Nasal cannula assembly with inhalation valves communicating with a deformable reservoir

Abstract

The invention concerns a nasal cannula assembly ( 10 ) adapted to deliver gases to a patient comprising a first compartment ( 1 ) and a second compartment ( 2 ) separated by a separation wall ( 6 ); a pair of nasal prongs ( 5 ) in fluid communication with the first compartment ( 1 ); the first compartment ( 1 ) comprising a first inlet ( 11 ) for introducing a first gas into said first compartment ( 1 ); the second compartment ( 2 ) comprising a second inlet ( 2 ) for introducing a second gas into said second compartment ( 2 ); and the separation wall ( 6 ) comprising at least one valve element ( 3 ) for controlling the passage of gas from the second compartment ( 2 ) to the first compartment ( 1 ). The invention concerns also a breathing assistance apparatus comprising a source of NO gas, and said nasal cannula assembly ( 10 ) in fluid communication with said source of NO gas.

1 . A nasal cannula assembly ( 10 ) adapted to deliver gases to a patient, the nasal cannula assembly ( 10 ) comprising:
 a) a first compartment ( 1 ) and a second compartment ( 2 ) separated by a separation wall ( 6 ),   b) a pair of nasal prongs ( 5 ) in fluid communication with the first compartment ( 1 ),   c) the first compartment ( 1 ) comprising a first inlet ( 11 ) configured to conduct a first gas into said first compartment ( 1 ),   d) the second compartment ( 2 ) comprising a second inlet ( 12 ) configured to conduct a second gas into said second compartment ( 2 ), and   e) the separation wall ( 6 ) comprising at least one valve element ( 3 ) configured to
 permit a passage of gas from the second compartment ( 2 ) to the first compartment ( 1 ) and 
 prevent or limit a passage of gas from the first compartment ( 1 ) to the second compartment ( 2 ). 
   
     
     
         2 . The nasal cannula assembly according to  claim 1 , wherein the separation wall ( 6 ) comprises at least two valve elements ( 3 ). 
     
     
         3 . The nasal cannula assembly according to  claim 1 , wherein the first compartment ( 1 ) comprises a first inlet ( 11 ) forming a side gases entry in fluid communication with a gas transport conduct. 
     
     
         4 . The nasal cannula assembly according to  claim 1 , wherein the nasal cannula assembly further comprises a hollow body ( 4 ) comprising an internal chamber ( 7 ) comprising at least the first compartment ( 1 ). 
     
     
         5 . The nasal cannula assembly according to  claim 4 , wherein at least the first compartment ( 1 ) is part of a hollow body ( 4 ) configured to be capable of acting as a gas conduct or a gas manifold. 
     
     
         6 . The nasal cannula assembly according to  claim 4 , wherein said hollow body ( 4 ) and said pair of nasal prongs ( 5 ) are integrally molded from a soft plastics material. 
     
     
         7 . The nasal cannula assembly according to  claim 4 , wherein the pair of nasal prongs ( 5 ) are detachable from said hollow body ( 4 ) and selected from different sized prongs suitable for different sized patient nares. 
     
     
         8 . The nasal cannula assembly according to  claim 1 , wherein the at least two valve elements ( 3 ) are one-way valves. 
     
     
         9 . The nasal cannula assembly according to  claim 1 , wherein the at least two valve elements ( 3 ) are arranged in the separation wall ( 6 ), directly opposite the pair of nasal prongs ( 5 ). 
     
     
         10 . The nasal cannula assembly according to  claim 1 , wherein the second compartment ( 2 ) comprises a deformable wall ( 14 ). 
     
     
         11 . The nasal cannula assembly according to  claim 1 , wherein the second compartment ( 2 ) forms a deformable-wall reservoir comprising a fully inflated internal volume for the gas of about 0.5 to 5 ml. 
     
     
         12 . The nasal cannula assembly according to  claim 1 , wherein nasal cannula assembly does not comprise a sensor configured to detect an onset of patient inspiration. 
     
     
         13 . The nasal cannula assembly according to  claim 1 , wherein the at least one valve element ( 3 ) is selected from an umbrella valve or a duckbill valve. 
     
     
         14 . The nasal cannula assembly according to  claim 13 , wherein the at least one valve element ( 3 ) has a cracking pressure of 0.5 kPa or less. 
     
     
         15 . The nasal cannula assembly according to  claim 9 , wherein the deformable wall ( 14 ) of the second compartment ( 2 ) has a greater compliance while filling than when the second compartment ( 2 ) is full. 
     
     
         16 . The nasal cannula assembly according to  claim 1 , wherein the pair of nasal prongs ( 5 ) includes an external pillow element ( 8 ) at an end. 
     
     
         17 . The nasal cannula assembly according to  claim 16 , wherein said pillow element ( 8 ) is made of silicone. 
     
     
         18 . The nasal cannula assembly according to  claim 1 , further comprising an expiratory orifice ( 13 ) in the first compartment ( 1 ) defining a fluid communication from an internal chamber ( 7 ) and an external atmosphere. 
     
     
         19 . The nasal cannula assembly according to  claim 9 , further comprising a resistive element ( 9 ) between an internal volume ( 7 ) of the first compartment ( 1 ) and an air or oxygen supply ( 11 ), the resistive element configured to ensure a sufficient pressure drop upon the onset of inhalation to open at least one valve element ( 3 ). 
     
     
         20 . The nasal cannula assembly according to  claim 19 , further comprising a one-way expiratory valve in the expiratory orifice ( 13 ).