I just had mt breathing test to get a POC. He put me on pulse, and we walked with the tank. Well, half way back he said you are not breathing through your nose. And I said, yeah, I was.And he knew I was. He switched the cannula that the company sent with the ones I bought (see below), and voila! The company one works when it feels like it, even when new. The cannula I bought worked perfectly every time. My numbers went UP, and I qualify for the smaller POC unit -- hooray. Of course it will take months to get here...sadly.
I bought the new cannulas based on information from this QA board which someone has posted -- Salter's 16SOFT Nasal Cannulas . From Direct home Medical. Linlk Below. Made all the difference in the test (and I breath better with them). So, thanks to whomever posted that, and may we all learn from this experience.
http://www.directhomemedical.com/