Please Help....Someone with knowledge...what is it....collapsed trachea?

My dog is having trouble. He is coughing out and then he gags. (NOT snorting in) He is not able to sleep any longer than 1/2 hour without coughing and gagging. He is not able to get much sleep because if this. Is this typical of a collapsed trachea? He has all of his vaccinations, including bordetella.