Breathing assistance assemblies suitable for long term no therapy
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 breathing assistance apparatus comprising:
a) a nasal cannula assembly ( 10 ) adapted to deliver gases to a patient, the nasal cannula assembly ( 10 ) comprising:
A) a hollow body ( 4 ) configured to be capable of acting as a gas conduct or a gas manifold and comprising an internal chamber ( 7 ) defining a first compartment ( 1 ),
B) the first compartment ( 1 ) and a second compartment ( 2 ) separated by a separation wall ( 6 ),
C) a pair of nasal prongs ( 5 ) in fluid communication with the first compartment ( 1 ),
D) the first compartment ( 1 ) comprising a first inlet ( 11 ) forming a side gases entry in fluid communication with a gas transport conduct and configured to conduct a first gas into said first compartment ( 1 ),
E) the second compartment ( 2 ) having a fully inflated internal volume for a gas of about 0.5 to 5 ml, the second compartment ( 2 ) comprising,
a second inlet ( 12 ) configured to conduct a second gas into said second compartment ( 2 ), and
a deformable wall ( 14 ) having greater compliance while filling than when the second compartment ( 2 ) is full,
F) the separation wall ( 6 ) comprising two, one-way, duckbill or umbrella valves ( 3 ), with a cracking pressure of 0.5 kPa or less, which are oriented and arranged in the separation wall ( 6 ) directly opposite the pair of nasal prongs ( 5 ) to thereby be capable of
permitting a passage of gas from the second compartment ( 2 ) to the first compartment ( 1 ) and
preventing or limiting a passage of gas from the first compartment ( 1 ) to the second compartment ( 2 ),
b) a source of NO-containing gas having from 1 ppm to 5000 ppm in volume of NO in a balance of nitrogen in fluid communication with the nasal cannula assembly ( 10 ), and
c) a source of an oxygen-containing gas containing at least 21% (by volume) of O 2 in fluid communication with the nasal cannula assembly ( 10 ).
2. The breathing assistance apparatus according to claim 1 , wherein the two valve elements ( 3 ) are arranged in the separation wall ( 6 ), directly opposite the pair of nasal prongs ( 5 ).