My 4yr old baby girl cannot keep any food down. just after eating she vomits. please help?

Ice chips: Initial efforts should focus on hydration. Some ice chips offered as tolerated can settle the stomach. If she can take an ounce or 2 of clear liquids every few minutes it will help. When she tolerates more you can offer more but too much at one time will result in a stomach spasm/vomit. If she can pee every 6-8 hrs she is hydrated. Less-may need to see a doc.