Pressure catheter device with enhanced positioning features

• US 5,951,497 A
• Filed: 06/18/1997
• Issued: 09/14/1999
• Est. Priority Date: 09/03/1996
• Status: Expired due to Term

• Current Assignee: Clinical Innovations LLC (Clinical Innovations)
• Original Assignee: Clinical Innovations Associates (Clinical Innovations)
• Inventors: Smith, Steven R., Wallace, Wm. Dean, Cutler, Christopher A.
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): YU, JUSTINE ROMANG
• Application Number:
  US08/878,054
• Time in Patent Office: 818 Days
• Field of Search: 600/587, 600/588, 600/561, 600/591, 600/593, 600/576, 600/585, 600/159, 600/190, 600/170, 600/176, 604/280, 604/905
• US Class Current: 600/587
• CPC Class Codes: A61B 1/303 for the vagina, i.e. vaginoscopes
• CPC Class Codes: A61B 5/035 Intra-uterine probes therefor

Abstract

A pressure catheter for monitoring changes in pressure within the body is comprised of an outer tube containing a fluid channel and a closed air column having a pressure-compliant member which is deformable upon an increase in pressure. A change in pressure deforms the pressure-compliant member, which modifies the pressure in the air column, and is translated to a pressure sensor, which converts the pressure change data to an electrical signal recognizable by a fetal monitor. The outer tube employs a window extending along at least a portion of the side thereof for viewing of bodily fluids moving through the fluid channel from the body in which the catheter is inserted toward the proximal catheter end. The pressure catheter of the present invention is particularly suitable for intrauterine pressure monitoring during labor. Viewing of amniotic fluid through the window facilitates verification of proper catheter tip placement within the amniotic fluid space. Venting closures for facilitating venting of fluid through the channel are also disclosed.

Claims

1. A pressure catheter for detecting changes in pressure within a body comprising:

an elongated outer tube defined by a circumferential wall, having a first end and a second end and encompassing a fluid channel extending longitudinally through an interior of said outer tube, apertures formed through said wall of said outer tube proximate said first end providing communication between an exterior of said elongated outer tube and said interior of said outer tube, at least a portion of said wall of said outer tube lying between said fluid channel and the exterior of said outer tube and located remote from said first end being formed of a light-transmissive material comprising at least one transmissive window along a length of said elongated tube structure;

a closed air column located at least partially within said outer tube, said air column extending longitudinally from proximate said first end of said outer tube to proximate said second end thereof;

a pressure-compliant member proximate said first end of said outer tube, said pressure-compliant member defining an interior chamber in communication with said closed air column, said pressure-compliant member being deformable with a change in fluid pressure external to said elongated outer tube relative to pressure of air within said closed air column; and

said catheter including structure for substantially precluding direct contact of said pressure-compliant member with tissues of said body when inserted thereinto.

2. The pressure catheter of claim 1, further comprising structure for charging a selected volume of air into said closed air column and effecting closure thereof.

3. The pressure catheter of claim 2, wherein said closed air column is located within an elongated inner tube positioned within said elongated outer tube.

4. The pressure catheter of claim 3, wherein said pressure-compliant member comprises a thin-walled balloon formed of flexible material.

5. The pressure catheter of claim 3, wherein said structure for charging said air column includes a housing to which said inner tube is secured in sealing engagement therewith.

6. The pressure catheter of claim 5, wherein said housing includes a port therethrough in fluid communication with said fluid channel, said port having an exterior outlet.

7. The pressure catheter of claim 6, further including a venting closure configured for attachment to said housing over said exterior outlet.

8. The pressure catheter of claim 7, wherein said venting closure includes a pin-hole communicating between said port and an exterior of said venting closure.

9. The pressure catheter of claim 7, wherein said venting closure includes a porous element disposed between said port and an exterior of said venting closure, said porous element being permeable to gases and substantially impermeable to liquids.

10. The pressure catheter of claim 9, wherein said porous element is impermeable to pathogens.

11. The pressure catheter of claim 9, wherein said venting closure further includes a sealing member disposable over a surface of said porous element exposed on said exterior of said venting closure.

12. The pressure catheter of claim 1, further comprising a pressure detection sensor positioned in communication with said closed air column to detect a pressure change in said air column.

13. The pressure catheter of claim 1, further comprising structure disposed within said closed air column for collecting condensation therewithin.

14. The pressure catheter of claim 1, wherein said light-transmissive material of said at least one window is substantially transparent.

15. The pressure catheter of claim 1, wherein said at least one window comprises a plurality of longitudinally-spaced windows of light-transmissive material.

16. The pressure catheter of claim 1, wherein said at least one window of light-transmissive material extends through about a 75 degree arc circumferentially of said outer tube wall.

17. The pressure catheter of claim 1, wherein said at least a portion of said outer tube wall which is formed of light-transmissive material comprises substantially an entire wall of said outer tube.

18. The pressure catheter of claim 1, further comprising a soft, pliant tip formed on said first end of said elongated outer tube for insertion within a body.

19. The pressure catheter of claim 1, further including structure disposed within at least a portion of said closed air column for preventing total occlusion of said air column.

20. An intrauterine pressure catheter comprising:

an elongated outer tube having a plurality of holes formed at a distal end thereof, said outer tube having a fluid channel located therein, at least a portion of a wall of said outer tube lying between said fluid channel and an exterior surface of said elongated outer tube and remote from the distal end thereof comprising at least one window of light-transmissive material along a length of said outer tube;

a soft, pliant tip attached to said distal end of said outer tube;

an elongated inner tube positioned within said elongated outer tube;

a pressure-compliant member in communication with an interior of said inner tube;

an air column defined by the interior of said inner tube and said pressure-compliant member;

structure for charging a selected volume of air into said air column and closing said air column after said charging;

a pressure detection device positioned in communication with said air column after closure thereof for detecting pressure changes therein; and

structure for transmitting pressure detection signals generated by said pressure detection device to a fetal monitor.

21. The intrauterine pressure catheter of claim 20, wherein said pressure-compliant member is a thin-walled balloon of flexible material.

22. The intrauterine pressure catheter of claim 21, wherein said balloon is attached to said inner tube by a resilient structure.

23. The intrauterine pressure catheter of claim 21, further comprising a structure located within said air column for collecting moisture present therein.

24. The intrauterine pressure catheter of claim 23, wherein said moisture-collecting structure comprises an elongated line of hygroscopic material positioned within said inner tube.

25. The intrauterine pressure catheter of claim 24, wherein said hygroscopic material is nylon.

26. The intrauterine pressure catheter of claim 20, further comprising a housing secured to said inner tube and having a first connector element, and wherein said pressure detection device is associated with a second connector element sized to mate with said first connector element in air-tight registration therewith, said first and second connection elements comprising said charging structure.

27. The intrauterine pressure catheter of claim 26, wherein said pressure detection device includes a pressure transducer having a diaphragm exposed to said air column.

28. The intrauterine pressure catheter of claim 26, including locking structure for retaining said first connector element in air-tight registration with said second connector element.

29. The intrauterine pressure catheter of claim 26, wherein one of said first and second connector elements is structured with a male configuration and the other of said first and second connector elements is structured with a female configuration.

30. The intrauterine pressure catheter of claim 26, wherein said housing includes an amnio port opening onto an exterior thereof and in communication with said fluid channel.

31. The intrauterine pressure catheter of claim 30, further including a venting closure configured for attachment to said housing over said amnio port.

32. The intrauterine pressure catheter of claim 31, wherein said venting closure includes a pin-hole communicating between said amnio port and an exterior of said venting closure.

33. The intrauterine pressure catheter of claim 31, wherein said venting closure includes a porous element disposed between said amnio port and an exterior of said closure, said porous element being permeable to gases and substantially impermeable to liquids.

34. The intrauterine pressure catheter of claim 33, wherein said porous element is substantially impermeable to pathogens.

35. The intrauterine pressure catheter of claim 33, wherein the venting closure further includes a sealing member disposable over a surface of said porous element exposed on the exterior of said venting closure.

36. The intrauterine pressure catheter of claim 20, wherein said at least one window is substantially transparent.

37. The intrauterine pressure catheter of claim 20, wherein said at least one window comprises a plurality of longitudinally-spaced windows.

38. The intrauterine pressure catheter of claim 20, wherein said at least one window extends through about a 75 degree arc circumferentially of said outer tube wall.

39. The intrauterine pressure catheter of claim 20, wherein substantially the entire wall of said outer tube comprises a light-transmissive material.

40. The intrauterine pressure catheter of claim 20, further including structure disposed within at least a portion of said air column for preventing total occlusion thereof.

41. A pressure catheter for detecting changes in pressure within a body comprising:

an elongated tube structure defining first and second lumens extending longitudinally therethrough from proximate a first end of said elongated tube structure to proximate a second end thereof, said first lumen opening to an exterior of said catheter proximate said first end of said elongated tube structure, and said elongated tube structure including a wall disposed between said first lumen and an exterior surface of said elongated tube structure, at least a portion of said wall remote from said first end of said elongated tube structure comprising a light-transmissive material comprising at least one light-transmissive window along a length of said elongated tube structure; and

a pressure-compliant member associated with said second lumen proximate said first end, of said elongated tube structure, said pressure-compliant member being deformable with a change in fluid pressure external to said elongated tube structure relative to pressure of air within said second lumen.

42. The pressure catheter of claim 41, further comprising structure for charging a selected volume of air into said second lumen.

43. The pressure catheter of claim 42, wherein said structure for charging said second lumen includes a housing to which said second lumen is secured in sealing engagement therewith.

44. The pressure catheter of claim 43, wherein said housing includes a port therethrough in fluid communication with said first lumen, said port having an outlet on an exterior of said housing.

45. The pressure catheter of claim 44, further including a venting closure configured for attachment to said housing over said exterior outlet on said exterior of said housing.

46. The pressure catheter of claim 45, wherein said venting closure includes a pin-hole communicating between said port and an exterior of said venting closure.

47. The pressure catheter of claim 46, wherein said venting closure includes a porous element disposed between said port and the exterior of said venting closure, said porous element being permeable to gases and substantially impermeable to liquids.

48. The pressure catheter of claim 47, wherein said porous element comprises a hydrophobic material.

49. The pressure catheter of claim 47, wherein said porous element is substantially impermeable to pathogens.

50. The pressure catheter of claim 47, wherein the venting closure further includes a sealing member disposable over a surface of said porous element exposed on the exterior of said venting closure.

51. The pressure catheter of claim 41, wherein said second lumen lies substantially within an inner tube, and said first lumen lies substantially between an exterior of said inner tube and an interior of an outer tube within which said inner tube is at least partially disposed.

52. The pressure catheter of claim 41, wherein said first and second lumens are defined by mutually adjacent first and second tubes.

53. The pressure catheter of claim 41, wherein said pressure-compliant member comprises a thin-walled balloon formed of flexible material.

54. The pressure catheter of claim 41, further comprising a pressure detection sensor positioned in communication with said second lumen to detect a pressure change therein.

55. The pressure catheter of claim 41, further comprising structure disposed within said second lumen for collecting condensation therewithin.

56. The pressure catheter of claim 41, further comprising structure disposed within said second lumen for preventing total occlusion thereof.

57. The pressure catheter of claim 41, wherein said at least one window is substantially transparent.

58. The pressure catheter of claim 41, wherein said at least one window comprises a plurality of longitudinally-spaced windows.

59. The pressure catheter of claim 41, wherein said at least one window extends through about a 75 degree arc circumferentially of said wall.

60. The pressure catheter of claim 41, wherein the light-transmissive wall portion comprises substantially an entire exterior wall of said elongated tube structure.

61. The pressure catheter of claim 41, further comprising a soft, pliant tip formed on said first end of said elongated outer tube structure.