Venous indwelling cannula

Abstract

The invention relates to a venous indwelling cannula (1) for biological application, comprising a venous catheter (2) in which a puncture needle (3) is guided in a longitudinally displaceable manner, at least the portion of the venous catheter (2) provided for placement in the living being is made of a puncture-resistant material or is coated with such a puncture-resistant material over the entire length of the portion or over the main part of the length of the portion in which the puncture needle (3) is guided in a longitudinally displaceable manner.

Description

[0001] This application is a divisional application of the original application with a filing date of March 21, 2019, a national application number of 201980028955.9, and an invention name of “Intravenous Indwelling Cannula”. Technical Field

[0002] The invention relates to an indwelling venous cannula for biological use, the indwelling venous cannula having a venous catheter, wherein a puncture needle can be guided in the venous catheter in a longitudinally displaceable manner. Background Art

[0003] Patent document DE 40 41 720 A1 describes an intravenous cannula with an intravenous catheter and a puncture needle which can be moved therein, wherein the front part of the intravenous catheter which penetrates the body is made of refined steel and the rear part is made of a flexible material such as plastic.

[0004] The disadvantage of such intravenous cannulas is that the flexible part of the intravenous catheter can be easily punctured due to contact with the puncture needle, so these intravenous cannulas must be disposed of. In addition, there is a risk that the flexible part of the intravenous catheter or a part of the flexible part may be cut off due to contact with the puncture needle and remain in the body without being discovered and pose a threat to it. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to provide an improved venous indwelling cannula. The technical problem to be solved by the present invention is also to realize an improved puncture system in the sense of a general puncture system. That is, in principle, it is also possible to advantageously puncture all body cavities and body spaces and all anatomical and pathological structures to be punctured and to place a catheter therein using the improved venous indwelling cannula.

[0006] Although the term "venous cannula" is to be retained below, it has a broad meaning in the sense of a general puncture system that can not only puncture veins. That is, the term "vein" below also includes in principle all body cavities and body spaces that are to be punctured and provided with a catheter and all anatomical and pathological structures.

[0007] Thus, with the intravenous cannula according to the invention, the trachea, pleural cavity, abdominal cavity, intestine, renal pelvis, bladder and bones can be punctured in addition, for example. In addition, pathological structures in and on the organism, such as abscesses, can be punctured.

[0008] Here, the venous cannula can either be removed again directly after puncture or can also remain for a period of time. Advantageously, even arterial vessels can be punctured. Advantageously, aged or calcified arterial vessels can also be punctured, because the new puncture system is more stable than conventional venous cannulas and can therefore also achieve a controlled, possibly ultrasound-controlled advancement against resistance.

[0009] The above technical problem is solved by an intravenous indwelling cannula for use in living beings. Advantageous designs are described in the specification. According to the present invention, the intravenous indwelling cannula has an intravenous catheter and a puncture needle, wherein the puncture needle can be guided in the intravenous catheter in a longitudinally movable manner, and the puncture needle has a tip close to the patient, wherein the intravenous catheter has a spiral structure, and the spiral structure is provided with a sealing coating, and at least the portion of the intravenous catheter that is provided for indwelling in a living being is composed of a puncture-resistant material or coated with such a puncture-resistant material over the entire length of the portion or over the main portion of the length of the portion in which the puncture needle can be guided in a longitudinally movable manner, in such a manner that the spiral structure is designed as a tightly wound helical spring made of a puncture-resistant material, and the puncture-resistant material constitutes the inner wall of the intravenous catheter, wherein the puncture needle is guided through the tightly wound helical spring and when it moves longitudinally in the intravenous catheter. and can be in contact with the tightly wound helical spring, wherein the entire helical structure is surrounded on the outside by a protective layer of plastic of the intravenous catheter, wherein the intravenous catheter is protected from being punctured by the tip of the puncture needle that is close to the patient by the helical structure, wherein the intravenous cannula has at least one retaining element so that it can be more easily applied to the living being, wherein the intravenous cannula has a fixing element designed as a wing, which is configured to fix the intravenous cannula to the living being, wherein the fixing element and the fixing element are combined in a single element, wherein the sealing coating makes the intravenous catheter impermeable to gaseous and / or liquid substances and the sealing coating makes it easier to introduce the intravenous catheter into the punctured body part of the living being.

[0010] According to the present invention, at least the part of the intravenous catheter that is used to be retained in the biological body is composed of a puncture-resistant (or puncture-resistant) material or coated with such a puncture-resistant material (or coated with a puncture-resistant material) over the entire length of the part or the main part of the length below the part, and the puncture needle can be guided longitudinally in this length. Here, the puncture resistance of the material refers to that the intravenous catheter may be punctured by the puncture needle, and this situation should be prevented by the puncture-resistant material. The puncture-resistant material can be a metal, or it can be in the form of a metal alloy, or a corresponding puncture-resistant plastic material or natural material. As plastic materials, for example, carbon fiber reinforced laminates, polymers and / or Teflon can be considered, and they can also be combined with each other. It is advantageous here that the intravenous catheter is not designed too hard (or too rigid) due to the puncture-resistant material, that is, it still has a certain flexibility. In addition, the intravenous catheter can be designed to be MRT (magnetic resonance imaging) / nuclear spin compatible through this material.

[0011] In particular, the puncture-resistant material may no longer be present at the (distal) end of the intravenous catheter that is adjacent to the patient. The thickness and / or material density of the puncture-resistant material need not remain constant over the entire longitudinal extension of the puncture-resistant material present on the intravenous catheter, but may vary over the length. The puncture-resistant material does not necessarily have to be present at all locations. Gaps may be intentionally left in order, for example, to achieve a "predetermined bending position".

[0012] According to the venous indwelling cannula of the present invention, it can be applied in all medical fields, that is to say, not only in the vein area, but also in other anatomical areas of the artery or human or other animal bodies. In addition, the venous indwelling cannula of the present invention should also be able to advantageously puncture technical systems and containers, such as the reservoir of a pump, in the human or other animal body or outside the body. It is conceivable that, for example, the reservoir of an insulin pump and analgesia pump is punctured so as to fill it with an effective substance. It is also conceivable that the puncture of a medical port system. For this reason, the tip of the puncture needle can also be designed into other forms, such as with a trimmed grinding portion, if necessary. The advantage is that the puncture needle is always only used temporarily in the puncture process controlled by the user, and then the venous catheter is advanced by the puncture needle and then the puncture needle can be directly pulled back in a controlled manner. Then, the further steps of the intended application can be safely carried out by the placed, non-pointed venous catheter. Due to the new characteristics of the venous indwelling cannula of the present invention, when the venous catheter is placed in the reservoir, for example, the venous catheter does not bend. Similar to the above content, it is also conceivable that the application field outside medicine. For example, if it is desired to fill the reservoir with a fluid, vapor or gas, the reservoir must be punctured, but then the puncture needle should be immediately and controlledly withdrawn again to avoid damage to the reservoir and to leave only the blunt catheter in the reservoir.

[0013] The present invention has the advantage that the venous indwelling cannula is constructed to be puncture-resistant, kink-resistant and shear-resistant. This minimizes the risk of damage to the venous catheter. Therefore, the venous indwelling cannula can be repeatedly applied to the same organism under permanent sterile conditions (or precautions) after an incorrect puncture, because even when the puncture needle moves multiple times in the longitudinal direction relative to the venous catheter, the venous catheter will not be damaged due to the tip of the puncture needle close to the patient. This is a problem for traditional venous indwelling cannula. In particular, since the flexible venous catheter has been slightly bent due to application, the tip of the puncture needle close to the patient may cause the venous catheter or a part of the venous catheter to be cut off when the puncture needle is repeatedly pushed in the longitudinal direction relative to the venous catheter. This disadvantage of traditional venous indwelling cannula is overcome by the present invention. This improves patient safety. In addition, patient comfort is improved, because in particular, puncture through the skin is very painful and it can be achieved with the venous indwelling cannula according to the present invention that after completing the puncture through the skin, the blood vessel is actively searched multiple times and the part of the venous indwelling cannula close to the patient, in particular the sharp end of the puncture needle close to the patient, is permanently left in the organism below the skin level. This reduces the number of skin punctures required to successfully position an intravenous cannula. This reduces trauma to surrounding tissue. In addition, by reducing the number of skin punctures, the number of possible, potential entry sites for pathogens such as bacteria and viruses through the skin is also reduced.

[0014] Furthermore, the design and improved material properties of the indwelling venous cannula according to the invention make it less likely that the cannula will accidentally move away from the target structure. Due to the more stable and more secure design, the indwelling venous cannula according to the invention is particularly suitable for pressure perfusion.

[0015] Other advantages of the present invention are:

[0016] - The indwelling venous cannula according to the invention achieves reduced pain when placing a venous catheter in a patient, since the indwelling venous cannula according to the invention can be better adapted to the anatomy. Venous irritation and phlebitis can be prevented, since the indwelling venous cannula according to the invention causes significantly less trauma to veins or other blood vessels from the inside, i.e. the vein wall is less irritated.

[0017] - The risk of perforation during the advancement of the intravenous catheter is reduced even in tortuous and / or aged or calcified blood vessels. This is particularly advantageous for fragile blood vessels, elderly patients and special high-risk groups.

[0018] The indwelling venous cannula according to the invention allows the strength of the venous catheter located in the blood vessel to be varied, since a relative movement of the components is possible in all directions.

[0019] The indwelling venous cannula according to the invention helps to avoid puncture errors and thus reduces the risk of infection.

[0020] - Furthermore, the puncture-resistant material provides a higher level of safety against kinking of the intravenous catheter.

[0021] - In addition, by reinforcing the intravenous catheter with puncture-resistant material, possible blockages of the intravenous catheter can also be better suppressed. Blood can be drawn out more easily and more permanently, even repeatedly. In addition, trauma and hemolysis of blood components such as microparticles or red blood cells are suppressed, because the blood turbulence in the intravenous catheter is reduced due to the bending resistance of the intravenous catheter. Compared with existing intravenous catheters, the intravenous catheter has a significantly improved flow behavior overall.

[0022] The puncture-resistant material can be formed, for example, by a tubular metal body or a metal coating of a base material of the intravenous catheter, which base material can be, for example, a plastic material. The metal can be, for example, steel, such as refined steel or titanium, or an alloy or bimetal formed therefrom. In an advantageous embodiment of the present invention, the puncture-resistant material is arranged on the inner side of the intravenous catheter, that is, the puncture-resistant material forms the inner wall of the intravenous catheter. The protective layer of the intravenous catheter surrounding the puncture-resistant material can be formed, for example, of plastic.

[0023] In an alternative design, the puncture-resistant material is arranged on the outside of the intravenous catheter. But it is also conceivable that the puncture-resistant material is arranged on the inside of the intravenous catheter and also on the outside of the intravenous catheter. That is, the puncture-resistant material can constitute the inner wall or outer wall of the intravenous catheter, or can constitute the inner wall and outer wall of the intravenous catheter. In this way, the improved intravenous indwelling sleeve is designed to be more stable and more secure than the intravenous indwelling sleeve known so far while improving the flexibility of the intravenous catheter. Here, the puncture-resistant material is advantageously composed of a material with a non-thrombogenic property. As an alternative or supplement, the puncture-resistant material can be coated with an additional surface, and this surface has a non-thrombogenic property. Thrombosis (blood clot) should be prevented from forming on the intravenous catheter by this material property. The puncture-resistant material can be configured as a metal layer, and can also be configured as a metal alloy (alloy). Furthermore, it is advantageous that the puncture-resistant material is compatible with magnetic resonance imaging (MRI), so that the components of the inserted venous catheter or venous cannula arranged in the body also remain in the body during the MRI examination and do not damage the body during the MRI examination and also cannot become dislocated in the magnetic field.

[0024] All of the above-mentioned layers of the venous cannula advantageously have non-thrombogenic properties. In addition, all of the above-mentioned layers of the venous cannula advantageously have hypoallergenic and / or antibacterial properties. In addition, all of the layers can advantageously be made of a material with very good sliding properties or coated with a material with very good sliding properties. It is clearly possible to modify (or treat) the layers or surfaces with the aid of nanotechnology processes.

[0025] According to the advantageous extended design of the present invention, the part of the intravenous catheter that is arranged to remain outside the body is made of puncture-resistant material or coated with such puncture-resistant material over its entire length or over a large part of its length. In this case, the puncture-resistant material can also be both on the inside and on the outside, or on the inside and on the outside respectively. This can be the same puncture-resistant material as the puncture-resistant material according to the present invention or a different puncture-resistant material. Thus, the puncture resistance can also continue to be maintained in the part of the intravenous indwelling cannula that is arranged outside the patient's body. Thus, the anti-bending property of the part of the intravenous indwelling cannula that is arranged outside the body is also achieved.

[0026] In advantageous extended design, the venous indwelling sleeve is a peripheral venous indwelling sleeve. In addition, advantageously, the venous catheter of the peripheral venous indwelling sleeve has a puncture length of at least 10mm, for example 19mm and a maximum of 200mm, for example 50mm. But the venous catheter of the venous indwelling sleeve can also have a puncture length of up to 80,100,120 or 600mm. Here, the puncture needle and the venous indwelling sleeve are obviously extended overall. Here, the puncture length of the venous catheter is a length consistent with the length of the venous catheter in the organism. The term organism refers to both people and other animals. In particular, the venous indwelling sleeve according to the present invention can be used in the peripheral region because the puncture length is shorter, so that the venous catheter made of puncture-resistant material or the venous catheter equipped with the coating made of puncture-resistant material has no limitations when applied biologically and after being applied biologically relative to traditional venous indwelling sleeves, and puncture protection and cut-off protection are provided at the venous catheter place simultaneously.

[0027] The application range of the venous cannula according to the invention extends to all common venous cannulae in human medicine, including pediatric and veterinary venous cannulae. In particular, however, the venous cannula according to the invention should also allow venous cannulae with a larger diameter than conventional venous cannulae. These venous cannulae can be assigned to a certain inner diameter of the venous catheter, for example, according to the base color, and can be selected by the operator according to the application.

[0028] The intravenous cannula may have at least one holding element in order to make it easier to apply to the living being. Such a holding element may be designed, for example, as a projection of the intravenous cannula, so that the intravenous cannula can be guided by the user with one hand. This makes application easier, because the user can use the other hand, for example, to stabilize the body part of the living being to be punctured or to operate the ultrasound device.

[0029] The venous indwelling cannula can have a fixing element, wherein the fixing element is arranged to fix the venous indwelling cannula on the living being. In this way, it can be achieved that the venous indwelling cannula cannot be accidentally pulled out from the punctured body part of the living being. In addition, it is also made easier to administer the drug, because the venous indwelling cannula remains fixed on the patient and can not be unstable. Here, the venous indwelling cannula can be fixed on the living being by a self-adhesive wound bandage through the fixing element.

[0030] It is conceivable that the fixing element has at least one recess, wherein the recess is provided for a guide wire. The puncture tube can thus be fixed to the living being by means of a fixed suture. Here, a pulling force in the direction of the living being can be applied by means of the suture, thus improving the fixation of the intravenous indwelling cannula.

[0031] It is also conceivable that the functions of the fixing element and the holding element are combined in one single element. Thus, in a first step, the venous cannula can be applied (or placed) by the user via the elements combined in this way, wherein after placement the venous cannula can be fixed to the patient via the combined elements.

[0032] However, a clamping mechanism (klick- / klippmechanismus) for fixing the puncture system on the skin can also be imagined. The clamping mechanism squeezes the tiny skin staple or fixing element in the direction of the skin, so that the skin staple enters the skin or the connective tissue of the organism and is used to reliably fix the venous indwelling cannula. However, the release (or disassembly) of the venous indwelling cannula can be carried out at any time, and the skin staple can be simply pulled out of the organism. If it is necessary to change the position of the venous indwelling cannula or remove the venous indwelling cannula, this process can be repeated at any frequency.

[0033] The intravenous indwelling cannula can have a Y-shaped piece connected in the middle at the end away from the patient, wherein a three-way faucet can be installed on the Y-shaped piece. Here, the three-way faucet can be connected to the protrusion of the Y-shaped piece. But it is also conceivable that the three-way faucet can be directly connected to the Y-shaped piece. This can be done, for example, via a stop element (or a latch element) on the Y-shaped piece, in the form that the three-way faucet can be inserted in the stop element. Here, the Y-shaped piece can be rotatably supported around the longitudinal axis of the Y-shaped piece, so that the Y-shaped piece can be rotated to a favorable position by the user. Here, the separate support of the three-way faucet is also feasible, so that very high flexibility is guaranteed and the best operation is achieved for the user. Here, the three-way faucet can be rotatably supported around the axis of the three-way faucet itself, for example. Advantageously, a filter can also be integrated in the three-way faucet, which can, for example, prevent air, particles or bacteria from entering the organism.

[0034] The venous cannula may have one or more pressure-sensitive valves, which prevent the reverse flow of fluid and the entry of air into the venous catheter and thereby into the patient's body. Such a pressure-sensitive valve may be designed so that it reacts to a certain pressure difference, for example, to the pressure difference between arterial pressure and venous pressure. Such a pressure-sensitive valve may be designed, for example, as a non-return valve.

[0035] The intravenous catheter of the intravenous indwelling sleeve can have a wavy surface. The wavy surface is characterized by the alternating (changing) diameter of the intravenous catheter at least in the cross section along the longitudinal axis of the intravenous catheter. Here, the wave shape can be composed of a sine wave, a rectangular wave, a triangular wave and / or a sawtooth wave, for example. In addition, it is advantageous that the intravenous catheter has a spiral structure and / or is equipped with a spiral structure. Through the spiral structure, the intravenous catheter has greater flexibility, which enables easier application on organisms. Therefore, a intravenous indwelling sleeve is provided, which is designed to be both cut-resistant and puncture-resistant, and also flexible (or flexible).

[0036] The intravenous line can be additionally reinforced with further structures or elements, for example by transversely extending, longitudinally extending or diagonally extending structures or elements, which can also surround or bridge certain sections of the intravenous line and thereby suppress spiral collapse of the intravenous line. These elements can be made of a puncture-resistant material or be constructed with a coating made of a puncture-resistant material.

[0037] The intravenous catheter can be made, for example, from a metal coil like a helical spring, where the individual layers can lie closely against one another so that they touch one another, similar to the structure of a known Seldinger wire made of tightly wound steel wire. The tightly wound layers make the intravenous catheter resistant to cutting and puncture and at the same time flexible.

[0038] By the density of the coil and by the material selection of the intravenous catheter, the desired properties can be achieved according to the application, mainly the desired properties in terms of the flexibility and rigidity of the intravenous catheter. Therefore, high rigidity with higher puncture resistance can be achieved in the tightly wound intravenous catheter. If the intravenous catheter is not too tightly wound, the flexibility is improved. For material selection, a combination of different metals or other puncture-resistant materials can also be used. It is conceivable that the density of the coil can also be adjusted by the user when necessary, in a way that the coiled intravenous catheter can be pulled apart or pressed together. It is also feasible that at different positions of the intravenous catheter, the density of the coil is different as determined by the structural design, and therefore the flexibility and rigidity of the intravenous catheter are changed, especially in the longitudinal extension as determined by the structural design.

[0039] However, it is also conceivable that the intravenous catheter has grooves that are distributed in the circumference, such as a corrugated tube, and these grooves form a wavy surface. In this way, a higher flexibility of the intravenous catheter can be achieved. The grooves extend continuously in the entire circumference of the intravenous catheter and are advantageously arranged in parallel with uniform or uneven spacing on the length of the intravenous catheter. The intravenous catheter has an alternating diameter in this way. In this way, the intravenous catheter can be oriented in different positions. However, it is also conceivable that the grooves can extend in a distributed manner in the circumference in a spiral shape. This spiral groove has the advantage that the pressure loss of the fluid guided through the intravenous catheter is reduced and at the same time, a vortex of the fluid can be achieved.

[0040] Advantageously, the wavy surface is provided with a sealing coating, in particular a plastic coating. It is also advantageous that the coating is a PTFE coating. Here, the sealing coating can be arranged on the outside of the intravenous catheter. Alternatively, the sealing coating can be arranged on the inside of the intravenous catheter. It is also feasible that the sealing coating is arranged as a coating on the inside and outside of the intravenous catheter. In addition, the sealing coating can also be arranged in the wavy surface and thereby seal the surface directly in the area of ​​the wavy surface. The sealing coating makes the intravenous catheter impermeable to gaseous and / or liquid substances. Therefore, for example, the intravenous catheter will not be degassed during suction. At the same time, the coating makes it easier to introduce the intravenous catheter into the punctured body part of the organism.

[0041] The intravenous catheter of the intravenous indwelling cannula may have an expansion body at the end close to the patient for uniformly expanding the punctured body part. This has the advantage that the intravenous catheter can be introduced into the punctured body part of a living being without additionally expanding the puncture site by pushing the expansion body through the intravenous catheter or the expansion body integrated in the intravenous catheter together with the intravenous catheter through the puncture needle into the punctured body part, wherein the necessary expansion is carried out and the intravenous catheter can be pushed further into the body part.

[0042] In the case of a 360° system, the expansion body can end (or taper) at an acute angle of less than 11 degrees. The angle is the angle between two outer expansion surfaces of the expansion body and not the central axis of the expansion body.

[0043] Advantageously, the expansion body can end at an acute angle of less than 10.5 degrees. This has the advantage that the intravenous catheter can be introduced into the punctured body part simply and without additionally enlarging the puncture site, by pushing the expansion body into the punctured body part through the puncture needle, wherein the required expansion is carried out and the intravenous catheter can be pushed into the body part. For this purpose, it is necessary that the expansion body ends at an acute angle of less than 11 degrees, in particular less than 10.5 degrees, so that it can be pushed through the skin during the expansion process. It is conceivable that the expansion body is made of a material that reduces frictional resistance so that the expansion body is easier to push, or is coated with this material. It is also conceivable that after the expansion body has been introduced into the punctured body part, the expansion body is enlarged and the puncture site is enlarged in this way so that the intravenous catheter can be pushed into the punctured body part.

[0044] The intravenous catheter of the intravenous indwelling cannula can have recesses arranged in a circumferential direction at the end close to the patient, which are used to uniformly input the fluid into the organism. This has the advantage that, for example, compared to the case of a conventional intravenous indwelling cannula, the drug can be administered into the organism more uniformly, so that the drug is not concentrated in one part, which is undesirable. In addition, the extraction of blood or other liquids, for example, can be better achieved, and, depending on the respective application, the drainage of secretions or air can also be better achieved.

[0045] Different from the traditional venous indwelling cannula, the venous catheter according to the venous indwelling cannula of the present invention can also have at least two inner chambers separated from each other in addition to the single-lumen design. The puncture needle is guided through one of the inner chambers. This produces a multi-lumen venous indwelling cannula, through which different drugs and solutions separated from each other can be applied simultaneously. By arranging the recess or the discharge port laterally on the venous catheter, the mixing of different drugs and solutions can be avoided. By arranging a plurality of lateral recesses or discharge ports, the flow rate of the applied liquid can also be increased. Pressure perfusion can be advantageously used. Here, the structure of the above-mentioned puncture-resistant material can also be adapted to the presence of the lateral discharge port, for example, surrounding the discharge port in an annular manner, so as to additionally stabilize the discharge port or keep the discharge port open.

[0046] In the multi-chamber design of venous indwelling sleeve, it is feasible that the recess / discharge port can also be arranged on the top and bottom of the intravenous catheter. In a multi-chamber design of venous indwelling sleeve, a plurality of connecting elements for connecting a suction element or a plurality of suction elements are also advantageous. Thus, the position of the venous indwelling sleeve or the intravenous catheter, for example, in the blood vessel can be better controlled, because the different sections of the intravenous catheter can be controlled in its position, for example, in the blood vessel. This has medical importance, for example, when puncturing a deeper blood vessel. If the inner chamber with an opening in the blood vessel near the user is controlled in terms of the reflux of blood, then it can be considered that all other inner chambers also terminate in the blood vessel, because the openings of all other inner chambers are more deeply arranged in the blood vessel. Different openings can also be lined or surrounded with materials visible in the X-ray image, respectively, for accurately controlling the position of the opening, and for accurately controlling the position of the venous indwelling sleeve or the intravenous catheter with this. One or more connecting elements can be arranged on the indwelling venous cannula in such a way that the connecting element points away from the patient's skin at a defined angle, for example at an angle of 90 degrees or at an angle of 45 degrees.

[0047] In one embodiment of a multi-lumen indwelling venous cannula, for example, only the part of the venous catheter in which the puncture needle is guided in a longitudinally displaceable manner can comprise a puncture-resistant material.

[0048] The indwelling venous cannula or the venous catheter can contain or be coated over its entire length or at defined locations with a material that is visible in the X-ray image and thus allows precise position control of the indwelling venous cannula or the venous catheter in the body.

[0049] The intravenous catheter of the intravenous indwelling cannula can have a connecting element for connecting a suction element, such as a syringe. Thus, it is possible to check whether the intravenous catheter is in the target structure of the organism at any time by suction. Therefore, for example, it is possible to verify whether the intravenous catheter of the intravenous indwelling cannula is still in the blood vessel by suctioning blood. In addition, such a connecting element enables simpler administration of medication.

[0050] Advantageously, the puncture needle of the intravenous indwelling cannula is a hollow needle. This hollow needle has just allowed the user to draw blood during and after the puncture, so as to check immediately during and after the puncture whether the corresponding blood vessel has been correctly punctured.

[0051] On the intravenous catheter of the intravenous indwelling sleeve, an expansion body can be arranged, which is used to fix the position of the intravenous catheter in the body part being punctured. This expansion body can for example be configured as an inflatable loop band, i.e. so-called indwelling band (Cuff), which for example is arranged on the outside of the intravenous catheter. The intravenous indwelling sleeve can be sealed outwardly by this indwelling band, in which the indwelling band arranged below the skin is inflated or filled with liquid, and the puncture system is therefore sealed outwardly and is also advantageously fixed in its position.

[0052] The venous indwelling cannula may have a hollow extension element, wherein the hollow extension element can be traversed by a fluid (or can be provided with a fluid flow) in order to reduce thrombosis. If a fluid, such as a saline solution, is traversed through the extension element and the venous catheter with it, a thrombus that would render the venous indwelling cannula unusable can be prevented from forming in the venous catheter.

[0053] However, it is also conceivable to use a stylet arranged in the venous catheter in order to prevent thrombosis.

[0054] The intravenous indwelling cannula may have a safety mechanism, which is arranged to shield the tip of the puncture needle after the puncture needle is removed from the intravenous catheter. This shielding prevents the user or the living being injured by the tip of the puncture needle after the puncture needle is extracted from the intravenous indwelling cannula after the puncture.

[0055] The puncture needle of the intravenous indwelling cannula can be surrounded by a protective cap, which is removed before the intravenous indwelling cannula is used. In this way, undesirable injuries when operating the intravenous indwelling cannula can be avoided.

[0056] With the help of the intravenous cannula, local anesthetics and / or antimicrobial substances can be introduced into the patient's body continuously or in a limited manner in terms of time. For example, it is possible to reduce the pain when inserting or placing the intravenous cannula.

[0057] The intravenous indwelling cannula can have a puncture protection device for the puncture needle. By the puncture protection device, at least in the new state of the intravenous indwelling cannula, it is guaranteed that the user will not be injured by the tip of the puncture needle.

[0058] Depth markings may be provided on the intravenous catheter. The depth of insertion of the catheter into the patient may be controlled by the user via the depth markings. The intravenous catheter may also have a stop ring mounted on the intravenous catheter in order to limit the insertion depth of the catheter to a certain distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The present invention will be further described below with reference to the accompanying drawings according to the embodiments. In the accompanying drawings:

[0060] Figure 1 A schematic side view of an indwelling intravenous cannula is shown. DETAILED DESCRIPTION

[0061] Figure 1 A schematic side view of a venous indwelling cannula 1 is shown. The venous indwelling cannula 1 has a venous catheter 2, wherein a puncture needle 3 can be guided longitudinally in the venous catheter 2. Here, the venous indwelling cannula 1 is configured as a peripheral venous indwelling cannula 1. It can be seen that the venous catheter 2 is made of a puncture-resistant material like a tightly wound spiral spring to produce a wavy surface. Here, the venous catheter 2 is made of a puncture-resistant material over its entire length. The flexibility of the venous catheter 2 is guaranteed by the spiral structure. This design of the venous catheter 2 provides puncture and cut protection, which, for example, protects the venous catheter 2 from being punctured by the tip 6 of the puncture needle 3 close to the patient when the venous indwelling cannula 1 is used. The risk of damage to the venous catheter 2 is minimized in this way. Even if the puncture needle 3 is repeatedly moved relative to the venous catheter 2, the venous catheter 2 will no longer be cut off by the tip 6 of the puncture needle 3 close to the patient. This can greatly reduce the waste caused by damage to the venous catheter. In addition, it can be achieved that the venous indwelling cannula 1 can be used repeatedly in the puncture process under biological conditions of permanent sterility. This is particularly important if an initially incorrect puncture is performed, ie a blood vessel is accidentally missed during the initial puncture or the venous catheter 2 cannot initially be advanced far enough into the blood vessel.

[0062] For better suction, the intravenous catheter 2 is provided with a sealing coating 4. The wavy surface can produce minimal openings that increase the difficulty of suction, because, for example, undesirable air can be sucked in through these openings. The sealing coating 4 can minimize or prevent the undesirable suction of air. Advantageously, the sealing coating 4 is a PTFE coating, which at the same time makes it easier to insert the intravenous catheter 2 into the punctured body part. By means of an additional expansion element 10 located at the end of the intravenous catheter 2 close to the patient, a uniform expansion is achieved when the intravenous catheter 2 is pushed into the punctured body part.

[0063] The biological application of the intravenous indwelling cannula 1 can be carried out, for example, in the following steps:

[0064] 1. Puncture the vein with needle 3

[0065] 2. Push the spiral intravenous catheter 2 with the sealing coating 4 over the tip 6 of the puncture needle 3 close to the patient to the desired position in the vein

[0066] 3. Remove / pull back the puncture needle

[0067] 4. Closing the spiral venous catheter 2 at the end facing away from the patient

[0068] The venous cannula 1 has two retaining elements 5. These retaining elements 5 enable the user to operate the venous cannula 1 with one hand, wherein the second hand can be used, for example, to stabilize the body part to be punctured. The puncture needle 3 is designed as a hollow needle. After puncturing through the tip 6 of the puncture needle 3 close to the patient, the user can immediately know whether the vein has been punctured correctly, in that the venous blood fills the hollow puncture needle 3 and enters the chamber 7, which can thus be directly visible to the user.

[0069] After the puncture is completed, the intravenous catheter 2 can be pushed into the punctured body part and the puncture needle 3 together with the chamber 7 can be immediately pulled out from the part of the intravenous cannula 1 that remains in the body part. The safety mechanism can be designed to cover the tip 6 of the puncture needle 3 that is close to the patient after being pulled out of the intravenous cannula 1, thereby protecting the user and the living being from possible puncture injuries.

[0070] The intravenous catheter 2 can be fixedly held on the living being in its final position in the punctured body part by means of a fixing element 8. The fixing can be performed by means of a self-adhesive wound dressing, which fixes the intravenous cannula 1 on the living being by means of the fixing element 8. The fixing element 8 can be designed, for example, as a wing and is an optional element of the intravenous cannula 1.

[0071] In this case, the puncture needle can extend essentially centrally between the holding element 5 and / or the fixing element 8 .

[0072] It is clear that the functions of the holding element 5 and the fixing element 8 can be integrated in one element. This allows simple production of the venous cannula 1, wherein at the same time the structure of the venous cannula 1 remains simple for the user.

[0073] A suction element, such as a syringe, can be connected via the connecting element 9. In this case, the connecting element 9 can be designed as a valve, which allows simple administration of medication or suction of blood. In this case, the valve prevents liquid, such as blood, from flowing out of the connecting element 9 in the untouched (or unused) state in a reverse direction. In addition, the valve prevents air from entering the connecting element 9 from the outside in the untouched state. In addition, the connecting element 9 can contain a filter, which prevents coarse particles, bacteria and air from entering the interior of the connecting element 9 and thus the interior of the intravenous cannula.

[0074] A suction element, such as a syringe, can be connected to the chamber 7. The intravenous cannula can thus be inserted into the vein while continuously suctioning with the syringe. Therefore, the puncture result can be determined directly and very accurately. Here, the chamber 7 can also be configured as another valve, which allows the flow of fluid only in a certain direction. In addition, alternatively or supplementally, the chamber 7 can also be configured so that the chamber 7 prevents air from entering, or only allows air and other gases and steam to pass in a certain direction. The chamber 7 can be configured, for example, in a manner such as the connecting element 9.

[0075] The chamber 7 and the connecting element 9 can be covered by a protective cover to avoid undesired contamination when the chamber 7 and the connecting element 9 are not in use. Here, the protective cover can be connected to the chamber 7 and / or to the connecting element 9 respectively by a connecting piece.

[0076] The intravenous catheter 2 has recesses 11 arranged in a circumferentially distributed manner at the end near the patient. Through the recesses 11, for example, the uniform release of medicine into the organism can be achieved. Therefore, it is avoided that the medicine is released into the organism in an undesirable local high concentration. By arranging a plurality of recesses 11, the flow rate of the perfusion solution and the medicine applied can also be improved. In addition, it is easier to suck liquid, for example draw blood, through the placed intravenous catheter or through the placed intravenous indwelling cannula. Thus, when other parts of the intravenous indwelling cannula are correspondingly constructed, when these intravenous indwelling cannula are used for drainage fluid, steam and / or gas, for example, in the scope of the puncture of the pleural cavity, other cavities or the above-mentioned body spaces, it is also possible to realize that fluid, steam and / or gas are expected to be spontaneously discharged retrogradely from the intravenous indwelling cannula.

[0077] This view is only a schematic diagram, which reflects a good overview of the components of the intravenous indwelling cannula according to the present invention. However, in practice, the length and size ratios may be different.

[0078] Figure 1What is shown are possible embodiments. Other forms according to the teaching of the invention are also conceivable. In addition, the embodiments of the embodiments are not inseparably linked to one another, so that, for example, the embodiments of the invention are independent of the specifically described embodiments of the embodiments. Therefore, for example, variations in the number, length or size of the individual elements are conceivable at any time.

[0079] List of reference numerals:

[0080] 1- Indwelling intravenous cannula

[0081] 2- Venous catheter

[0082] 3-Puncture needle

[0083] 4-Seal coating

[0084] 5- Holding element

[0085] 6- Tip

[0086] 7-Chamber

[0087] 8-Fixed elements

[0088] 9-Connection elements

[0089] 10-Expansion body

[0090] 11-Concave

Claims

1. A venous indwelling cannula (1) for use in a living being, the venous indwelling cannula having a venous catheter (2) and a puncture needle (3), the puncture needle (3) being guided in the venous catheter (2) in a longitudinally movable manner, characterized in that: The puncture needle (3) has a tip (6) close to the patient, wherein the intravenous catheter (2) has a spiral structure, the spiral structure is provided with a sealing coating (4), at least the part of the intravenous catheter (2) that is arranged to be retained in a living being is composed of a puncture-resistant material or coated with such a puncture-resistant material over the entire length of the part or over a major part of the length of the part in which the puncture needle (3) is guided longitudinally movably, in such a way that the spiral structure is designed as a tightly wound helical spring made of a puncture-resistant material, the puncture-resistant material forming the inner wall of the intravenous catheter, wherein the puncture needle (3) is guided through the tightly wound helical spring when it is longitudinally moved in the intravenous catheter (2) and can engage with the tightly wound helical spring. The invention relates to a spiral spring contact, wherein the entire spiral structure is surrounded on the outside by a protective layer of plastic of the intravenous catheter, wherein the spiral structure protects the intravenous catheter from being punctured by the tip of the puncture needle close to the patient, wherein the intravenous cannula has at least one retaining element to make it easier to apply to the living being, wherein the intravenous cannula (1) has a fixing element designed as a wing, which is provided for fixing the intravenous cannula (1) to the living being, wherein the fixing element and the fixing element are combined in a single element, wherein the sealing coating makes the intravenous catheter impermeable to gaseous and / or liquid substances and the sealing coating makes it easier to introduce the intravenous catheter into the punctured body part of the living being.

2. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The venous indwelling cannula (1) is a peripheral venous indwelling cannula (1).

3. The intravenous indwelling cannula (1) according to claim 2, characterized in that: The venous catheter (2) of the peripheral venous indwelling cannula (1) has a puncture length of 10 mm to 200 mm.

4. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The intravenous catheter (2) has a corrugated surface.

5. The intravenous indwelling cannula (1) according to claim 4, characterized in that: The intravenous catheter (2) has a spiral structure and / or is provided with a spiral structure.

6. The intravenous indwelling cannula (1) according to claim 4 or 5, characterized in that: The corrugated surface is provided with a sealing coating (4).

7. The intravenous indwelling cannula (1) according to claim 6, characterized in that: The corrugated surface is provided with a plastic coating.

8. The intravenous indwelling cannula (1) according to claim 7, characterized in that: The sealing coating (4) is a PTFE coating.

9. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The intravenous catheter (2) has a dilation body (10) at the end close to the patient for uniformly expanding the punctured body part.

10. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The intravenous catheter (2) has a connecting element (9) for connecting a suction element.

11. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The puncture needle (3) is a hollow needle.

12. The intravenous indwelling cannula (1) according to claim 1, characterized in that: An expansion body is arranged on the intravenous catheter (2) for fixing the position of the intravenous catheter (2) in the punctured body part.

13. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The indwelling venous cannula (1) has a hollow extension element, wherein a fluid can flow through the hollow extension element in order to reduce thrombosis.

14. The intravenous indwelling cannula (1) according to claim 1, characterized in that: The intravenous indwelling cannula (1) has a safety mechanism, which is configured to shield the tip (6) of the puncture needle (3) after the puncture needle (3) is removed from the intravenous catheter (2).

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