WO2022021173A1

WO2022021173A1 - Cannula for securing medical tubes

Info

Publication number: WO2022021173A1
Application number: PCT/CN2020/105667
Authority: WO
Inventors: Hao Zhang; Min Hu; Thorsten TIMM; Kirill Koulechov; John VIERO; Xiaowei Zhang; Yuying Fan; Xiaoqi Xu; Hweeyee TEE; Maosong Wu; Peijie XIE; Heqing Huang; Jiaming Dong; Rudolph JAKOB; Nadine KUBAT; Ben KUBLER; Nicki Sutton
Original assignee: Fresenius Medical Care Deutschland Gmbh; Fresenius Medical Care AG & Co. KGaA; Fresenius Medical Care R&D (Shanghai) Co., Ltd.; Fresenius Medical Care Asia Pacific Ltd.; Fresenius Medical Care (Shanghai) Co., Ltd.
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2022-02-03

Abstract

A cannula (1) for cannulation and for securing medical tubes (6), comprising at least one cannula wing (3) for removably affixing the cannula (1) to a patient's body and at least one receiving portion (5) for removably receiving a medical tube (6), wherein the at least one receiving portion (5) is arranged on the at least one cannula wing (3).

Description

CANNULA FOR SECURING MEDICAL TUBES

TECHNICAL FIELD

The present invention relates to a cannula that not only serves the purpose of cannulation but that can also be used for securing medical tubes.

BACKGROUND

In the course of the most medical interventions, cannulation is performed to generate an access to the patient’s body, for example, to withdraw blood samples, withdraw blood for blood purification, as for hemodialysis treatments or administer substances to the patient.

Each cannula typically comprises a needle. The cannula including the needle is attached to a tube. Once the patient is cannulated, the needle has to be secured in place to avoid slipping of the needle from the patient’s body and thus to reduce the risk of contamination and blood loss.

For this purpose, conventionally, the needle and/or the tube are affixed to the patient by the use of tape that holds the cannula wings to the patient’s body. However, conventionally, the medical tubes are loose and thus movement of the tubes can cause the needle to move and ultimately slip from the patient’s body.

If a patient is cannulated multiple times to generate multiple access sites to the patient’s body, the medical tubes associated with the needles can get tangled up. Thus, there is also a need to ensure that medical tubes at cannulation sites are kept in order. Especially in the field of hemodialysis where two puncture sites are necessary and therefore two tubes must be arranged in order.

SUMMARY

Thus, it is the object of the present invention to alleviate or even completely abolish the disadvantages of the prior art. In particular, it is an object of the present invention to provide a cannula for securing the needles at cannulation sites to avoid dislodgement of the needles.

Further, it is an additional object of the invention to provide an easy system for the orderly arrangement of medical tubes, e.g. at cannulation sites.

This object is achieved by a cannula with the features of claim 1. Further advantageous embodiments of the invention are the subject-matter of the dependent claims.

A first aspect of the invention relates to a cannula for cannulation and securing medical tubes, comprising at least one cannula wing for removably affixing the cannula to a patient’s body and at least one receiving portion for removably receiving a medical tube, wherein the at least one receiving portion is arranged on the at least one cannula wing.

Preferably, the at least one receiving portion arranged on the cannula wing is configured to receive a medical tube that is not part of the cannula comprising the receiving portion. This increases the flexibility of the arrangement of the receiving portion on the cannula wing, because design constraints due to for example the need to form a tight loop in the medical tube connected to the cannula bearing the receiving portion and subsequently attach the tube loop to the receiving portion are absent. For example, the receiving portion can be arranged at a distance from a central portion of the cannula where the tube of the cannula that is connected to the needle of the cannula is arranged.

In addition to that, it has proven advantageous if the receiving portion is configured to receive a medical tube in an unbent/uncurved state. In other words, the receiving portion is preferably not configured to receive a tube arranged in a loop shape but is configured to receive a tube arranged in a straight shape. For this purpose, for example, the length of the receiving portion can be such that it runs along the entire width of the cannula wing the receiving portion is arranged at in the longitudinal direction of the needle of the cannula. The provision of such a relatively long receiving portion holds the tube in the receiving portion in a unbent/uncurved state.

In contrast to clips configured to hold the tube in a loop shape, the cannula according to the present invention is simpler and easier to handle, because in principle only one receiving portion needs to be provided. Instead, if the tube is to be held in a loop shape, a clip comprising two receiving portions often arranged in a figure of eight is necessary to hold together both sections of the tube forming the loop. With the cannula according to the present invention, the receiving portion can be directly arranged on the cannula wing without the need for the second receiving portion forming the figure of eight.

Preferably, the at least one receiving portion is fixedly but removably arranged on the at least one cannula wing e.g. by a form-fit mechanism in that the cannula wing comprises an opening into that a corresponding protrusion of the receiving portion is to be inserted.

In an advantageous embodiment, the cannula comprises two cannula wings wherein on each cannula wing a receiving portion for receiving a medical tube is arranged.

The receiving portions can be fixedly but removably arranged at the cannula wings. Alternatively, the receiving portions could be fixedly and inseparably arranged at the cannula wings.

It has been proven advantageous in practice if the at least one receiving portion comprises a receiving groove for inserting a tube and the longitudinal axis of the receiving groove extends essentially at right angles to the longitudinal axis of the cannula wing the receiving portion is affixed to.

Preferably, the inner diameter of the receiving groove is equal or slightly smaller than the outer diameter of the medical tube to be inserted into the receiving portion.

Further, the at least one receiving portion may be configured to partially or completely surround the outer circumference of a medical tube received therein.

It has been proven advantageous in practice if the at least one receiving portion is manufactured to be elastic and/or springy so that a medical tube may be inserted into the receiving groove and held in place by the receiving groove.

For example, the at least one receiving portion may be manufactured from elastic polymer that is deformed upon insertion of the medical tube into the receiving portion, whereby the recoiling forces of the elastic material of the receiving portions hold the medical tube in the receiving portion.

Alternatively, the at least one receiving portion can be manufactured from metal.

The receiving portion (s) can be formed as hooks, loops, clamps or another suitable shape for affixing a medical tube to the cannula.

For example, the at least one receiving portion can take the form of a hook or multiple hooks protruding from the cannula/cannula wing that can be hooked over a medical tube to be secured to the cannula.

Alternatively, the cannula can comprise a hook and loop fastening mechanism in which a loop can be arranged to surround a medical tube and the medical tube is then affixed to the cannula by fixing the loop to a corresponding hook or knob on the cannula.

As a further alternative, the at least one receiving portion can take the form of a locking bracket or bar that is pivotably attached at one end to the cannula/a cannula wing and can be used to clamp a medical tube between the locking bracket or bar and the cannula/cannula wing.

In addition to that, the cannula can also comprise a locking means used to lock the medical tube into place once the medical tube has been inserted into the at least one receiving portion.

Such a locking means can also take the form of a locking bracket or bar that is pivotably attached at one end to the cannula/a cannula wing and can be used to clamp a medical tube between the locking bracket or bar and the at least one receiving portion.

Also, the locking means can be configured to close a receiving portion after a medical tube has been received therein.

For example, in the case of a receiving portion that only partially surrounds the outer circumference of the medical tube received therein, the locking means can close the gap between two opposing ends of the receiving portion to ensure that the entire outer circumference of the medical tube received in the receiving portion is surrounded by the receiving portion and/or the locking means.

If two or more receiving portions are present on the cannula wings, the orientation of the receiving portions/receiving grooves can be all parallel. However, other orientations are possible and the orientation of the receiving portions/receiving grooves can be chosen arbitrarily.

The at least one receiving portion can be formed as single piece. Alternatively, multiple parts can form the receiving portion.

Preferentially, the at least one receiving portion is made from a rigid, flexible or elastic polymer material. The material can comprise an anti-bacterial surface.

Preferentially, the at least one receiving portion is a disposable or a multi-use element.

Further features, advantages and effects of the present invention will become apparent from the subsequent description of an embodiment of the invention shown in the enclosed Figure 1.

Another aspect of the invention relates to a system comprising at least one cannula according to the present invention and at least one medical tube to be received in the at least one receiving portion of the cannula.

Such a system may be part of a cannulation set. Also, a set of receiving portions may be provided to adapt pre-existing cannulae for securing medical tubes.

These receiving portions may have different sizes/dimensions and/or configurations (hooks, loops, receiving grooves etc. ) and may easily be attached to a cannula using a form-fit mechanism.

For example, a cannula can comprise at least one recess/opening, preferably on a cannula wing, and the receiving portions of the set of receiving portions each comprise a protrusion that can be inserted into the recess/opening to affix a given receiving portion to the cannula/cannula wing.

This has the advantage that depending on a specific application, the cannula can be equipped with a specific receiving portion and thus the size and shape of the receiving portion can be customized to an application or patient.

Another aspect of the invention relates to a treatment device, preferably a blood treatment device or infusion device, comprising at least one cannula according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows two cannulae according to the present invention that are used to each secure a medical tube at a cannulation site to thereby prevent the needles from slipping.

DETAILED DESCRIPTION

As can be seen in Fig. 1, each cannula 1 has a needle 2 for accessing the patient’s body.

Each cannula 1 comprises two cannula wings 3 that are affixed to a patient’s arm 4.

Each cannula 1 comprises a receiving portion 5 arranged on a cannula wing 3.

In each receiving portion 5 a tube 6 is received. To each cannula 1 the tube 6 of the other cannula 1 is attached. The tubes 6 are held in an unbent and uncurved state in the receiving portions 5 by a form-fit/friction-fit mechanism. The inner diameter of the receiving grooves of the receiving portions 5 is set to be the same or slightly smaller than the outer diameter of each tube 6. Each receiving portion 5 spans the entire width of the cannula wing 3 it is arranged at. Because there is no need to form a tight loop of a tube, each receiving portion 5 is arranged at a distance from a central portion of the cannula where the tube 6 connected to the needle 2 of the cannula is arranged. In other words, a gap is present between the receiving portion 5 and the central portion of the cannula where the tube 6 connected to the needle 2 of the cannula 1 is arranged.

Preferably, as can be seen in Fig. 1, at each cannula 1 there is a gap between the receiving portion 5 and the central portion of the cannula 1 where the tube 6 connected to the needle 2 of the cannula is arranged and/or the tube 6 connected to the cannula 1. This gap can be present, because the cannula according to the present invention is not configured to hold the tube connected to the cannula in a loop shape, but instead is preferably configured to hold a tube connected to a different cannula in a straight shape.

As shown in Fig. 1, the gap runs along the entire length of the receiving portion 5 between the receiving portion 5 and the central portion of the cannula where the tube 6 connected to the needle 2 of the cannula 1 is arranged. In principle, it would even be possible to arrange the receiving portion 5 at the distal end of the cannula wing 3 from the central portion of the cannula 1.

In this example, the needles 2 are arranged in anterograde and retrograde direction, respectively, i.e. the needles 2 point into opposing directions.

However, this is only one example, and the needles could also both point into the same direction (anterograde or retrograde) . The direction into that the needles can point is arbitrary.

Claims

Cannula for cannulation and securing medical tubes, comprising

- At least one cannula wing for removably affixing the cannula to a patient’s body and

- at least one receiving portion for removably receiving a medical tube, wherein

the at least one receiving portion is arranged on the at least one cannula wing.
Cannula according to claim 1, comprising two cannula wings wherein on each cannula wing a receiving portion for receiving a medical tube is arranged.
Cannula according to one of the preceding claims, wherein the receiving portion (s) is/are fixedly but removably arranged at the cannula wing (s) .
Cannula according to one of the preceding claims, wherein the at least one receiving portion comprises a receiving groove for inserting a tube and the longitudinal axis of the receiving groove extends essentially at right angles to the longitudinal axis of the cannula wing the receiving portion is affixed to.
Cannula according to claim 4, wherein the inner diameter of the receiving groove is configured to be equal or smaller than the outer circumference of a medical tube to be received in the receiving groove.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is formed as single piece.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is made from a polymer material.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is a disposable or a multi-use element.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is configured to hold a medical tube received therein via a form-fit and /or a friction-fit mechanism.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is configured to partially or completely surround the outer circumference of a medical tube received therein.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is configured to receive a medical tube that is not part of the cannula comprising the receiving portion.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is arranged on the cannula wing at a distance from a central portion of the cannula where a tube and /or needle of the cannula is arranged.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is configured to receive a medical tube in an unbent or uncurved state.
Cannula according to one of the preceding claims, wherein the at least one receiving portion is arranged on the cannula wing and extends along the entire width of the cannula wing.
System comprising at least one cannula according to one of claims 1 to 14 and at least one medical tube to be received in the at least one receiving portion of the cannula.
Treatment device, preferably blood treatment device or infusion device, comprising at least one cannula according to one of claims 1 to 14.