If you take a look at one of the references at the end of my post they mention a weak solution of Hydrogen Peroxide for the nobe (as my husband calls it). I wonder if that would help for your sinuses.
Must be a weak solution...look at the reference. I did try it with a stronger solution (before I read the reference) and it did flush but was a nasal adventure that is probably best not repeated. But I think the weaker solution may be beneficial.