The invention relates to the field of urology, in particular, to a ready-to-use urethral catheter assembly for use in female patients that incorporates means for combining catheterization with introduction into the urethra of lubricating, antiseptic, and anesthetic liquids, individually or in combination, and means for protecting the urethra from introduction of infection during catheterization. The urethral catheter of the invention is convenient for sterile or clean intermittent (short-term) catheterization.
Intermittent catheterization may be necessary for patients who are unable to completely empty the urinary bladder during urination or unable to naturally urinate by themselves temporarily or permanently. Such a condition is known as urinary retention. Intermittent catheterization may also be required, e.g., for obtaining a sterile urinary specimen from a patient in a doctor's office, or for other reasons.
Intermittent catheterization involves the temporary placement of a catheter through the urethra to the bladder for emptying the latter. A goal of intermittent catheterization is to prevent urinary-tract infection by completely emptying the urinary bladder since accumulation of urine in the bladder over a long period of time may create conditions for development of a urinary-tract infection. After a bladder is effectively drained, urinary-tract infections cease to be a problem, and the kidneys are safeguarded.
It is important that prior to insertion of a urinary catheter, the genital area and the meatus, in particular, must be cleaned, preferably with an antiseptic agent, which, however, is not always available to a patient, especially under self-catheterization conditions. Furthermore, it is known that the first third of the female urethra is a harbor of infection, and therefore there is a risk that insertion of the catheter into the urethra and further into the urinary bladder may introduce an infection into the proximal urethra and bladder.
A device that may partially solve the above problem is a urinary plug for use in female patients described in U.S. Pat. No. 5,806,527 issued in 1998 to G. Borodulin, et al. Although the device is not intended for catheterization but rather for preventing involuntary release of urine from the bladder, the device is equipped with an infection-protective cap fitted on the distal end of the plug's tubular body insertable into the urinary bladder through the urethra. First, the infection-protective plug is inserted into the front infectious portion of the urethra, and then the plug is guided through the infection-protective cap without contact with the infectious part of the urethra.
A similar principle of protection against introduction of infection into the urinary bladder is used in a catheter for use in female patients for self-catheterization described in U.S. Pat. No. 6,544,240 issued in 2003 to Borodulin, et al. The device has a sterile infection-protective cap slidingly fitted onto the distal end of said catheter. The cap has a slit on its distal end for possibility of pushing the catheter through the sterile tip into the bladder without physical contact of the catheter with the infectious front part of the urethra.
However, the devices of U.S. Pat. No. 5,806,527 and U.S. Pat. No. 6,544,240 do not have any means that would pre-treat the urethra or facilitate introduction of the plug or catheter into the bladder by treating the urethra during catheterization, e.g., by lubricating the urethral channel, etc.
Urinary catheters supplied for intermittent catheterization in general must have a lubricant applied to the outer surfaces thereof to facilitate insertion into the urethra. For example, hydrophilic urinary catheters have a hydrophilic outer surface coating that should be wetted with fluid such as water or a saline solution for a certain time period before insertion thereof into the urethra of a patient for lubrication purposes.
Various methods for lubricating urinary catheters have been previously proposed, examples of which are given below.
U.S. Pat. No. 5,209,726 makes known a self-lubricating urinary catheter and a method for self-catheterization. The catheter has an annular lubricant reservoir surrounding an inner tube having perforations. As the catheter is inserted into the urethra of a patient, the lubricant is forced from the reservoir into the inner tube and out into the urethra through a discharge outlet in the catheter. Lubrication of the outer surface of the catheter, therefore, only takes place as the catheter is being inserted into the urethra of the patient, resulting in at least some initial discomfort for the patient on insertion of the catheter.
U.S. Pat. No. 3,967,728 makes known a catheter package comprising a urinary catheter and a rupturable, lubricant-containing pouch. One edge of the pouch is located within the package adjacent to the tip of the catheter, and the seal at that edge is constructed so that it ruptures when the pouch is squeezed for lubricating the tip of the catheter. Because only the tip of the catheter is lubricated, the patient still suffers discomfort on insertion of the catheter into the urethra.
U.S. Pat. No. 7.066,912 issued in 2006 to Nestenborg, et al., describes a wetting apparatus for wetting a hydrophilic urinary catheter comprising a wetting-fluid container that holds a wetting fluid and that can be opened by application of a pulling force thereto; a wetting receptacle; and a hydrophilic urinary catheter to be wetted by said wetting fluid and being arranged within said wetting receptacle. The wetting-fluid container is arranged within the wetting receptacle, and the wetting receptacle is extendable for opening the wetting container without rupturing the sealed condition of the wetting receptacle.
Another example of a catheter suitable for self-catheterization is a compact urinary prepacked catheter developed by Coloplast Company (Denmark) and known under trademark SpeediCath™ that can be obtained in a sterile and ready-to-use prehydrated form right out of the package. Each SpeediCath™ comes prepacked in sterile saline solution and in a container that can be taken anywhere, for example, similar to a ballpoint pen. Since SpeediCath™ is prelubricated, its coating is always optimally hydrated to be slippery and therefore comfortable.
Although the SpeediCath™ catheter described above provides a catheter in a ready-to-use form and in a sterile state, it does not guarantee prevention of infection that can be introduced into the urethra during insertion unless the urethral meatus has been thoroughly cleaned before catheterization. Unfortunately, means for cleaning the meatus are not always readily available under conditions where self-catheterization is performed.
However, neither the SpeediCath™ catheter nor any other catheter mentioned above or known to the applicants possesses self-contained and readily available means that simultaneously combine features such as protection against introduction of infection and provision for cleaning the urethral meatus and treating the urethra, e.g., by automatically introducing a lubricant, an anesthetic medium, or an antiseptic substance, or combination thereof, during the process of catheterization.
It is an object of the present invention to provide a catheter assembly for use in female patients that has means for combining catheterization with introduction into the urethra of lubricating, antiseptic, or anesthetic liquids, individually or in combination. It is another object to provide the aforementioned catheter assembly in a self-contained and ready-to-use form convenient for self-catheterization. A further object is to provide the aforementioned catheter assembly with a sterile anti-infectious cap connected to the liquid-containing tubular body of the catheter assembly. A further object is to provide the sterile anti-infectious cap with a protective cover that is reliably attached to the cap and protects the cap from contamination. Another object is to provide the aforementioned catheter with means for cleaning the entrance into the urethra before catheterization.
The device of the invention is a catheter assembly for use in female patients that comprises essentially a urinary catheter that passes through a hollow tubular body filled with a urethra-treating liquid, e.g., a lubricating liquid, anesthetic liquid, antiseptic liquid, physiological solution, or any combination of the above. The proximal end of the tubular body is closed with the piston of a plunger, while the distal end of the tubular body is closed with an anti-infectious cap that is connected to the tubular body. The piston is temporary and releasably fixed to the end face of the tubular body with the possibility of pushing it into the interior of the tubular body by manual force, and the anti-infectious cap has a slit through which the distal end of the catheter can pass and protrude farther out from the device when the piston is shifted forward inside the tubular body. In order to seal the interior of the tubular body during storage of the catheter assembly before catheter use, the catheter has a portion of an increased diameter on the distal end that in a non-operative position is tightly inserted into the interior of the anti-infectious plug and prevents leakage of the liquid through the plug's slit. The catheter inlet opening that is intended for release of urine from the urinary bladder through the catheter, e.g., to the urine-collecting bag, is formed in the aforementioned increased-diameter portion and is overlapped by the inner walls of the anti-infectious cap. The opposite side of the tubular body is closed by the aforementioned piston. The anti-infectious cap is covered with a protective cover that is threaded onto the external thread of the tubular body to protect the anti-infectious cap from contamination.
In use, first the protective cover is disconnected, the anti-infectious cap is inserted into the front infectious part of the urethra until further movement thereof is impossible, and then the plunger is pushed forward and is moved toward the urethra. As soon as the enlarged-diameter portion on the distal end of the catheter passes into the urethra through the slit of the anti-infectious cap, an annular gap is formed between the inner walls of the anti-infectious cap and the outer surface of the small-diameter portion of the catheter. As a result, movement of the piston in the forward direction pumps the liquid from the interior of the tubular body and farther through the aforementioned annular gap and the anti-infectious cap into the urethra. If the liquid is a lubricant, it will facilitate the insertion of the catheter into the urethra. If the liquid is an antiseptic solution, it will perform antiseptic treatment of the urethra, and if the liquid is an anesthetic solution, it will provide painless insertion of the catheter and subsequent post-catheterization treatment. The liquid may comprise a mixture of two or all three components in appropriate proportions. The catheter is molded from a soft biologically acceptable plastic and is disposable.
A catheter assembly of the invention for use in female patients, which as a whole is designated by reference numeral 20, is shown in
The catheter assembly 20 comprises essentially a urinary catheter 22 that passes through a hollow tubular body 24 filled with a urethra-treating liquid L. This liquid may comprise, e.g., a lubricating medium, anesthetic liquid, antiseptic liquid, physiological solution, or any combination of the above.
The proximal end 24a of the tubular body 24 is closed with a piston 26a of a plunger 26, while the distal end 24b of the tubular body 24 is closed with an anti-infectious cap 28 that is rigidly attached to the distal end of the hollow tubular body 24. The cap 28 has a protruding cylindrical portion 28b with a rounded tip and a flat flanged portion 28c. Reference numeral 24f designates the front end face or bottom portion of the tubular body 24 to which the flanged portion 28c can be attached, e.g., by gluing or by thermal welding.
The piston 26a is temporary and releasably fixed to the proximal end face 24c of the tubular body 24, e.g., by press fit, with the possibility of pushing it into the interior of the tubular body by manual force, and the anti-infectious cap 28 has a slit 28a on the rounded tip of the protruding portion 28b through which the distal end 22a of the catheter 22 can pass and protrude farther out from the device 20 when the piston 26a is shifted forward inside the tubular body 24 in the direction of arrow A in
In order to seal the interior of the tubular body 24 during storage of the catheter assembly 20 before catheter assembly use, the catheter 22 has a small-diameter portion 22b, which corresponds essentially to the major part of its length, and a portion 22e of an increased diameter on its the distal end 22a that in a nonoperative or storage position is tightly inserted into the interior of the anti-infectious plug 28 and prevents leakage of the liquid L through the plug's slit 28a.
The catheter inlet opening 22c that is intended for release of the urine from the urinary bladder (not shown) through the catheter 22, e.g., to a urine-collecting bag (not shown), is formed in the aforementioned increased-diameter portion 22e and in the inoperative condition is overlapped by the inner walls of the anti-infectious plug 28. The opposite side, e.g., the proximal 24a of the tubular body 24 is closed by the aforementioned piston 26a. The anti-infectious plug 28 is covered with a protective cover 30 that is threaded onto the external thread 24d of the tubular body 24 to protect the anti-infectious plug 28 from contamination.
In use, first the protective cover 30 (
Following this, the catheter 22 is shifted forward in the direction of arrow A in
As soon as the enlarged-diameter portion 22e on the distal end of the catheter 22 passes into the urethra U through the slit 28a of the anti-infectious cap 28, an annular gap G (
Since, in general, the device of
As shown in the embodiments of
Reference numerals 125 and 127 designate knurled portions on the surface of the cap 122 and the tubular body 124, respectively, which facilitate untwisting of the cap 122 and holding of the tubular body 124 during pushing of the plunger. When prior to use of the urinary catheter assembly 120 the cap is untwisted from the thread 124d and is disconnected from the tubular body 124, the released compressed sponged pad 128 expands and protrudes out from the interior of the cap 122 in the form shown in
Similar to the modification shown in
Thus, it has been shown that the present invention provides a catheter assembly for use in female patients that has means for combining catheterization with introduction into the urethra of lubricating, antiseptic, anesthetic liquids, individually or in combination. The catheter assembly is in a self-contained and ready-to-use form convenient for assisted or self-catheterization. The catheter assembly is provided with a sterile anti-infectious cap made integrally with the body of the catheter. The sterile anti-infectious cap is provided with a protective cover that is reliably attached to the cap and protects it against contamination. Finally, the catheter assembly of the invention is provided with built-in means for cleaning the entrance into the urethra before catheterization.
Although the invention has been shown and described with reference to specific embodiments, these embodiments should not be construed as limiting the areas of application of the invention and that any changes and modifications are possible provided these changes and modifications do not depart from the scope of the attached patent claims. For example, the catheter assembly of the invention is not used only for self-catheterization but may also be used for catheterization of patients by medical personnel in hospitals or outpatient clinics. The catheter can be used for introduction of any therapeutic liquid into the urethra and into any other duct. The plunger, piston, and catheter can be molded as a single piece. Although the urethral catheter of the invention is described as a catheter for use in female patients, with some minor changes in geometry, this catheter can be used for male patients.