WO2002038213A1 - Improved device for securing spinal or venous catheters - Google Patents

Abstract

A device for securing spinal or venous catheters which comprises a body (1) with an adhesive base (2) for securing to the patient's skin, said body (1) being fitted with a throug inner tube (5-6) for the passage of a catheter (100), which tube has a lower inclined section (5) constituting and anti-constriction entry guide for the catheter, and continues with an axial section (6), an externally threaded head (7) being fitted above body (1), to which head is screwed a hollow cap (11) designed fo rhousing a rubber bushing (9) with a central channel (10) of a gauge proportional to the catheter to be secured, which said rubber bushing is suitable to lock catheter (100) in position when cap (11) is screwed on, said cap (11) having a central hole (14) in the end wall to allow the catheter to exit.

Description

IMPROVED DEVICE FOR SECURING SPINAL OR NENOUS CATHETERS

This invention relates to an improved device for securing catheters which are designed to be inserted into the spinal column (spinal catheters) or into the veins (venous catheters).

Access via a suitable spinal or venous catheter has led to some major breakthroughs in medical treatment.

By positioning a catheter in the spinal column, it is possible to administer local anaesthetics and other drugs for surgical anaesthesia or pain- i killing purposes. If a catheter is inserted in a vein, drugs can be infused continuously for therapeutic purposes. As both approaches, ie. venous and spinal, require the catheter to remain in situ for long periods, sometimes for months, one of the major problems is obviously constituted by the need to secure the catheter firmly to prevent its displacement which, in addition to jeopardising the therapeutic effects, would expose the patient to a high risk of the drug's being delivered to tissues other than those in which the catheter was originally positioned.

International patent application no. PCT/EP00/07283, which has not yet been published, describes a catheter securing device comprising a substantially flattened body with an adhesive base for securing to the patient's skin, which presents a through inner cavity with a variety of cross-sections for the passage of a catheter, the first section constituting the housing for a rubber bushing with a central channel, and the second section, of larger diameter, being internally threaded so that it engages a cap, also with a central channel, designed to compress the rubber bushing so as to lock it against the catheter.

The applicants have found that such a solution, though advantageous, can be improved on. The aim of the invention is to perfect the device disclosed in the said international patent application no. PCT/EP00/07283 by improving the adherence of the rubber cylinder to the catheter and reducing the size of the device, so as to improve the patient's compliance. This aim is achieved by the invention with the characteristics described in the annexed independent claim 1.

Advantageous embodiments of the invention appear in the dependent claims.

Basically, the catheter securing device in accordance with the invention comprises a substantially flattened body with an adhesive base for firm application to the patient's body; the said flattened body has an internal cavity for the passage of a catheter and an externally threaded head with a smaller diameter, to which is screwed a hollow cap destined to house a rubber bushing with a central channel of a gauge proportional to the catheter, which said rubber bushing is suitable to lock the catheter without constricting it when the cap is screwed on.

The body of the device has an anti-constriction catheter entry guide. Further characteristics of the invention will appear more clearly from the detailed description that follows, which relates to a form of embodiment described by way of example but not of limitation and illustrated in the annexed drawings, in which: figure la is a plan view of the body of the catheter securing device in accordance with the invention; figure lb is a view from below of the device shown in figure la; figure lc is a median section through plane I-I shown in figure la; figure 2a is a median section of a cap designed to close the body shown in figures la-c at the top; fιgure 2b is a view from above of the cap shown in figure 2a; figure 3a is an exploded median section of the device in accordance with the invention, which also shows a rubber bushing designed to lock the catheter in position; figure 3b is a median section of the assembled device, complete with catheter.

These figures, and in particular figures la-c, show a body 1, conveniently made of plastic, which presents a substantially flat side 2 and a convex opposite side 3, which is substantially semi-cylindrical, sides 2 and 3 being joined by lateral wings 4 with rounded edges. Flat side 2, which corresponds to the rear side of body 1 , is adhesive, or double-sided adhesive tape is fixed to it to ensure firm anchorage to the patient's skin after the insertion of catheter 100, only shown in figure 3b.

Body 1 has an inner tube which passes from one end to the other, comprising a lower section 5 that enters body 1, shown in the bottom part of the annexed drawings, which is angled at approximately 30 degrees from the vertical and constitutes a guide for catheter 100, preventing it from bending and being pulled out in the passage from the patient's body to the securing device in accordance with the invention.

After angled section 5, the said through tube continues with a straight vertical section 6, which extends to the top end of body 1.

At the top of body 1 there is a cylindrical head 7 with a smaller diameter than the body, at least part of which head has external threading 8 to which is fitted a cap 11, which has internal threading 12 for this purpose.

Cap 11 is internally hollow so as to form a housing 13 for a rubber bushing 9 which has a through central channel 10 aligned with the straight section 6 of the inner tube of body 1 and with hole 14 in the bottom of cap 11 so as to allow the passage of catheter 100 as shown in figure 3b.

At the assembly stage of the device, if cap 11 is suitably screwed to body 1, rubber bushing 9 will be compressed so as to reduce the gauge of its channel 10, possibly with the aid of a washer 16 inserted between the rubber bushing and the head of body 1 to standardise the pressure exerted by cap 1 1, so as to make rubber bushing 9 adhere so tightly to catheter 100 that the said catheter is firmly secured without being constricted (figure 3b).

When catheter 100 exits from hole 14 in cap 11 as shown in figure 3b, it can be connected normally to the classic infusion systems.

As shown in the figures, the diameter of cap 11 does not exceed the thickness of body 1 , so as to make the device fairly compact and thus improve the patient's compliance.

The thread, with relatively wide pitch, allows the cap to be screwed on with a small number of turns.

The skirt of cap 11 presents ^'a plurality of vertical grooves 17 designed to aid gripping and handling. The structure of the device in accordance with the invention produces improved adherence of rubber bushing 9 to catheter 100.

The dimensions shown in the annexed drawings are obviously given merely by way of example; in particular, channel 10 in rubber bushing 9 will be made in various diameters, depending on the gauge of the catheter 100 used.

If the catheter securing device in accordance with the invention needs to be replaced without removing catheter 100 from the site of implantation, it is sufficient to unscrew cap 11 and gently detach adhesive base 2 in order to detach body 1 from the free catheter and insert a new securing device if required.

If catheter 100 is removed, the securing device in accordance with the invention will be directly removed with the catheter.

The details set out above clearly indicate the advantages of the invention, which wholly achieves the desired aims.

The invention is obviously not limited to the particular embodiment described above and illustrated in the annexed drawings; numerous details could be modified without departing from the scope of the invention as defined in the claims set out below.

Claims

1. Device designed for securing spinal or venous catheters, comprising a body 1 with a substantially flat side 2 which can be secured to the patient's skin with adhesive means, which body 1 contains a through inner tube 5-6 for the passage of a catheter 100 and has an upper head 7 with an inner thread 8 to which is screwed a hollow cap 11 designed for housing a rubber bushing 9 which contains a central channel 10 aligned with a central hole 14 in the bottom of cap 11 for the passage of catheter 100, in which said rubber bushing 9 is compressed by screwing cap 11 so as to lock said rubber bushing against catheter 100 without constricting it.

2. Device as claimed in claim 1,- characterised in that said through tube in body 1 constitutes an anti-constriction entry guide for catheter 100, which comprises an inclined lower section 5 and continues with an axial section 6 which is aligned with channel 10 in rubber bushing 9 and hole 14 in cap 11.

3. Device as claimed in claim 2, in which said inclined section 5 has an inclination of approximately 30 degrees from the axis of body 1.

4. Device as claimed in claim 1, characterised in that the diameter of said head 7 of body 1 is smaller than the thickness of body 1, and that the outer diameter of said cap 11 is no greater than the thickness of body 1 , so as to reduce the size of the device.

5. Device as claimed in claim 1, characterised in that said central channel 10 of rubber bushing 9 has a gauge proportional to catheter 100 to be secured.

6. Device as claimed in any one of the preceding claims, characterised in that a washer 16 is inserted between said rubber bushing 9 and said head 7 of body 1 in order to standardise the pressure exerted by cap 1 1 on the rubber bushing.

7. Device as claimed in any one of the preceding claims, characterised in that said thread designed for screwing cap 11 to head 8 of body 1 has a wide pitch.

8. Device as claimed in any one of the preceding claims, characterised in that said cap 1 1 has external grooves 17 designed for making it easier to grip.

9. Device as claimed in claim 1, characterised in that said adhesive means are integral with said base 2 of body 1.