Catheter with multiple heating/cooling fibers employing fiber spreading features

• US 6,450,990 B1
• Filed: 04/19/1999
• Issued: 09/17/2002
• Est. Priority Date: 08/13/1998
• Status: Expired due to Term

• Current Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Original Assignee: Alsius Corporation
• Inventors: Walker, Blair D., Evans, Scott M., Balding, David P., Shimada, Lynn M., Hallam, Gregg
• Primary Examiner(s): Nguyen, Anhtuan T.
• Assistant Examiner(s): Thompson, Michael M
• Application Number:
  US09/294,080
• Time in Patent Office: 1,247 Days
• Field of Search: 604/26, 604/28, 604/43, 604/500, 604/6.13, 604/4.01, 604/22, 604/96.01, 604/113, 604/290, 604/291, 606/20-23
• 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, each hollow fiber forming a sealed fluid path;

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 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.

6. The catheter of claim 5, where each fiber has an outer diameter of about 0.022 inches and an inner diameter of about 0.0185 inches.

7. A heat exchange catheter, comprising:

a first fluid conduit having a proximal end and a distal end;

a second fluid conduit having a proximal end and a distal end;

multiple hollow fibers having substantially coterminous proximal and distal ends, each fiber defining a sealed fluid pathway between the proximal end and the distal end of each fiber, each fiber being sealed such that neither liquid nor air may pass through the fiber other than through the pathway;

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

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

an actuating structure wherein the actuating structure comprises an inner tube and an outer tube with the inner tube being slideable within the outer tube, sliding of the inner tube within the outer tube encouraging spreading of the fibers.

8. The catheter of claim 7, the distal fluid transfer housing including a distally positioned fluid reservoir forming at least part of the sealed fluid path between the fibers'"'"' distal ends and the second fluid conduit.

9. The catheter of claim 7 wherein

the inner tube extends from the proximal fluid transfer housing to the distal fluid transfer housing with at least a portion of the second fluid conduit being disposed in the inner tube; and

the outer tube at least partially surrounds the inner tube with at least a portion of the first fluid conduit being disposed between the outer tube and the inner tube.

10. The catheter of claim 9, the inner tube having a shape such that the inner tube contacts and tends to spread the fibers apart in the absence of straightening forces acting on the inner tube.

11. The catheter of claim 7, the fibers having pre-formed shapes and being connected with the proximal and distal fluid transfer housings such that internal forces within the fibers together with external forces exerted by the proximal and distal fluid transfer housings tend to spread the fibers apart.

12. The catheter of claim 11, the shape of each fiber being at least partially dependent on the temperature of each fiber.

13. The catheter of claim 7, each fiber having an outer diameter of about 0.020 to about 0.024 inches and an inner diameter of about 0.016 to about 0.0195 inches.

14. The catheter of claim 13, each fiber having an outer diameter of about 0.022 inches and an inner diameter of about 0.0185 inches.