Then how does that explain having the IMDB rating of about 6?
I'd suspect that'd have to do with its obscurity. Only fans of the movie would care enough to go to its IMDB page.
Clayton starts to cry on the operating table, then starts yelling for the anesthesiologist to notice. Why? What's it going to help at this point? He doesn't seem to be in pain anymore, and the heart's out, so they presumably can't stop the surgery and wake him up. Perhaps he'd be able to actually make him sleep, but that'd still yield the same result as him being awake.
Probably so they can re-administer the anesthetic and get him back to sleep. Heart surgery takes a lot longer than 2 hours, and being sewn back up would probably be pretty painful, too.
But he still gets killed, whether he's actually a sleep or not. He's yelling with a distinct desperate tone to his voice like it'll matter. Does he just not want to see it happen?