MEDICAL MEASURING DEVICE AND MEASURING METHODS

Description

[0001] The present invention relates to a medical measuring device for measuring the pressure of a fluid, comprising a line extending along a central longitudinal axis and configured to conduct a fluid, in particular blood, within a longitudinal cavity defined by a wall; and a sensor device having a sensor configured to measure a property of the fluid conducted in the longitudinal cavity. Furthermore, the present invention relates to a method for producing a medical measuring device, comprising the steps of: providing a line having a wall; and arranging a sensor on the line. The present invention particularly relates to a medical measuring device having individual features of claim 1, as well as to a manufacturing method and a measuring method, each having individual features of the independent method claims 15 and 17.

[0002] Measuring devices or sensors are known which are arranged on a connector, adapter or on an intermediate piece between individual sections of a line. The line carries a fluid, in particular an isotonic saline solution or other crystalloid infusion solutions or blood, whose properties, in particular pressure, are to be measured. In such measuring devices there is often a risk of coagulation (or so-called blood clotting) or hemolysis, in particular due to edges, undercuts or transitions with unfavorable flow properties. The connecting elements or connectors also increase the risk of leaks, in particular at interfaces between a connector and an extracorporeal tubing set or in the measuring system, and must be additionally tested. In practice, the problem that leaks can occur, for example, at Luer connectors is particularly well known.Especially with extracorporeal circulation, there is a risk that air may be sucked into an outflow line, where negative pressure may be present, and mixed with the fluid / blood. In an inflow line, where positive pressure may be present, fluid / blood may be forced out of the line through such leaks. The sterility of the entire device can then no longer be guaranteed. The connector or adapter must also be mounted on the line, and a seal, adhesive, or other interface that is as sterile or sterilizable as possible must be ensured.

[0003] As an alternative to measuring devices or sensors coupled or integrated into the line, a measurement, in particular pressure measurement, can also be carried out outside the line. The corresponding sensor can then detect pressure indirectly, e.g. using a water column. With this type of pressure measurement, however, a so-called priming process is required in order to start the pressure measurement. During priming, the hose system is filled with a crystalloid solution such as isotonic saline solution (NaCl), and then the hose system is vented. There is a risk that the line / hose system will be vented incorrectly. During the measurement, there is a risk that fluid / blood penetrating the crystalloid solution in a line leading to a measuring sensor could impair or interrupt the measuring process, which can be life-threatening.

[0004] Another disadvantage of this type of pressure measurement is measurement errors caused by gas inclusions in the water column. Furthermore, the pressure measurement itself can usually only be performed with a delay, as a pressure wave must first be transmitted through the water. Such indirect pressure measurement therefore makes it difficult, for example, to synchronize a pump with the patient's arterial pressure curve.

[0005] The German patent application DE 10 2005 063 410 A1 describes a blood vessel catheter in which a blood pressure sensor is arranged on a housing which is coupled to a catheter tube.

[0006] The German patent application DE 10 2007 038 402 A1 describes a device for detecting a pressure, in which a sensor element is embedded in a pipe wall structure separately from a medium carried in the pipe.

[0007] The European patent EP 0 328 558 B1 describes an elastic hose with a coating applied to the inside in which a pressure signal can be measured when the hose is deformed.

[0008] US Patent 6272930 B1 discloses a device for measuring the pressure of a fluid flowing through a tube. The device includes an elongated body with a first and a second end, an axial bore open toward the ends, and defined by an inner wall. A recess is open toward the axial bore and lies between its two ends. Both ends of the body have connection means for connection to the tube. A pressure sensor is sealed in the recess, the surface of the sensor exposed to the fluid pressure having a shape that is flush with the inner wall of the axial bore in the region of the recess.

[0009] US patent application US 2007 / 0261496 A1 discloses a biological fluid device that includes a pressure sensor arranged on the device. The pressure sensor includes a compressible container whose compression is indicative of the applied pressure.

[0010] It is an object of the present invention to provide a medical measuring device, in particular a blood pressure measuring device, that enables simple handling, especially in conjunction with a comparatively accurate measurement. This object can also be described by the fact that the medical measuring device should have a simple structure and / or minimize the risk of contamination, air inclusions, or leaks.

[0011] The object is achieved by a medical measuring device according to claim 1 for measuring the pressure of a fluid, comprising a line, in particular a hose line, which extends along a central longitudinal axis and is configured to conduct a fluid, in particular blood, within a longitudinal cavity, in particular a cylindrical cavity, which is delimited by a wall; and a sensor device with a sensor, in particular a pressure sensor, which is configured to measure a property of the fluid conducted in the longitudinal cavity; wherein, in the measuring device, it is provided according to the invention that the line has a radial cavity introduced into the wall in the radial direction, in which the sensor device is at least partially arranged and is integrated into the wall in such a way that the sensor is in communication with the fluid in the longitudinal cavity.

[0012] The arrangement of the sensor directly in the wall offers metrological and design advantages. The sensor can be easily positioned in a metrologically preferred position, particularly in the immediate vicinity of a fluid flow path, or even directly in the flow path. In particular, the number of interfaces can be reduced, particularly to just a single interface in the wall. The sensor's integration into the wall eliminates the need for spacers, couplings, or other connections. For example, no Luer connectors or other access to the line are required. This can significantly reduce the risk of leaks or any unsterile interfaces.In contrast, the adapters or connectors most commonly used in the prior art, particularly Luer connectors, always have at least two or three interfaces, namely the interface(s) between the adapter or adapter and the line, and the interface between the adapter or adapter and the sensor. It should therefore be noted that a line within the meaning of the invention is in particular not an adapter, a connector, or an adapter. In addition, incorrect operation of any connections can be avoided. For example, it can be avoided that, for example, in an extracorporeal line system or tube system (such as in dialysis, heart or lung support, or cardiopulmonary bypass in cardiac surgery, or in a catheter or sheath, e.g.in cardiology) in a section with negative pressure (especially with a pressure less than atmospheric pressure) air is drawn into the line / tube system or the catheter in the area of ​​the pressure measuring arrangement, or that in a section with positive pressure (especially where fluid / blood is returned to the body) fluid / blood escapes from the circuit.

[0013] A priming process specifically related to the sensor is no longer required, which can save time and make pressure measurement particularly useful in certain (e.g., life-threatening) situations. Additional supply lines or tubes that need to be vented are no longer required. In other words, the integrated sensor design enables inline measurement without any time delay. The blood-carrying line / tube system (including any catheter or cannula) can be filled and vented independently of pressure measurement.

[0014] Sensors, especially pressure sensors, have become increasingly smaller in recent years. This now allows for advantageous placement of the sensor in the immediate vicinity of the fluid to be measured. The integrated sensor can be positioned directly on the fluid stream without influencing it. This also enables particularly precise (pressure) measurement. For example, integration into a wall with a thickness of only 1 mm to 3 mm is possible.

[0015] Such a sensor arrangement also allows for a largely arbitrary selection of the sensor's position at any section or circumferential position along the line, particularly a hose line. The sensor device or sensor can form part of the wall.

[0016] A measuring device (in particular a pressure measuring device) is preferably understood to be a device that can guide, supply, or discharge a specific fluid in a specific state, in particular in a flow state, and can record and optionally also at least partially evaluate at least one property, in particular the pressure of the fluid. The measuring device can preferably record and evaluate at least the pressure and optionally also other physical or chemical variables. Such a measuring device can be used, for example, for invasive pressure measurement or in conjunction with an extracorporeal circuit, e.g., for renal replacement, for heart-lung support, or for liver support. Especially in the case of an invasive / implanted arrangement, the advantages of good tightness and / or sterility can also result. By means of the measuring device, for example, a patient's vital functions can be monitored, e.g.Heart muscle contractions (hemodynamics), or pressure loss due to extracorporeal circulation can be measured.

[0017] The measuring device can comprise several different sensors. In addition to the sensor, the measuring device can have further components such as a protective cap, a plug socket (e.g. a four-pin plug socket) or a preferably water-repellent membrane, whereby the membrane can ensure protection of the sensor from external influences. The sensor can, for example, operate according to the differential pressure principle. The measuring device then preferably has a connection to the outside air or the environment. The membrane can be attached to a sensor cover above the sensor and protect the sensor, in particular bonded electronic connections of the sensor. The membrane can prevent media (e.g. blood, water, isopropanol) from coming into contact with these connections of the sensor. The membrane is preferably hydrophobic on both sides, i.e. in both directions, whereby air can preferably pass through unhindered.

[0018] A property, in particular a pressure, can also be measured at multiple measurement positions, depending on the medical application, in particular a suction pressure at a first position upstream of a pump, a pump pressure at a second position downstream of the pump, and another at a third position, in particular a reperfusion pressure downstream of a membrane ventilator. In other words, the measuring device can optionally also comprise a plurality of sensor devices or at least a plurality of sensors. Accordingly, the line (including any catheter or cannula present) can also comprise a plurality of radial cavities.

[0019] The term fluid is preferably understood to mean a liquid, but the fluid can also be a gas or at least have gaseous components.

[0020] A line is preferably understood to be any type of line that can be used in connection with medical care, diagnosis or therapy, e.g. also in connection with any catheters. The line can be part of a medical instrument or cutlery. The blood-carrying line in particular can be part of a so-called tubing set or form this tubing set. The (tubing) line can also comprise a cannula to ensure access to the body or can be designed as a cannula in sections. The line is preferably flexible, i.e. elastically formable. In particular, the line can be curved or bent. The elasticity of the line is not affected or not noticeably affected by the sensor device. The diameter of the line can be chosen largely freely. Inner diameters of 3 / 8" or 1 / 4" are particularly suitable.

[0021] The wall or the entire line can be made of a flexible plastic material, particularly polyvinyl chloride (PVC). In the simplest case, the line is, for example, a PVC hose frequently used in medical technology. The plastic material is preferably a high-purity, phthalate-free soft PVC. The wall thickness of the wall and / or line is, for example, in the range of 1 mm to 5 mm, preferably in the range of 1.2 mm to 3.5 mm, more preferably in the range of 1.5 mm to 3 mm, in particular in the range of 1.6 mm to 2.4 mm.

[0022] A sensor device is preferably understood to be a component of the measuring device by means of which a measuring signal, in particular a pressure signal, can be detected and either further processed or at least forwarded.

[0023] A sensor (in particular a pressure sensor) is preferably understood to be a component of the measuring device by means of which a property of a fluid can at least be detected by a measurement signal, in particular a pressure signal. A property or a state of the fluid can be detected, for example, by a physical or chemical variable. A property can be described, for example, by a certain proportion of a gaseous component, e.g. a volume fraction of CO2 or O2. The sensor can be set up, for example, to measure the infusion pressure or injection pressure in fluid-carrying medical products. For example, a piezoresistive sensor can be used. Optionally, sensors based on one or more of the following physical principles or modes of operation can also be used: e.g. piezoelectric, capacitive, inductive, frequency analog, or sensor with Hall element, fiber optic sensor.The sensor can be fitted into the contour of an inner lumen of the line on its surface facing the blood in such a way that a step-free and seamless transition between the sensor and the inner lumen is ensured, in particular to avoid coagulation or hemolysis in the area of ​​the sensor.

[0024] A radial cavity is preferably understood to be a recess, a bore, a cutout, or even a hollowed-out area or section or receiving volume made or provided in the radial direction. The radial cavity can also be formed by a longitudinal cavity extending in the radial direction, which is accessible only from one side of the wall. The radial cavity does not necessarily have to be a passage or a hole in the wall.

[0025] The opening is preferably understood to be a passage or a radial cavity which completely breaks through the wall, i.e. is provided continuously through the wall.

[0026] A recess is preferably understood to be a cavity extending radially from an inner side of the wall, i.e., an inner circumferential surface, which does not necessarily have to extend to an outer circumferential surface of the wall. In other words, the recess is not necessarily a hole in the wall, but can also hollow out the wall only in sections in the radial direction.

[0027] An arrangement "in communication with" is preferably understood to mean an arrangement in which the sensor is in direct contact with the fluid. The sensor can be arranged in the fluid stream, at the side of the fluid stream, or at the side of a flow path of the fluid stream.

[0028] According to one embodiment, the measuring device is configured to connect the sensor device to the line in a single (particularly geometric) interface, in particular by attaching / fixing it directly to an outer surface of the wall and thereby positioning it. This can reduce the risk of leaks, particularly compared to adapters or spacers that have multiple interfaces. In other words, the measuring device only needs to have a single interface or a single attachment point or access point via which the sensor can be integrated into the line.

[0029] The sensor device can be integrated into the line at the sole interface between the sensor device and the line. The interface is preferably formed solely by the radial cavity or by the radial cavity and an outer surface of the wall.

[0030] The interface is preferably understood to be at least one surface at which the sensor device can be connected to the wall. The interface can also comprise different surfaces, which are preferably arranged in the same area of ​​the wall, in particular adjacent to one another.

[0031] According to one embodiment, the sensor is arranged in a radial position between an outer surface and an inner surface of the wall within the wall, spaced from the outer surface, in particular in a section that is closer to the inner surface than to the outer surface. This allows the sensor to be arranged close to the flow path of the fluid or even within the flow path, enabling comparatively precise inline measurement.

[0032] According to one embodiment, the sensor or a radially inwardly projecting free end of the sensor device is arranged at least approximately flush with the inner surface of the wall. This ensures favorable flow conditions. Turbulence caused by undercuts or edges can be largely avoided. This can also reduce the risk of blood clots or hemolysis.

[0033] The sensor can be arranged in a radial position that at least approximately corresponds to a radial distance from an inner surface of the line to the central longitudinal axis in the region of the radial cavity. In other words, the sensor can be arranged in a radial position characterized by a radial distance from the central longitudinal axis corresponding to half the diameter, i.e., the radius of the longitudinal cavity. The sensor can delimit the longitudinal cavity in the radial direction.

[0034] According to one embodiment, the radial cavity is an opening, in particular a cylindrical bore with a uniform diameter. This ensures a particularly simple design. An opening can be easily introduced into the wall at any time and at any position. Furthermore, the sensor can be positioned in the radial cavity from the outside.

[0035] According to one embodiment, an inner surface of the radial cavity is cylindrical or conical or has a polygonal cross-section. The radial cavity is not necessarily round or circular, but can have any cross-section. With a round or cylindrical geometry, the radial cavity can be sealed easily, in particular by means of an interference fit.

[0036] According to the invention, a diameter or an extension of a cross-section of the radial cavity is smaller than a geometrically corresponding section of the sensor device, in particular also of the sensor. This allows the single interface to be sealed largely independently of any material connection. A material connection in the region of the inner surface of the radial cavity is not required. The radial cavity, together with the sensor device and / or the sensor, can form an interference fit, at which the wall can be sealed in a fluid-tight manner. In other words: a corresponding geometry can ensure fluid tightness at the radial cavity between the sensor and the wall, even if no adhesive, glue, or the like is provided at this interface.

[0037] Preferably, the radial cavity is circular. This facilitates a precise arrangement of the sensor device in the radial cavity, particularly independent of a specific rotational position.

[0038] An interference fit is preferably understood to mean an interface in which one of the components to be coupled has a certain allowance, which ensures that the two components to be coupled can only be connected to one another if they are geometrically adapted to one another, and that a play-free and gap-free connection is ensured.

[0039] A diameter or an extension of a cross-section of the radial cavity is, for example, in the range from 1 mm to 5 mm, preferably in the range from 2 mm to 4 mm, more preferably in the range from 2.5 mm to 3.5 mm, in particular in the range from 3 mm to 3.3 mm, especially 3.15 mm. According to one variant, the sensor device then has a radial section which has a diameter or an extension in the range from 1 mm to 5 mm, preferably in the range from 2 mm to 4 mm, more preferably in the range from 2.5 mm to 3.5 mm, in particular in the range from 3 mm to 3.3 mm, especially 3.1 mm, wherein the radial section forms an interference fit, in particular a press fit, with an inner surface of the radial cavity. This allows the radial cavity to be sealed, in particular even without any adhesive in the region of the radial cavity.

[0040] According to a specific embodiment, the wall has an at least approximately constant diameter and / or an at least approximately constant wall thickness. This ensures that the sensor can be positioned in a predefined radial position by means of the sensor device, regardless of the location on the wall where the radial cavity is introduced.

[0041] According to a specific embodiment, the sensor extends at least approximately over the entire cross-sectional profile of the radial cavity and has at least approximately the same extent as a diameter or an extension of the radial cavity. This allows the entire cross-section of the radial cavity to be used for the measurement, in particular for pressure measurement. In other words, the radial cavity can be comparatively small. In particular, the radial cavity can have a diameter that is only as large as, or only slightly larger than, that required for the measurement.

[0042] According to a specific embodiment, the sensor and / or the sensor device has an end face arranged radially flush with an inner surface of the conduit, wherein the end face further develops the wall, in particular over the entire cross-sectional area of ​​the radial cavity. This allows a transition between the inner surface and the radial cavity to be formed, so that undercuts or edges and potentially associated turbulence or dead spaces can be largely avoided. It should also be noted that the sensor does not protrude into the conduit cross-section. According to a specific variant, the end face is designed to correspond geometrically to the geometry of the inner surface, in particular with a concave curve. This allows for a shape-optimized integration. The sensor is not "visible" to the bloodstream. The risk of turbulence can be virtually eliminated.

[0043] According to one embodiment, the sensor device is configured to position the sensor in a predefined radial position in the radial cavity, in particular by the sensor device being configured in a section configured for this purpose to geometrically correspond to an outer circumferential surface of the line / wall. For this purpose, the sensor device can be geometrically configured, at least in sections, such that the sensor device can be positioned in a predetermined relative position directly on the wall. This allows the radial position of the sensor to be predetermined by geometrically designing the sensor device. For example, this can also simplify the installation of the sensor in the "correct" position. The sensor device, for example, only needs to be arranged on the outer circumferential surface, in particular in a longitudinal orientation corresponding to the central longitudinal axis.

[0044] According to the invention, the sensor device has a contact section which, at least in the region of the radial cavity, in particular circumferentially around the radial cavity, is geometrically configured to correspond to an outer surface of the wall. This allows the sensor device to be connected to the line in a simple and robust manner and can be adhered to the line, in particular in the region of the radial cavity circumferentially around the radial cavity. The contact section has, for example, a concave contour which is geometrically configured to correspond to a convex contour of the line or wall.

[0045] The contact section is configured to define the radial position of the sensor, namely, via the outer surface of the wall. In other words, the radial extension of a sensor receptacle or a radial section of the sensor device is matched to the geometry of the contact section in such a way that, when the contact section is placed flat against the outer surface of the wall, the sensor is arranged in a predetermined radial position, particularly within the radial cavity.

[0046] A contact section is understood to be a flat section against which the sensor device can be brought into contact with the line. Preferably, the contact section is also dimensionally stable, i.e., not elastically or plastically deformable, so that relative movement between the line and the contact section in the area of ​​the radial cavity can be avoided. This can ensure a permanent, secure connection between these two components.

[0047] According to the invention, the sensor device is partially arranged in the radial cavity in the wall and integrated into the wall in such a way that the sensor is in communication with the fluid, and that the contact section of the sensor device is designed to encircle the radial cavity and geometrically correspond to an outer surface of the wall.

[0048] The sensor device therefore has one part, namely the sensor or at least part of the sensor, which is located in the radial cavity in the wall of the line, and another part that is arranged on the outside of the line and can be brought into contact with the outer wall of the line via the flat section. The material-to-material connection of the flat section or the contact section of the sensor device around the sensor in the radial cavity ensures optimal sealing of the line to the outside. The fact that the sensor protrudes into the radial cavity not only ensures the material-to-material fixation of the sensor device to the line, but also ensures mechanical fixation, particularly with regard to tensile forces in the direction of the line's longitudinal extension.

[0049] According to one embodiment, the sensor device has a contact section which, at least in the region of the radial cavity, in particular circumferentially around the radial cavity, is integrally connected to an outer surface of the line or wall, in particular by means of an adhesive. This allows the sensor device to be robustly fixed to the line. The integral connection in the region of the outer surface also has the advantage that any adhesive, in particular glue, does not necessarily have to be provided on an inner surface of the radial cavity. This can prevent the fluid, in particular blood, from coming into contact with the adhesive. The adhesive is preferably flexible and moisture-resistant. The adhesive is preferably designed to ensure a permanent adhesive connection to plastic, in particular PVC. The adhesive is preferably a curing adhesive.

[0050] For example, the contact section in the area of ​​the radial cavity is bonded circumferentially to the outer surface using the adhesive, with the sensor device being brought directly into contact with an inner surface of the radial cavity, without adhesive, in a precise and fluid-tight manner. This ensures, on the one hand, a relatively robust, resilient, flat connection between the line and the contact section. On the other hand, it effectively prevents the line from becoming twisted relative to the sensor device.

[0051] It should be noted that arranging the sensor and sensor device exclusively in the radial cavity of a flexible or elastic line can be problematic, as leaks can easily occur if the flexible or elastic line moves or is moved, while the sensor or sensor device, which is a rigid component, is rigidly arranged in the radial cavity and cannot follow this movement. This could lead to leaks in the material connection between the sensor device in the cavity and the line wall.

[0052] According to one embodiment, the sensor device has a radial section in which the sensor is arranged, wherein the radial section preferably has an extension in the radial direction that is preferably greater than half a wall thickness of the wall in a section in which the radial cavity is arranged. As a result, the sensor can be arranged in a predefined position in the radial cavity by means of the radial section, in particular in a comparatively precise manner in a precisely predeterminable radial position, e.g., exactly at the level of the inner circumferential surface of the wall. According to one variant, the radial extension can correspond at least approximately to the wall thickness, so that the sensor can be positioned almost in the flow path of the fluid, i.e., at least approximately at the same radial distance from a central longitudinal axis of the line as the inner circumferential surface of the wall. The radial section can be adapted to the wall thickness.In other words: The position of the sensor can be specified / defined by a predetermined radial extension of the radial section.

[0053] A radial section is preferably understood to be a section extending in the radial direction, which is configured to be coupled to the radial cavity and which has a cross-sectional shape which geometrically corresponds to the cross-sectional profile of the radial cavity. The radial section can comprise a sensor receptacle which is configured to hold or fasten the sensor to the sensor device. A sensor receptacle is preferably understood to be a part of the sensor device on which the sensor (or a very specific type of sensor) can be positioned on the sensor device, provided that the sensor is not integrated into the sensor device or formed by the sensor device. The sensor receptacle can, for example, also have electrical contacts by means of which the sensor is electrically connected to a cable or any communication interface or power supply.The radial section can also be formed at least in sections by the sensor holder.

[0054] According to one embodiment, the sensor device, or at least one or more of the radial sections of the sensor device, is formed from a plastic material. This provides an interface to the wall, which can also be effectively sealed, particularly in the case of PVC hoses. A contact section of the sensor device can also be effectively connected to the wall (advantageous material pairing).

[0055] According to one embodiment, the measuring device is a disposable device intended for single use, wherein the sensor device preferably has a coupling point for communication and / or power supply, in particular for wired transmission via a cable or for wireless transmission. The integration of the sensor into the wall enables a simply constructed measuring device in which, for example, only a cable or a stick needs to be removed before the measuring device is disposed of.

[0056] According to one embodiment, a measuring system for extracorporeal circulation can be formed with at least two measuring devices according to the invention, wherein one of the measuring devices has an inlet line and another of the measuring devices has an outlet line. This allows both a property, in particular a pressure of a discharged fluid and a supply fluid, to be measured in a circuit. In the outlet line, the risk of air being drawn into the line (especially at any Luer connectors) can be reduced. In the supply line, the risk of fluid (especially blood) being forced out of the line or spraying out in the event of excess pressure (especially at any Luer connectors) can be reduced. In other words: integrating the sensors into the wall offers the advantage that leaks can be largely eliminated.The number of interfaces can be reduced, in particular to a single interface per line.

[0057] The object is also achieved by a method according to claim 15 for producing a medical measuring device according to the invention, comprising the steps: Providing a line with a wall, in particular a flexible, bendable hose line; arranging a sensor on the line; in which it is provided according to the invention that a radial cavity is introduced into the wall in the radial direction and the sensor is arranged in the radial cavity, in particular at a radial position between an outer surface and an inner surface of the wall, spaced from the outer surface. This results in the advantages explained in connection with the measuring device.

[0058] According to one embodiment of the method, the measuring device is integrally connected to an outer surface of the wall and / or the sensor is positioned fluid-tight in the radial cavity with an interference fit in the wall. This makes it possible to provide a measuring device that has a single, comparatively robust and resilient interface that can be sealed fluid-tight with a high degree of reliability. Sealing preferably occurs solely in the radial cavity, and the unambiguous relative position can preferably be ensured by the integral connection. A integral connection can increase robustness.

[0059] The object is also achieved by a method according to claim 17 for pressure measurement by means of a medical measuring device according to the invention, comprising the steps: Conducting a fluid, in particular blood, through a line within a longitudinal cavity defined by a wall, in particular through a hose line; measuring the pressure of the fluid by means of a sensor of the measuring device; In which, according to the invention, the sensor is positioned in a radial cavity formed in the wall, and the property is measured in the radial cavity, in particular at a radial position between an outer surface and an inner surface of the wall, spaced from the outer surface. The measurement, in particular the pressure measurement, can be performed "inline" within the wall. The integrated arrangement of the sensor enables "inline" measurement without any time delay.

[0060] The invention is explained in more detail using exemplary embodiments in the following drawing figures. They show: Figure 1in a schematic representation in perspective view a line of a medical measuring device according to an embodiment of the invention; Figure 2 in schematic representation in perspective view a sensor device of a medical measuring device according to an embodiment of the invention in an arrangement on the in the Fig. 1 shown line; Figure 3 in a schematic representation in a sectional view of a medical measuring device according to an embodiment of the invention; Figures 4 and 5 each in schematic representation in different perspective, sectional views which are shown in the Figure 3 medical measuring device shown; and Figure 6 in schematic representation in a side view a sensor device of a medical measuring device according to an embodiment of the invention.

[0061] In connection with the description of the following figures, reference symbols that are not explicitly explained refer to the embodiment of the Figure 1 referred to.

[0062] In the Figure 1a line 20 in the form of a hose line is shown, which has a wall 22. The line 20 can be made of an elastic material and can be flexible or bendable. The wall 22 has an outer surface 22.1 and an inner surface 22.2. The wall 22 or the inner surface 22.2 defines a longitudinal cavity 24, in which a fluid, in particular blood, can be guided. The line 20 extends longitudinally along a central longitudinal axis M. In the radial direction r, a radial cavity 26 is introduced into the wall 22. The radial cavity 26 is a radial opening in the form of a hole, which extends from the outer surface 22.1 to the inner surface 22.2 and forms a passage. A sensor or a sensor device can now be positioned in this passage, and sealing can be achieved by means of the sensor or the sensor device, as explained in connection with the following figures.

[0063] In the Figure 2 a medical measuring device 10 is shown, which in Figure 1described line 20 and a sensor device 30. A sensor 32 is arranged in or on the sensor device 30. The sensor 32 can be understood as a component of the sensor device 30. The sensor 32 or at least partially also the sensor device 30 is arranged in the radial cavity 26, wherein the sensor 32 is positioned between the outer circumferential surface 22.1 and the inner circumferential surface 22.2. The sensor device 30 has a radial section 36 extending in the radial direction and a contact section 38 extending in the longitudinal direction. The radial section 36 comprises a sensor receptacle 34 in which the sensor 32 is arranged. The sensor receptacle 34 and / or the sensor 32 are designed to correspond geometrically to the radial cavity 26. The contact section 38 comes into contact with the outer circumferential surface 22.1, in particular in a planar manner surrounding the radial cavity 26.

[0064] The Figure 3shows a medical measuring system 1, which, among other things, Figure 2 illustrated medical measuring device 10 and an overmolding 9 with a passage 9.1, wherein the sensor 32 is in communication with the environment U via the passage 9.1. The sensor 32 is covered by a cover 14 and protected by an air-permeable, water-repellent membrane 16. In the Figure 3It is shown in detail that the radial section 36 lies precisely flat against an inner surface 26.1 of the radial cavity 26, in particular circumferentially, in order to ensure sealing of the longitudinal cavity. The contact section 38, on the other hand, only contacts the outer circumferential surface 22.1, specifically directly in certain sections and / or optionally (as indicated) indirectly via an adhesive 12. The adhesive 12 is preferably provided completely circumferentially around the radial cavity 26 on the outer circumferential surface 22.1 and / or the contact section. However, the adhesive 12 is not provided on the inner surface 26.1, in particular in order to avoid contact with the fluid guided in the longitudinal cavity.

[0065] The radial position of the sensor 32 is determined by the Figure 3explained only as an example. The radial position of the sensor 32 may deviate from the position shown. In particular, the sensor 32 may be arranged further inward, closer to the inner surface 22.2, which can provide advantages in many applications, e.g., the advantages of direct "inline" measurement in the flow path, i.e., at least almost without the influence of any flow turbulence at any undercuts or edges.

[0066] The wall 22 has a wall thickness r22, which is, for example, in the range of 1 mm to 5 mm, in particular in the range of 1.6 mm to 2.4 mm. The radial position of the sensor 32 is at least approximately central with respect to the outer and inner circumferential surfaces 22.1, 22.2. However, the radial section 36 can have a greater radial extent than shown. In particular, the radial section 36 can have a radial extent that is in the range of the wall thickness r22.

[0067] In the Figures 4 and5 Further components of the measuring system 1 are shown, in particular a plug socket 5, which provides a coupling point for communication and / or power supply, and a button 7 for manually actuating the measuring system 1. The plug socket 5 is connected to the sensor device 30 and the sensor 32 by means of an adapter cable 3, which is arranged in the overmolding 9.

[0068] The Figure 5The connector socket 5 shown is designed to accommodate either a plug in conjunction with an (external) cable or a type of "stick" or module. The stick can ensure wireless communication, e.g., via WLAN, radio, or Bluetooth. The stick can also have a power supply, e.g., a battery. The connector socket 5 can have the same shape for both variants, so that a user can decide whether a wired power supply and communication is desired, or whether the communication should be wireless and the power supply via the stick, e.g., using batteries integrated into the stick. Both the cable and the stick can be used multiple times. In other words, the medical measuring system 1 or the medical measuring device 10 can be intended for single use ("disposable"), and the cable or stick can then be disconnected from the connector socket before disposal.

[0069] In the Figure 6 a medical measuring device 10 is shown, which is comparable to the one in the Figure 2 shown sensor device 30. In this sensor device 30, the extension of the radial section 36 is matched to the wall thickness of the wall 22 such that the sensor 32 is arranged flush with the inner surface 22.2. List of reference symbols

[0070] 1Medical measuring system, in particular pressure measuring system 3Adapter cable 5Connector socket 7Button 9Overmolding 9.1Passage in overmolding 10Medical measuring device 12Adhesive, in particular glue 14Cover, in particular protective cap 16Membrane 20Line, in particular hose line 22Wall 22.1Outer surface of the wall 22.2Inner surface of the wall 24Longitudinal cavity 26Radial cavity, in particular radial opening 26.1Inner surface of the radial cavity 30Sensor device, in particular pressure sensor device 32Sensor, in particular pressure sensor 34Sensor receptacle 36Radial section 38System section MCenter longitudinal axis rradial direction r22Wall thickness

Claims

1. Medico-technical measuring device (10) for pressure measurement, comprising - a line (20) which extends along a central longitudinal axis (M) and is configured to guide a fluid, in particular blood, within a longitudinal cavity (24) delimited by a wall (22); - a sensor unit (30) with a pressure sensor (32), which is configured to measure the present of the fluid guided in the longitudinal cavity (24); and another wherein the sensor unit (30) has an abutting section (38), which abuts against the external sleeve surface (22.1) of the wall (22) and has a radial section (36), wherein the line (20) has a radial cavity (26) introduced in the wall (22) in a radial direction, in which cavity the sensor unit (30) is at least partially arranged and is integrated in the wall (22), such that the pressure sensor (32) is in communication with the fluid, wherein a diameter or an extent of a cross section of the radial cavity (26) is smaller than a section of the sensor unit (30) that corresponds geometrically thereto.

2. Measuring device (10) according to claim 1, wherein the measuring device (10) is configured to connect the sensor unit (30) in a single interface with the line (20), in particular to attach it directly to an external sleeve surface of the wall.

3. Measuring device (10) according to one of the previous claims, wherein the sensor (32) is arranged in a radial position between an / the external sleeve surface (22.1) and an internal sleeve surface (22.2) of the wall inside the wall distanced from the external sleeve surface, in particular in a section which is arranged closer to the internal sleeve surface than to the external sleeve surface.

4. Measuring device (10) according to one of the previous claims, wherein the radial cavity (26) is an opening, in particular a cylindrical bore with a uniform diameter.

5. Measuring device (10) according to one of the previous claims, wherein the radial cavity, together with the sensor unit and / or the sensor (32), forms an oversize fit to which the wall (22) can be sealed in a fluid-tight manner.

6. Measuring device (10) according to one of the previous claims, wherein the sensor unit (30) is configured to position the sensor (32) in a predefined radial position in the radial cavity (26).

7. Measuring device (10) according to one of the previous claims, wherein the sensor unit (30) has an abutting section (38) which is designed to geometrically correspond to an / the external sleeve surface (22.1) of the wall (22), at least in the area of the radial cavity (26), in particular circumferentially around the radial cavity.

8. Measuring device (10) according to claim 7, wherein the sensor unit (30) is partially arranged in the radial cavity (26) in the wall (22) and integrated in the wall (22) such that the sensor (32) is in communication with the fluid and such that the abutting section (38) of the sensor unit (30) is designed circumferentially around the radial cavity (26) and to geometrically correspond to an / the external sleeve surface (22.1) of the wall (22).

9. Measuring device (10) according to one of the previous claims, wherein an / the abutting section (38) of the sensor unit (30) in the area of the radial cavity (26), in particular circumferentially around the radial cavity, is connected by a substance-to-substance bond with an / the external sleeve surface (22.1) of the wall (22), in particular by means of an adhesive agent (12).

10. Measuring device (10) according to one of the previous claims, wherein the sensor unit (30) has a radial section (36) in which the sensor (32) is arranged, wherein the radial section preferably has an extension in a radial direction, which is preferably larger than half of a wall thickness (r22) of the wall (22) in a section in which the radial cavity (26) is arranged.

11. Measuring device (10) according to one of the previous claims, wherein the sensor unit (30), at least partially, in particular at least a / the radial section (36) of the sensor unit, is made from a plastic material.

12. Measuring device (10) according to one of the previous claims characterized in that the measuring device (10) is a disposable device provided for one-time use.

13. Measuring device (10) according to one of the previous claims, wherein the sensor unit (30) has a coupling point for a communication and / or energy supply, in particular for a transmission by wire over a cable or for a wireless transmission.

14. Measuring system (1) for extra-corporeal circulation with at least two measuring devices (10) according to one of the previous claims, wherein one of the measuring devices has a feed line (20), and another of the measuring devices has a discharge line (20).

15. Method for producing a medico-technical measuring device (10) according to one of the previous claims 1 to 13 comprising the steps: - providing a line (20) with a wall (22) in particular as a flexible, pliable hose line; and - arranging a sensor (32) at the line (20); characterized in that a radial cavity (26) is inserted in the wall (22) in a radial direction, and the sensor (32) is arranged in the radial cavity (26), in particular at a radial position between the external sleeve surface (22.1) and the internal sleeve surface (22.2) of the wall.

16. Method according to claim 15, wherein the measuring device (10) is connected by a substance-to-substance bond with an / the external sleeve surface (22.1) of the wall (22) and / or the sensor (32) in the radial cavity (26) is positioned by an oversize fit in a fluid-tight manner in the wall.

17. Method for measuring the pressure of a fluid by means of a medico-technical measuring device (10) according to one of claims 1 to 13, comprising the steps: - guiding a fluid, in particular blood, through a line (20) within a longitudinal cavity (24) delimited by a wall (22); and - measuring the pressure of the fluid by means of a pressure sensor (32) of the measuring device; characterized in that the pressure is measured in a radial cavity (26) inserted in the wall in which the sensor (32) is positioned, in particular in a radial position between an external sleeve surface (22.1) and an internal sleeve surface (22.2) of the wall distanced from the external sleeve surface, preferably in a radial position closer to the internal sleeve surface than to the external sleeve surface.