Patent Application
20230102704
The present invention relates to a device for percutaneous dilational tracheostomy, wherein the device comprises a puncture needle, a guide catheter, and a guidewire. The present invention also includes a set comprising the device according to the invention for percutaneous dilational tracheostomy, as well as a dilator for expanding the tracheostoma and, as further components, optionally a scalpel, a predilator, an insertion aid for the guidewire, a reinforcement catheter with a safety lock for the guidewire, a set of compresses and/or a syringe.
Percutaneous dilatative tracheostomy is a method of inserting a tracheostomy tube into a patient's windpipe. As an alternative to the surgical method, the trachea is initially accessed here using an over-the-needle catheter. This typically takes place between the 2nd and the 3rd or the 3rd and the 4th tracheal ring.
The individual components necessary for percutaneous dilatative tracheostomy are typically provided in coordinated sets, which, in addition to the over-the-needle catheter, also include other components that can be used in the procedure, such as a scalpel, a predilator, a dilator, a guidewire, an insertion aid for the guidewire, a reinforcement catheter with a safety lock for the guidewire, a set of compresses and/or a syringe.
Over-the-needle catheters consist of a hollow, sharpened steel puncture needle surrounded by a tight-fitting plastic guide catheter. The needle and the catheter both often each have a connector, such as a female Luer connector, at the proximal end facing away from the patient. The puncture needle provides sufficient strength to the guide catheter so that it can be inserted into the patient.
After the over-the-needle catheter has been inserted, the puncture needle is pulled out of the guide catheter remaining in the patient, so that a guidewire, the so-called Seldinger wire, can then be inserted into the trachea through the guide catheter. The guidewire serves as a guide rail during dilatation with dedicated dilators and during the subsequent insertion of the tracheostomy tube. This minimizes the risk of tracheal wall injuries and ensures that the dilators and the tracheostomy tube are actually inserted into the trachea and do not accidentally end up in the via falsa.
After the puncture needle has been pulled out of the guide catheter, there is a risk that the guide catheter remaining in the patient will kink. This can happen easily, particularly if the user tries to change the position or angle of the catheter relative to the position of the trachea after removing the stabilizing puncture needle. Once the guide catheter is kinked, it is often no longer possible to pass the guidewire through the guide catheter because the kink is a constriction through which the guidewire cannot be pushed.
This situation often cannot be fixed even by reinserting the already removed puncture needle, because this can easily lead to the guide catheter being punctured by the reinserted cannula. In many cases, therefore, the puncture procedure is repeated again with a new over-the-needle catheter, and, if no suitable individual components are available to do this, a new tracheostomy set will frequently be opened, which of course involves additional consumption costs.
To solve the above-described problem, the present invention proposes a device for percutaneous dilational tracheostomy which comprises a puncture needle, a guide catheter and a guidewire, wherein the puncture needle has a ground tip at its distal end, wherein the maximum outer diameter of the puncture needle is smaller than the minimum inner diameter of the guide catheter, and wherein the puncture needle can be inserted so far into the guide catheter that the ground tip of the puncture needle projects beyond the distal end of the guide catheter, wherein the device according to the invention is in particular characterised in that the maximum diameter of the guidewire is smaller than the minimum inner diameter of the puncture needle, so that the guidewire can be passed through the puncture needle such that its end projects beyond the ground tip of the puncture needle.
The advantage of the present invention is that the cross-sections of the puncture needle, the guide catheter and the guidewire are sized such that the guidewire can be passed through the puncture needle disposed in the guide catheter. It is therefore no longer necessary to pull out the puncture needle after the insertion of the guide catheter into the trachea in order to be able to insert the guidewire. When using the device according to the invention, there is consequently also no risk of the catheter kinking, because the catheter is also stabilised by the puncture needle during the insertion of the guidewire.
This advantage cannot be achieved with conventional tracheostomy devices, because the inner diameter of the guide catheter in said devices is just large enough to pass the guidewire through. On the other hand, in conventional tracheostomy devices, the inner diameter of the guide catheter is as small as possible in order to have the overall smallest possible cross-section for the puncture.
For the aforementioned reasons, the inner diameter of the guide catheter in conventional tracheostomy devices is about 0.1 to 0.4 mm larger than the outer diameter of the guidewire. As a result, the outer diameter of the guidewire is larger than the inner diameter of the puncture needle in conventional tracheostomy devices. Therefore, in conventional tracheostomy devices, it is not possible to push the guidewire through the puncture needle.
In contrast, in the present invention, the guide catheter and the puncture needle are dimensioned such that the guidewire can be passed through the puncture needle. For this purpose, in some embodiments of the invention, the guidewire has a maximum diameter in the range of 1.0 to 1.5 mm, preferably in the range of 1.2 to 1.3 mm. In certain embodiments, the minimum inner diameter of the puncture needle is 0.1 to 0.4 mm larger than the maximum diameter of the guidewire. In specific embodiments, the minimum inner diameter of the puncture needle is 0.2 to 0.4 mm larger than the maximum diameter of the guidewire. In certain embodiments of the invention, the minimum inner diameter of the guide catheter is 0.05 to 0.3 mm larger than the maximum outer diameter of the puncture needle. In specific embodiments, the minimum inner diameter of the guide catheter is 0.05 to 0.15 mm larger than the maximum diameter of the puncture needle.
The puncture needle consists of a hollow needle having a ground tip at its distal end. A connector is preferably disposed at the proximal end of the hollow needle. The guide catheter consists of a guide tube, which is preferably tapered at its distal end. A connector is also optionally disposed at the proximal end of the guide tube. The available connectors are suitable for connection to a conventional medical tube system (e.g., female Luer connector).
In the context of the present invention, the terms “distal” and “proximal” are used from the perspective of a physician using the tracheostomy device; i.e., the proximal end of the puncture needle is the end which remains outside the patient's body after the puncture, while the distal end is inserted through the skin into the patient's trachea during the puncture.
The ground tip of the puncture needle preferably projects 1 to 10 mm, particularly preferably 2 to 6 mm, beyond the distal end of the guide catheter. The lengths of the hollow needle and the catheter tube, and, if necessary, the position and configuration of the connectors on the puncture needle and the guide catheter, are selected accordingly for this purpose.
The hollow needle of the puncture needle preferably has a length in the range of 4 cm to 9 cm. The maximum outer diameter of the hollow needle is preferably in the range of 1.3 to 2.1 mm. In certain embodiments, the maximum outer diameter of the hollow needle is in the range of 1.5 to 2.0 mm. The minimum inner diameter of the hollow needle is preferably in the range of 1.1 to 1.9 mm. In certain embodiments, the minimum inner diameter of the hollow needle is in the range of 1.2 to 1.8 mm. The wall thickness of the hollow needle is preferably in the range of 0.1 to 0.2 mm.
The catheter tube of the guide catheter preferably has a length in the range of 3 cm to 8 cm. The maximum outer diameter of the catheter tube is preferably in the range of 1.5 to 2.5 mm. In certain embodiments, the maximum outer diameter of the catheter tube is in the range of 1.6 to 2.3 mm. The minimum inner diameter of the catheter tube is preferably in the range of 1.4 to 2.1 mm. In certain embodiments, the minimum inner diameter of the catheter tube is in the range of 1.6 to 1.9 mm. The wall thickness of the catheter tube of the guide catheter is preferably in the range of 0.1 to 0.2 mm.
In preferred embodiments, the hollow needle of the puncture needle is made of metal, particularly preferably of steel. The guide tube of the guide catheter is preferably made of plastic, preferably FEP (fluorinated ethylene propylene). The available connectors on the puncture needle and/or the guide catheter are likewise preferably made of plastic. In particularly preferred embodiments, the guide tube and a connector disposed upon it are integrally formed from a plastic material.
The plastic of the guide tube can consist of either a transparent or non-transparent plastic material, optionally with one or more white or coloured longitudinal stripes to facilitate endoscopic position control. In certain embodiments, the plastic material of the guide tube contains an X-ray contrast agent (e.g., barium sulphate).
In certain embodiments, in which connectors are disposed at the proximal end of the puncture needle and the guide catheter, the connector on the puncture needle is disposed in the connector on the guide catheter in a first stable insertion position such that the ground tip of the puncture needle projects 1 to 10 mm, particularly preferably 2 to 6 mm, beyond the distal end of the guide catheter. In these embodiments, the puncture needle can preferably be brought into a second stable insertion position, in which the ground tip no longer projects beyond the guide catheter, by turning or pulling on the connector of the puncture needle.
In order to bring the puncture needle into a second stable insertion position in which the ground tip does not project beyond the guide catheter by turning, some embodiments comprise an internal or external thread disposed on the inner wall of the guide catheter connector and a corresponding external or internal thread disposed on the outer wall of the puncture needle connector. Alternatively, an internal thread is disposed on the inner wall of the guide catheter connector or on the outer wall of the puncture needle connector and a projecting web or a projecting lug that can engage with the thread located on the other wall is disposed on the respective other wall (outer wall of the guide catheter connector or the inner wall of the puncture needle connector).
The coordinated geometry of the thread(s) or webs/lugs preferably defines at least two different latching positions, wherein the ground tip of the puncture needle is stably held projecting 1 to 10 mm, particularly preferably 2 to 6 mm, beyond the distal end of the guide catheter in a first latching position, and wherein the ground tip of the puncture needle does not project beyond the guide catheter in a second latching position.
The guidewire is preferably made of metal or plastic. A preferred metal for the guidewire is steel, nitinol, or a combination thereof. The embodiments with metal wire preferably have a plastic coating on the metal wire. In certain embodiments, the material of the plastic coating is Teflon (polytetrafluoroethylene) or FEP (fluorinated ethylene propylene). Certain embodiments are characterised in that the end of the guidewire which projects beyond the end of the puncture needle when passed through the puncture needle is curved in a quarter to three-quarter circle. This type of guidewire is often referred to as a guidewire.
To facilitate insertion of the guidewire, in certain embodiments, the lumen of the hollow needle of the puncture needle widens in a funnel shape in proximal direction at the end of the puncture needle opposite to the ground tip.
In embodiments comprising a connector at the proximal end of the puncture needle, the lumen of the connector preferably tapers in a funnel shape in the direction of the lumen of the puncture needle to facilitate insertion of the guidewire into the hollow needle. The inner wall of the connector at the proximal end of the hollow needle is particularly preferably flush with the hollow needle opening.
In an alternative embodiment, in which the lumen of a connector at the proximal end of the puncture needle is substantially cylindrical, an adapter is preferably disposed in a precisely fitting manner in the lumen of the connector, whereby the adapter itself comprises a lumen that tapers in a funnel shape in the direction of the lumen of the puncture needle to facilitate insertion of the guidewire into the hollow needle. The inner wall of the adapter inserted into the connector at the proximal end of the hollow needle is particularly preferably flush with the hollow needle opening.
The present invention relates to a device for percutaneous dilational tracheostomy, wherein the device comprises a puncture needle, a guide catheter, and a guidewire. In certain embodiments, this device is part of a set for percutaneous dilational tracheostomy which further comprises a dilator for expanding the tracheostoma. Such a dilator comprises a dilatation region having a diameter which increases continuously in longitudinal direction, and, in certain embodiments, a guide channel is provided in longitudinal direction in the dilator, the minimum inner diameter of which is larger than the maximum diameter of the guidewire, so that the guidewire can be passed through the guide channel.
In the dilatation region, the outer diameter of the dilator preferably increases to up to 1.2 to 1.5 cm. In preferred embodiments, the minimum inner diameter of the guide channel of the dilator is in the range of 1.0 to 3.0 mm.
In certain embodiments of the set according to the invention, said set additionally comprises a scalpel, a predilator, an insertion aid for the guidewire, a set of compresses, a reinforcement catheter with a safety lock for the guidewire and/or a syringe, as well as optionally a tracheostomy tube and or insertion aids for inserting a tracheostomy tube.
In the embodiments of the set comprising a predilator for expanding the tracheostoma, said predilator has an outer diameter which is larger than the outer diameter of the guide catheter and smaller than the average outer diameter of the dilator, wherein a guide channel is provided in longitudinal direction in the predilator, the minimum inner diameter of which is larger than the maximum diameter of the guidewire, so that the guidewire can be passed through the guide channel, wherein the minimum inner diameter of the guide channel of the predilator is 0.1 to 1.0 mm larger than the maximum diameter of the guidewire.
In the embodiments of the set comprising a reinforcement catheter, said reinforcement catheter has an outer diameter that is smaller than the minimum inner diameter of the dilator, so that the reinforcement catheter can be passed through the guide channel of the dilator. The minimum inner diameter of the reinforcement catheter is larger than the maximum diameter of the guidewire, so that the guidewire can be passed through the reinforcement catheter, wherein the minimum inner diameter of the reinforcement catheter is 0.1 to 1.0 mm larger than the maximum diameter of the guidewire.
In the embodiments of the guidewire comprising an insertion aid for the guidewire, the insertion aid for the guidewire is preferably disposed at the end of the guidewire which projects beyond the end of the puncture needle when passed through the puncture needle, wherein the insertion aid comprises a guide channel in longitudinal direction and centrally, the minimum inner diameter of which is larger than the maximum diameter of the guidewire, so that the guidewire can be passed through the central guide channel, wherein one end of the guide channel opens into a conically tapering section of the insertion aid. This conically tapering portion of the insertion aid is sized and shaped such that this portion can be inserted into the proximal end of the puncture needle with or without a connector or with or without an adapter to facilitate insertion of the guidewire into the hollow needle.
For the purpose of the original disclosure, it should be noted that all of the features as they become apparent to a person skilled in the art from the present description, the drawings and the claims, even if they have been specifically described only in connection with specific other features, can be combined both individually and in any combination with other features or groups of features disclosed here, insofar as this has not been expressly excluded or technical circumstances make such combinations impossible or pointless. A comprehensive, explicit presentation of all conceivable combinations of features is omitted here solely for the sake of brevity and legibility of the description.
Individual examples of the aforementioned specific embodiments of the invention are provided with reference to the appended
The following features or combinations of features are shown in detail in the above-mentioned figures.
The guide catheter 5 shown here also consists of two subunits, namely the catheter tube 6 and the catheter connector 7. In the plastic embodiment shown here, the catheter tube and the catheter connector are made in one piece of plastic, so that the plastic material widens conically from the transition from the catheter tube 6 to the catheter connector 7 to then transition in proximal direction into a cylindrical portion.
The guidewire 8 is shown here considerably shortened and comprises a semi-circular curved end at its distal end 9.
The cross-sectional view of an embodiment of the invention shown in
If a guidewire 8 is now inserted into the puncture needle 1, it is guided along the inner wall of the adapter 11 directly into the entry opening of the hollow needle 2, which facilitates the insertion of the guidewire 8 into the puncture needle 1 significantly.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2020 105 048.8 | Feb 2020 | DE | national |
This application is a National Stage of International Application No. PCT/EP2021/053808 filed Feb. 17, 2021, which claims benefit of German Patent Application No. 10 2020 105 048.8 filed Feb. 26, 2020, each of which are herein incorporated by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/053808 | 2/17/2021 | WO |
