CA1176530A - Male urinary collection system and external catheter therefor - Google Patents

Abstract

MALE URINARY COLLECTION SYSTEM
AND EXTERNAL CATHETER THEREFOR
Abstract An external catheter, and the method of making such a catheter, for a male urinary incontinence collection system, such system also including a resilient penile skin protector adapted to be adhesively sealed to both the catheter and wearer. The catheter takes the form of a tubular sheath of thin elastic material having a cylindrical body section, a tapered neck section extending therefrom, and a reduced drainage tube section projecting from the neck section. Within the sheath, and constituting an unitary part thereof, is a tubular inner sleeve of soft elastic material having a distal end portion disposed within the neck section and a proximal end portion merging with the sheath's cylindrical body section. The sleeve tapers distally to define an annular space thereabout, and terminates in a reduced distal opening located at an intermediate point within the neck section. The sheath is produced by a dipping process that includes the preliminary step of stretching a pre-formed tubular member (which ultimately forms the inner sleeve) over a dipping form, followed by successive dipping steps.

Description

Background and Summary In co-pending co-owned Canadian application Serial No~ 402,849 filed May 12, 1982, there is disclosed a male urinary drainage device composed of a thin resilient external catheter in place and for producing an effective seal to prevent urine backup and leakage. The pad is formed of compressible, deformable, water-resistant, and elastic sealant material and includes a ring portion adapted to seal about the penis at or directly behind the glans thereof and a pair of integral strap portions projecting from the ring portion and intended to extend inwardly (proximally) along the penile shaft. The strap portions function primarily to provide catheter retention, whereas the ring portion coacts with the retained catheter and with the penis to serve primarily as a barrier against fluid backup.

The external catheter of the co-pending application is provided with convolutions of graduated size in the neck region between the catheter's cylindrical body portion and - its reduced drainage tube portion. Such convolutions permit axial as well as radial expansion and contraction and thereby absorb tensioning forces that might otherwise occlude the lumen or reduce effectiveness of the seal between the pad and catheter, or pad and penis, or both. In addition, the convolutions increase the internal capacity of the neck region to accommodate sudden discharges of urine, thereby reducing the possibilities of fluid backup, or disengagement of or damage to the drainage device, under such circumstances.

Conditions may nevertheless arise where a surge of fluid may create a back pressure that may weaken the seal ~ - 2 -l ~'f~ 3 ` 1 between the pad and catheter, or between the pad and the penis, - resulting in leakage. Should the neck portion o~ the catheter become enlarged or distorted because of fluid pressure, the }
forces generated by such pressure will tend to urge the inner surfaces of the catheter laterally out of sealing contact with the annular portion of the pad. Furthermore~ apart fxom ~he possibility of lea~age arising because of surges of fluid causing a failure of the adhesi~e seal, there is always the risk that gradual deterioration of that seal will occur 10 because of exposure to urine over an extended period, or tha~
the material of the pad will tend to deteriorate because of continuous exposure to fluid, resulting i~ undesirable back flow and leakage.

U s Patent 2,940,450 discloses a drainage de~ice ln the form of an external catheter connected to a flexible tube leading to a suitable receptacle, the catheter being held in place by drawstrings which may be tied together to produce a secure fit. Inllpatent 3,835,857, elastic adhesive tape is wrapped about the catheter in place o~ drawstrings, and i~ ~ J `
20 patent 3,863,638 a liner is disposed beneath the catheter to reduce leakage and promote patient comfort. Patent 4,187,851 discloses a method of forming such a liner in place by wrapping the penile shaft with a double-faced adhesive strip prior to application of the elastic external catheter.

Those devices that have the ad~antage o~ being easily and guickly applied tend to be less effecti~e in terms of retention and pre~ention of fluid backup, where~s those that are more satisfactory in the latter respects areoften relatively difficult to apply and more likely to cause patient 30 discomfort and urethral constriction. Ease of application and ; removal are particularly important because an incontinent iS3U

patient may have other disabilities that make complicated manipulations di~ficult if not Lmpossible to perform. Othe~ ~ f patents reflecting the state of the art are 3,364,932, 3,721,243, 3,361,857, 3,511,~41, 2,891,546, 4,022,213, 3,~26,227, 3,353,538, 1,423,537, 1,015,905', 3,604,424, 4,239,044, 1,490,793, 3,~59,651, and 3,40~,714.

One a5pect of this invention lies in the recognition of the problem of maintaini~g effective adhesive seals under the conditions described above; a second aspect lies in recognizing that the degradation or ruptl~e of such seals may be prevented by providing the external catheter with an elastic tapered internal sleeve disposed within the neck portion of the outer sheath. In use of the catheter, the sleeve is stretched into sealing engagement with the glans to provide a barrier that tends to prevent liquid from migrating rearwardly or proximally towards the adhesive seals formed between the adhesi~e pad, the cylindrical portion of the catheter, and the penis. Should a surge of urine within the neck portion of the catheter cause back pressure, such 20 pressure only tends to increase the effectiveness of the li~uid barrier formed between the glans and sleeve.
Furthermore, where an annular portion of the sleeve is in direct contact with the adhesive pad, such back pressure increases ra~her than diminishes the ~orce of contact betwee~
the sleeve and adhesive pad and.thereby promotes an even more effecti~e liquid-tight adhesive seal.

In brief, the system includes a resilient skin-protecting adhesive pad of the ty~e disclosed in aforementioned co-pending application, the disclosure of which is incorporated 30 . herein by reference, in combination with an external catheter or sheath having a cylindrical body section, a tapered neck section leading ~herefrom, and a reduced drainage ~ube section. Within the sheath, and forming a permanent part thereof, is a tubular inner sleeve of soft elastic ~aterial having a distal end portion disposed within the neck section and a proximal end portion merging wi~h the sheath's body section. 8ecause the sleeve tapers distally, an:annular space is provided between the distal portion of the sleeve and the inner surface o~ the sheath's neck section. A fluid-resistant seal is formed between the sleeve and ~he glans, and any increase in pressure within the annular space about the sleeve only tends to urge the sleeve into tightér sealing engagement with the glans. When the catheter is worn so that the proximal portion of the sleeve engages the ring portion of the adhesive pad, increases in fluid pressure about the sleeve may also result in enhancement of the adhesive seal between the sleeve and pad. The result is an external catheter which has the advantages of adhesive attachment in terms of patient comfor. and convenience, in contrast to 20 prior devices requiring belts, harnesses, and the like, and which at the same time pro~ides a high degree of security against fluid backup and leakage.

- The catheter is formed in a dipping process that includes the preliminary step of stretching a pre-formed tubular member, ultimately to become the inner sleeve, over a dippi~g form. In its unstretched or untensioned state, the tubular member has a distal end portion that tapers and terminates in a reduced distal opening. After stretching the tubular membex upon the form, the distal end portion of 30 that member is treated to prevent liquid latex ~rom bonding thereto. Thereafter, the form i5 dipped into a latex bath ; 1 and the latex coating is then cured to produce the outer sheath, or.at least that portion of the outer sheath -- surroundLng the inner sleeve. When the catheter is stripped from the form, the sleeve returns to its original untensioned state, thereby creating an annular space betwe,en ~he o~tes distal portio~ of ~he sleeve and the inner surface of the sheath's neck section.

Other features, objects, and advantages of the invention will become apparent ~rom the drawings and 10 Specification.

Drawin~s Figure 1 is a side elevational view, shown partly in section, o~ an external catheter embodying the present ; invention, the sheath of the catheter being depicted in unfolded or unrolled condition.

Figure 2 is a view similar to Figure 1 but showing the sheath in rolled condition as it would appear prior to application.

Figures 3 and 4 illustrate the steps of placing 20 the catheter over a penis upon which an adhesive and protective sealing pad has been fitted.

Fi~ure 5 is an enlarged fragmentary generalized sectional view of a catheter showing the relationshi~ between the outer sleeve and sheath.

Figure 6 is a fragmentary sectional view illustrating the relationship between sheath and slPeve in one enbodi~ent of the oatheter, and Figures 7-11 illustrate the seguence of steps for forming a catheter having such a relationship of elements.

!~ 1 Figure 12 is a fragmentary sectional view depicting a second embodiment, and ~igures 13-17 show the method steps for forming a catheter havLng the relztionship of elements represented by the second embodiment.

Detailed Descriptio~

Ref~rring to the drawings, the numeral 10 ge~erally . . ~
designates an external catheter formed o~ soft, highly elastic, natural or synthetic rubber~ ~atural latex i-~preferred but other elastomers having similar properties may o be used. The cathe~er includes an elongated outer sheath 11 and an inner sleeve 12, the two being integrated or perm~nently joined in the manner hereinafter described.

Referring to Figure 1, the sheath 11 includes an elongated cylindrical section 13, a reduced drainage tube section 14, a~d a tapered neck section 15 disposed thexebetween.
The wall thickness o~ the cylindrical section 13 is substantially less than tnat of the neck and drainage tube sections. For e~ample, the cylindrical section may have a wall thickness within the general range of.006to .OlOinchesand,in general, ; 20 is too thin or limp to retain a cylindrical configuration without support. In contrast, the wall thic~nesses of the draLnage tube and neck sections may be.050 ~ches or mo~e and is generally gre~t enough so that such sections will retain the configurations shown in the absence of distorting forces and will spring back ~nto the illustrated shapes when distorting forces are removed.

At its forward or distal end, nec~ section 15 is provided with a rounded tap~r leading to a reduced opening 16.
The drainage tube section 14 tha~ merges with the tapered 30 nec~ section 15 is provided wi h a plurality of con~olutions .3~

or annular enlargements 17 and18. Two such convolutions of graduated size are depicted, their purpose being t~ permit greater stretc~ability, bending, and twisting of the drainage tube section when the de~ice is in use, and to do so with less chance that kinking or obstruction o~ the lumen might occur.. Also, since the interior of the drainage tu~e section is enlarged at such convolutions, the convolutions increase the fluid capacity of that section and pro~ide a reservoir for accommodating surges of fluid when the d~ice is in use~

The inner slee~e 12 has a distal end portion 12a disposed within the ne~k section of the sheath and a prox~al end portion 12b within the sheath's cylindrical body section.
The relationship is depicted most clearly in the seneralized and enlarged view of Figure 5 where it will be seen that the proximal end portion has about the same cross sectional dimensions as the cylindrical bod~ section and merges smoothly : with that section, while the distal portion 12a tapers forwardly and inwardly, terminating in a reduced distal opening 19. Opening 19 is spaced well behind (i.e., proximal 20 to) opening 16 at the distal end of neck section 15. The setback also results i~ the pro~ision of an annular space 20 between the outer.surface of the sleeve's distal end portion 12a a-nd the inner surface o~ neck section 15. The wall thickness of the sleeve 12 may be varied but, to i~sure conformability, good sealing properties, and wearer comfort, such thickness should approximate that o~ the relatively th~n cylindrical body section 13 of the sheath (i.e.,.003 to .005 inches). Thus, both the cylindrical body section 13 a~d the inner sleeve 12 should ~ppear as thin, limp, highly 30 stretchable membranes, in contrast to the drainage tube and neck sec ïons 14, 15 with their shape-retaining properties.

~7~

1 In Figures 1 and 5 the sheath 11 and inner sleeve 12 are shown as merging smoothly with one another. Although the sheath and sleeve are indeed permanently integrated, and are formed of essentially the same material, they ~e actually formed separately to facilitate production and to achieve the desîred setback of the sleeve wi~hin the neck section of the sheath. Figure 6 illustrates what is believed . to be a preferred construction wherein the sleeve 12 is actually a contLnuation of the cylindrical body section of o the sheath. The neck section 15 is permanently joined to - .
the body section 13 at 22~ Such a construction may be made in accordance with the steps depicted in Figures 7-11.

Figure 7 shows a dipping form 23 having a support sha~t 24 that may be mounted upon any suitable reciprocable mechanism ~not shown) for dipping the form into a suitable bath of liquid latex. Prior to any dipping.operations, an open-ended latex tubular member 2; is stretched upon the cylindrical portion of the form (Figure 8~. Such a fitting and stretching operation may be most readily performed 20 starting with the tubular member 25 in fully rolled condition.
The rolled annulus is then simply slipped upwardly onto the lower end of the f.orm 23, is advanced until ~he reduced openi~g 19 at the member's.lower end.is stretched to recei~e the lower end o~ the cylindrical portion of the ~or~, and the annulus is then unrolled. Except for the provision of opening 19 at its lower end, tubular member 25 is generally similar to a conventional latex condom.

While some stretchi~g of the upper portion of member 25 necessarily occurs as that member is fitted upon form 23, 30 the greater stretching occurs at the lower portio~ of that - me~ber because in its relaxed state such lower portion is : _ g _ provided with a rounded taper leading to opening 19 (Figure 7).
It is the stretched lower portion of the tubular member that will ultimately become the distal portion 12a of the sleeve of the finished catheter (Figure 8). The upper portion, 5Ub j ected to only minimal stretching, is to become the cylindrical section 13 of ~h~ sheath.

The form 23 with the elastic tub~lar member stretched thereon is then subjected to successive dipping steps to produce the neck sec~io~ and drainage tub~ sectiQn lo of the final catheter. FiguLe 9 indicates that the form is first dipped to a level x-x in a solution or suspension of a suitable release agent that will prevent latex solution from adhering to the treated surface. An alcohol suspension of diatomaceous earth marketed under the designatio~ Snow Floss by Johns~Mansville Corporation, New York, New York, has been found particularly effective, but other release agents having similar properties may be used. Thereafter, the form is dipped into an aqueous slurry of calcium nitrate or other suitable activator capable of causing a thickening 20 of the latex layer to be subsequently formed by a dipping process, all as well known in the art, and diatomaceous earth.
It will be obser~ed that the leYel y-y to which the form is dipped into the activator slurry is spaced below the level x-x of the release agent treatment (Figure 10).

After remo~al of the form from the activator slurry, the coating is allowed to air dry for a short interval (1 to 3 minutes), and th form is then lowered slowly into a latex bath to a level z-z spaced above x-x as indicated in Figure 11 ; The form should remain within the bath for an interval within 30 the ra~ge of about 4 to 5 minutes; thereafter, the form is removed, dipped in and out of a coagulant solution of calcium ~ 10 --~ ~ 4 ~ U

1 nitrate in alcohol. One or more additional dippings into the ; latex sol~tio~, followed by exposure to coagulant, may be un~ertaken to develop the desired wall thickness. Thereafter, - the form or mandrel with the dip coating thereon is placed in an oven at approximately 135 F. for 40 minutes to c~re the latex. The form a~d nearly compl~ted catheter retained thereon are i~troduced into a water bath maint2ined at approx~mately 160 F. ~or an interval of 30 min~tes or m~re to leach-impurities therefrom. Followins the leaching step, the catheter is stripped from the form or m~ndrel, treated with talc to prevent the latex from sticking to itseif, and dried. The catheter is completed by cutting away the tip to form the opening at the distal end of the drainage tube section. The end result is a catheter as generally depicted in Figures 1 and 5 but in which the layers are formed or joined in the manner specifically illustrated in Figure 6.

E~fective bonding between the two layeIs of latex may be enhanced by the use of solvents or adhesives applied to the annular zone of the tubular member 25 between lines 20 X-X and y-y. It has been found, however, that an effective bond sufficient to permanently integrate the two layers may be simply achieved by dipping the tubular member into a bath of the coagulant described above following the step of fitting the ~ember 25 upon mandrel 23 (Figure 8) and before the step of dipping the form into the release age~t (Figure 9).
The coagulant coating should be air dried for a short inter~al (approximately one minute) prior to the dipping step of Fig F e 9.

The external catheter of ~igures 1 and 5 may also be ` made in accordance with the method steps depicted in 30 Figures 13-17 to produce a construction ha~ing the particular arrangement of layers shown in Figure 12. In that e~bodiment, 1 the i~ner sleeve 12 is formed from the pre-~ormed tubular member 125 stretched upon the form or mandrel 23, and the ~ylindrical section 13, neck section }5, and drai~age tube section 14 are then formed by a dipping process and are thus integrated with the tubular sleeve. The procedural steps are similar to thsse described in connection with Pigures 7-ll except that the tubular member 125 is relatively short and the ~yli~drical section 13 of the sheath is formed during the dipping process rather than being provided as an extension of the pre-formed tubular member.

Specifically, the open-ended latex tubular member ;' 125, having a tapered lower end with a reduced opening 19 r is stretched over form 23 into the position depicted in Figure 14. The form is dipped into a coa~ulant bath and, following an a~r-drying interval of approximately one minute, is then dipped into a solution or suspension of the release coating material to a level x-x represented in Figure 15~
The form is then dipped into the acti~ator bath of calcium nitrate solution to level y-y (Figure 16) and, after an :20 air-drying period of approximately 2 minutes, is successively dipped into latex and coagulant baths. The latex-dipping steps are essentially the same as previously described except that the form is lowered into the latex and coagulant baths to a level w-w near the upper end of the cylindrical body of tne form or mandrel 23 (Figure 17). The Leaching, stripping, and trimming steps are the same as pre~iously described.

It is to be noted that in both methods ~he tapered portion of the tubular member 25 or 125 is pre-formed and stretched upon the mandrel. In both instances, when the 30 dipping processes are completed and the catheters are stripped from the mandrels, the stretched inner slee~es 12 are free to contract and thereby produce the setback depicted in Figures 1, 5, 6, and 12. Specifical~y, the released distal portions of the sleeves retract axially andpxoximally to produce ~he axial spacing between sleeve opening 19 and sheath openi~g 16, and also retract inwardly to form the annular spacing 20 ~Figure 5~.

The catheter would be rolled prior to use, and would normally be marketed in the rolled condition depicted in Figure 2. It will be observed th t the annular roll 27 is of double thickness, being formed of both the cylindrical body section 13 of the sheath and also a substantial length of slee~e portion 12. The reduced opening 19 at the di~stal end of the slee~e, as well as the material of the sleeve immediately surrounding that opening, are therefore fully exposed at the mouth of the rolled catheter.

I~ use of the external catheter, a patient first applies an adhesive pad 30 to the penis 31 as generally illustrated in :~igure 3. The particular pad shown in the drawings is the pad disclosed in the aforementioned co-pending 20 application; however, it is to be understood that while such a pad is particularly suitable, other types of adhesive pads may be used. The pad might, for example, be a spiral wrapping of adhesive material as disclosed in patent 4,187,851 and in other prior Rrt. The particular pad shown in Figure 3 is preferred because the ring portion 30a disposed behind the corona 32 of glans 33 provides a smooth annular surface for sealing contact with the catheter, thereby preventing fluid backup ana lea~age, while the rearwardly (proxLmally) extending strap portions 3Ob act primarily as retaining 30 elements for adhesively holding the sheath in place, thereby preventing disruption of the fluid-tight seals in the r ~

annular zone. The pad may be formed of any suitable resilient material which is not only deformable but also compressible and at least somewhat elastically recoverable. To obtain these properties, the sealant pad may be prepared from a composition composed principally of an elastomeric material such as synthetic or natural rubber. One such material is described in United States patent 2,570,182, being composed of a blend of nitro rubber and polyvinyl chloride. A material of this kind has been sold under the name "Ensolite"* by Uniroyal, Inc. Its use in a sheet arrangement for a male urinary drainage device is described in United States patent 4,187,851. Another such material is composed principally of polyisobutylene. This material has been used in ostomy rings and blankets, and has been sold under the name I'Crixiline''* by Danal Laboratories, Inc., St. Louis, Missouri.
Other suitable materials can be formulated from gelled mixtures of hydrocolloids such as karaya or carboxymethyl ; cellulose and polyhydroxy alcohols such as glycerin or propy-lene glycol, which preferably includes a few percent of fumed silica. Also, to further improve the desired properties of such compositions for use in the present inven~ion, a minor proportion of polyacrylamide resin can be incorporated, and cross-linked by gamma irradiation. See United States patents 4,115,339 and 4,258,715.
The catheter is unrolled over the penis in the manner shown in Figures 3 and 4. Specifically, the rolled catheter is positioned with the exposed apertured portion of sleeve 12 in contact with glans 33, and the catheter is then .~

*Trade Mark unrolled to allow the sleeve to retract into snug contact with the .glans. The proximal end portion of the sleeve, and the cylindrical body section of the sheath, contact the adhesive pad as illustrated in.Figure 4. The distal end porticn 12a of the slee~e may also be brought into co~tact with adhesive pad 30 depending on how closely the pad is positioned to corona 32.

'.
Since the distal portion 12a of the leeve is undex slight te~sion when the external catheter is properly fitted upon the wearer, most of the surface area of the glans, and the ~reas of the penile shaft and the adhesive pad 30 proxLmal to the glans, are protected by the sleeve against direct liquid contact. Should there be a surge in the disch~rge of urine, an uncontrollable occurrence not infrequently associated with spinal injuries, substantial space is provided within the neck section 15 and the con~oluted portion of the drainage tube section to accommodate that surge. Ballooning of the sheath and the development of back pressure may nevertheless ocicur, as indicated in broken lines in Figure 4.
However, should such back pressure develop, such pressure would ha~e the effect of urging the distal end portion 12a of the sleeve into even tighter contact with glans 33, thereby reducing the possibility of leakage. Furthermore, any such back pressure applied to the sleeve 12 in the ~icinity of ~. .
adhesive p~d 3Q will tend to increase the force of contact between the sleeve and pad nd further reduce the possibili.ty of leakage. The result is that the external ~atheter 10, when used in combination with a suitable adhesive sealing pad, is highly e~fective in avoLding problems of leakage should 30 .sudden surges of fluid, accompanied by the development of back pressure, take place.

~ 1 ~;`J~5~3~
. .

I~ is believed apparent.that the external catheter also operat~s to protect the adhesive seals ~etween pad 30, .
catheter 10, and penis 31 against exposure to liquid under normal conditions of use, thereby resulting in a combination which should be expected to give t~e wearer greater security against leakage for lon~er wearing intervals. ~i~imizing _ deterioration of the pad and its sealing properties, as well as the greater comfort arising from reduced continuous exposure of the glans and shaft to the back fiow of urine, are significant advantages of this construction.

A presently preferred composition for use in prepar- ..
ing the sealant pads 30 comprises a mixture of hydrocolloid, polyhydroxy alcohol, fumed silica, and polyacrylamide. A
.; general formula for this type of composition is set out . below.

General ~ormula ,;- Ingredients Parts by Weight ~ydrocolloid 15-25 Polyhydroxy alcohol 50-70 Fumed si~ica 1-3 Polyacrylamide resin 5-20 In the above formula, the hydrocolloid may be karaya gum or other natural hydrocolloid such as gelatin, pectin, etc., or a synthetic .gum such as carboxymethyl cellulose or hydroxyethyl cellulose, or mixtures thereof. The polyhydroxy alcohol is preferably glycerin, or mixtures of glycerin and propylene gly~ol, but other polyhydroxy alcohols can be used.
~ An example of suitable fumed silicas are the.Cab-O-Sil products of Cabot Corporation, Boston, Massachusetts. The ~a~

1 polyacrylamide resin may be a "Reten" resin of ~ercules, In~orporated, as described in United States pat~nts 4,115,339 and 4,258,271. The cited patents also describe gamma irradia~ion cross-linking of the polyacrylamide resins, which is a desirable procedure in preparing the material for the sealant pads of the present invention. An exa~ple of a _ presently preferred specific formulation i~s as follows:

Spècific Formula Ingredients Weight %
o Karaya powder 1~.00 Sodium c~rboxymethyl cellulose 5.00 Polyac~ylamide (non-ionic) 10.00 Polyvinyl alcohol 5.00 Fumedsilica 2.0~
Glycerin 59.73 Propylene glycol 3.05 Methyparaben 0.09 Propylparaben 0.0~
Butylparaben 0.11 100.00~

In compounding the foregoing in g edients, a mixture - can first be prepared of the li~uid ingredients (glycerin, propylene glycol, and the parabens). Fumed silica is then dispersed in the liquid ~X~ure, and thereafter the other powder ingredients are added (karaya, carboxymethyl cellulose, polyacrylamide, and polyYinyl alcohol). The completed mixture is then molded to form the pads, or formed in~o sheets for use in preparing the pads. Either in pad or sheet ~orm, the 30 material is preferably sub~ected to gamma irradiation, preferably ~rom a Cobalt-60 radiation source. The amount . , ' , .

~ 3 1 of radiation employed should be suf~icient to sterilize the ma~erial, and to achieve cross-linking of the poly- ~.
acrylamide resin. For examplel a radiation level of 2.5 megarads is satisfactory. To increase tackiness, the final product is then coated with a conventional medical-grade .
vinyl arcylic pressure sensitive adhesive.
..
_ While in the foregoi~g, embodiments of the invention have been disclosed in considerable detail, it . will be understood by those skilled in the art that many lo of-these details mæy be varied without departing ~rom the . spirit and scope of the invention.
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Claims (16)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR
PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An external catheter for a male urinary drainage system, comprising a tubular sheath formed of soft elastic material having a thin-walled cylindrical body section, a reduced drainage tube section, and a tapered neck section disposed therebetween; said neck and drainage tube sections having a wall thickness substantially greater than that of said cylindrical body section; said sheath also including a tubular inner sleeve of soft elastic material; said sleeve having a distal end portion disposed within said neck section and a proximal end portion disposed within said cylindrical body section; said distal end portion of said sleeve having an unstretched outside diameter smaller than the inside diameter of said neck section to define an annular space therebetween, and terminating in a reduced distal opening spaced axially from the distal end of said neck section; said proximal end portion of said sleeve merging with said cylindrical body section.

2. The catheter of Claim 1 in which said drainage tube section is provided with a plurality of annular convolutions adjacent the distal end of said neck section.

3. The catheter of Claim 2 in which said convolutions are graduated in increasing size towards said neck section.

4. The catheter of Claim 1 in which said distal end portion of said sleeve is provided with a rounded taper extending from said proximal end portion to said reduced distal opening.

5. The catheter of Claim 1 in which said sleeve has a wall thickness substantially thinner than that of said neck and drainage tube sections.

6. The catheter of Claim 1 in which said cylindrical body section and said sleeve are integrally formed and said neck section is sealingly secured to said cylindrical body section about said sleeve.

7. The catheter of Claim 1 in which said body and neck sections of said sheath are integrally formed and said sleeve has its proximal end portion sealingly secured to the interior of said cylindrical body section.

8. The catheter of Claim 1 in combination with a pad formed of resilient, compressible, deformable, and water-resistant material; said pad being provided with tacky adhesive inner and outer surfaces; said pad being adapted to extend about the penis with said inner surface in adhesive sealing engagement therewith and said outer surface adhesively and sealingly engaging said sheath.

9. The combination of Claim 8 in which said pad includes a ring portion adapted to adhesively engage inner surface portions of said cylindrical body section and said sleeve to form a fluid-tight seal therewith.

10. The combination of Claim 9 in which said pad also includes at least one integral strap portion projecting from said ring portion and dimensioned to extend proximally along a penile shaft for adhesively and sealingly engaging both said shaft and said cylindrical body section.

11. A method of making an external catheter, comprising the steps of stretching a pre-formed open-ended tubular latex member upon a cylindrical mandrel so that said member assumes a diameter larger than its unstretched diameter, then treating an annular end portion of the outer surface of said member to prevent liquid latex from bonding thereto while at the same time leaving an adjacent annular portion of said member untreated; then dipping said mandrel into a latex bath to cover said treated and untreated portions of said member; and then curing said latex and stripping the catheter so formed from said mandrel, whereby, when said catheter is stripped from said mandrel, said treated portion of said pre-formed tubular member retracts from the portion of said catheter formed by said dipping and curing steps and extending thereabout, and returns to an unstretched state.

12. The method of Claim 11 in which said pre-formed tubular latex member has its outer surface exposed to a latex coagulant between said stretching and treating steps.

13. The method of Claim 11 in which said pre-formed open-ended tubular latex member has one end portion provided with a rounded taper leading to a reduced end opening when said member is in unstretched condition.

14. The method of Claim 11 in which a section of said mandrel projects below said tubular member after said member has been stretched upon said mandrel, and in which there is the further step, following said treating step and prior to said dipping step, of coating said section of said mandrel and a lower annular portion of said treated portion of said member with an activator capable of promoting an increase thickness of latex to form thereon during said dipping step.

15. The method of Claim 11 in which said pre-formed tubular member extends a substantial portion of the length of said mandrel; said dipping step including introducing said mandrel into said latex bath to a depth substantially less than the full length of said member.

16. The method of Claim 11 in which said member is substantially shorter than the length of said mandrel;
said dipping step including introducing said mandrel into said latex bath a distance approximating the length of said mandrel and well above the upper limits of said member.