Yeah in Season 11 of episode 24, Richard Weber face his okay to do a new procedure on a minor patient who's parents still haven't answered communication calls. And yeah the procedure has only been successfully been completed on pigs and not yet humans.
But if we want that procedure to be tested and successfully on humans, we gotta try on someone.
And Dr. Hunt didn't make the ethical decision for the parents of the minor patient hasn't arrived and who knows when they'll arrive, if they do, but since his parents aren't responding or at the hospital, they have every right to.