Catheter With Wall Perforations

This invention mimics the body's own defense against infection of the urethra through irrigation of the urethral mucosa with urine. This object is shared by German applications DE 32 02 713 C2, DE 33 06 342 A1, DE 36 34 569.5 and G 86 26 896.1. In the instant invention the wall of the catheter contains one or more openings or windows (9) where it passes through the urethra. The urine passing through the interior of the catheter can flow through these relatively large windows to the surrounding mucosa of the urethra and irrigate them. Compared with the cited applications, the catheter of the instant invention can be constructed relatively simply and inexpensively. While the wall openings of P 33 06 342 primarily serve to lead urine from the area between the urethral wall and the catheter wall back into the lumen of the catheter, in the instant invention the urine circulates from the lumen through the windows outward towards the urethral wall--i.e. in the opposite direction--and back to the lumen. Through this continual irrigation of the numerous urethral areas, bacteria ascending from the orifice of the urethra are rinsed away.

In one variation adjacent windows (9) are staggered in their locations relative to each other, as shown in FIG. 4. In order, if required, to ensure sufficient stiffness of the catheter wall in the region of the windows, the catheter wall material in this region may be made stiffer than in the remaining parts of the catheter, so as to hold the catheter lumen (18) open. A preferred way to keep the catheter from being expelled from the bladder is through the use of a balloon (3), as shown in FIGS. 1-3. The inflation channel (4) for such a balloon (3) is, in the window-equipped region of the catheter, routed within the lumen, so as not to interfere with the windows. In a variation on this embodiment, the inflation channel (4) is integrated into the catheter wall, itself. In an especially preferred embodiment, the urine is routed between the outside surface of the catheter wall and the mucosa of the urethra by means of a hollow mandrin (19) appropriately placed in the lumen (18) of the catheter, the mandrin thereby blocking off the lumen of the catheter. The urine continues to flow in this manner until it encounters an opening (20) in the mandrin which permits the urine to flow into and through the lumen of the hollow mandrin. In a variation on this last embodiment the mandrin (19) possesses a narrower central section (23), which permits, in that area, some urine flow between the outer surface of the mandrin (19) and the inner surface of the catheter wall (1), in order to optimize the irrigating effect. In a further embodiment of this invention, a sealing ring (22), located after the farthest window from the bladder, prevents the urine from flowing past it between the catheter wall and the mucousa of the urethra to the beginning of the urethra. As mentioned above, the catheter tip (2) can be retained in the bladder through inflation of a balloon (3), as shown in FIGS. 1-3. On the other hand, other retention means may also be employed, such as the "Casper-tip" shown in FIG. 5, or those according to Pezzer and Malecot (not depicted).

Other features and advantages of the invention are discussed in the further description and the drawings, as well as in the subclaims.

FIG. 1 a first embodiment of the invention shown in longitudinal cross-section of the catheter located in the bladder and urethra.

FIG. 2 another embodiment of the invention with a condom urinal, in longitudinal cross-section

FIG. 3 the catheter in plan view

FIG. 4 a portion of the window-equipped region of the catheter in plan view

FIG. 5 longitudinal cross-section of a catheter with a "Casper-tip" and a mandrin

FIG. 6 longitudinal cross-section of a catheter with a "Casper-tip" and a mandrin, the latter having a narrower central section

According to the embodiment depicted in FIG. 1, the tip (2) of the catheter is held in the bladder by a balloon (3) which, once tip and balloon are introduced into the bladder, is inflated with air or liquid through the inflation channel (4). The inflation channel (4) can lie largely unsecured in the lumen (18) of the catheter, ultimately passing through the wall (1) of the catheter to connect to the inflation tap (5). Where it passes through the urethra, the catheter wall (1) is provided with windows (9). The urine can flow through these windows in the direction indicated by reference numeral 12, and thereby irrigate the urethral mucous membranes.

In the embodiment depicted in FIG. 2 the small quantity of which manages to flow toward the outside of the body between the urethral mucous membranes and the catheter wall is captured by a condom urinal (13), and flows through the drain tap (14) to a not-depicted drainage system.

FIG. 3 is a plan view of the catheter, showing windows (9) arranged in rows against a cross-section of the bladder and urethral regions.

FIG. 4 shows a window-equipped section of the catheter with longitudinal rows of relatively large windows which would overlap each other, were neighboring rows not staggered. Due to the size of the windows, the catheter wall here is significantly weakened, and is therefore preferably made of a stronger material in this region.

In the embodiment depicted in FIG. 5 a hollow mandrin (19) is shown in longitudinal cross-section. The tip of this hollow mandrin is closed, but some millimeters from the tip the mandrin's wall has one or more openings into the mandrin's lumen. As shown in FIG. 5 the hollow mandrin (19) can be positioned in the catheter lumen (18) in such a way that the mandrin's closed tip blocks off the catheter lumen (18) between the catheter lumen's penultimate and last windows. In this way the urine is forced, at least in this area, to flow between the windowed catheter wall and the wall of the urethra. The urine can return to the catheter lumen through the last window, passing from there into the mandrin lumen through the mandrin opening (20), and thence flowing through the mandrin lumen to a disposal system (not shown).

If the mandrin is equipped with a tip capable of blocking the catheter lumen, with this tip followed by a narrower central section in the region of the windows, and the tip of the mandrin in positioned in the vicinity of the first window, then, as shown in FIG. 6, the urine flow will irrigate both the urethral mucous membranes as well as the interior of the catheter wall. In an embodiment without this narrower central section (not shown) the irrigate would be restricted to the urethral mucosa and the exterior of the catheter wall.

Adjacent to the last window, i.e. the one closest to the orifice of the urethra, but just beyond it, i.e. closer to the orifice of the urethra, there is a sealing ring (22), preferably made of a foam-like material, which may contain a substance with oligodynamic properties.

1. catheter wall

2. catheter tip

3. balloon

4. inflation channel for the balloon

5. inflation tap for the inflation channel

6. inner wall of the bladder

7. prostate/sphincter region

8. urethral wall/mucous membranes

9. [catheter wall] window

10. catheter end

11. tip of penis

12. direction of urine flow

13. wall of the condom catheter

14. condom catheter drain tap

15. condom sleeve

16. urine entry opening of the catheter (plan view)

17. window of the catheter wall (side view)

18. catheter lumen

19. mandrin

20. mandrin opening

21. "Casper tip" of catheter

22. sealing ring

23. narrower central section of the mandrin

24. space between the inner surface of the catheter and the outer wall of the mandrin