My son vomited violently and unfortunately much of it came out of his nose. He is now completely stuffed up, he cannot breath or blow out of his nose. We believe that he still has vomit in his sinuses but we are not sure how to get it out. Is this something worth going to the emerge for or wait it out??
It will be gradually expelled along with the usual mucus from the nose and post nasal drainage.
However, if it is really bothering him, there are some things you can try. Depending upon his age, you could try a expectorant. An expectorant helps to break up the congestion to make it easier to cough up or blow out of the nose. You would not want to use a decongestant because that would dry up the mucus, making it thicker and more difficult to expel out of the nose.
You can also try a saline nasal spray which will make the "stuff" more runny, making it easier to expel when blowing the nose. A hot shower or a "mist tent" will do the same thing. A mist tent is just holding a towel over a steaming pot of hot water then breathing in the steam mist. This has to be done with parental supervision.
Usually the above will take care of the problem. Most physicians will take the wait-and-see-what-happens approach, after suggesting the above. It would really be rare for them to try something like a nasal lavage, and your son would probably not like to have that done to him. So, you might try some of the above, if it is really bothering him. But, it will gradually be expelled for the nasal passages with the usual mucosal drainage.