Claims
- 19. A balloon-free urinary catheter including a tubular retention section (15A) which, in use, locates in the neck of a patient's bladder, and a tubular drainage section (15B) which, in use, is received in the patient's urethra, the retention section having a diameter which is normally greater than the neck of the bladder but being stretchable on the application of an axial force thereto to reduce its diameter to less than that of the urethra to allow the catheter to travel therethrough until the retention section is positioned inside the bladder, the retention section (15A) being constructed so that it will expand and return to its original size on release of the axial force whereby it locates in the neck of the bladder and engages therewith to form a seal, wherein the improvement comprises:
the retention section (15A) and the drainage section (15B) being both made of a braided material comprising structural filaments arranged at a braid angle so that, when the axial force is applied to the catheter, the retention section (15A) and the drainage section (15B) decrease in diameter and increase once the axial force is removed or reversed.
- 20. A urinary catheter as claimed in claim 19, wherein the braid angle of each of the retention section (15A) and the drainage section (15B) is different so that the retention section (15A) and the drainage section (15B) will expand differentially on release of the axial force applied to the retention section.
- 21. A urinary catheter as claimed in claim 20, wherein the retention section (15A) is of a greater diameter than the drainage section (15B).
- 22. A urinary catheter as claimed in claim 19, further comprising:
locating means (16) incorporated into the distal end of the retention section (15A) against which the axial force can be applied to stretch the retention section and reduce the diameter of the retention section.
- 23. A urinary catheter as claimed in claim 22, wherein the locating means (16) is made of a shape memory metal.
- 24. A urinary catheter as claimed in claim 22, wherein the locating means is made of a polymeric material such as nylon, polypropylene, polyethylene, polyearbonate or PTFE.
- 25. A urinary catheter as claimed in claim 19, further comprising:
spring means incorporated into the retention section (15A) to assist in its recovery to its original diameter on release of the axial force.
- 26. A urinary catheter as claimed in claim 25, wherein the spring means is radially expandable.
- 27. A urinary catheter as claimed in claim 26, wherein the spring means is made of a polymer material.
- 28. A urinary catheter as claimed in claim 27, wherein the spring means is made of one of polypropylene, nylon, polyurethane and polyethylene.
- 29. A urinary catheter as claimed in claim 19, further comprising:
a flexible bead (16) provided around the distal end of the retention section (15A) to restore the retention section to its original shape on release of the axial force.
- 30. A urinary catheter as claimed in claim 29, wherein the bead (16) is made of an elastomeric polymer.
- 31. A urinary catheter as claimed in claim 19, wherein the outer diameter of the tubular retention section (15A), in its relaxed condition, is in the range from about 12-30 mm.
- 32. A urinary catheter as claimed in claim 19, wherein the outer diameter of the tubular drainage section (15B) is in the range from about 5-12 mm.
- 33. A urinary catheter as claimed in claim 19, wherein the diameter of the retention section increases on the removal of the axial force until the braid angle in relation to the longitudinal axis of the catheter reaches a critical angle.
- 34. A urinary catheter as claimed in claim 33, wherein the critical angle is tan−1{square root}2=54.73°.
- 35. A urinary catheter as claimed in claim 19, wherein the catheter is made of thin walled polyurethane tubing.
- 36. A urinary catheter as claimed in claim 19, further comprising:
a valve is located in the proximal end of the catheter.
- 37. A balloon-free urinary catheter comprising:
a tubular retention section (15A) which, in use, locates in the neck of a patient's bladder, the retention section having a diameter which is normally greater than the neck of the bladder but being stretchable on the application of an axial force thereto to reduce the diameter of the retention section to less than that of the urethra to allow the catheter to travel therethrough until the retention section is positioned inside the bladder, the retention section (15A) being constructed so that it will expand and return to its original size on release of the axial force whereby it locates in the neck of the bladder and engages therewith to form a seal; and a tubular drainage section (15B) which, in use, is received in the patient's urethra, wherein the retention section (15A) and the drainage section (15B) are both made of a braided material including structural filaments arranged at a braid angle so that, when the axial force is applied to the catheter, the retention section (15A) and the drainage section (15B) decrease in diameter and once the axial force is removed or reversed increase in diameter.
Priority Claims (1)
Number |
Date |
Country |
Kind |
0019107.2 |
Aug 2000 |
GB |
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit f priority of International Application No. PCT/GB01/03434 filed on Jul. 31, 2001 which claims the benefit of GB Application No. 0019107.2 filed on Aug. 3, 2000, the entire contents of which are incorporated herein by reference.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/GB01/03434 |
7/31/2001 |
WO |
|