Catheter with multiple heating/cooling fibers employing fiber spreading features

• US 20010031946A1
• Filed: 06/11/2001
• Published: 10/18/2001
• Est. Priority Date: 08/13/1998
• Status: Abandoned Application

• Current Assignee: Blair D. Walker, David P. Balding, Gregg Hallam, Lynn M. Shimada, Scott M. Evans
• Original Assignee: Blair D. Walker, David P. Balding, Gregg Hallam, Lynn M. Shimada, Scott M. Evans
• Inventors: Walker, Blair D., Hallam, Gregg, Evans, Scott M., Balding, David P., Shimada, Lynn M.
• Application Number:
  US09/878,863
• Publication Number:
  US 20010031946A1
• Time in Patent Office: Days
• US Class Current: 604/113
• CPC Class Codes: A61B 2018/00011 with fluids
• CPC Class Codes: A61F 2007/0054 with a closed fluid circuit, e.g. hot water
• CPC Class Codes: A61F 2007/126 for invasive application, e.g. for introducing into blood vessels
• CPC Class Codes: A61F 7/12 Devices for heating or cooling internal body cavities
• CPC Class Codes: A61F 7/123 using a flexible balloon containing the thermal element
• CPC Class Codes: A61M 1/3623 Means for actively controlling temperature of blood
• CPC Class Codes: A61M 1/369 Temperature treatment
• CPC Class Codes: A61M 2205/36 related to heating or cooling
• CPC Class Codes: A61M 25/00 Catheters; Hollow probes dilators A61M29/00; peritoneal catheters A61M1/285; tracheal tubes A61M16/04; for drainage A61M27/00; for uterus, vagina or rectum A61M31/00 ; for measuring or testing A61B; materials for catheters A61L29/00
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media

Abstract

A catheter using multiple hollow fibers to carry a heating/cooling fluid employs fiber spreading features to improve heat transfer and help prevent clotting of body fluids within which the catheter is immersed. The catheter includes a length of outer tube surrounding an inner tube. The inner tube conveys fluids in one direction, and the passageway between inner and outer tubes conveys fluids in the opposite direction. The inner and outer tubes have proximal distal ends. The distal end is closed, but the proximal end is open to permit introduction of a heating or cooling fluid into the inner tube, and withdrawal of the fluid from the passageway between the inner and outer tubes. At the tubes'"'"' distal end resides a proximal fluid transfer housing coupled to multiple hollow heat exchange fibers. The distal ends of these fibers may be commonly connected to a distal fluid transfer housing and optional reservoir, which cooperatively return fluid to the passageway between inner and outer tubes. In another embodiment, each fiber includes both outflowing and return lumens, enabling the fibers'"'"' distal ends to freely move about. In another embodiment, each fiber proceeds outward from the proximal fluid transfer housing, and returns back to form a loop. In each different embodiment, the invention includes one or more actuating structures to spread the fibers. The actuating structure may include, for example, fiber shaping, a retractable spreading member, elastic bias built into the fibers, etc.

Claims

1. A heat exchange catheter, comprising:

first and second fluid conduits each having a proximal and a distal end;

multiple hollow fibers of substantially equal length, the fibers having substantially coterminous proximal and distal ends;

a proximal fluid transfer housing forming a sealed fluid path between the fibers'"'"' proximal ends and the first conduit;

a distal fluid transfer housing forming a sealed fluid path between the fibers'"'"' distal ends and the second conduit; and

an actuating structure to spread the fibers under predetermined conditions.

2. The catheter of

claim 1

, the distal fluid transfer housing including a distally positioned fluid reservoir, where the distal fluid transfer housing forms a sealed path between the fibers'"'"' distal ends and the second conduit via the fluid reservoir.

3. The catheter of

claim 1

, the catheter including an outer tube and an inner tube, the outer tube surrounding the inner tube, where the inner tube provides the second fluid conduit and proceeds from the proximal fluid transfer housing to the distal fluid transfer housing in parallel along with the fibers, and a passageway between the inner and outer tubes provides the first fluid conduit.

4. The catheter of

claim 3

, the actuating structure comprising:

a coupling between the proximal fluid transfer housing and the inner tube being such that the proximal fluid transfer housing surrounds the inner tube while leaving the inner tube free to slide toward and away from the distal end, the coupling permitting the inner tube to be slidably withdrawn causing withdrawal of the distal fluid transfer housing and the fibers'"'"' distal ends and consequently spreading the fibers.

5. The catheter of

claim 4

, the fibers being grouped and braided along the inner tube.

6. The catheter of

claim 4

, at least some of the fibers being joined at one or more intermediate points between their distal and proximal ends.

7. The catheter of

claim 4

, further comprising:

an intermediate band surrounding the fibers at a point between the proximal and distal fluid transfer housings, such that sliding withdrawal of the inner tube withdraws the fluid reservoir and the fibers'"'"' distal ends and consequently curves the fibers in to an “

S”

shape.

8. The catheter of

claim 1

, the actuating structure comprising shaping of the fibers providing the fibers with predetermined shapes.

9. The catheter of

claim 8

, the shaping comprising:

pre-shaping built into the fibers to urge them into the predetermined shapes, the predetermined conditions comprising lack of straightening force upon the fibers.

10. The catheter of

claim 8

, the shaping comprising:

shape memory built into the fibers to urge them into the predetermined shapes, the predetermined conditions comprising the fibers having temperatures in a predetermined temperature range.

11. The catheter of

claim 8

, the predetermined shapes comprising spiral windings.

12. The catheter of

claim 11

, the spiral winding of each fiber having an amplitude and phase common to all fibers.

13. The catheter of

claim 11

, the spiral winding of each fiber having an amplitude common to all fibers, where a phase of the spiral windings varies among the fibers.

14. The catheter of

claim 8

, the predetermined shapes comprising outward bowing of the fibers.

15. The catheter of

claim 3

, the actuating structure comprising shaping of the inner tube providing the inner tube with a predetermined shape.

16. The catheter of

claim 15

, the shaping comprising:

pre-shaping built into the inner tube urging it into the predetermined shape, the predetermined conditions comprising lack of straightening force upon the inner tube.

17. The catheter of

claim 15

, the shaping comprising:

shape memory built into the inner tube urging it into the predetermined shape, the predetermined conditions comprising the inner tube having a temperature in a predetermined temperature range.

18. The catheter of

claim 15

, the predetermined shape comprising a spiral winding.

19. The catheter of

claim 1

, where each fiber has an outer diameter of about 0.020-0.024 inches and an inner diameter of about 0.016-0.0195 inches.

20. The catheter of

claim 19

, where each fiber has an outer diameter of about 0.022 inches and an inner diameter of about 0.0185 inches.

21. A heat exchange catheter, comprising:

fluid supply and fluid return conduits each having a proximal and a distal end;

multiple substantially parallel hollow fibers each fiber having a distal end, the fibers having substantially collocated proximal ends, each fiber including a continuous fluid path proceeding from a fluid supply opening at its proximal end to its distal end and then to a fluid return opening at the proximal end; and

a fluid transfer housing defining a sealed fluid path between the fibers'"'"' fluid supply openings and the fluid supply conduit, and also defining a sealed fluid path between the fibers'"'"' fluid return openings and the fluid return conduit.

22. The catheter of

claim 21

, the catheter including an outer tube and an inner tube, the outer tube surrounding the inner tube, where the inner tube provides the fluid supply conduit, and a passageway between the outer and inner tubes provides the fluid return conduit.

23. The catheter of

claim 21

, the fibers having shaping built into the fibers urging them apart responsive to selective input comprising an absence of fiber straightening pressure.

24. The catheter of

claim 23

, the shaping comprising a temperature dependent shape memory.

25. The catheter of

claim 22

, further comprising:

a spreading member coupled to a retraction line that runs within the outer tube from its distal end to its proximal end, the spreading member being substantially central to the fibers, where withdrawal of the retraction line pulls the spreading member toward the common proximal ends of the fibers to spread the fibers.

26. The catheter of

claim 25

, the spreading member comprising a ball.

27. The catheter of

claim 21

, further comprising:

an inflatable balloon substantially central to the fibers, where inflation of the balloon spreads the fibers by moving them outward; and

an inflation line having a source end and a remote end, the inflation line'"'"'s remote end coupled to the inflatable balloon via the fluid transfer housing to convey an inflation fluid between the balloon and an inflation source coupled to the inflation line'"'"'s source end.

28. A heat exchange catheter, comprising:

supply and return conduits each having a proximal and a distal end;

multiple hollow fibers each having a coolant supply end and a coolant return end proximally located to form a distal loop of fiber; and

a fluid transfer housing defining a sealed fluid path between the coolant supply end of each fiber and the supply conduit, and also defining a sealed fluid path between the coolant return end of each fiber and the return conduit.

29. The heat exchange catheter of

claim 28

, the catheter including an outer tube and an inner tube, the outer tube surrounding the inner tube, where the inner tube provides one of the conduits, and a passageway between the outer and inner tubes provides the other return conduit.

30. The heat exchange catheter of

claim 28

, the fibers'"'"' supply and return ends being coupled to the fluid transfer housing at corresponding coupling points, all coupling points cooperatively forming a circle.

31. The heat exchange catheter of

claim 28

, the fibers'"'"' supply and return ends being coupled to the fluid transfer housing at corresponding coupling points, where the coupling points of the fibers'"'"' return ends form a hollow shape surrounding the coupling points of the fibers'"'"' supply ends.

32. The catheter of

claim 28

, the fibers being between four and ten in number.

33. The catheter of

claim 32

, the fibers being seven in number.

34. The catheter of

claim 28

, where each fiber has an outer diameter of about 0.020-0.024 inches and an inner diameter of about 0.016-0.0195 inches.

35. The catheter of

claim 34

, where each fiber has an outer diameter of about 0.022 inches and an inner diameter of about 0.0185 inches.

36. A heat exchange catheter comprising:

a body communicating with a source of coolant via coolant supply and coolant return pathways, the body defining a distal end;

plural hollow fibers extending away from the distal end, each fiber defining a respective distal portion and a coolant supply path for conveying coolant from the coolant supply pathway of the body to the distal portion, each fiber also defining a respective coolant return path for conveying coolant from the respective distal portion to the coolant return pathway of the body.

37. The catheter of

claim 36

, where each fiber includes at least two lumens, the lumens establishing the coolant supply and return paths of the fiber.

38. The catheter of

claim 36

, where each fiber is configured in a loop, a first segment of the loop establishing the coolant supply path of the fiber and a second segment of the loop establishing the coolant return path of the fiber.

39. A heat exchange catheter, comprising:

a first conveyance means for conveying fluid along a first path;

a second conveyance means for conveying fluid along a second path;

multiple substantially parallel, hollow fibers, the fibers having substantially coterminous proximal and distal ends;

a fluid transfer housing means for forming a sealed fluid path between the fibers'"'"' proximal ends and the first conveyance means;

a redirecting means for forming a sealed fluid path between the fibers'"'"' distal ends and the second conveyance means; and

actuating means for spreading the fibers under predetermined conditions.

40. A heat exchange catheter, comprising:

a first conveyance means for conveying fluid along a first path;

a second conveyance means for conveying fluid along a second path;

multiple substantially parallel hollow fibers each fiber having a distal end, the fibers having substantially collocated proximal ends, each fiber including a continuous fluid path proceeding from a fluid supply opening at its proximal end to its distal end and then to a fluid return opening at the proximal end; and

a fluid transfer housing means for providing a sealed fluid path between the fibers'"'"' fluid supply openings and the first conveyance means and also defining a sealed fluid path between the fibers'"'"' fluid return openings and the second conveyance means.

41. A heat exchange catheter, comprising:

a first conveyance means for conveying fluid along a first path;

a second conveyance means for conveying fluid along a second path;

multiple hollow fibers each having fluid supply and return ends proximately located to form a loop of fiber; and

a fluid transfer housing means for providing a sealed fluid path between the supply end of each fiber and the first conveyance means, and also defining a sealed fluid path between the return end of each fiber and the second conveyance means.

42. A method of operating an elongate heat exchange catheter that includes supply and return fluid conduits each having a proximal and a distal end;

multiple substantially parallel, hollow fibers of substantially equal length, the fibers having substantially coterminous proximal and distal ends;

a proximal fluid transfer housing forming a sealed fluid path between the fibers'"'"' proximal ends and the return conduit;

distal fluid redirecting structure forming one or more sealed fluid paths between the fibers'"'"' distal ends and the return conduit; and

an actuating structure to spread the fibers under predetermined conditions;

the method comprising the operations of;

inserting the catheter into a patient'"'"'s body;

circulating a heat exchange fluid through the catheter; and

spreading the fibers using the actuating structure.

43. The method of

claim 42

, the actuating structure comprising a predetermined pre-shaping built into the fibers, where the spreading operation is performed by the fibers assuming the predetermined shape.

44. The method of

claim 42

, the actuating structure comprising shape memory built into the fibers, the spreading operation being performed responsive to the fibers achieving a temperature in a predetermined temperature range.

45. The method of

claim 42

, the actuating structure comprising a spiral shape built into the fibers, where the spreading operation is performed by circulating the heat exchange fluid through the catheter according to a pulsing pattern to selectively elongate the fibers.

46. The method of

claim 45

, the pulsing pattern being periodic.

47. The method of

claim 42

, where:

the supply conduit passes through the proximal fluid transfer housing and proceeds with the fibers to a distal fluid transfer housing that provides the redirecting structure;

the actuating structure comprises a spiral shape built into the fibers; and

the spreading operation is performed by circulating the heat exchange fluid through the catheter according to a pulsing pattern to selectively elongate the fibers.

48. The method of

claim 47

, the pulsing pattern being periodic.

49. The method of

claim 42

, the insertion operation comprising slidably inserting the catheter into the body through an introducer sheath, the sheath holding the fibers together during the insertion operation.

50. A method for shaping a fiber bundle for a heat exchange catheter, the fiber bundle including proximal and distal fluid transfer housings interconnected by multiple hollow heat exchange fibers, the method comprising the operations of:

constructing a spacer defining multiple slits radially disposed about a periphery of the spacer;

positioning the fibers by placing the slider among the fibers and sliding each fiber into one of the slits;

heating the fibers to a prescribed temperature while the fibers are being positioned by the spacer; and

cooling the fibers.

51. The method of

claim 50

, the spacer having a substantially flat disk shape.

52. The method of

claim 50

, the heating operation comprising placing the fiber bundle into an oven and heating according to a predetermined plan of one or more temperatures and corresponding durations.

53. The method of

claim 50

, where the cooling operation comprises immersing the fiber bundle in water.