Continuous positive airway supply system to nasal cannula

1. A combination control for use in nasal cannula therapy, comprising

a) a nasal cannula respiratory assistance ducted apparatus,

b) said apparatus including the following ii) proportioning second valve means and at least one of the following i) flow metering first means and iii) flow metering third means:

i) said flow metering first means upstream of the nasal cannula,

ii) said proportioning second valve means also associated with said apparatus ducting, serving as a safety release valve, downstream of the nasal cannula,

iii) said flow metering third means associated with the apparatus ducting, and downstream of the nasal cannula.

2. The combination of claim 1 includes, in series sequence

i)′ an oxygen gas source,

ii)′ means receiving oxygen from said source, and air, for blending air and oxygen and/or nitric oxide in an output stream,

iii)′ a heater/humidifier to heat and humidify said stream,

iv)′ said nasal cannula to receive the heated and humidified stream,

v)′ said i), ii) and iii) means, as defined.

3. The combination of claim 1 wherein said nasal cannula comprises a by-pass outlet from the apparatus ducting for air and oxygen flow to the patient's nose, downstream of said first means.

4. The combination of claim 2 wherein said nasal cannula comprises a by-pass outlet from the apparatus ducting for air and oxygen flow to the patient's nose, downstream of said first means.

5. The combination of claim 3 wherein said ii) means comprises a proportioning valve positioned for discharging excessive-pressure air and oxygen blend from said ducting.

6. The combination of claim 4 wherein said ii) means is positioned for discharging excessive-pressure air and oxygen blend from said ducting.

7. The combination of claim 3 wherein said ducting includes plastic tubing forming a loop, said bypass outlets projects from the loop, and a holder clasping two portions of the tubing to form the loop.

8. The combination of claim 1 wherein said included flow metering first means or flow metering third means comprises a flow metering element in ducting hem apparatus.

9. The combination of claim 1 wherein said included flow metering first means and flow metering third means comprises flow metering elements in spaced apart sections of the ducting.

10. The combination of claim 1 wherein said flow metering first means is located upstream of said proportioning second valve means.