WO2017029504A1

WO2017029504A1 - Catheter removal device

Info

Publication number: WO2017029504A1
Application number: PCT/GB2016/052555
Authority: WO
Inventors: Saad Munir Bashir RASSAM
Original assignee: Rassam Saad Munir Bashir
Priority date: 2015-08-20
Filing date: 2016-08-18
Publication date: 2017-02-23
Also published as: GB2541443B; GB2541443A; GB201514825D0

Abstract

Apparatus (10) for removing a catheter from the body consists of a forceps-style device with a dissection and engagement structure (30) at its distal end. The structure (30) is a two-part body (36, 38), with a smooth outer surface, tapering towards both distal proximal ends. Opening and closing the two parts (36, 38) provides for blunt dissection of tissue. A hollow channel (44) extends through the centre of the dissection and engagement structure (30) to receive a catheter and there is a sharp edge (46) at the distal end to provide for sharp dissection of tissue.

Description

Catheter Removal Device

The present invention relates to a device for removing an indwelling catheter from a human or animal body.

An indwelling catheter is a central venous line most often used for the

administration of chemotherapy, parenteral feeding or other medications, and for the withdrawal of blood for analysis. Some types are also used for apheresis (blood component separation) or dialysis. These catheters may remain in place in the body for extended periods of time and are used when long-term intravenous access is required.

Such catheters are put in place with the patient under sedation or under general anaesthetic, by a radiologist, anaesthetist or surgeon. Typically they are inserted in the chest but sometimes in the groin or arms. The procedure involves making two incisions. For chest catheters, the first incision is usually in the neck at the jugular vein or other nearby vein such as the subclavian vein. This is the entrance site. A second incision is made on the chest wall, which is the exit site. A tunnel is created under the skin between the entrance and exit sites and the catheter (also commonly referred to simply as a line) is pushed into the body at the entrance site, and through the tunnel, until it exits from the body at the second incision. The portion of line exterior to the entrance site area is then inserted back through the entrance site into the body and advanced into the superior vena cava, preferably near the junction of the vena cava and the right atrium of the heart. The entrance site is then sutured closed. The end of the line exiting the body from the exit site remains external to the body for connection to other systems.

The line can be formed of one, two or three lumens that are integrated into one cylinder within the vein and tunnel, but as the line exits the body, these lumens may separate. Each lumen has a cap and a clamp. At the exit site, the catheter is secured in position in the body by means of a cuff just under the skin. This cuff is a mesh of synthetic fibre material such as Dacron^(RTM) integrated with the exterior of the line. This promotes the formation of fibrous scar tissue that grows into the mesh securing it in place in the body and preventing accidental pulling of the line which might dislodge it. The line external to the exit site is held down against the patient's skin by a sterile gauze or dressing which also serves the purpose of preventing potential contamination at the exit site. The line is usually stitched in place for four weeks allowing the scar tissue to form around the cuff to anchor the line in place.

When the line is no longer required, or becomes a source of infection, it must be removed from the body through the exit site. The cuff securing the line in place is first dissected (i.e. cut free from the surrounding tissue) to allow the line to be pulled out of the body. This dissection should be done in a way to prevent cutting the line partially or completely, which can have serious consequences. Cutting the line will allow air to be drawn into the bloodstream on the right-side of the heart. The heart then pumps the air to the lungs causing an air embolism which can be fatal. A cut line can also cause serious bleeding. In addition, if the cuff is released and then the line completely cut, the catheter can be sucked into the bloodstream causing line embolism. Finally, incomplete dissection of the cuff may cause the cuff to be detached from the line and left behind in the body which can be unsightly and cause tunnel infections.

Removing an indwelling catheter usually involves giving the patient a local anaesthetic, enlarging the exit site by cutting the skin on either side and then bluntly dissecting the cuff with forceps. There is a lack of direct vision and so sharp dissection is not possible. This lack of direct vision cannot guarantee complete cuff dissection. Once the cuff is released along its length and circumference, the line can be pulled out manually. Occasionally, a pull can cause the line to snip partially or completely, particularly if the cuff is not completely dissected out, causing the problems discussed above. The operator will try to remove the cuff entirely through the exit site, but sometimes a second incision must be made higher up the chest at the site of the cuff to allow direct vision and dissection. This adds to the trauma and leaves the patient with another scar and increases the risk of wound infection. The exit site and any further incision will then be sutured closed.

There is therefore a need for an improved means of removing a cuff and indwelling catheter from a patient's body, ensuring safe and complete removal without the need for additional incisions.

The present invention provides apparatus for removing an indwelling catheter from a human or animal body, comprising a forceps with first and second arms having proximal and distal ends and joined by a pivot which allows movement between an open position in which the arms are spaced apart at the proximal and distal ends and a closed position in which the arms are closely adjacent at the proximal and distal ends, further comprising a dissection and engagement member provided at the distal end of each arm, each member comprising an arcuate wall with a smooth outer surface and an inner surface with at least one gripping element, wherein, in the closed position, the members on the first and second arms co-operate to form a hollow dissection and engagement structure with a smooth arcuate outer surface and defining a channel extending therethrough, wherein the outer profile of the dissection and engagement structure alters from a smaller diameter to a larger diameter to a smaller diameter again moving from the distal end to the proximal end to provide for blunt dissection of tissue, and at the distal end of the dissection and engagement structure, the entrance to the channel is provided with a sharp edge to provide for sharp dissection of tissue.

In this way, the present invention provides a single instrument which will allow safer combined sharp and blunt dissection of the cuff and secure pulling of the line with the cuff, without the need for a third incision in the body. As described below, the instrument will use the exit site for its introduction, dissection, engagement of the cuff and pulling of the line, to minimise the risks of the line splitting or snapping and the cuff being left behind. It is simple to use and will allow other medical personnel such as nurses to be trained to use the instrument to remove the lines without the need for complex surgical skills.

In a preferred embodiment, in the closed position, the dissection and engagement structure is a substantially ellipsoid shape.

Preferably, the gripping element comprises at least one rib projecting from the inner surface of each dissection and engagement member. In a preferred embodiment, there are a plurality of longitudinally spaced ribs which are substantially semi-circular. The gripping elements may have sharp edges configured to grip the surface of a cuff to be removed.

Preferably, the channel defined through the body has a diameter larger than the outside diameter of a catheter with which it is intended to be used, and a smaller diameter than the outside diameter of a cuff on the catheter.

Preferably, the apparatus is further provided with a locking means to lock the arms in the closed position. The invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which :-

Figure 1 is a top view of apparatus in accordance with one embodiment of the present invention, in the closed position;

Figure 2 is a top of view of the apparatus of Figure 1 in the open position;

Figure 3 is a perspective view of the apparatus of Figure 1 in the closed position; Figure 4 is a perspective view of the apparatus of Figure 1 in the open position; Figure 5 is an enlarged perspective view of the dissection and engagement structure on one arm of the apparatus.

In accordance with the present invention, the apparatus consists of a forceps 10, which, in a conventional manner, comprise first and second arms 12, 14 configured to cross over one another and joined at the crossover point by a pivot 16. The forceps 10 has a proximal end 18, distal end 20 and a longitudinal axis X.

In the closed position shown in Figure 1 , the arms 12, 14 are closely adjacent to one another at both the proximal and distal ends 18, 20. As shown in Figure 2, in the open position, the arms are pivoted so that at both proximal and distal ends 18, 20, the arms 12, 14 are separated from each other.

Also in a conventional manner, the proximal end 18 of the arms 12, 14 is provided with finger-engaging portions such as loops 22, 24 to receive a user's fingers. A stop may also be provided, typically in the form of projecting tabs 26, 28, which engage against each other in the closed position, to define the fully closed position and provide enhanced stiffness and stability in that position. A locking mechanism (not shown) to lock the arms 12, 14 in the closed position may also be provided. A typical locking mechanism may comprise toothed bars which can be interlocked in different positions to provide closed and graduated open positions.

At the distal end 20, in accordance with the present invention, the forceps 10 is provided with a combined dissection and engagement structure 30. As best seen in Figures 1 and 3, this structure 30 is preferably a generally ellipsoid shape, cut off at each end to provide flat proximal and distal ends 32, 34. As best seen in Figures 2 and 4, the dissection and engagement structure 30 is formed by a pair of half-ellipsoid members 36, 38, secured to or integrally formed with the distal ends of the arms 12, 14. The half-ellipsoid members 36, 38 engage against one another when the forceps 10 is in the closed position to create the ellipsoid structure 30.

The members 36, 38 each comprise an arcuate wall which is smooth on its outer surface. On its inner surface, each is provided with at least one, and preferably a plurality, of gripping elements 40. As shown in Figures 4 and 5, in this embodiment, the gripping elements 40 comprise a series of ribs 42. The ribs 42 are spaced longitudinally from each other, either with equal or unequal spacings. Each rib 42 is substantially semi-circular and each member 36, 38 has a semi-circular opening 48 at its proximal and distal ends 32, 34. Thus, in the closed position, when the two members 36, 38 are brought together to form the ellipsoid structure 30, a clear channel 44 is defined which extends longitudinally through the structure 30. The ribs 42 are substantially triangular in cross-section as shown in Figure 5 to provide a sharp or semi-sharp edge (i.e. not so sharp as to risk cutting or severing parts of the catheter) for gripping the cuff as described below.

The edge 46 of the semi-circular opening 48 at the distal end 34 of each member 36, 38 is sharpened in order to provide a cutting edge for sharp dissection of tissue. The exterior of each member 36, 38 is smooth so that when combined, the ellipsoid structure 30 has a smooth outer profile to assist in blunt dissection of tissue through opening and closing of the device as it is advanced. The edges of the openings 50 at the proximal end 32 of the members 36, 38 may be blunt as no sharp dissection is required at this end. The operation of the forceps 10 to remove an indwelling catheter or line will now be described.

First, a local anaesthetic is applied around the exit site and tissue around the cuff, typically by means of a syringe and needle. Once the anaesthetic has taken effect, a scalpel is used to cut the skin and slightly enlarge the exit site on either side of the line, typically by about 2mm-4mm.

The forceps 10 is engaged over a part of the line external to the body. This may be by threading the line through the channel 44 formed through the ellipsoid structure 30 when the forceps is closed, or by opening the forceps 10, placing the line between the half- ellipsoid members 36, 38 and closing the forceps 10 to enclose a portion of the line within the channel 44. The forceps 10 can slide freely over the line in this condition since the channel 44 through the ellipsoid structure 30 is dimensioned to be slightly larger than the outside diameter of the line.

The operator holding the forceps 10 pushes the dissection and engagement structure 30 into the exit site, sliding it over the line. Gently rotating the forceps 10 helps to advance the structure 30 towards the cuff. Once the distal end 34 of the structure 30 reaches the cuff (this can be felt by the operator through the patient's skin), the forceps 10 is slightly opened to accommodate the larger outside diameter of the cuff. Further rotation of the forceps 10 will cause the cutting edges 46 at the distal end 36 of the structure 30 to start sharp dissection of the scar tissue surrounding the cuff. The forceps 10 may also be gently opened and closed while advancing it in this way and the smooth outer surfaces of the structure 30 will bluntly dissect tissue surrounding the cuff to further loosen it.

These sharp and blunt dissection processes are repeated until the cuff is free and it can be felt through the skin that the distal end 36 of the structure 30 has passed over the inner end of the cuff. The forceps 10 is now fully closed, and preferably locked in the closed position, with the cuff gripped within the channel 44 of the structure 30. As the cuff has a larger outside diameter than the line, the gripping elements 40 engage with and grip the outer surface of the cuff. With the forceps 10 still in the locked closed position, it can be gently withdrawn from the patient, bringing the cuff and line with it without undue pulling force. When fully removed, the exit site can be stitched or secured with adhesive strips and allowed to heal.

Thus, the present invention provides an improved apparatus for removing an indwelling catheter. It provides for both sharp and blunt dissection in a single instrument. The shape of the dissection and engagement structure and the ability to open and close provides blunt dissection, and the leading cutting edge provides sharp dissection. The dissection and engagement structure also provides a means for gripping and pulling the cuff and catheter from the body. Therefore, the catheter cuff can be removed from surrounding tissue more efficiently than using blunt dissection only. Furthermore, the shape of the dissection and engagement structure, with a decreasing diameter towards the proximal end as well as towards the distal end, facilitates smoother non-forceful withdrawal of the device and the catheter from the body in order to minimise patient trauma and risk of catheter snapping.

It will be appreciated that the exact configuration of the dissection and engagement structures may be altered whilst all falling within the scope of the invention as set out in the claims.

For example, the shape of the dissection and engagement members 36, 38 and the combined structure 30 they create may be altered. The outer profile of the structure 30 is preferably smooth and alters from a smaller diameter to a larger diameter to a smaller diameter again moving from the distal end to the proximal end to provide the blunt dissection ability. However, the shape is not necessarily an ellipsoid and other shapes can be envisaged. While the embodiment illustrated shows the dissection and engagement structure 30 to be mounted symmetrically about the longitudinal axis X, the configuration of the forceps arms 12, 14 and the structure 30 itself may be altered so that the structure 30 is offset from the axis X. Similarly, the gripping elements may take a different form, for example, a plurality of teeth or other projections rather than ribs. These may have sharp or semi-sharp edges, or roughened or textured surfaces, for gripping the catheter.

Claims

Claims:-

1 . Apparatus for removing an indwelling catheter from a human or animal body, comprising forceps with first and second arms having proximal and distal ends and joined by a pivot allowing movement between an open position in which the arms are spaced apart at the proximal and distal ends and a closed position in which the arms are adjacent to one another at proximal and distal ends, further comprising a dissection and

engagement member provided at the distal end of each arm, each member comprising an arcuate wall with a smooth outer surface and an inner surface with at least one gripping element thereon, wherein in the closed position, the members co-operate to form a hollow dissection and engagement structure with a smooth outer surface and defining a channel extending therethrough, wherein the outer profile of the dissection and engagement structure alters from a smaller diameter to a larger diameter to a smaller diameter again moving from the distal end to the proximal end to provide for blunt dissection of tissue, and at the distal end of the dissection and engagement structure, the entrance to the channel is provided with a sharp edge to provide for sharp dissection of tissue.

2. Apparatus as claimed in claim 1 , wherein the dissection and engagement structure is a substantially ellipsoid shape.

3. Apparatus as claimed in claim 1 or claim 2, wherein the gripping element comprises at least one rib projecting from an inner surface of each dissection and engagement member.

4. Apparatus as claimed in claim 3, comprising a plurality of longitudinally spaced ribs, each rib being substantially semi-circular.

5. Apparatus as claimed in claim 3 or claim 4, wherein each gripping element is formed with a sharp or semi-sharp edge to grip the surface of a cuff on the line to be removed.

6. Apparatus as claimed in any preceding claim, wherein, in the closed position, the channel is dimensioned to have a diameter larger than the outside diameter of a catheter with which it is intended to be used and a smaller diameter than the outside diameter of a cuff on the catheter.

7. Apparatus as claimed in any preceding claim, further comprising locking means to lock the forceps in the closed position.