Boerhave's Syndrome sounds nasty. My brother almost died last year from a very similar condition called Mallory-Weiss Syndrome. For him is was not that he vomited often, but one night he got sick and wretched badly enough that he actually tore a hole where the esophagus meets the stomach. He went to sleep, woke up the next morning (unaware of the fairly massive internal bleeding that had been going on all night), walked to the bathroom and immediately passed out because he didn't have enough blood left to pump it to his brain. Then he began to vomit all of the blood that he lost because it had been pooling in his stomach overnight. I found him (luckily) in time to call an ambulance and have surgery performed quickly. I think the doctors estimated he lost nearly 30-35% of the blood in his body.
I would imagine that is another condition which bulimics would be faced with. Scary stuff...certainly a morning I'll never forget.