For me the specific question remains unanswered. There are a lot of results about the health effects on respiration, but none about specifically after a sinus surgery. Might be a question so specific that the internet at large has no answer to it.

What I do not get (on Google, search from Germany) is what you describe, my results are all relevant on the first 3 pages barring 2 results about the surgery instead of the fireplace.