Apparatus for equalizing air pressure in an air respiratory system

Abstract

A humidifier apparatus for operating at an air pressure is disclosed for use with a respiratory therapy breathing apparatus that provides a breathable gas supply to patients requiring higher concentrations of liquid vapor and gas pressure. The humidifier apparatus includes a volume of liquid in fluid communication with a humidifier cartridge via a conduit. The conduit enables air to flow therethrough to equalize air pressure between the humidifier cartridge and the volume of liquid in response to liquid being supplied to the humidifier cartridge.

1 . A humidifier apparatus for use in a respiratory therapy circuit having a breathable gas supply, the apparatus comprising: 
 a humidifier cartridge defining an interior space adapted to hold liquid, the humidifier cartridge adapted to allow passage of breathable gas through the interior space so as to be humidified by liquid in the interior space, the humidifier cartridge having a liquid inlet coupled to a float to selectively control flow of liquid into the interior of the humidifier cartridge to approximately a desired level;    a volume of liquid near the humidifier cartridge;    a first line coupling a lower extent of the volume of liquid to the liquid inlet; and    a second line coupling the interior space of the humidifier cartridge above the desired level to a space adjacent an upper extent of the volume of liquid, whereby liquid flows into the interior of the humidifier cartridge through the liquid inlet and is maintained at approximately the desired level as the volume of liquid reduces.    
   
   
       2 . The humidifier apparatus of  claim 1 , the upper extent of the volume of liquid initially being above the desired level of liquid in the humidifier cartridge.  
   
   
       3 . The humidifier apparatus of  claim 2 , the lower extent of the volume of liquid initially being above the desired level of liquid in the humidifier cartridge.  
   
   
       4 . The humidifier apparatus of  claim 1  further comprising a container holding the volume of liquid, the container having an upper end and a lower end defined in relation to the container being coupled to the first and second lines, the lower extent of the volume of liquid being defined at the lower end of the container and the space adjacent the upper extent of the volume of liquid being defined at the upper end of the container, the first line being coupled to the lower extent of the volume of liquid through the lower end of the container and the second line being coupled to the space adjacent the upper extent of the volume of liquid through the upper end of the container.  
   
   
       5 . The humidifier apparatus of  claim 4 , the upper extent of the liquid initially being adjacent the upper end of the container.  
   
   
       6 . The humidifier apparatus of  claim 4 , the upper extent of the volume of liquid being adjacent the upper end of the container until the container is nearly drained.  
   
   
       7 . The humidifier apparatus of  claim 4 , the container being a bag.  
   
   
       8 . The humidifier apparatus of  claim 1 , the humidifier cartridge having a top portion and an oppositely disposed bottom with the interior space being situated therebetween, the interior space of the humidifier cartridge above the desired level within the humidifier cartridge being proximate the top portion of the humidifier cartridge.  
   
   
       9 . The humidifier apparatus of  claim 8  further comprising an air outlet associated with the top portion of the humidifier cartridge, the second line being coupled to the air outlet.  
   
   
       10 . The humidifier apparatus of  claim 8 , the liquid inlet being associated with the top portion of the humidifier cartridge  
   
   
       11 . The humidifier cartridge of  claim 8 , the bottom of the humidifier cartridge being configured to operationally engage a heating unit to receive heat therefrom.  
   
   
       12 . A method of providing liquid for humidifying a breathable gas in a respiratory therapy circuit comprising: 
 flowing liquid from a lower extent of a volume of liquid to an interior space of a humidifier cartridge to approximately a desired level of liquid therein, the cartridge being adapted to allow passage of a breathable gas through the interior space so as to be humidified by liquid in the interior space;    venting the interior space of the humidifier cartridge above the desired level to a space adjacent an upper extent of the volume of liquid;    maintaining the liquid within the humidifier cartridge at approximately the desired level as the volume of liquid reduces.    
   
   
       13 . The method of  claim 12  further comprising situating the volume of liquid such that the upper extent thereof is initially above the desired level of liquid in the humidifier cartridge.  
   
   
       14 . The method of  claim 13  further comprising situating the volume of liquid such that the lower extent thereof is initially above the desired level of liquid in the humidifier cartridge.  
   
   
       15 . The method of  claim 12  wherein the volume of liquid is held within a container, the method further comprising operatively coupling the humidifier cartridge and container such that liquid flows therefrom to the interior space of the humidifier cartridge and the interior space thereof vents into the container.  
   
   
       16 . The method of  claim 15  wherein the container is a bag.