WO2015013770A1

WO2015013770A1 - A catheter device

Info

Publication number: WO2015013770A1
Application number: PCT/AU2014/050166
Authority: WO
Inventors: Teresa Kathryn WITHERS
Original assignee: Withers Teresa Kathryn
Priority date: 2013-08-02
Filing date: 2014-08-01
Publication date: 2015-02-05

Abstract

A catheter device including a tubular body with external markings defining at least two zones to indicate a depth of insertion of the catheter.

Description

A CATHETER DEVICE

TECHNICAL FIELD

[0001] The present invention relates generally to medical devices and in particular to a catheter device.

BACKGROUND ART

[0002] The human brain has within it, fluid filled chambers called ventricles. A schematic illustration of the ventricles in the brai is illustrated in Figures 1 and 2, which are an anterior and left lateral view of the brain respectively,

[0003] The fluid which surrounds and cushions the brain and spinal cord is called cerebrospinal fluid or CSF. The ventricles are interconnected and are critical in maintaining the structure of the brain and altering pressure within th brain which is known as the intra- cerebral pressure (ICP). In the event of a change in intra-cerebrai pressure (generally following some type of injury to the brain which could be caused by a knock or infection for example) it may be critical to monitor this change and if necessary, dra off some of the cerebrospinal fluid located in the ventricles in order to decrease the intra-eerebral pressure.

[0004] Intra-ventrieular catheters have been used for more than 20 years to monitor cerebrospinal fluid pressure by connecting them to a pressure transducer. If the pressure is high, it is possible to draw off fluid to decrease the intra-cerebral pressure.

[0005] The catheters used are typical!)' soft but have a firm, metal stylet which runs through the centre of the catheter. The stylet is typically withdrawal once the catheter is in the correct position.

[0006] The process of placement of an intra-ventricular catheter is illustrated in Figures 3 to 6. As illustrated in Figure 3, an incision 10 is typically made in the skin of the patient's head, generally adjacent the swelling of the brain tissue 1 1. A burr hole 12 is drilled into the bone of the patient's skull to create an opening for the catheter as illustrated in Figure 4. The skin of the head is spread using retractors and a catheter is inserted manually through the burr hole 12 as illustrated in Figure 5. The medical practitioner must manually insert the catheter 13 such that the lower end of the catheter 13 sits in a ventricle 14. A. pressure transducer 15 is then attached to the outer end of the catheter to monitor the intracranial pressure as illustrated in Figure 6.

[0007] One problem at present is that placing an intra-ventricular catheter in the correct location can be difficult. When placing the catheter, problems such as altered anatomy, for example the ventricles being smaller than anticipated due to raised intracranial pressure, or displacement of ventricles from the normal anatomical position due to a mass effect for example a haematoma, may occur. When this occurs, operators may be tempted to insert the cathete further, hoping to reach the ventricle, which may already have been passed. The result of this can be injury to delicate brai structures,

[0008] This difficulty is exacerbated by the fact that the size of the catheter is typically very small, normally between 2 mm and 2.7 ram in outside diameter,

[0009] It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publicatio forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

[0010] The present invention is directed to a catheter device, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

[0011 j With the foregoing in view, the present invention in on form, resides broadly in a catheter device including a tubular body with external markings defining at least two zones to indicate a depth of insertion of the catheter,

[0012] The intent of the present invention is to provide a simple, universally understood device allowing an operator to appreciate the depth to which a catheter, particularly an intraventricular catheter has been inserted. Whilst the numbering system may be used, the orientation of the catheter may mean that the numbering system is obscured from view of the operator. This fact coupled with the small size of the catheter meaning that any numbering system used will be printed in very small print, means that using a numbering system to indicate depth of insertion is not an ideal solution to the problem,

[00.13] The catheter device of the present invention can be provided for an type of catheter but is particularly well adapted to use in cerebral intraventricular catheters.

[0014] As mentioned above, the tubular body will have external markings defining at least two zones to indicate a depth of inserti on. Graduations or l i nes or other types of measurements may be provided but where provided, they will be provided in addition to the zones. [0015] Preferably, the zones will be defined over a length of the catheter.

10016] It is particularly preferred that the external markings are easily vi sible from all sides or angles of view of the catheter. For this reason, it is preferred that, the external markings are provided continuously over a particular length of the catheter as well as continuously around the external surface of the catheter over that length..

[0017] It is parti cularly preferred that each zone is provided with an. external marking that is a particular colour. In other words, each zone is preferably a continuous, coloured portion of the external surface of the catheter or applied to the external surface of the catheter.

[0018] It is preferred that particular, and identifiable colours are used and it is most preferred is that a uni ied system of colours such as those used in the "traffic light" convention are used. The use of these particular colours can provide universal recognition in different countries and cultures. Therefore, according to the most preferred embodiment, the particular colours used are green, yellow or amber and red indicatin at least three zones. The remaining portions of the catheter will typically be the base colour of the catheter material which is typically translucent, transparent or opaque with a whitish colour or hue, which is normally the colour of the material used to form the catheter.

[0019] Typically, the zones are adjacent and preferably immediately adjacent one another. There may be a demarcation line or area provided between adjacent zones but typically, the zones will simply be adjacent one another and one zone will terminate where the next zone starts.

[0020) Incremental measurement indicia may be provided in addition to the zones, either within each zone or over the length of the catheter. That is, the measurement indicia may measure the length of the catheter in that zone or more preferably, the length of the catheter from the forward or insertion end to any one or more points over the length of the catheter.

[0021] Each zone is typically a block which is continuous over its length as well as circumferentially around the outer surface of the catheter,

[0022] Generally, a tip portion may be provided which is not a part of the colouring convention. Thi s tip portion will normally be the base colour of the catheter. The length of the tip portion is normally considered in determining the distance to the transition zone. The tip portion is typicall followed by a gree zone of a particular length which is then followed by a yellow or amber zone of a particular length which is then followed in turn by a red zone of a particular length. There is also typically an aft portion further trom the ti after the red zone which is a not a part of the colour convention used for the zones. Normally , the aft portion is not used for anything other than by an operator to i sert the catheter,

[0023] The length of the particular zones may differ for different applications. According to one particularly preferred embodiment, the tip portion (non-coloured) is approximately 3 cm in length, the green zone is approximately 4 cm in length, the yellow or amber zone is

approximately 4 cm in length and red zone is approximately 5 cm in length. This particular configuration is particularly useful as an intraventricular cerebral catheter.

[0024] The number of zones provided on the catheter may vary but three coloured zones are particularly preferred.

[0025] The colours in the zones ma be provided in any way to the catheter. For example, the colours may be provided integral iy with the material used to form the catheter (such as impregnation of a dye or similar) or alternatively, the colour may be provided to an external surface only of the catheter (one method of which is the application of a coloured transfer, coloured ski or coloured adhesive sticker of the appropriate colour or colours to the external surface of the catheter).

[0026] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

[0027] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggesti on that the prior art forms part of the common general knowledge,

BRIEF DESCRIPTION OF DRAWINGS

[0028] Preferred features, embodiments and vari ations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows;

[0029] Figure 1 is an anterior view of the human brain with the location of the ventricles illustrated,

[0030] Figure 2 is a left lateral view of the human brain with the location of the ventricl es illustrated therein.

[0031] Figure 3 is a schematic illustration, showing the first step of introducing an intraventricular catheter namely forming an incision in the skin of a patient's head.

[0032] Figure 4 is a schematic illustration of a second step of forming a hole in the skull using a burr.

[0033 j Figure 5 is a schematic illustration of a third step of manually introducing a catheter through the formed hole.

[0034] Figure 6 is a schematic illustration showing the proper placement of an intraventricular catheter,

[0035] Figure 7 is a schematic illustration of a catheter device according to a preferred embodiment of the present invention.

[0036] Figures 8 A to 8D are illustrations of the respective lengths of catheter inside a human skull and the various zones of the catheter of the preferred embodiment.

[0037] Figures 8E to 8L are illustrations of the insertion of the catheter of the preferred embodiment into a human skull .

DESCRIPTION OF EMBODIMENTS

[0038] According to a particularly preferred embodiment of the present invention, a catheter device 20 is provided.

[0039] According to the preferred embodiment illustrated in Figure 7, the catheter device 20 includes a tubular body with external markings defining five zones to indicate a depth of insertion of the catheter.

[0040] As illustrated, each zone i provided with an external marking that is a particular colour. In other words, each zone is a continuous, coloured porti on of the external surface of the catheter.

[0041 ] The external markings are provided continuousl y over a length of the catheter as well as continuously around the external surface of the catheter over that length. The external markings are therefore easily visibl e from all sides or angles of view of the catheter as well as being viewable from a larger distance than graduations or measurements without coloured zones. The markings can easily be seen by the operator inserting the catheter as well as other observers.

10042 j Particular colours are used and it is most preferred is that a unified system of colours such as those used in the "traffic light" convention are used. Therefore, according to the most preferred embodiment illustrated in Figure 7, the particular colours used are green, yellow or amber and red indicating at least three zones along, the length of the catheter and the location to which the catheter will normally be inserted.

| 0043j The remaining portions of the catheter are^' usually left as the base colour of the catheter material which is typically translucent, transparent or opaque with a whitish colour,

[0044] The zones are adj cent one another and one zone terminates where the next zone starts. As mentioned above, each zone is a block which is continuous over its length as well as circumferential ly around the outer surface of the catheter.

[00453 Generally, a tip portion may be provided which is not a part of the colouring convention , This tip portion will normally be the base colour of the catheter .

[00463 According to the illustrated preferred embodiment therefore, the tip portion 21 is followed by a green zone 22 of a particularly length which is then followed by a yellow or amber zone 23 of a particular length which is then followed in turn by a red zone 24 of a particular length. There is also typically an aft portio 25 further from the tip after the red zone 24 which is not a part of the colour convention used for the zones. Normally the aft portion 25 is not used for anything other than by an operator to insert the catheter,

[00473 The length of the particular zones may differ fo different applications. According to one particularly preferred embodiment, the tip portion (non-coloured) is approximately 3 cm in length, the green zone i s approximately cm in length, the yellow or amber zone is

approximately 4 cm in length and red zone is approximately 5 cm in length. This particular configuration is particularly useful as an. intra-ventricular cerebral catheter,

[00483 The colours in the zones may be provided in any way to the catheter. For example, the colours may be provided integrally with the material used to form the catheter or

alternatively, the colour may be provided to an external surface only of the catheter,

[00493 Use of a colour-coded system which is based on the "traffic light" convention, clear guidance for depth placement can be provided to a catheter. The depth is measured from the dural edge seen within the burr hole. Alternatively, where the catheter is inserted with the use of a guide or locator, the depth can be measured from the outer (or any other suitable) portion of the insertion guide.

[0050] -Simplistic-ally, the white or base coloured zone is the first 3 cm, the green zone is 4 em in length from 3 cm to 7 cm (this is the safe zone and most anteriorly placed intraventricular catheters will enter into the ventricle i this range), the yellow zone is 4 cm in length from 7 cm to 11 cm (this is the caution zone, for parietal catheters insertion to the cautious zone can be acceptable) and the red zone is the subsequent 5 cm in length from 11 cm to 36 cm (the danger zone).

[0051] Thi s is not to say that a catheter cannot be placed i to the red zone depth, only that if doing so, the operator should be acutely aware that the catheter almost certainly will not be in the appropriate location and that there is a high risk of neurological injury at this depth.

[0052] In the event that a catheter moves (such as is inadequately secured) then for example, a catheter original ly placed in the yellow zone wil l clearly have pulled out if the green zone can be seen on the catheter. Therefore, not only can the catheter device of the present invention be used to safely guide insertion of the catheter to the correct depth, but it can also provide easily seen visual indicator of whether a catheter has moved after insertion. This can be a major adjunct to the nursing care of an intra- entricular catheter.

[0053] The length of insertion of the catheter of the preferred embodiment and the position of the tip of the catheter is illustrated in Figures SA to 8D (the catheter is shown outside the skull to show the applicable depth). In Figure 8A, the catheter is illustrated adjacent a full size human skull for reference. Insertion of the catheter into the green zone places the catheter in the location illustrated in Figure 8B. Insertio of the catheter into the yellow or amber zone places the catheter in the location illustrated in Figure 8C. insertion of the catheter into the red zone places the catheter in the location illustrated in Figure 8D

[0054] Figure 8£ shows in detail, the initial insertion of the catheter into the bun^" hole formed in the skull . A more general view of this is illustrated in Figure 8F. Figure 8G shows the catheter placed at the beginning of the green zone which means that the tip is approximately 3cm within the skull . Figure 8H shows the catheter placed approximately two thirds of the green zone into the skull which means that the tip is approximately 5 -6cm within the skull,

[0055] Figure 81 shows the catheter placed at the beginning of the yellow zone which means that the tip is approximately 7cm within the skull. Figure 8 J shows the catheter placed approximately two thirds of the yellow zone into the skull which means that the ti is approximately 9-lOcra within the skull.

[0056] Figures 8 and 81.. show the catheter placed within the red zone which means that approximately 1 1 cm of the catheter is within the skull. At this length, extreme care needs to be taken as a small movement of the catheter can easi iy result in i jury to delicate brain structures.

[0057] Whilst the present invention has been explained with particular reference to an intraventricular catheter, the catheter deviee of the present invention can be applied in any application where successful placement is dependent on depth. This would include but is not limited to intercostal catheters, indwelling urinary .catheters, pig tail catheters, surgical catheters or surgical drainage devices,

[0058 j In the present specification and claims (if any), the word 'comprising' and its derivatives including 'comprises' and 'comprise' include each of the stated integers but does not exclude the inclusion of one or more further integers.

[0059] Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance .of the phrases one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment.

Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

Claims

1. A catheter device including a tubular body with external markings defining at least two zones to indicate a depth of insertion of the catheter.

2. A catheter device as claimed in claim 1 wherein each zone is defined over a length of a portion of the catheter.

3. A catheter device as claimed i claim 1 or claim 2 wherein the external markings are visible from all sides or angles of view of the catheter.

4. A catheter device as claimed in any one of the preceding claims wherein the external

m arkings are provided con tinuously over a particular length of the catheter and continuousl around the external surface of the catheter over that length for each zone.

5. A catheter device as claimed in any one of the preceding claims wherein each zone is

provided with an external marking that is a particular colour.

6. A catheter device as claimed in any one of the preceding claims wherein each zone is a continuous, coloured portion of the external surface of the catheter.

7. A catheter device as claimed in any one of claims 1 to 5 wherei each zone is a continuous, coloured portion applied to the external surface of the catheter.

8. A catheter device as claimed in any one of claims 4 to 7 wherein green, yellow or amber and red are the colours used indicating at least three zones.

9. catheter device as claimed in any one of claims 4 to 7 wherein any remaining portions of the catheter are a base colour of the catheter.

10. A catheter device as claimed in any one of the preceding claims wherein the zones are

immediately adjacent to one another.

1 1. A catheter device as claimed in any one of the preceding claims wherein a demarcation line is provided between adjacent zones.

12 , A catheter device as claimed in any one of the preceding claims wherein incremental

measurement indicia are provided i addition to the zones over a length of the catheter from a forward or insertion end to any one or more points over the length of the catheter.

13. A catheter device as claimed in any one of the preceding claims wherein a tip portion i s provided at a fonvard or insertion end of the catheter which is a base colour of the catheter.

14. A catheter device as claimed in any one of the preceding claims wherein a green zone of a particular length is followed by a yellow or amber zone of a particular length followed by red zone of a particular length are provided from a forward or insertion end of the catheter,

15. A catheter device as claimed in any one of the preceding claims wherein any colour

provided to delineate a zone is applied to an external surface only of the catheter.