I spoke with our vet about when the fluids slows down. I told her I use the same technique that I did with IV's, wiggle the needle, it can be positional. I have never withdrawn the needle, put on a new needle, and reinserted it. The cat would not stand for that!!! Sometimes, if you just pull the needle back a teeny tiny bit, it helps getting the fluids flowing again...I have also fed a cat while giving it sub q. Spunky was IMPOSSIBLE, so I would cut up some cheese and mix it into baby food. While he was gobbling away, I could insert the needle, and get him hydrated. As you can see in the photo of Boo and Nicholas, despite Boo sitting up, the fluid still went in!!!