Respiratory circuit terminal for a unilimb respiratory device

A respiratory terminal filter assembly comprising a filter device and a terminal, said filter device comprising

• a filter housing having a proximal end and a distal end, said filter housing containing a first filter chamber and a second filter chamber, said first filter chamber not being in fluid communication with said second filter chamber;
• filter means in said first and second filter chambers;
• a proximal inner conduit and a proximal outer conduit at said proximal end of said filter housing, said proximal outer conduit surrounding said proximal inner conduit to form a proximal expiratory of inspiratory inner fluid path within the interior of said proximal inner conduit and a proximal outer expiratory or inspiratory fluid path in the region between the exterior of said proximal inner conduit and the interior of said proximal outer conduit;
• a distal inner conduit and a distal outer conduit at said distal end of said filter housing, said distal outer conduit surrounding said distal inner conduit to form a distal expiratory or inspiratory inner fluid path within the interior of said distal inner conduit and a distal outer expiratory or inspiratory fluid path in the region between the exterior of said distal inner conduit and the interior of said distal outer conduit;
• said first filter chamber being in fluid communication with said proximal inner fluid path and said distal inner fluid path;
• and
• said second filter chamber being in fluid communication with said proximal outer fluid path and said distal outer fluid path,
• said terminal comprising
• a unitary housing constructed of a rigid material, said unitary housing having a first port, a second port, a third port, a fourth port,
• an outer tube, and an inner tube, said outer tube and inner tube each having a first end and a second end, at least a portion of said inner tube being disposed within said outer tube, said second end of said inner tube having a smaller external diameter than the internal diameter of said second end of said outer tube,
• said second end of said outer tube forming said first port, said second end of said inner tube forming said second port,
• said first end of said inner tube being sealably bonded into said third port, wherein fluid entering said third port may only pass through said inner tube and exit from said second port, said first end of said outer tube forming said forth port, said third and fourth ports entering said housing a different locations, wherein fluid entering said fourth port may only pass between the interior of said outer tube and the exterior of said inner tube and may only exit through said first port;
• wherein said proximal outer conduit is connected to said first port and said proximal inner conduit is connected to said second port.

A respiratory or ventilator proximal terminal for use in a unilimb artificial respiration device, comprising:

• a unitary housing constructed of a rigid material, said housing including a first port, a second port, a third port, a fourth port, an outer tube and an inner tube;
• said inner tube being at least partially disposed within said outer tube, said outer tube and inner tube each having a first end and a second end, the external diameter of said second end of said inner tube being smaller than the internal diameter of said second end of said outer tube, said second end of said inner tube being disposed within said second end of said outer tube to form an inner inspiratory or expiratory fluid path within the interior of said second end of said inner tube and an outer inspiratory or expiratory fluid path in the region between the exterior of said inner tube and the interior of said second end of said outer tube;
• said second end of said outer tube being connected to said first port, said second end of said inner tube being connected to said second port, said first end of said inner tube being connected to said third port and said first end of said outer tube being connected to said fourth port, said third and fourth ports entering said housing at different locations;
• wherein fluid entering said third port passes through said inner tube into said inner inspiratory or expiratory fluid path and may only exit through said second port, and fluid entering said fourth port passes through said outer inspiratory or expiratory fluid path and may only exit through said first port.

A respiratory conduit assembly for use in an assisted ventilation system having an inspiratory gas input and an exhaust outlet, said respiratory conduit assembly comprising:

• a unilimb respiratory conduit, and
• a proximal terminal, said unilimb respiratory conduit capable of being connected to and disconnected from said proximal terminal by a user at the site of use,
• said unilimb respiratory conduit having a distal end and a proximal end, said unilimb respiratory conduit including:
• an outer flexible tube,
• an inner flexible tube, said outer flexible tube and inner flexible tube each having a proximal end and a distal end;
• the outer diameter of said inner flexible tube being smaller than the inner diameter of said outer flexible tube, said inner flexible tube being at least partially disposed within said outer flexible tube, said distal end of said inner flexible tube being disposed within and in direct fluid communication with said outer flexible tube, and
• a proximal fitting located at said proximal end of said unilimb respiratory conduit, said proximal fitting comprising an inner pipe and an outer pipe maintained in fixed coaxial spaced relationship by spacing means, said outer pipe and inner pipe each having a proximal end and a distal end, wherein said distal end of said inner pipe is operably connected to said proximal end of said inner flexible tube and said distal end of said outer pipe is operably connected to said proximal end of said outer flexible tube;
• said proximal terminal having a unitary housing constructed of a rigid material, said housing including a first port, a second port, a third port, a fourth port, an outer terminal tube and an inner terminal tube;
• said inner terminal tube being at least partially disposed within said outer terminal tube, said outer and inner terminal tubes each having a first end and a second end, the external diameter of said second end of said inner terminal tube being smaller than the internal diameter of said second end of said outer terminal tube, said second end of said inner terminal tube being disposed within said second end of said outer terminal tube to form an inner terminal fluid path within the interior of said second end of said inner terminal tube and an outer fluid path in the region between the exterior of said inner terminal tube and the interior of said second end of said outer terminal tube;
• said second end of said outer terminal tube being connected to said first port, said second end of said inner terminal tube being connected to said second port, said first end of said inner terminal tube being connected to said third port and said first end of said outer terminal tube being connected to said fourth port, said third and fourth ports entering said housing at different locations;
• wherein, said unilimb respiratory conduit can be connected to said proximal terminal by operably connecting said first port of said proximal terminal to said outer pipe of said proximal fitting and operating connecting said second port of said proximal terminal of said inner pipe of said proximal fitting to form a first fluid path through said third port, said inner terminal tube, said second port, said inner pipe and said inner flexible tube and a second fluid path through said fourth port, said outer respiratory fluid path, said first port, the region between the exterior of said inner pipe and the interior of said outer pipe, and the region between the exterior of said inner flexible tube and the interior of said outer flexible tube,
• one of said third and fourth ports of said proximal terminal capable of being operably connected to the inspiratory gas input of the assisted ventilation system while the other one of said third and fourth ports of said proximal terminal is simultaneously operably connectable to the exhaust outlet of the assisted ventilation system, and said distal end of said unilimb respiratory conduit is capable of being operably connected to an airway device connected to a mammal to provide inspiratory gases to the mammal through one of said first and second fluid paths and exhaust expiratory gases from the mammal through the other of said first and second fluid paths.