I'm not a medical person, but my guess is no.
I'm assuming you mean he uses the oxygen during sleep, not during the day?
Now, there's a chance some of the oxygen may seep through so it's better than nothing, but as long as there is still obstructive sleep apnea happening and he's untreated, then he will still stop breathing in his sleep.
Do you know more about his condition. Had he gotten a copy of the report following his sleep study? It's important to know if his apnea was mild, moderate or severe, based on AHI (apneas and hypopneas per hour) determined by his sleep study. That would tell you if there are alternatives available to him.
But it's interesting that he tried to make the Activa into a full face mask (pretty creative!). He is right in that if you are mouth breathing but using a nose-only mask, then the pressure can't work as it should to keep his airways open as he sleeps. My analogy is a tire ... you can add air to pressurize the tire, but it won't work if you don't fix the leak.
There are other masks. There is even a new type of full face mask, the Hybrid and the Resmed Liberty, which cover the mouth but use nasal pillows instead of covering the nose. Plus I believe that the Resmed Quatro is their full face mask version of the Activa, and people seem to like that.
Can you tell us his reasons for quitting? The reasons can vary. It could be frustrations over the mask, or over how he breathes with it, the pressure (what is his prescribed pressure?), or it could just be more of an attitude thinng. Let us know more, maybe we can suggest more.
Linda
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