Have you taken his temp at home when he's having an episode, Angelyc? Pale gums often indicate anemia. It almost sounds like his circulation is being impaired temporarily. Very scary.
I'm just paranoid enough that if it were my dog, I'd ask for a referal to a Veterinary Teaching Hospital to have him checked out by a specialist. It's pricey, but the few times we've had to drive over to the Cities to the VTH we got the answers we needed...
Hope you get some of those answers soon!
