Catheter

Abstract

A catheter structure which includes a disc adapted to be positioned in contact with the urethral meatus. The disc is provided with an aperture within which is positioned a thin-walled, flexible, tubular envelope that is secured to the disc. A semi-rigid catheter tube is associated with and supported by the envelope. As the catheter tube is moved toward and into the urethra, the envelope unrolls progressively to cover the walls of the urethra and thereby prevents direct contact between the catheter tube and the walls of the urethra.

Description

This invention relates to medical or surgical instruments and more specifically to an improved catheter.

Catheters available to the medical profession for examination and treatment purposes generally comprise a rigid or semi-rigid catheter tube. The insertion of the catheter causes pain and discomfort to the patient due to the pressure applied and to the friction and scraping of the tube along the walls of the urethra. In diagnostic and treatment techniques it is vital to determine what specific microorganisms are present in the bladder urine. Since other bacteria and microorganisms are present at the exterior and terminal portions of the urethra, ordinary urine specimens are not representative of the organisms in the bladder urine. The first portions of discharged urine may flush out some of these organisms but can not be relied upon to remove all such organisms and later portions of the discharged urine are not necessarily free of these organisms.

Specimens may be obtained from the bladder by introducing a catheter through the urethra, but the conventional catheter will scrape bacteria and microorganisms from the walls of the urethra into the bladder. Discarding the first portion of the specimen will not assure the removal of these undesired organisms. Further, the catheter may actually introduce into the bladder organisms causing infection where such organisms were not previously present in the bladder.

The principle purpose of the present invention is to provide a catheter structure that is relatively simple in construction which eliminates all sliding contact between the catheter tube and the walls of the urethra.

A further purpose of the invention is to provide a catheter structure which prevents transfer of microorganisms along the walls of the urethra from one location to another location and isolates the microorganisms at their initial sites.

Another object of the invention is to provide a catheter structure which permits the taking of a specimen from any desired location along the walls of the urethra.

A further purpose is to provide a catheter structure that prevents introduction of infection causing organisms into the bladder from where it may ascend to the kidneys and cause harm to the patient.

Other objects and advantages of the invention will become apparent from the description taken in conjunction with the drawings wherein:

FIG. 1 is a longitudinal cross sectional view of one embodiment of the structure according to this invention;

FIG. 2 is a perspective view of the structure shown in FIG. 1; and,

FIG. 3 is a longitudinal cross sectional view of a further embodiment of the structure of this invention.

The structure of the present invention contemplates a catheter tube inseparably associated with a thin-walled, flexible, tubular envelope that becomes unrolled or everted progressively to cover the walls of the urethra as the catheter tube is moved forward and into the urethra. The catheter tube and envelope are so proportioned so as to allow the envelope to cover the walls of the urethra along the entire length of the urethra before the catheter tube enters the bladder. Such construction causes the envelope to exert lateral pressure on the urethra walls and thereby isolate any microorganisms at their sites. By such action, the catheter tube is prevented from directly contacting and scraping the urethra walls to cause pain and from transferring microorganisms from the urethra into the bladder. As the catheter tube is withdrawn from the urethra, the tubular envelope progresively uncovers the urethra walls and becomes inverted and thereby prevents direct contact between the catheter tube and the urethra walls.

As illustrated in FIGS. 1 and 2 the instrument includes a disc or plate 1, circular, oval or other desired shape, adapted to be placed in contact with the body surface surrounding the body-opening such as the area surrounding the urethral meatus. The disc 1 is provided with an integral collar 2 which defines an aperture 3 in the disc within which there is positioned a semirigid catheter tube 4. The forward portion 5 of the catheter tube is inseparably supported within a thin-walled, flexible, tubular envelope 6 which terminates at its rearward end in longitudinal bands or straps 7. The catheter tube is provided with apertures 8 through which bands 7 are threaded. The apertures are located rearwardly of the forward end of the catheter a distance which allows the forward end of the catheter to extend into the bladder. The forward portion of the tubular envelope 6 terminates in a cuff 9 which is brought over the collar 2. The forward ends of the bands 7 are brought over the cuff 9 as at 10 and the ends of the bands are secured to cuff and the cuff secured to the collar as by means of a suitable adhesive or by heat sealing.

In use, the instrument is positioned as that the forward end of the envelope 6 and catheter tube is in alignment with the urinal canal or urethra and the disc 1 contacts the urethra meatus. As pressure is applied to the catheter tube 4 in the direction as indicated by the arrow 11, the forward end of the thin-walled envelope unrolls progressively to cover the walls of the urethra. The forward end of the catheter tube moves through the urethra without direct contact with the walls of the urethra. Pressure may be arrested at any desired position so as to permit obtaining a specimen from the walls of the urethra at any desired area by means of an instrument inserted through the catheter tube. The lengths of the thin-walled envelope 6 and the bands or straps 7 are such as to allow the thin-walled envelope to line the walls of the urethra and the forward end of the catheter to enter the bladder without direct contact with the urethra walls. As the catheter tube is withdrawn, the tubular envelope progressively uncovers the walls of the urethra and is withdrawn into the forward end of the catheter tube. Such action prevents direct contact of the catheter tube and the urethra walls.

The modification illustrated in FIG. 3 includes a circular or oval shaped disc 12 adapted to be placed in contact with the body surface surrounding the body opening such as the area surrounding the urethral meatus. The disc is formed of a pair of mating plates 13 and 14 each provided with a central aperture 15 and 16, respectively, and annular kerfs 17 and 18. A semi-rigid, tubular sleeve 19 is disposed within the apertures 15 and 16, being supported therein by means of a thin-walled, flexible, tubular envelope 20. The ends of the envelope 20 are turned outwardly and positioned within the kerfs 17 and 18. The plates 13 and 14 and the ends of the envelope are sealed within the kerfs as by means of a suitable adhesive or by heat sealing. A catheter tube 21 is inseparably secured to the outer end of the envelope 20, as at 22, by means of a suitable adhesive or by heat sealing.

In use, the instrument is positioned so that the forward end 23 of envelope 20 and sleeve is in registry with the urinal passage and the disc 12 abuts the external genitalia. Pressure is then applied to the catheter tube 21 in the direction as indicated by the arrow 24. The pressure thus applied is transferred to the sleeve 19 through the envelope 20. Such force causes the sleeve to move into the urethra and to unroll progressively the envelope and cover the walls of the urethra. At any desired position, the pressure on the catheter tube may be interrupted so as to permit an instrument to be inserted through the catheter tube for the purpose of obtaining a specimen from the walls of the urethra. The lengths of the sleeve 19 and envelope 20 are such as to allow the thin-walled envelope to cover the walls of the urethra and the forward end of the catheter tube to enter the bladder without direct contact with the urethra walls. As the catheter tube is withdrawn, the tubular envelope transfers the force to the forward end of the sleeve, thereby progressively withdrawing the sleeve from the urethra and progressively uncovering the walls of the urethra.

As is apparent from the structures as shown, the catheter tube is prevented from contacting the urethra walls and scraping bacteria from the walls and/or transferring such bacteria into the bladder. The unrolling of the tubular envelope as the catheter tube is moved inwardly into the urethra progressively covers the walls of the urethra and thereby isolates any microorganisms at their sites. Urine specimens withdrawn from the bladder after complete insertion of the catheter tube are thereby free of contamination of such microorganisms as may be present along the urethra walls. The insertion of the instrument may be arrested at any desired position to permit extraction of a sample from the specific position along the walls of the urethra. Further, pain and discomfort to the patient is reduced to a minimum by eliminating friction of the catheter tube on the walls of the urethra.

The instruments are preferably formed of various plastics such as polyethylene, polypropylene, Teflon, nylon, etc. The discs 1 and 12 may be molded polypropylene or nylon. The thin walled envelopes may be formed of a high slip polyethylene to provide a low coefficient of friction between the envelope and sleeve 19 (FIG. 3) or the catheter tube (FIG. 1). The sleeve and catheter tube may be formed of polyethylene or polypropylene.

Claims

1. A catheter structure comprising, in combination, a. a disc having an aperture therein, said disc being adapted to be placed in contact with the area surrounding the urethral meatus with said aperture in registry with the urethra,

b. a thin-walled, flexible, tubular envelope secured to said disc, the forward end of said envelope being disposed within said aperture, said envelope extending rearwardly of said disc and terminating in a plurality of bands, and

c. a semi-rigid catheter tube associated with said envelope, said catheter tube and said envelope having a common axis, the forward end of said catheter tube being inseparably secured to, disposed within and supported by said envelope rearwardly of said disc, said catheter tube having a plurality of apertures corresponding to the number of said bands through which said bands are threaded, said bands extending forwardly over said catheter tube and the ends of said bands are secured to said disc, said apertures in said catheter tube being spaced from the forward end of said catheter tube a distance sufficient to allow the envelope to cover the walls of the urethra and the forward end of said catheter tube within the envelope to enter the bladder,

whereby upon longitudinal movement of said catheter tube toward and into the urethra causes said envelope to unroll progressively to cover the walls of the urethra and upon longitudinal withdrawal of said catheter tube causes said envelope to uncover progressively the walls of the urethra, said envelope being of sufficient length so as to cover the walls

2. A catheter structure as defined in claim 1 wherein said disc is provided with an internal collar defining said aperture, said envelope terminating in a cuff brought over and secured to said collar and the ends of said

3. A catheter structure comprising, in combination,

a. a disc having an aperture therein, said disc being adapted to be placed in contact with the area surrounding the urethral meatus with said aperture in registry with the urethra,

b. a thin-walled, flexible, tubular envelope secured to said disc, the forward end of said envelope being disposed within said aperture, said envelope extending rearwardly of said disc,

c. a semi-rigid tubular sleeve enclosed within said envelope, said tubular sleeve being coextensive longitudinally with said envelope, and

d. a semi-rigid catheter tube associated with said envelope, said catheter tube and said envelope having a common axis, theh forward end of said catheter tube being inseparably secured to and supported by the rearward end of said envelope,

whereby upon longitudinal movement of said catheter tube toward and into the urethra causes said envelope to unroll progressively to cover the walls of the urethra and upon longitudinal withdrawal of said catheter tube causes said envelope to uncover progressively the walls of the urethra, said envelope being of sufficient length so as to cover the walls

4. A catheter structure as defined in claim 3 wherein said disc consists of a pair of mating plates each having an aperture and an annular kerf surrounding said aperture and the ends of said tubular envelope are secured within said kerfs.