A couple of points from what we've seen to date:
- The original sleep study showed up mainly central apnea. Whether that is endogenous or caused by her medication is to some extent immaterial. An ordinary CPAP or APAP will not satisfactorily treat central apnea.
- The central apnea is continuing while under treatment.
- The maximum pressure is not set high enough to treat the obstructive apneas, especially the cluster which seems to happen every morning (which I still think might be positional).
- The latest chart showed a significant amount of periodic breathing, which may not be significant, but does need to be looked at by somebody who knows.
The mouth-breathing is not an issue as far as I can see. It normally shows up as a very distinct leak pattern, which is not present in her charts.
CRS is a big company with a lot of branches. In such a situation it's always possible to get a one-off incompetent person. When I used them (about four years ago) I had a brilliant therapist and a couple of average ones. I think you've copped a dud. It's also the case that they see dozens of ordinary obstructive apnea patients for every one central, so often they are out of their depth in a serious case like your mother's.