange unit, a stabilizer is envisioned for the inlet housing. To increase the stability of the inlet housing during filling, a stabilizer is provided. These stabilizers can be designed as bridges or lateral members. Therefore, during filling, which can reach high temperatures and / or tensions, the inlet geometry can be maintained and will not substantially change due to temperature variations.

[0031] Known oxygenators typically use hollow fibers that are first closed at their ends and then embedded in a polyurethane adhesive. This filling step is performed by a rotational method to prevent the fibers from adhering due to capillary action in areas where blood will subsequently be delivered, and to create a defined transition between the filling material and the free fibers. The fibers are then cut open from the outside, transverse to the fiber direction, with the cured filling material to allow subsequent flow of gas through them. The filling step is usually performed at both ends of the fibers, and therefore, an oxygenator with parallelly arranged fibers will result in two filling processes, or a stacked fiber pad will result in four filling steps.

[0032] According to the present invention, a method for manufacturing a gas exchange unit is provided. The method includes: inserting a casting for embedding fiber ends, wherein this insertion is performed once to form a cylindrical cavity in the central region of the gas exchange unit.

[0033] The gas exchange unit according to the invention is made of stacked hollow fiber pads. By means of a method for producing the gas exchange unit, a casting for embedding the fiber ends is introduced in a centrifuge in a single step, creating a cylindrical cavity in the central region of the gas exchange unit, in which the hollow fibers come into contact with a liquid, particularly blood. The cylindrical cavity results in uniform flow through the fiber pads. A requirement for this is consistent flow to the face-to-face surfaces of the cylindrical cavity. The chosen construction shape achieves a gas exchange unit with lower production costs due to fewer manufacturing steps (because the fibers are embedded in a single working step). In the case of gas exchange units currently available on the market, fiber embedding is carried out in a centrifuge in two or even four time-consuming steps.

[0034] The method also allows all blood-contacting components to be added in a single work step. No further gluing is required.

[0035] In contrast, in known oxygenators, uniform flow occurs via a distribution plate or diffuser through a fiber pad, which selectively increases flow resistance to varying degrees, thereby distributing blood flow. A disadvantage here is that the additional shear stress and irritation can damage the blood. Thrombosis can also occur in the rear region of the distribution plate, where flow is interrupted because a wake space may be created there. The measures of the present invention eliminate the need for such a plate. Attached Figure Description

[0036] Further details of the invention can be found in the exemplary embodiments described below with reference to the accompanying drawings.

[0037] Figure 1 Examples of embodiments of gas exchange units,

[0038] Figure 2 Further examples of embodiments of the gas exchange unit,

[0039] Figure 3 : Figure 2 Inlet shell

[0040] Figure 4 Examples of embodiments of the surface of the inlet housing.

[0041] Figure 5 Cross-sectional view of the inlet shell.

[0042] Figure 6A and Figure 6B According to an embodiment example of the ventilation device of the first design,

[0043] Figure 7 According to the perspective drawing of the ventilation device of the second design,

[0044] Figure 8 : Figure 7 The enlarged illustration of the section shown indicates that the ventilation system is in its first operating state.

[0045] Figure 9 : Figure 8 Cross-sectional view of the section shown.

[0046] Figure 10 : Figure 7 The enlarged illustration of the section shown indicates that the ventilation system is in its second operating state.

[0047] Figure 11 : Figure 10Cross-sectional view of the section shown.

[0048] Figure 12 According to the perspective drawing of the ventilation device in the third design,

[0049] Figure 13 : Figure 12 The enlarged illustration of the section shown indicates that the ventilation system is in its first operating state.

[0050] Figure 14 : Figure 13 Cross-sectional view of the section shown.

[0051] Figure 15 : Figure 12 The enlarged illustration of the section shown indicates that the ventilation system is in its second operating state.

[0052] Figure 16 : Figure 15 Cross-sectional view of the section shown.

[0053] Figure 17 According to the cross-sectional diagram of the ventilation device in the fourth design, the ventilation device is in the first operating state.

[0054] Figure 18 According to the cross-sectional diagram of the ventilation device in the fourth design, the ventilation device is in the second operating state.

[0055] Figure 19 According to the cross-sectional diagram of the ventilation device in the fifth design, the ventilation device is in the first operating state.

[0056] Figure 20 According to the cross-sectional diagram of the ventilation device in the fifth design, the ventilation device is in the second operating state.

[0057] Figure 21 According to the cross-sectional diagram of the ventilation device in the sixth design, the ventilation device is in the first operating state.

[0058] Figure 22 According to the cross-sectional diagram of the ventilation device in the sixth design, the ventilation device is in the second operating state.

[0059] Figure 23 Examples of embodiments of the outlet shell,

[0060] Figure 24 : Cross-sectional view of the outlet. Detailed Implementation

[0061] Examples of embodiments of the present invention will be described below with reference to the accompanying drawings:

[0062] Figure 1An embodiment example of a gas exchange unit 1 is shown, which includes a hollow fiber pad (not shown). The gas exchange unit 1 includes an inlet 7, which is eccentrically arranged on an inlet housing 5. The inlet 7 is positioned obliquely relative to the inlet housing 5. The inlet 7 is arranged on the facing side of the housing of the gas exchange unit 1, which includes the inlet housing 5 and allows uniform flow through the hollow fiber pad. The inlet housing 5 forms the facing side of the housing of the gas exchange unit 1. The edge region of the inlet housing 5 is covered by the housing portion 3 of the gas exchange unit 1 (e.g., comparative). Figure 1 ).

[0063] Figure 2 A further embodiment example of the gas exchange unit 1 is shown. The surface of the inlet housing 5 has a structure 6 that further distributes the flowing blood as evenly as possible across the internal blood delivery surface of the inlet housing 5. The inlet housing 5 may optionally have Figure 3 The stabilizer 8 is shown. The stabilizer 8 can be designed as a bridge or a lateral member. Through potting (which can reach high temperatures and / or tension during potting), the inlet geometry of the inlet housing 5 is thus maintained and does not substantially change during temperature and / or tension variations.

[0064] Figure 3 It shows Figure 2 The inlet housing 5. The eccentric, oblique arrangement of the inlet 7 is clearly identifiable. The structure 6, which uniformly distributes the flow in the gas exchange unit 1, is designed as a blade-shaped structure 6a and a bridge-shaped structure 6b. The structure 6 can also be arranged as a transverse member on the surface of the inlet housing 5.

[0065] These structures 6 mean that the flow of gas through the fiber surface of the hollow fiber pad in the gas exchange unit 1, or the supply to it, occurs consistently in both the internal central region and the external region of the hollow fiber pad, the external region including the edge region of the hollow fiber pad.

[0066] Figure 4 An example embodiment of the structured surface of the inlet housing 5 is shown in top view. The different dimensions of the blade-shaped structure 6a are identifiable. It ensures a consistent and uniform flow through the gas exchange unit 1.

[0067] Figure 5 A cross-sectional view of the inlet housing 5 is shown. The oblique positioning of the inlet 7 and the eccentric device are also visible in this figure. The inlet housing 5 includes a structure 6. A hollow fiber pad 32 is embedded in the gas exchange unit 1 and contacts the inlet housing 5. The inlet housing 5 has an oblique transition portion 9 in the contact area between the hollow fiber pad 32 and the inlet housing 5. There may be imprecise tolerances in the position (filling height) of the corresponding transition portion 9 from the free fibers to the embedded 10 fibers.

[0068] Even at different filling heights, the tilting transition section 9 produces a consistent, smooth, and therefore blood-friendly transition.

[0069] Figure 6A and Figure 6B An example embodiment of the ventilation device 15 is shown. If air is accidentally drawn in, it will accumulate at the center of the rotating flow due to the inlet geometry formed by the inlet 7 and the inlet housing 5. The air is then drawn out by the ventilation device 15. The ventilation device 15 also serves as an outlet for the air bubbles. The ventilation device 15 includes a ventilation duct 19.

[0070] The ventilation device 15 includes a flexible membrane 17. Figure 6A The membrane 17 is shown without ventilation. During ventilation, as... Figure 6B As shown, the inner side of membrane 17 is everted, thereby creating an increased volume on the blood side to collect air bubbles.

[0071] Figure 7 A perspective view of a ventilation device 15 according to a second design is shown. The ventilation device 15 is arranged next to the inlet 7. The ventilation device 15 is also fluidly connected to a negative pressure source 16 via a conduit 22. The negative pressure source 16 is designed as a syringe.

[0072] Figure 8 yes Figure 7 An enlarged view of the section shown. The gas exchange unit 1 has an adjustment element 21 in the form of a rotary lever, through which the ventilation device 15 can be selectively switched to a first operating condition or a second operating condition. Figure 8 In the design shown, the ventilation device is in the first operating state.

[0073] Figure 9 It shows Figure 8 The diagram shows a cross-sectional view of the section. From Figure 9 Clearly, the ventilation device 15 has a closed piston 18, which is connected to the regulating element 21 in a torsion-resistant manner. The fluid line 19 is located within the closed piston 18. Figure 8 In the first position of the enclosed element 18 shown, the fluid line 19 is oriented in such a way that the fluid line 19 is not in fluid contact with the line 22. This design prevents the flushing of the ventilation system.

[0074] Figure 10 It also shows Figure 7 An enlarged view of the section shown. (Through...) Figure 10 The design shown indicates that the adjusting element 21 has been rotated, putting the ventilation device 15 into a second operating state.

[0075] Figure 11 It shows Figure 10The diagram shows a cross-sectional view of the section. In the second operating condition of the ventilation device 15, the sealing piston 18 is positioned in a second position, in which the fluid line 19 is in fluid connection with the cavity 23 of the gas exchange unit 1. Additionally, the cavity 23 is in fluid connection with the line 22, and therefore with... Figure 7 The negative pressure source 16 shown is in fluid connection. In the second position of the closed piston 18, the air collected in the cavity 23 can be discharged via the fluid line 19 and the line 20.

[0076] Figure 12 A perspective view of a ventilation device according to a third design is shown. The ventilation device 15 is fluidly connected to a negative pressure source 16 via a pipe 22. Figure 12 Exhibition design and Figure 7 The difference in the displayed design lies in the design of the adjustment element 21. From Figure 13 Clearly, the adjustment element 21 is designed as a knob.

[0077] Figure 14 It shows Figure 13 A cross-sectional view of the ventilation device 15 and the regulating element 21 shown. Figure 14 Clearly, in the first position of the adjusting element 18, there is no fluid connection between the line 22 and the cavity 23. Therefore, in the first position of the closed piston 18, the air in the cavity 23 cannot be expelled. The closed piston 18 is connected to the adjusting element 21 in an anti-torsional manner.

[0078] Figure 15 It shows Figure 12 An enlarged view of the ventilation device 15 and adjusting element 21 is shown, with the ventilation device 15 in a second operating state. The adjusting element 21 is rotated to switch the ventilation device 15 from a first operating state to the second operating state.

[0079] Figure 16 It shows Figure 15 The diagram shows a cross-sectional view of the ventilation device 15 and the regulating element 21. In the second position of the closed piston 18, there is a fluid connection between the cavity 23 and the pipeline 22. The closed piston 18 moves linearly to transfer the closed piston 18 from the first position to... Figure 16 The second position is shown. The air collected in cavity 23 can be discharged to negative pressure source 16 through the gap between the closed piston 18 and the ventilation device housing 31 and via pipeline 22.

[0080] Figure 17A cross-sectional view of a ventilation device according to the fourth design is shown. The closing piston 18 of the ventilation device 15 differs from the aforementioned closing piston in that it has a weakness 25. Weakness 25 is equivalent to a cutout in the closing piston 18. Weakness 25 is located here in the region of the closing piston 18 extending into the cavity 23. A further difference is that the closing piston 18 includes a recess 26. Figure 17 In the middle, the closed piston 18 is in the first position, so that the air collected in the cavity 23 cannot be discharged.

[0081] Figure 18 A cross-sectional view of a ventilation device 15 according to a fourth design is shown, wherein the ventilation device 15 is in a second operating state. From Figure 18 Clearly, the adjusting element 21 passes through the closed piston 18. Specifically, the adjusting element 21 passes through the closed piston in the region of its weak point 25. As a result of the adjusting element 21 passing through the closed piston 18, piston segment 33 and another piston segment 34 move away from each other. The adjusting element 21 is partially arranged in the recess 26. The adjusting element 21 has an opening 27 in its segment located in the cavity 23, through which air is discharged from the cavity 23.

[0082] Figure 19 A cross-sectional view of a ventilation device 15 according to the fifth design is shown. The ventilation device 15 has a sealing ring 29 fitted onto a closed piston 18. Additionally, the ventilation device 15 has a reset device 30, which is designed to cause the closed piston 18 to... Figure 20 Press the second position shown. Figure 19 The first position is shown. The reset element 30 supports itself on the closed piston 18 at one end and on the ventilation housing 31 at the other end.

[0083] Figure 20 A cross-sectional view of a ventilation device 15 according to the fifth design is shown, wherein the ventilation device 15 is in a second operating state. From Figure 20 Clearly, the closing piston 18 moves linearly via an adjusting element 21 (not shown). The closing piston 18 is specifically pressed into the cavity 23 so far that a gap exists between the closing piston 18 and the ventilation housing, through which air collected in the cavity 23 is discharged. The air discharged from the cavity flows through line 20 to the negative pressure source 16. When the closing piston 18 moves to the second position, the reset element 30 is tensioned.

[0084] Figure 21 A cross-sectional view of a ventilation device 15 according to a sixth design is shown, wherein the ventilation device 15 is in a first operating state, in which the ventilation device 15 is being flushed. Figure 21The first position of the closed piston 18 is shown, with the fluid line 19 of the closed piston 18 in fluid connection to the supply line 20. Flushing agent is added via the supply line 20, flowing through the fluid line 19 as indicated by the arrow, and exiting via the closed piston 18. In the first operating condition, there is no fluid connection between the fluid line 19 and the cavity 23.

[0085] Figure 22 A cross-sectional view of a ventilation device 15 according to the sixth design is shown, wherein the ventilation device 15 is in a second operating state, in which a ventilation process is performed. In the second position of the closed piston 18, there is a fluid connection between the fluid line 19 and the cavity 23. As indicated by the arrow, air present in the cavity 23 can be discharged via the fluid line 19.

[0086] Figure 23 An example embodiment of the outlet housing 11 is shown. The outlet housing 11 has an outlet 12. Figure 22 As shown in the cross-sectional view of the outlet, the cross-sectional surface of outlet 12 decreases along the flow direction. Inlet housing 5, outlet housing 11, and housing portion 3 form the housing of gas exchange unit 1.

[0087] The outlet 12 has a deflection section 13. The deflection angle is 90°, but it can also be between 70° and 90°. The continuous reduction in the cross-sectional surface of the outlet 12 accelerates the fluid (blood), thereby effectively counteracting the formation of secondary turbulence or flow separation.

[0088] The outlet housing 11 may optionally have a stabilizer 8, which can be designed as a bridge or a lateral member. During the potting process, which can reach high temperatures, the geometry of the outlet housing 11 is thus maintained and will not substantially change if the temperature varies.

[0089] Figure 24 A cross-sectional view of outlet 12 is shown. The cross-sectional surface 10 of outlet 12 continuously narrows in the direction of fluid (blood) flow in a region (deflection section 13) that varies along the main flow direction. The flow direction is indicated by arrows. The narrowing can be asymmetrical. The cross-sectional surface 10 can be variable along the length of outlet 12. The fluid (blood) is accelerated by the continuous reduction of the cross-sectional surface on the outlet side of the gas exchange unit 1.

[0090] It should be noted that the methods, apparatuses, and systems described in this document can be used alone or in combination with other methods, apparatuses, and systems described in this document. All aspects of the methods, apparatuses, and systems described in this document can also be combined with each other in many ways. In particular, the features of the claims can be combined with each other in many ways.

[0091] The invention has been described in detail with reference to the accompanying drawings and the foregoing description. However, the invention can be embodied in many different forms and should not be construed as limited to the embodiments shown herein. Rather, these embodiments are provided to make this disclosure thorough and complete, and are not intended to exhaustively describe the full scope of the invention for those skilled in the art. The terminology used in the detailed description of the embodiments shown in the drawings is not intended to limit the invention. The same reference numerals in the drawings refer to the same elements.

Claims

1. A gas exchange unit for enriching blood with oxygen and removing carbon dioxide from the blood, comprising a hollow fiber pad, a housing having an inlet housing, an inlet for the blood, the inlet being eccentrically arranged on the inlet housing and inclined relative to the inlet housing in such a way that the blood is arranged to rotate, and wherein... A suitable structure is arranged on the internal blood delivery surface of the inlet housing in such a way that the flow of blood is distributed as evenly as possible and configured to cause a consistent and uniform flow through the gas exchange unit to better enrich the blood with oxygen and remove carbon dioxide from the blood. The suitable structure is blade-shaped, bridge-shaped, or arranged as a transverse member on the surface of the inlet housing, and the blade-shaped structure has different dimensions.

2. The gas exchange unit according to claim 1, wherein, The inlet is located on the housing of the gas exchange unit.

3. The gas exchange unit according to claim 1 or 2, wherein, The inlet is connected to the inlet housing, and the surface of the inlet housing has a structure.

4. The gas exchange unit according to claim 1 or 2, wherein, The inlet has a cross-sectional surface that widens continuously along the flow direction.

5. The gas exchange unit according to claim 1 or 2, wherein, The diameter of the inlet widens by less than 45° along its extension length.

6. The gas exchange unit according to claim 1 or 2, wherein, The inlet has a cross-sectional surface that widens asymmetrically.

7. The gas exchange unit according to claim 1 or 2, wherein, The inlet has a cross-sectional surface with a variable length along the inlet.

8. The gas exchange unit according to claim 1, wherein, The gas exchange unit has an outlet, the cross-sectional surface of which decreases continuously along the flow direction.

9. The gas exchange unit according to claim 1, 2 or 8, wherein, The gas exchange unit has an outlet including a deflector.

10. The gas exchange unit according to claim 1, comprising a ventilation device.

11. The gas exchange unit according to claim 10, wherein, The ventilation device is located in the center.

12. The gas exchange unit according to claim 10, characterized in that, a. The ventilation device can be selectively switched to a first operating state or a second operating state. In the first operating state, the ventilation device can be flushed; in the second operating state, the cavity of the gas exchange unit can be ventilated. b. The ventilation device can be selectively switched to a first operating state or a second operating state. In the first operating state, ventilation of the cavity of the gas exchange unit cannot be achieved, while in the second operating state, ventilation of the cavity of the gas exchange unit can be achieved.

13. The gas exchange unit according to claim 10, wherein, The ventilation device includes a flexible membrane.

14. The gas exchange unit according to claim 12, characterized in that it has an adjusting element for switching the ventilation device to the first operating condition or the second operating condition.

15. The gas exchange unit according to claim 12, characterized in that, The ventilation device has a sealing piston that can be moved to a first position to achieve the first operating condition or a second position to achieve the second operating condition.

16. The gas exchange unit according to claim 14, characterized in that, The ventilation device has a sealing piston that can be moved to a first position to achieve the first operating condition or a second position to achieve the second operating condition.

17. The gas exchange unit according to claim 15, characterized in that, The closed piston has a fluid line, the fluid line a. Not in fluid connection with the cavity at the first position, but in fluid connection at the second position, and / or b. In the first position, the fluid connection is made with the supply line for supplying the flushing agent, while in the second position, the fluid connection is not made with the supply line.

18. The gas exchange unit according to claim 15, characterized in that, The closed piston a. Installed to move linearly, and / or b. Rotatable mounting, and / or c. The design allows a piston segment to move relative to another piston segment. The position can be moved from the first position to the second position, or vice versa.

19. The gas exchange unit according to claim 15, characterized in that, a. The sealing ring is fitted onto the closed piston, and / or b. The reset element is operatively connected to the closed piston in such a way that the reset element presses the closed piston from the second position to the first position.

20. The gas exchange unit according to claim 16, characterized in that, The closed piston has a weakness, which is designed in such a way that... a. In the second position of the closed piston, the adjusting element passes through the closed piston, and / or b. Ventilation cannot be achieved in the first position of the closed piston.

21. The gas exchange unit according to any one of claims 1, 2, 8, 10 to 20, wherein, The hollow fiber pad is embedded in the gas exchange unit, and the transition from the embedded hollow fiber pad to the adjacent component has an inclined transition section.

22. The gas exchange unit according to any one of claims 8, 10 to 20, characterized in that, The inlet housing has a stabilizer.

23. The gas exchange unit according to claim 1, characterized in that, The gas exchange unit is an oxygenator.

24. A method for producing a gas exchange unit according to any one of claims 1, 2, 8, 10 to 20, 23, the method comprising: A casting is inserted to embed the fiber ends, wherein the insertion is performed once, thereby forming a cylindrical cavity in the central region of the gas exchange unit.

Images