There are ten schools, most in states that allow AAs to practice. The most recent school is quinnipac, with the previous one accredited in 2012. I wouldn't say it's catching fire, but it is a good option if one is fine with the practice and geographic limitations to the 16 states (as well as all VA facilities and some US territories) that allow for AAs. That's not a minor issue considering the expense of such a program. With CRNA saturation and voice, I was worried about AA becoming a niche career field. The CRNA clearly sees AA as a direct threat, and aren't sitting back to let AAs gain ground that they cleared. I'm also uncomfortable with having it be a job that has no rights to practice in the majority of the country. But becoming a CRNA would take a non nurse several more years, so you might as well even become an MD gas passer rather than CRNA. AA programs have similar prereqs to MD school, so you could even go that route vs AA.
It's a cool concept, at least if AAs had hce requirements that students have been RTs for a few years like the ones CRNAs schools have for critical care nursing experience. RT background is powerful hce.