I Experience Every Time I Vomit I Get Lightheaded And

I experience every time I vomit I get lightheaded and pass out and don't know where I am once I wake up
I have done this ever since I was a child.
I was rushed to the hospital because my husband said I stopped breathing and was still vomiting. The hospital thought it was vertigo. They did run a MRI, CT to make sure it was not a stroke. My doctor has suggested I contact a neurologist. Any ideas what this could be?