Originally Posted by DJ's left nut
Sounds a little like gastric torsion (stomach flipping over). Large chest cavity?
My understanding with obstructions is that most dogs won't even try to drink with an obstruction, whereas with torsion you'll get the drinking and vomiting; just can't keep anything down.
Sorry about your loss. I hope whatever you find out helps.
that's what one of my friends in vet school was thinking