Drug elution urine drainage catheter with soft tail end

Abstract

A balloon retaining urinary catheter includes a porous and spongy distal tip. In one method, a polymer is mixed with a sacrificial component, and the mixture is processed to form a tip. When a solvent is applied to the formed terminus, the sacrificial component is eluted from the polymer of the terminus to provide the terminus with a softer porous polymer structure. The tip may be structured to be softer prior to use or to transition to a softer state once in the bladder.

Description

Technical Field

[0001] The following description relates to medical devices. More particularly, the following description relates to catheters, and more particularly to balloon catheters adapted as urinary drainage catheters. Background Art

[0002] Every year, millions of people need a balloon-retained urinary catheter, known as a Foley catheter, for temporary or chronic urinary drainage management. Referring to prior art FIGS. 1 and 2 , a prior art Foley catheter 10 includes a catheter shaft 12 having a first lumen extending to a distal end 14 and leading to a drainage port 16, and a second lumen extending to a retaining balloon 18. The distal end 14 of the catheter shaft 12 has a distal tip 20 that may be integral with the catheter shaft 12 or attached by adhesion or other bonding. The proximal end 13 of the catheter is provided with a hub 24 having a first port 26 and a second port 28 that are adapted to connect the first lumen to a drainage bag and the second lumen to a syringe with an inflation fluid, respectively. The distal tip 20 has a rounded end 22 that is not damaged on the surface. Turning to prior art FIG. 3 , in use, the Foley catheter is advanced along the urethra 30 until the retaining balloon 18 is delivered to the patient's bladder 32. The retention balloon 18 is then inflated with fluid supplied by a syringe through the second lumen until the desired volume of fluid (typically 10 cc to 30 cc) has filled the balloon.

[0003] The distal tip 20 of the catheter serves as the leading end during advancement through the urethra. If the tip is too rigid, it will be difficult to guide the catheter through the bends in the male urethra, and the tip may pierce the wall of the urethra when traversing a sharp bend or an enlarged prostate. On the other hand, if the distal tip 20 is too soft, the catheter may deform and fold back on itself when maneuvering through the area around a swollen prostate, which is common in elderly patients.

[0004] Additionally, once the distal tip enters the bladder, it is detrimental to the patient that the distal tip is as rigid as desired when traveling through the urethra. Referring to prior art FIG. 4 , as the bladder 32 empties, the rigid distal tip 20 contacts the bladder dome 34, thereby "holding up" the bladder dome and creating a single direct contact point that may irritate the bladder tissue. This continued contact has been studied and published in the literature and is known to cause irritation and inflammation, which has been shown to cause bladder and urinary tract infections, which are the leading causes of morbidity and mortality in the hospital setting. Furthermore, if the distal tip punctures the bladder, more serious complications may occur, including sepsis and death.

[0005] Several methods have been studied to counteract such harmful effects, including pancake-shaped balloons with flat tips and double balloon Foley catheters. Pancake-shaped balloons with flat tips are shorter in length and are intended to reduce contact between the catheter tip and the bladder wall once the catheter is in place. The problem with the flat tip design is that it has a shorter length available for travel, and therefore increases the risk of irritation and damage to the sensitive wall of the urethra as the catheter is advanced through the urinary tract into the bladder. The double balloon Foley catheter design uses a first balloon to hold the catheter in the bladder and a second balloon at the distal end to act as a cushion to prevent damage to the bladder wall. The problem with two balloons is that the catheter requires two balloons and two inflation mechanisms, both of which are expensive. In addition, the caregiver must pay attention to two separate inflations, which is cumbersome, must be properly managed, and takes time to operate.

[0006] Another common problem associated with Foley catheters is the numerous instances of infection and encrustation of the catheter. One study estimated that up to 50% of long-term indwelling urinary catheters can become blocked or encrusted, reducing or preventing the drainage of urine through the catheter. As bacteria grow over time, urease is produced, which cleaves uric acid, resulting in ammonium and carbon dioxide. The normal pH range of urine is 4.5 to 8.0; however, the presence of ammonium can increase the alkalinity of urine to a pH as high as 11. As urine becomes alkaline, crystallization of magnesium and calcium phosphates from the urine is initiated. Additionally, bacteria colonize the catheter surface, forming a bacterial biofilm. The crystalline material accumulates in the urine and in the bacterial biofilm and can result in deposits that ultimately block the flow of urine through the catheter.

[0007] A blocked or encrusted catheter can lead to problematic downstream effects. These effects include reflux of urine into the kidneys, sepsis, pyelonephritis, and endotoxic shock. Managing the nucleation pH of urine has been identified as a possible way to inhibit and manage blockage and subsequent bladder stone formation. Blockages have been seen in some studies as early as two days after catheterization. Summary of the invention

[0008] Provided are balloon-retained urinary catheters and components therefor, which solve the various shortcomings of the prior art Foley catheters. In an embodiment, the balloon-retained urinary catheter comprises a catheter shaft having a first lumen extending from a proximal end to a distal end and leading to a drainage port, and a second lumen extending to the retaining balloon. The proximal end of the catheter is provided with a hub having a first port and a second port, the first port and the second port being suitable for respectively coupling the first lumen to a drainage bag and coupling the second lumen to a syringe with an inflation fluid. The distal end of the catheter shaft is provided with a distal tip, which may optionally have a hole positioned in line with the catheter shaft and extending through the distal tip. The distal tip is porous and spongy, and appears soft and non-destructive. The distal tip may be formed integrally with the end of the catheter shaft, or may be formed as a separate cap and, for example, adhered to the distal end of the catheter shaft by a suitable bonding agent. In a preferred manufacturing method, a polymer is mixed or combined or otherwise compounded with a sacrificial component (such as sacrificial particles) that is soluble in a solvent. The combined polymer and sacrificial component are formed into the shape of the distal end. This formation can occur through many mechanical processing steps, including compression molding, injection molding, or spin casting, to obtain the final desired shape. A solvent is applied to the formed distal end. When the solvent is applied to the distal end, the sacrificial component of the distal end dissolves and elutes from the distal end, while the polymer of the distal end is retained due to the insolubility of the polymer in the solvent. Once the sacrificial component is eluted from the distal end, a softer porous polymer structure of the distal end is formed.

[0009] In one embodiment, the solvent may be a liquid phase solvent that is applied to the distal tip when manufacturing the balloon retaining urinary catheter.

[0010] In another embodiment, the solvent can be urine fluid of the bladder applied to the distal end in vivo after the balloon-retaining urinary catheter is placed in the bladder. In this embodiment, the distal end is semi-rigid in the initial structural configuration, which facilitates manipulation through the urethra and into the bladder. Once in the bladder, the distal end automatically changes to a softer, more flexible configuration to prevent irritation of the bladder wall. In order to achieve the changes in hardness and flexibility, a preferred manufacturing method includes making the distal end from a combination of a polymer and a sacrificial component (e.g., a sacrificial particle) that will elute from the distal end in the presence of urine fluid in the bladder. Then, once in the bladder, the sacrificial component is eluted from the polymer, leaving a softer porous polymer structure.

[0011] In another embodiment, a balloon-retained urinary catheter is provided with a distal tip that is similar to the previously described embodiments, but is designed to elute a therapeutic agent (e.g., therapeutic particles) that has a therapeutic effect in the bladder. To have a therapeutic effect, the eluted agent may or may not constitute a drug. Such a distal tip is preferably also adapted to become softer and more flexible as the therapeutic agent (and / or possible other components) elutes from the distal tip of the balloon-retained urinary catheter.

[0012] In another embodiment, a distal end in the form of a cap is provided for attachment to a standard Foley catheter. The cap is preferably 1 to 3 mm thick, and is suitable for covering the distal end of a conventional Foley catheter. The cap may have any structure and therapeutic advantages of the embodiments described above. That is, in one embodiment, the cap may be manufactured to have a soft sponge-like structure, which is suitable for providing an undamaged front end to the standard Foley catheter, thereby preventing stimulation of the bladder wall, and not significantly changing the travel characteristics of the end of the standard Foley catheter. In another embodiment, the cap may be manufactured to be rigid during travel and advancement into the bladder, but then sacrificial components are eluted in the presence of urine fluid to form a softer sponge-like structure that is undamaged to the bladder wall. In yet another embodiment, the cap may be manufactured to be rigid during travel into the bladder, but then one or more component particles are eluted in the presence of urine fluid in the bladder, wherein (one or more) such components may have a therapeutic effect and may also cause the cap to have a softer sponge-like structure that is undamaged to the bladder wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Prior Art FIG. 1 is a balloon-retained urinary catheter of the prior art.

[0014] PRIOR ART FIG. 2 is an enlarged distal end of the prior art balloon-retained urinary catheter of prior art FIG. 1 .

[0015] Prior Art FIG. 3 illustrates a prior art balloon-retained urinary catheter inserted into the bladder when the bladder is full of urinary fluid.

[0016] PRIOR ART FIG. 4 illustrates a prior art balloon retained urinary catheter inserted into a bladder that is sufficiently emptied of urinary fluid such that the bladder dome contacts the distal tip of the prior art balloon retained urinary catheter.

[0017] Figure 5 The distal end of a balloon-retaining urinary catheter according to embodiments herein is shown having a soft tip provided thereto.

[0018] Figure 6 The deformation behavior of a prior art balloon retained urinary catheter subjected to deformation from a 500 g weight is shown.

[0019] Figure 7The deformation behavior of the balloon-retaining urinary catheter described herein is shown subjected to deformation from a 500 g weight prior to immersion in water.

[0020] Figure 8 The deformation behavior of the balloon-retained urinary catheter described herein subjected to deformation from a 500 g weight after being immersed in water for 20 minutes is shown.

[0021] Fig. 9 An embodiment of a balloon-retained urinary catheter is shown inserted into a bladder that is fully emptied of urinary fluid.

[0022] Fig.10 A balloon retaining the distal end of a urinary catheter according to embodiments herein is shown.

[0023] Fig.11 A separate cap is shown for fitting to a conventional balloon retaining urinary catheter. DETAILED DESCRIPTION

[0024] With reference to the following description, the terms "proximal" and "distal" are defined with respect to a hand of a user of the device, with the term "proximal" being closer to the user's hand and the term "distal" being farther away from the user's hand, so as to generally be located farther within the patient's body during use, and specifically intended to be located within the bladder.

[0025] refer to Figure 5 , showing the distal end of a balloon-retained urinary catheter according to an embodiment of the present invention. The balloon-retained urinary catheter 110 includes a catheter shaft 112 having a first lumen extending from a proximal end (not shown, but similar to the proximal end 13 in FIG. 1 ) along the catheter shaft to a distal end 114 and leading to a drainage port 116, and a second lumen extending to a retaining balloon 118. As described with respect to a conventional balloon-retained urinary catheter ( FIG. 1 ) of the prior art, the proximal end of the catheter shaft 112 is provided with a hub having a first port and a second port, the first port and the second port being adapted to respectively couple the first lumen to a drainage bag and couple the second lumen to a syringe with an inflation fluid. According to aspects of the embodiments described herein, the distal end 114 of the catheter shaft is provided with a porous sponge-like distal tip 120. The distal tip 120 may be integrally formed with the end of the catheter shaft, or formed as a separate cap and adhered to the distal end of the catheter shaft, for example, by a suitable bonding agent. The distal tip 120 may optionally have a hole (not shown) positioned in line with the catheter shaft and extending through the distal tip.

[0026] The catheter shaft 112, the retaining balloon 116, and the distal tip 120 may be made of any polymer material commonly used in the manufacture of catheters. Exemplary materials include, but are not limited to, silicone rubber, polyurethane, polyolefin, fluorinated polymer, nylon, amorphous nylon, polyester, amorphous polyester, and combinations thereof.

[0027] The porous sponge-like distal end 120 can be softer and non-damaged than the catheter shaft 112. In the compressibility measurement discussed below, the compressibility of the sponge-like distal end is 20% to 50% higher than the compressibility of the same polymer in a non-sponge form. In an embodiment, the distal end 120 is manufactured by combining a polymer and a sacrificial component (preferably in the form of elutable particles), and then removing the sacrificial component to leave holes in the polymer. The polymer can be the same polymer used in the manufacture of the catheter 112 and / or the balloon 118, or a different polymer. The sacrificial component can include particles such as salts, which can be eluted into a solvent. Exemplary sacrificial component particles include, but are not limited to, sodium chloride, potassium chloride, potassium citrate, sodium citrate, sodium bicarbonate, sodium carbonate, carbonic acid, phosphate buffer powder, potassium phosphate, bismuth subsalicylate, acetylsalicylic acid, salicylic acid, citric acid, sugar, protein, carbohydrate, flour, soluble polymer (polyethylene oxide) and the anhydrous form and the combination of the above. The preferred criteria for the sacrificial component is that the particles of the sacrificial component elute from the polymer surrounding when in the solvent and that the particles leave no toxic residue. The particles are loaded in the polymer at between 10% to 95% by weight of particles to polymer. The preferred ratio is 60% to 70% by weight of particles dispersed in the polymer to polymer. The solvent may be water or any other solvent in which the polymer is insoluble.

[0028] In one manufacturing method, when the polymer is in a molten phase, a sacrificial component is combined with a polymer into a heterogeneous mixture. Then, the heterogeneous mixture is formed into a desired shape for the distal end 120. This formation can occur through many mechanical processing steps, including compression molding, injection molding or spin casting, to obtain the final desired shape. In an embodiment, the distal end 120 can be molded directly onto the distal end 114 of the catheter shaft 112, or can be molded as a separate component for later attachment to the catheter shaft. After the distal end is formed, the distal end can be placed in a suitable solvent (in which the sacrificial component is soluble and the polymer is insoluble). The distal end 120 can remain in the solvent until at least some and preferably substantially all of the sacrificial components have been eluted into the solvent. Preferably, at least 50% of the sacrificial components and up to 100% of the sacrificial components are eluted into the solvent, thereby producing holes in the remaining polymer of the distal end from which the sacrificial components have been eluted.

[0029] In an exemplary embodiment, the sacrificial component may include a combination of equal parts of sodium bicarbonate and anhydrous citric acid in a heterogeneous mixture with a silicone polymer. In the heterogeneous mixture, the sacrificial component may be 70% by weight and the silicone polymer may be 30% by weight. The mixture may be formed into the desired shape of the distal tip. When the resulting distal tip is placed in an aqueous solution (a solvent for sodium bicarbonate and anhydrous citric acid), bubbling occurs as the sacrificial component is eluted into the aqueous solution, which incidentally serves as an indicator of when the elution is complete (i.e., when the bubbling stops). After the bubbling stops, the distal tip is essentially all silicone, with a porous sponge-like structure.

[0030] Other suitable methods may also be used to mix, combine, or otherwise compound the polymer and sacrificial component and form the soft porous polymer structure of the distal tip as described herein.

[0031] In one exemplary embodiment, the distal tip is preferably 1 to 3 mm thick at the most distal end and may act as a pad against tissue.The distal tip may be keyed or otherwise attached to the distal end of the balloon retaining urinary catheter.

[0032] Now go to Figures 6 to 8 , showing a comparison of the sponginess of the distal tip materials described herein relative to conventional materials. Figure 6 The compressibility of a piece of silicone rubber material 50 used to make the distal end of a conventional balloon retaining urinary catheter when subjected to deformation by a 500 g weight 60 is shown. Figure 7 shows the deformation behavior of the porous material 150 described herein for the distal tip of a balloon retaining urinary catheter when subjected to deformation from a 500 g weight 60 prior to immersion in water; and Figure 8 The deformation behavior of the same porous material 150a after being immersed in water for 20 minutes is shown. It can be seen that the distal tip made from the material described herein is significantly more compressible (approximately 25%), especially after being exposed to the fluid in the bladder. Fig. 9 , the resulting porous structure of the distal tip 120 is compressible, has reduced stiffness, and is atraumatic to the inner wall 34 of the bladder 32. As such, the balloon-retaining urinary catheter has a soft and atraumatic distal end without the disadvantages of a pie-shaped balloon or a second balloon.

[0033] refer to Fig.10In another embodiment, a balloon-retained urinary catheter 210 substantially as described above is provided with a distal end 220 that changes structural properties after it is fully manufactured and once it is received in the bladder. The distal end 220 formed is semi-rigid in the initial structural configuration, which facilitates manipulation of the distal end of the catheter through the urethra and into the bladder. The end can be molded and cured in the same manner as the previous embodiment; however, the elution particles are retained in the end until after delivery to the bladder. The elution particles can be any particles that can and safely elute in urine. Therefore, the particles can be many of the same particles described above. In addition, the particles can be those particles that can act as a buffer in urine to maintain the pH of urine within a desired pH range of 6 to 8. As such, the elution particles can provide a therapeutic effect. For example, sodium phosphate and sodium chloride can both be used as elution particles from the distal end.

[0034] When eluted into water or urine, such particles form a phosphate buffered saline. Phosphate buffer systems can be made with dihydrogen phosphate ions (H2PO4 – ) and H + The phosphate buffer is made of balanced phosphoric acid (H3PO4). The pH of the phosphate buffer is 6.8, which allows the buffer to function within its optimal buffering range at physiological pH. As another example, potassium chloride and potassium phosphate can be used in combination as elution particles. As the particles are eluted from the end, the particles can bring the pH of the urine to the preferred range of pH 6 to 8 and prevent the crystallization and crusting of minerals. In addition, the elution particles can include selected proteins, such as histidine.

[0035] In an exemplary embodiment, potassium citrate is mixed into silicone at a weight ratio of 70% potassium citrate to 30% silicone. Once the particles are dispersed in the polymer, the mixture is provided into a mold to form the shaft of the catheter tip and allowed to cure. The cured tip is then bonded to the silicone catheter using an adhesive and allowed to dry. The adhesive may be a room temperature vulcanized silicone adhesive.

[0036] The distal tip 220 is formed to be sufficiently rigid to provide suitable travel through the urethra to the bladder, wherein the potassium citrate precipitates, increases the pH of the urine in the bladder and reduces crusting. The tip becomes soft and non-irritating to the bladder wall, thereby reducing urinary tract infections.

[0037] In another embodiment, a balloon-retained urinary catheter is provided with a distal tip that is similar to the previously described embodiments, but is further designed to elute particles in the bladder that have a therapeutic effect in the bladder. It is appreciated that the eluted particles may or may not be construed as a drug in order to have a therapeutic effect. Such a distal tip is preferably also adapted to become softer and more flexible as particles are eluted from the distal tip of the balloon-retained urinary catheter.

[0038] For example, the effective particles for treatment include potassium citrate, which can increase the pH of urine if the pH of urine is too low. As another example, the effective particles for treatment include citric acid, which can reduce the pH of urine if the pH is too high. This loading can be in the surface of the catheter body 11 or only in the distal end 13 or a combination thereof. The microparticles are loaded into the surface of the catheter body by rolling the catheter (silicone in this example) in a non-cured silicone medium (such as silicone caulking compound), and then the microparticles are pressed into the medium now located on the catheter body and then solidified. When the catheter resides in the bladder, the soluble agent is eluted from the polymer, resulting in the regulation of pH and reducing the rigidity of the distal end material. Other effective particles for treatment may also include antibiotics, antifibrotic agents, antimicrobial agents, anti-inflammatory agents and spasmolytics (anticholinergics), used alone, in combination with each other or in combination with any previously described soluble agents. Exemplary soluble antibiotics include, but are not limited to, amoxicillin, ampicillin, ceftriaxone (Rocephin), cephalexin (Keflex), ciprofloxacin, doxycycline, fosfomycin (Monurol), levofloxacin (Levaquin), methenamine (Hiprex), nitrofurantoin (Macrobid, Macrodantin), trimethoprim / sulfamethoxazole (Bactrim), and similar agents. Exemplary antifibrotic agents include, but are not limited to, paclitaxel, mitomycin C, rapamycin, and analogs of these and similar drugs. Exemplary antimicrobial agents include, but are not limited to, micro-dynamic metals such as copper ions, zinc ions, silver ions, and their associated counterions (chlorides, bromides, iodides, hydroxides, etc.), quaternary ammonium salts, and the like. Exemplary anti-inflammatory agents include, but are not limited to, aspirin and ibuprofen. Exemplary antispasmodic (anticholinergic) agents include oxybutynin.

[0039] Now go to Fig.11In other embodiments, a cap 300 is provided for attachment to a conventional urinary balloon retaining catheter. The cap 300 is manufactured in the same manner as any of the distal tips described above; i.e., in the form of a soft, porous, atraumatic material when manufactured, or with sacrificial particles that cause the tip to become more flexible (spongy) after insertion into the bladder, and / or with therapeutic eluting particles. Thus, the advantages of any of the aforementioned catheters can be applied to a conventional urinary balloon retaining catheter by securing the cap to its distal end. The cap can be secured by a form fit, an interference fit, by gluing or other adhesion, or by any other suitable means.

[0040] Embodiments of balloon-retained urinary catheters, parts thereof, and methods for making such catheters and parts have been described and illustrated herein. Although specific embodiments of the present invention have been described, the present invention is not intended to be limited thereto, as the present invention is intended to be as wide in scope as the art will allow, and the specification should also be read similarly. Therefore, although specific descriptions of using silicone in the construction of the distal end of a balloon-retained urinary catheter have been provided, other polymers suitable for constructing such catheters may be similarly used in the manufacture of soft spongy ends, which may or may not elute therapeutic agents, and are described herein as being suitable in such manufacture. Therefore, those skilled in the art will appreciate that other modifications may be made to the provided invention without departing from the scope of the invention claimed.

Claims

1. A balloon-retaining urinary catheter, comprising: an elongated flexible catheter having a catheter shaft extending between a proximal end and a distal end; a balloon adjacent to the distal end; a drainable port, the drainable port being distal to the balloon; as well as A soft sponge-like polymer distal tip at the distal end, the distal tip being softer than the catheter between the balloon and the distal tip.

2. The balloon-retaining urinary catheter according to claim 1, wherein: The distal tip is attached to the catheter shaft.

3. The balloon-retaining urinary catheter according to claim 1, wherein: The distal tip is porous.

4. The balloon-retaining urinary catheter according to claim 1, wherein: The distal tip is made by the following process: mixing the polymer with the sacrificial component to form a mixture, forming the mixture into a desired shape for the distal tip, and The formed distal tip is placed in a solvent in which the sacrificial component elutes but the polymer is insoluble until at least a portion of the sacrificial component elutes in the solvent and leaves a porous formation in the polymer at the distal tip.

5. The balloon-retaining urinary catheter according to claim 4, wherein: The distal tip is made of at least one polymer selected from the group consisting of silicone, polyurethane, polyolefin, fluorinated polymer, nylon, amorphous nylon, polyester and amorphous polyester; and / or The sacrificial component is made of particles selected from the group consisting of sodium chloride, potassium chloride, potassium citrate, sodium citrate, sodium bicarbonate, sodium carbonate, carbonic acid, phosphate buffer powder, potassium phosphate, bismuth subsalicylate, acetylsalicylic acid, salicylic acid, citric acid, sugars, proteins, carbohydrates, flours, soluble polymers, and anhydrous versions of any of the foregoing.

6. A balloon-retaining urinary catheter for insertion into a patient's bladder, comprising: an elongated flexible catheter having a catheter shaft extending between a proximal end and a distal end; a balloon adjacent to the distal end; a drainable port, the drainable port being distal to the balloon; as well as A distal tip at the distal end, the distal tip comprising a polymer that is insoluble in urine fluid in the bladder and is combined with a sacrificial component adapted to elute in the presence of the urine fluid in the bladder.

7. The balloon-retaining urinary catheter according to claim 6, wherein: The distal tip is adapted to be relatively stiff prior to introduction into the bladder and contact with urine fluid, and to be more flexible after introduction into the bladder and contact with urine fluid.

8. The balloon-retaining urinary catheter according to claim 6, wherein: The distal tip is made by the following process: combining the polymer with the sacrificial component to form a heterogeneous mixture, and The heterogeneous mixture is formed into the shape of the distal tip, and the sacrificial component is non-toxic to the patient when eluted in the bladder.

9. The balloon-retaining urinary catheter according to claim 6, wherein: The polymer is selected from the group consisting of silicone, polyurethane, polyolefin, fluorinated polymer, nylon, amorphous nylon, polyester, amorphous polyester.

10. The balloon-retaining urinary catheter according to claim 6, wherein: The sacrificial component comprises a salt; and / or The sacrificial component comprises at least one of sodium chloride, potassium chloride, potassium citrate, sodium citrate, sodium bicarbonate, sodium carbonate, carbonic acid, phosphate buffer powder, potassium phosphate, bismuth subsalicylate, acetylsalicylic acid, salicylic acid, citric acid, sugar, protein, carbohydrate, flour, soluble polymer and anhydrous forms of any of the foregoing.

11. The balloon-retaining urinary catheter according to claim 6, wherein: The sacrificial component comprises at least one therapeutic agent that is therapeutically effective when eluted into the bladder; and / or The sacrificial component comprises at least one therapeutic agent selected from the group consisting of: an antibiotic, an anti-fibrotic agent, an antimicrobial agent, an anti-inflammatory agent, and an antispasmodic agent; and / or The sacrificial component comprises at least one therapeutic agent selected from the group consisting of amoxicillin, ampicillin, ceftriaxone, cephalexin, ciprofloxacin, doxycycline, fosfomycin, levofloxacin, methenamine, nitrofurantoin, and trimethoprim / sulfamethoxazole; and / or The sacrificial component comprises at least one therapeutic agent selected from the group consisting of paclitaxel, mitomycin C, rapamycin and analogs thereof; and / or The sacrificial component comprises at least one therapeutic agent selected from the group consisting of aspirin and ibuprofen; and / or The sacrificial component comprises oxybutynin; and / or The sacrificial component includes at least one therapeutic agent selected from the group consisting of copper ions, zinc ions, silver ions and their associated counterions, and quaternary ammonium salts.

12. An improved balloon-retaining urinary catheter, the balloon-retaining urinary catheter having an elongated flexible catheter having a catheter shaft extending between a proximal end and a distal end, a balloon adjacent to the distal end, a drainable port distal to the balloon, and a distal tip distal to the drainable port, and having a proximal hub at the proximal end of the catheter shaft, the proximal hub having a first port for communicating with the balloon and a second port for communicating with the drainable port, the improvement comprising: The distal tip is made by the following process: mixing the polymer with the sacrificial component to form a mixture, and forming the mixture into the shape of the distal tip; Therein, the sacrificial component used to form the distal tip is adapted to be eluted in the presence of a solvent, which leaves a porous formation in the remaining polymer at the distal tip.

13. The balloon-retaining urinary catheter according to claim 12, wherein: The sacrificial component is adapted to elute in a solvent including urine fluid, which leaves behind a porous formation in the polymer at the distal tip.

14. An improved balloon-retaining urinary catheter, the balloon-retaining urinary catheter having an elongated flexible catheter having a catheter shaft extending between a proximal end and a distal end, a balloon adjacent to the distal end, a drainable port distal to the balloon, and a distal tip distal to the drainable port, and having a proximal hub at the proximal end of the catheter shaft, the proximal hub having a first port for communicating with the balloon and a second port for communicating with the drainable port, the improvement comprising: The distal tip includes a polymer that is insoluble in urine fluid and is combined with a sacrificial component adapted to elute from the polymer in the presence of the urine fluid.

15. A method for manufacturing a urine drainage catheter, comprising: providing polymers; providing a component material capable of being eluted in a solvent; mixing the polymer with the component materials to form a mixture; as well as The mixture is formed into the shape of a catheter tip that is secured to a catheter shaft.

16. The method according to claim 15, further comprising: A solvent is applied to the catheter tip such that the component materials elute from the polymer in the solvent and leave a porous formation in the remaining polymer at the catheter tip.

17. The method of claim 15, wherein: The component materials are capable of eluting in a solvent including urine fluid.

18. The method according to claim 15, wherein: The catheter shaft includes a balloon.

19. The method according to claim 15, wherein: The polymer includes at least one of the following: silicone, polyurethane, polyolefin, fluorinated polymer, nylon, amorphous nylon, polyester, amorphous polyester.

20. The method according to claim 15, wherein: The component materials are made of particles of at least one of the following: sodium chloride, potassium chloride, potassium citrate, sodium citrate, sodium bicarbonate, sodium carbonate, carbonic acid, phosphate buffer powder, potassium phosphate, bismuth subsalicylate, acetylsalicylic acid, salicylic acid, citric acid, sugar, protein, carbohydrate, flour, soluble polymer and anhydrous forms of any of the foregoing.

21. The method according to claim 15, wherein: The polymer and the component materials are mixed in a ratio of between 20% and 40% of the polymer and between 80% and 60% of the component materials.

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