o2 in cpap

[greatunclebill]

ok, if she don't jump i think we've got 'er. the corn-fusing part which i now understand was how the seemingly little trickle of air you feel from a cannula could go out of the hose and push into the semmingly greater pressure from the machine. the low flow of the o2 is actually at a greater pressure than the higher flow of the cpap air.

with both of us on cpap and my wife needing o2 at night, the generator vs backup battery is looking more like generator to me. actually evacuation is starting to come into the equation.

thank you, guys.

[JumpStart]

Though I doubt there would be any harm in o2 entering the device, I suppose there could be an increased fire risk given that o2 promotes combustion. In any case the point should be moot since the flow rate of the o2 is so very much lower than that from the pap. Keep in mind that the flow rate for the o2 is only 2 or 3 liters per minute, I have no idea what the typical flow rate is for a cpap, but my Sleepyhead reports commonly show leaks over 25 lpm, so actual output has to be a number greater than that.

The o2 pressure is several hundred times greater than that of the air from the device, so it has no trouble at all being introduced into the stream, but the flow rate is proportionally miniscule compared to the flow from the pap, ensuring the delivery to the patient rather than backflowing to the machine.

Don't know if it is required for xPAP usage with O2, but a google search revealed the following picture of a backflow preventer:



with the following description:

The Pressure Valve is designed for single patient use on all Respironics BiPAP and CPAP machines. It is a spring-loaded valve tht helps prevent the backflow of oxygen or water from the patient circuit in to the BiPAP or CPAP machine when the CPAP machine is turned off. Any backflow passes out of the circuit through the vents. When the CPAP machine is operating, the valve allows air to flow through the patient circuit. The vents are sealed to prevent flow out of the circuit.

The inlet side of the valve is a 22 mm connector that fits on the outlet port of the BiPAP or CPAP machine. The outlet side of the valve fits a 22 mm connector on a bacteria filter or smooth inner lumen tubing. The minimum operating pressure is 2 cm H2O.

At least somebody besides me thinks a backflow preventer might be useful.

[Sleepster]

At least somebody besides me thinks a backflow preventer might be useful.

If you scroll up to Zonk's post in this thread, you see that Respironics mandates the backflow preventer. It's a safety feature, and under normal operating conditions serves no function.

Of course, the danger is when something abnormal occurs. Like a leak of oxygen into a small enclosed room followed by a spark from a frayed electric cord that's been chewed on by your dog.

[JumpStart]

At least somebody besides me thinks a backflow preventer might be useful.

If you scroll up to Zonk's post in this thread, you see that Respironics mandates the backflow preventer. It's a safety feature, and under normal operating conditions serves no function.

Of course, the danger is when something abnormal occurs. Like a leak of oxygen into a small enclosed room followed by a spark from a frayed electric cord that's been chewed on by your dog.

Sorta like seat belts or air bags in a car? An abnormal event like a spark from the cpap blower motor starting? All in all, pretty useful to have around I would think. :grin:

[TorontoCPAPguy]

Sorry for the late post on this but I felt it important. I use O2 infused into my CPAP airline. Halfway down the air hose is the adapter you first mention; it is simply a coupler for the two hoses and has a nipple on it that the airline fits onto from your oxygen supply (I use a concentrator); the oxygen is essentially sucked into the airflow and mixes.

It is also very important to turn your O2 supply on and off with your CPAP. But, before even thinking about all of this, you need to thing about installing the second pictured item above at the output of the CPAP machine. It is a backflow valve and prevents the oxygen from flowing back into the CPAP machine and creating a fire hazard. It will open when the CPAP is running and air is flowing out of it.... and it will immediately shut should the CPAP airflow cease, preventing any backflow. It has slots all around to vent the excess oxygen into the room air.

I have an O2 'meter' that measures the percentage of oxygen in the air it is exposed to. I find that at 4L/M of oxygen flow from the concentrator, it raises the normal atmospheric oxygen level of 21% up to about 35% or so and makes all the difference in the world to me in terms of REM sleep.

Hope that this explains things.... and more so than just answering your question, it is ESSENTIAL that you install that backflow valve right at the output of your XPAP machine so that oxygen does not flow back into the machine and pool, creating a fire hazard. The valves are cheap and you need to make sure that it opens when you turn the XPAP on with a crisp 'click' and that it closes (observe visually) when the XPAP is turned off, also with a crisp "click".... you should have a spare or two on hand as it is absolutely essential if you are infusing oxygen!

Again, sorry for the late post on this... just happened to trip across it and had to speak up.

Uncle Bill?

[TorontoCPAPguy]

At least somebody besides me thinks a backflow preventer might be useful.

If you scroll up to Zonk's post in this thread, you see that Respironics mandates the backflow preventer. It's a safety feature, and under normal operating conditions serves no function.

Of course, the danger is when something abnormal occurs. Like a leak of oxygen into a small enclosed room followed by a spark from a frayed electric cord that's been chewed on by your dog.

The backflow valve is essential as if you turn your XPAP off prior to turning your oxygen off, it WILL backflow to some extent into your XPAP. It is only a minor hazard, but a spark generated when turning the XPAP back on can be a fire hazard, so you are right, it is generally a hazard only when something unusual happens.... but even a power failure can be adjudged an unusual event or anomoly if you are using tanked oxygen or if your concentrator continues to pump out oxygen for a few seconds after the power turns off.