short of breath & energy zapped?

Hi,
I do a support group for kids with IBD. 5 kids ages 8-13 all describe the following "yuckie feeling"-and our docs can't say exactly what it is that is happening? Starts with shortness of breath/"no air to talk", then stomach "squeezing in" & "crampy", "you like loose your energy-like you're going to pass out" and feels "like the throw up is coming up". All this happens at the same time.
They want to know what is happening inside their bodies. Anyone have this yuckie feeling?
Any clue as to the cause?.
Carol - GI social worker.