Method of preparing a ready-to-use urinary catheter and a catheter assembly for use in said method

Abstract

A method of preparing a ready-to-use catheter by providing a catheter assembly that has a first compartment that includes a catheter therein. The catheter includes on at least a part of its surface an exterior coating designed to reduce the coefficient of friction after treatment with a liquid swelling medium, and a second compartment containing a liquid swelling medium. The method includes sterilising the catheter assembly, adding the liquid swelling medium to the first compartment for wetting/activating the exterior coating of the catheter, and storing the ready-to-use catheter. By using the method according to the invention, the sterilisation of the catheter is effectuated in a dry-state, ensuring that the known problems with wet-sterilisation are completely eliminated and the need for preparing complicated and expensive liquid swelling mediums are no longer required.

Claims

1. A method of preparing a ready-to-use catheter, said method comprising: in a first step, providing a catheter assembly, comprising: i. a catheter disposed in a first location, said catheter comprising on at least a part of its surface an exterior coating arranged to reduce a coefficient of friction after treatment with a swelling medium, and ii. a swelling medium disposed in a second location, said catheter assembly being wrapped or placed in a gas-impermeable package; in a second step, sterilizing the catheter assembly, in a third step, transferring the swelling medium to the first location under sterile conditions inside sterile boundaries of the catheter assembly to wet and activate the exterior coating, wherein said transferring occurs when the catheter assembly is in one or more production facilities, and in a fourth step, storing the ready-to-use catheter, wherein the first step is executed before the second step, the second step is executed before the third step, and the third step is executed before the fourth step.

2. The method according to claim 1, wherein the sterilizing of the catheter assembly is performed by - or -irradiation.

3. The method according to claim 1, wherein the swelling medium is transferred to the first location immediately after sterilizing of the catheter assembly.

4. The method according to claim 1, wherein the ready-to-use catheter can be stored for a period of at least 36 months.

5. The method according to claim 1, further comprising removing any excess swelling medium and/or air present in the first location after the catheter exterior coating has been wetted/activated.

6. The method of claim 1, comprising forming as an intermediate product, a sterilized catheter assembly comprising a first compartment containing the catheter that has on at least a part of its surface the exterior coating that can provide a reduced coefficient of friction when contacted with the swelling medium, and a second compartment containing the swelling medium, wherein the catheter assembly is sterilized with the first compartment in a dry state prior to contact of the catheter exterior coating with the swelling medium.

7. The method of claim 6, wherein the second compartment of the catheter assembly comprises an outlet for discharging the swelling medium, said outlet being closed by a releasable closure and the outlet is arranged in fluid communication with an opening of the first compartment, when the releasable closure is released.

8. The method of claim 7, wherein the releasable closure is a rupturable closure.

9. The method of claim 8, wherein the rupturable closure is in the form of a membrane or welding, which is ruptured by applying pressure on the second compartment.

10. The method of claim 8, wherein the rupturable membrane is connected with an operating device arranged for rupturing the membrane without opening the catheter package.

11. The method of claim 6, wherein the second compartment is a compressible compartment.

12. The method according to claim 1, further comprising providing a hanger or strap or handle attached to the catheter assembly.

13. The method of claim 1, wherein the exterior coating of the catheter is a hydrophilic coating.

14. The method of claim 1, wherein the swelling medium does not contain any hydrophilic polymers and/or any buffer components.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be explained in greater detail below, describing only exemplary embodiments of the irrigation device with reference to the drawing, in which

(2) FIG. 1 shows a first embodiment of a catheter assembly according to the present invention,

(3) FIG. 2 shows a second embodiment of a catheter assembly according to the present invention,

(4) FIG. 3 shows a third embodiment of a catheter assembly according to the present invention,

(5) FIG. 4 shows a final package of the third embodiment according to the invention, wherein the second compartment has been removed,

(6) FIG. 5 illustrates a fourth embodiment of a catheter assembly according to the present invention, and

(7) FIG. 6 shows a final package of the fourth embodiment according to the invention, wherein the second compartment has been removed.

DETAILED DESCRIPTION OF THE INVENTION

(8) The invention will be described below with the assumption that the exterior coating on the catheter is an intermittent catheter comprising a hydrophilic coating and that the liquid swelling medium is a saline solution. However, this assumption is not to be construed as limiting, and the catheter can just as easily be an indwelling catheter, or a suprapubic catheter, or a similar catheter.

(9) FIG. 1 shows a first embodiment of a catheter assembly 1 according to the present invention. Said catheter assembly 1 consist basically of a first compartment 2 comprising the catheter 3, and a second compartment 4 comprising the liquid swelling medium 5, which in the present situation is a saline solution. Said catheter comprises on at least a part of its surface 6 an exterior hydrophilic coating 7 designed to reduce the coefficient of friction after treatment with the liquid swelling medium.

(10) The second compartment 4 comprises an outlet 8 for discharging the liquid swelling medium into the first compartment, said outlet is closed by a releasable closure 9.

(11) In the embodiment shown said releasable closure 9 is a membrane 18 providing a relatively faint joint, which will be ruptured by applying pressure on the second compartment 4, thereby allowing the liquid swelling medium 5 to be in liquid communication with the interior of the first compartment 2 though an opening 10 in said compartment. However, within the scope of the present invention said closure can be any kind of closure which can be opened to expel the liquid swelling medium into the first compartment without compromising the sterility of the catheter assembly.

(12) The first compartment 2 comprises a cavity 11, which very narrowly encloses the part of the catheter 3 being provided with the hydrophilic coating. This results in a very lean and light product, where a very limited amount of liquid swelling medium is sufficient to ensure an easy and highly effective activation of the entire coating.

(13) In the embodiment shown the first compartment 2 is made of a gas-impermeable material and the second compartment 4 is made of a gas-permeable material. It is preferred that the gas-permeable parts of the catheter assembly i.e. the second compartment 4, is removed and/or sealed off from the first compartment 2 in order to maintain sterility of the ready-to-use catheter during the intended lifetime. This is preferably obtained by applying a seal (not shown) in an upper part 12 of the first compartment 2, i.e. the part that is not containing the catheter.

(14) FIG. 2 shows a second embodiment 1 of the catheter assembly according to the present invention. In said embodiment the catheter assembly 1 in FIG. 1 has been placed in an outer packaging 13. Said packaging 13 is arranged such that the first compartment 2 is part of said packaging, and the second compartment is placed inside the packaging. A gap 14 is provided between the second compartment 4 and the packaging 13.

(15) The second compartment 4 has been made of a gas-permeable material. The packaging 13, which constitutes the sterile boundaries, is in contrast made of a gas-impermeable material in order to prevent that the liquid in the activated coating evaporates during the shelf life time of the catheter. This will not only ensure that the liquid, which is contained in the activated coating, cannot evaporate during the lifetime of the catheter, but also that any gas evaporating from the second compartment 4, before the sterilisation step and before the liquid medium is added to the first compartment, will be directed to the gap 14 allowing said gas to diffuse to the first compartment 2, and into the interior of the first compartment 2. This will advantageously ensure that the humidity obtained thereby in the first compartment 2 provides a very effective ethylene oxide sterilization process. The diffusion of gas from the second compartment to the first compartment will be sufficient to provide the desired humidity in the first compartment in order to ensure a very effective ethylene oxide sterilization process, but still to low to activate the coating.

(16) A section 15 of the packaging 13 consists of a gas diffusible bacteria barrier 16 e.g. made of Tyvek that allows for gas-sterilization.

(17) FIG. 3 shows a third embodiment 1 of the catheter assembly according to the present invention. Said embodiment corresponds basically to the catheter assembly 1 in FIG. 2. i.e., the second compartment 4 is placed inside an upper part of the packaging 13. As for the other embodiments 1,1 the second compartment also comprises a membrane 18 which will be ruptured by applying pressure on the second compartment 4, thereby allowing the liquid swelling medium 5 to be in liquid communication with the interior of the first compartment 2.

(18) The embodiment in FIG. 3 however has the addition that it comprises an intermediate section 17, adapted for easy removal and/or sealing of the first compartment 2.

(19) The catheter assembly 1,1 and 1 can be prepared by any conventional means, and have any form or design. In the embodiments shown the second compartment 4 is placed at the upper end of the catheter assembly, however the second compartment 4 could equally well be placed in the opposite end or be placed on one or more sides of the first compartment 2. The only requirement is that during the sterilisation of the catheter assembly 1,1,1 the catheter 3 is contained in the first compartment 2, whereas the liquid swelling medium is contained in the second compartment 4, and that the two compartments are not in liquid communication with each other.

(20) Since the sterilisation is effectuated in the catheter's dry state, the known problems with wet-sterilisation are completely eliminated and the need for preparing and controlling complicated and expensive liquid swelling mediums are no longer a requirement.

(21) After sterilization of the catheter assembly 1,1,1 the liquid swelling medium 5 can conveniently be added to the first compartment 2 under sterile/aseptic conditions by rupturing the membrane 18, by applying force to the second compartment 4. This will ensure that the hydrophilic coating 7 comes into contact with the liquid swelling medium 5, whereby said coating is activated, i.e. said coating 7 swells to a smooth, slippery film 20 making the catheter 3 safe in use by reducing friction during insertion and withdrawal. Since the activation, i.e. addition of the swelling medium to the catheter is effectuate after the sterilisation is complete, the catheter 3 can be stored without loosing its water retention ability and accordingly without obtaining an unadvantageous increase in the coefficient of friction.

(22) Since no further preparation is required prior to use, all the user has to do it to withdraw the catheter 3 from the first compartment 2. Accordingly the catheter according to the present invention can be used directly by end users in any location, e.g. by tetraplegic patients.

(23) During storage the first compartment 2 or the packaging 13 not only acts as a cover ensuring that the surface 6 of the catheter 3 remains uncontaminated prior to use, but said cover can also functions as a protective sleeve enabling the user to hold the urinary catheter during intermittent catheterisation without it slipping due to the coating and without contaminating the sterilised surface.

(24) Any gas-permeable parts of the catheter assembly according to the invention, must preferably be removed and/or sealed off from the remaining catheter assembly, in order to maintain stability of the catheter during the intended lifetime.

(25) This can e.g. be effectuated at the same time as the second compartment 4 is removed from the catheter assembly 1,1,1. It is preferred that the second compartment 4 is removed by e.g. welding and/or heat-sealing, as said methods are both simple and inexpensive and at the same time will ensure that the first compartment 2 effectively is sealed off.

(26) In FIG. 4 is shown final package 19 according to the invention where the second compartment has been removed. Said package include the activated catheter 3, i.e. the coating 7 has been activated to provide a smooth, slippery film 20.

(27) During the removal of the second compartment a hanger/strap 21 placed in proximity to the first compartment as been provided. Said hanger/strap is intended for supporting handling of the catheter by suspending the packaging 13 on a wall, e.g. of a restroom. The hanger/strap is prepared in an intermediate section 17 of the catheter assembly, i.e. a section that neither contains the first 2 or second compartment 4, nor the gas diffusible bacteria barrier 16.

(28) Removing the second compartment before the catheter package 19 is placed in storage, not only means that the stored catheter package 19 will have a smaller size, but also that the liquid swelling medium present in the first compartment has been used for its intended purpose and is contained in the hydrophilic coating. The weight of the swelling medium in the final catheter package is therefore reduced to only slightly more than the wetting fluid contained in the coating when activated, also eliminating the known problems that dripping from the tip of the catheter is avoided. The lower weight and size result in smaller packages, which makes the production easier and less costly, and also makes the products easier and less expensive to handle and store.

(29) FIG. 5 illustrates a fourth embodiment of the catheter assembly 1 according to the invention. For like part the same reference numbers are used as for the previous embodiments.

(30) In the present embodiment the second compartment 4, is not an extension of the first compartment 2, but is instead placed as a projection, extending perpendicular to the first compartment 2. Said second compartment has in FIG. 6 been removed as described above, by applying a seal (not shown) in a section 12 of the first compartment 2.

(31) In addition to encasing the first and second compartment, the outer packaging 13 further contains within its sterile boundaries, a collection bag 22 arranged for collecting urine during catheterisation.

(32) The collection bag 22 is preferably not in liquid communication with the interior of the first compartment 2 during storage, in order to ensure that liquid swelling medium 5 which is not bound to the exterior coating 7 will flow into the collection bag 22.

(33) The opening between the collection bag 22 and the first compartment 2 is closed by a drainage closure 23. Said drainage closure is a releasable closure, arranged such that a liquid communication path can be established between the first compartment 2 and the collection bag 22 without perturbation of the sterility of the catheter packaging.

(34) An example of a tear open system 24 dedicated for users with low dexterity is shown in FIGS. 5 and 6 where tear marks 25 are placed between to handgrips 26. When the package is forced open by forcing the two handgrips from each other, the tip of the package 27 is used as a none touch to withdraw the catheter 6 from the primary package 13 until the catheters connector 28 is trapped in the first compartment 2 just before the tear marks 25. The part 29 of the first compartment 2, which is connected to the collection bag 22, then functions as a kind of connecting hose between catheter 6 and collecting bag 22 during catheterisation, allowing urine to flow through the catheter into the collection bag thereby providing a very hygienic system, which can be used at any location. After catheterisation the catheter 6 can by dropped back in the collecting back 22 and a knot can be tied on the packaging 13 thereby closing the system, which is now ready to be thrown away.

(35) The ready-to-use catheter according to the invention has a simple and inexpensive design, and can therefore be used equally well for both privately and in medical or hospital facilities where known catheters are too troublesome and complicated to use.

(36) Modifications and combinations of the above principles and designs are foreseen within the scope of the present invention.