Mom has started blowing out air through her lips. It gets quite loud, and it's mostly constant. Anyone else experiencing this?

Mum did the blowing. She had COPD and the blowing made her even more breathless, but it was difficult to get her to stop and calm her breathing down. The more she blew, the more agitated she became.
Sometimes, I could calm her breathing by getting her to breathe with me, and I would do slow deep breaths. Then, when she fell asleep, she would breathe more normally.

If she is basically healthy, it is a habit. If she has heart or lung issues, get it checked out.

I knew someone who did that, and it turned out to be sleep apnea.

mamac610: A psychiatrist could address this tic.

Does yout mom have any heart issues? My mom made those sounds because of her heart issues the last few.months she was alive.

My mom did this blowing air out of her mouth thing. She was a former smoker and I suspect she was just replaying this old behavior but who knows.

They can start to do various repetitive things, picking is one my mom also would do. Perhaps it is some type if “self soothing” thing.

best to just ignore it if it is not dangerous.

My mom 82, does something similar. Her sound is like yawning. It gets quite loud. And irritating. It is caused by dehydration. She does not drink enough. I am learning to live with it.

These are very common "tics" that can occur. Some are medication induced and called tardive dyskinesia, but others may just occur in aging brain functioning. They vary from the blowing to just a lot of mouth movement, and sometimes putting in and out of the tongue or chewing when there is nothing to chew. This isn't unusual. You might start with looking up "facial tics in the aging". There is a tremendous variety. I am assuming this person is having normal O2 saturations, respiratory rate. This is worth discussing with a call to MD.