There's Tuna in the Phone! Go Get It!

Someone's cat apparently dialed 911 after he (the person) fell out of his wheelchair. I've heard of this happening before, but what gets me is the guy actually tried to train the cat to dial 911, never really sure if the training took. Now, I know how to (in theory) train a cat to use a toilet, which is a fairly complex and unnatural task, particularly if you include the act of flushing when done (it helps if they enjoy watching the water swirl in the toilet - it gives them the extra motivation to learn that last part, which one of my cats did on his own). But what's the procedure for teaching a cat to dial 911, especially if you only want him to do it in an emergency? It's not exactly something that you would want your cat doing every time he wanted a treat. To make it simpler, you put 911 on speed dial. But after that? Do you lie on the floor and then put a bit of tuna on the appropriate button (with the phone unplugged)? Or do you teach the cat to respond to the command "call 911"? The command part probably wouldn't be helpful if you were unconscious. So, so long as you never randomly lie down on your floor, you could probably go for the first option.