Your question: I am a nurse. We had a patient the other day who was a mouth breather. His sats were in the mid 80s when the cannula was in his nose, but in his mouth they went up to the mid 90s. Is it okay to do this?
My humble answer: Technically speaking, I'd try to increase the flow of oxygen prior to placing the cannula in a patient's mouth. Ideally, the oxygen will collect in the patient's nasal sinuses, which act as a reservoir for this oxygen. Regardless of whether a patient inhales through his nose or mouth, he will inhale this oxygen. So it really shouldn't matter whether a patient is a nose or mouth breather. Plus, the idea of placing a dirty nasal cannula in someone's mouth, to me, seems disgusting.
However, I have seen it work. And, so long as it keeps your patient happy, and his sats are at least in the 90 range, I'd be satisfied with whatever you had to do to satisfy both of these objectives. Thanks for the question.
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