I was told that my mother who is in the final stages of Alzheimer's had to have a pike put in. What is that?

I just watched my FIL go 12 days with no food or drink before he finally died, in the last stage of Alz. The body shuts down, there is no mouthing or swallowing anymore. You can prolong their "life" with nutrients through a feeding tube, but really you're just feeding an existence, not a life. Are you sure that's what Mom wants? Usually they either drown in their lung fluid/pneumonia or dehydrate. Neither is pretty; it's a very tough call. Best wishes to you.