Assembly with osmolality-increasing fluid

Abstract

A catheter assembly is disclosed comprising: a hydrophilic catheter; a wetting fluid for wetting of the catheter; and a receptacle enclosing at least the insertable part of the catheter and the wetting fluid. Further, the wetting fluid is a solution incorporating at least one osmolality-increasing compound, and the total concentration of the osmolality-increasing compound(s) is very high, preferably exceeding 600 mOsm / dm3. The wetting fluid could either be arranged in contact with the hydrophilic surface layer of the catheter in the receptacle, for preservation of the hydrophilic surface layer in a wetted state during accommodation in said receptacle and provision of a ready-to-use catheter assembly, or be arranged to keep the wetting fluid separated from the hydrophilic surface layer of the catheter during storage, but to be brought into contact with said hydrophilic surface layer upon activation before an intended use of the catheter. A similar method and wetting fluid is disclosed as well. The provision of the osmolality-increasing compound in the wetting fluid provides several advantages per se, such as a improved properties of the hydrophilic coating, a more predictable and controllable wetting process, a more expedient and cost efficient production, etc. Further, the use of this very high concentration of osmolality-increasing compound in the wetting fluid has proven remarkably efficient.

Description

PRIORITY [0001] This application claims priority from the Swedish patent application SE 0303525-0 by the same applicant, filed Dec. 22, 2003. FIELD OF THE INVENTION [0002] The present invention relates to a catheter assembly of the type comprising a receptacle, a hydrophilic catheter and a wetting fluid. Further, the invention relates to a method for producing such a catheter assembly, as well as a wetting fluid and the use thereof for wetting of a hydrophilic surface layer The invention also relates to a catheter as such. BACKGROUND OF THE INVENTION [0003] Catheters find their use in many different medical applications, such as urinary catheters for bladder drainage. Each catheter is normally pre-packed in a receptacle by the manufacturer, in order to maintain the catheter in a clean and preferably sterile condition. [0004] A urinary catheter in general need to have a lubricant applied to the outer surface thereof to facilitate insertion into the urethra. Especially, for lubricatio...

AI Technical Summary

Benefits of technology

[0014] The wetting fluid may be arranged in wetting contact with the hydrophilic surface layer or coating of the catheter in the receptacle, for preservation of the hydrophilic surface layer in a wetted state during accommodation in said receptacle, whereby a ready-to-use catheter assembly is provided. The assembly may also be such that the wetting fluid is initially kept separated from the hydrophilic surface layer of the catheter during storage of the assembly, and brought into contact with the hydrophilic surface layer upon activation before an intended use of the catheter. This very high concentration of osmolality-increasing compound, exceeding 600 mOsm / dm3, in the wetting fluid has, proven remarkably efficient. Specifically, the high concentration according to the invention is in line with the normal saline concentration in urine (which is about 900 mOsm / dm3) and is much higher than the concentration in a physiological saline solution (about 290 mOsm / dm3). It has surprisingly been found by the present inventors that when a such a high concentration is used for the wetting fluid, the properties of the resulting wetted hydrophilic layer is dramatically improved in respect of e.g. stability during use, stability during wetting, friction and water retention.

[0033] Similar advantages are provided by this aspect of the invention as already discussed in view of the previous aspects of the invention. Specifically, the provision of at least one osmolality-increasing compound in the wetting fluid provides several advantages per se, such as improved properties of the hydrophilic coating, a more predictable and controllable wetting process, a more expedient and cost efficient production, etc. Further, the use of this very high concentration of osmolality-increasing compound in the wetting fluid has, as is already discussed in the foregoing, proven remarkably efficient.

Problems solved by technology

A well-recognized problem with hydrophilic coatings or layers has been that the hydrophilic polymer surface may lose water and dry out when it comes in contact with e.g. a mucous membrane, such as when the catheter is inserted into the urethra.

Naturally, this affects the low-friction properties of the hydrophilic outer surface coating, and may lead to pain and injuries of the patient.

However, these known methods and coatings are affected by some problems.

For example, the production processes, involving different manners of incorporating the osmolality-increasing compounds in the coatings, are rather tedious cumbersome and costly.

Since several such parameters may be unknown beforehand, and may vary to a significant degree, the properties of the resulting, activated coating become unpredictable as well.

However, no information is given about any specific concentration of salt in the wetting fluid.

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