If the dog is still attached to the flea collar, remove it from the dog. As these flea collars are usually fairly inexpensive, I would recommend cutting it so that it can be removed and puchasing a new one.
And your dog did that how? Cut the collar off with a pair of scissors. Replace the collar with a topical flea/tick solution, like Topline or other over the counter brand....... or replace the heating vent...
Hopefully it is not still on the dog when this happens. I would try to cut it up into pieces to get it all out. Try spot on treatments or pills instead.
