This page explains what a contrast extravasation is, how it is treated, and symptoms to watch for. DOWNLOADABLE PDF: Contrast Extravasation.
The amount of fluid a child needs depends on many factors including their age, their gender, the weather and how much physical activity they do, but generally they should aim to drink about 6-8 glasses of fluid per day (on top of the water provided by food in their diet).
This is from the first part of that link Amanda. How much milk should my toddler drink? Your 1- to 2-year-old child should drink 16 to 24 ounces of whole milk a day. While you'll most likely have to work to make sure he meets the requirement, keep in mind that it is possible for him to drink too much milk.