I'll be honest, I don't really know anything about cats (being a dog person myself
But with 2 enemas, a sedative, and obviously trouble with extreme constipation, I'd be concerned about fluid levels and dehydration. Is your kitty drinking anything?
Perhaps some room temperature chicken broth would be enticing to him?
Best of luck. That sounds like a lot for the little guy to go through. I hope he feels better soon.