I havent' been to a pulmonologist yet, as the Neuromuscular clinic does PFTs (pulmonary function tests) at the clinic.. They do a FVC (forced vital capacity, i believe is what it stands for).. I like that they do that each appointment, so that I have concrete numbers that I can track... When I feel like I can't breathe, usually they are low.. however my pulse ox remains good..
Im sure an actual pulmonologist would do more tests even - PFT's, and something called a snif test or something - I believe it tests your diaphram strength?
Of course they have swallowing studies - barium swallowing I believe to test that part of it..

Its so anxiety provoking not to be able to breathe, so getting those numbers is really useful I think.. mentally too!