Heat transfer catheters and methods of making and using same

A fluid circulation catheter apparatus comprising in combination:

• inner and outer elongated sleeves, respectively of smaller and larger diameter, and means to position said sleeves in substantially coaxial relationship to one another;
• said outer sleeve having a fluid opening at a proximal end, a sealed distal end, and consisting essentially of a unitary, integral and seamless tubular unit entirely of biaxially-oriented thermoplastic material;
• said inner sleeve having fluid openings at a proximal end and at a distal end, and terminating before the sealed distal end of said outer sleeve, so as to create a fluid passageway between said inner and outer sleeves;
• and further comprising a tubular element of smaller diameter than said inner sleeve running through the interior of said inner sleeve from at least the proximal end of said inner sleeve to the sealed distal end of said outer sleeve.

A multi-lumen catheter for use in a closed loop fluid circulation system to provide tissue temperature maintenance during surgery comprising:

• an elongated catheter having a distal end, a proximal end and a central drainage lumen therein,
• a first concentric circulation lumen about said catheter, and
• a second concentric circulation lumen about said first concentric circulation lumen,
• wherein said first and second concentric circulation lumens comprise an inner elongated sleeve disposed concentrically about said catheter and an outer elongated sleeve disposed concentrically about said inner sleeve, said inner sleeve having a distal end terminating proximally of said distal end of said catheter and said outer sleeve having a distal end extending beyond said distal end of said inner sleeve and terminating proximally of said distal end of said catheter, said distal end of said outer sleeve being sealed to said catheter about its circumference to provide a fluid tight seal, and said first and second concentric circulation lumens being in fluid communication at said distal ends, and
• means providing fluid communication of said first and second concentric circulation lumens with a source of heat exchange fluid to provide a closed loop fluid circulation path from said source through said first and second lumens and returning to said source.

A closed circulation tissue warming or cooling system for maintaining tissue temperatures during cryosurgery comprising:

• a multi-lumen catheter comprising a catheter having a distal end, a proximal end and a central drainage lumen therein, and first and second concentric circulation lumens,
• a source of circulating heat exchange fluid for circulation through said first and second concentric circulation lumens,
• first and second conduits respectively connecting said first and second circulation lumens to the fluid source,
• means for maintaining the temperature of said circulating fluid, and
• fluid flow control means for regulating the flow of said fluid in a closed loop from said fluid source through said first conduit into said first and second circulation lumens through said second conduit and back to said fluid source,
• wherein said first and second concentric lumens comprise an inner sleeve disposed concentrically about said central drainage lumen and an outer sleeve disposed concentrically about said inner sleeve, said inner sleeve having a distal end terminating proximally of said distal end of said central drainage lumen and said outer sleeve having a distal end extending beyond said distal end of said inner sleeve and terminating proximally of said distal end of said central drainage lumen, said distal end of said outer sleeve being sealed to said central drainage lumen.