Your vet will be able to tell you, but it almost sounds like "reverse sneezing". My doxie Max does it. It looks pretty distressing.

If that's what it is, my vet told me to get next to him and gently stroke his throat and talk to him until he can get it under control. Max may have one a day for a while and then he won't have another for a long time. Doesn't seem to be any reason that I can find to cause them.

Let us know what you find out.