Reverse Sneeze or collapsing trachea?

Reverse sneezes sound bad ... it sounds like the dog is asphyxiating and panic tends to make it way worse (the dog's or yours).  'sneeze' is totally the wrong word - it's always been my assumption that somehow the epiglottis (that flap of skin the the throat that keeps you from inhaling food) flips shut when it shouldn't or something causes them to not be able to get air easily and the more they suck air the worse it becomes. 

I've done everything from mouth to mouth to just petting them, but someone on here actually recommended to just cupping your hand over the nose/mouth which has the effect that putting a paper bag over someone's mouth who is hyperventilating does -- it calms  it down almost instantly. 

A bent trachea is exactly that -- it happens to some small breeds, particularly bracheocephalic breeds or dogs who have an extremely enlarged heart (and the organs re-arrange themselves and can 'bend' the trachea.)

I've heard vets instantly recommend euthanasia for a bent trachea and that's absurd.  Ms. Socks had an extremely bent trachea for all the 6 1/2 years she lived with us (from age 10 1/2 to 17) -- and it just requires a bit of managing and keeping them calm.  I used to feed her from an elevated dish - it helped her a lot.

They can make noise with a bent trachea and it may even cause reverse sneezing **I don't know**.

 Tootsie "reverse sneezes" frequently. I cup my hand over her mouth and it immediately calms her.

Reverse Sneeze Syndrome or Pharyngeal Gag Reflex
http://www.peteducation.com/article.cfm?cls=0&cat=1276&articleid=1112
http://en.wikipedia.org/wiki/Reverse_sneezing
http://www.veterinarypartner.com/Content.plx?P=A&C=189&A=2335&S=2
http://www.cpvh.com/Articles/45.html
http://www.linusnlucy.com/smallbreeds.html

Reverse sneezing sounds similar to the honking noise made by a dog with a collapsing trachea, but reverse sneezing is a far simpler condition that usually does not need any treatment. It is called reverse sneezing because it sounds a bit like a dog inhaling sneezes. The sound the dog makes can be so scary that many owners have rushed in a panic to emergency clinics in the middle of the night.

The most common cause of reverse sneezing is an irritation of the soft palate and throat that results in a spasm.  During the spasm, the dog’s neck will extend and the chest will expand as the dog tries harder to inhale. The problem is that the trachea has narrowed and it’s hard to get the normal amount of air into the lungs. 

Anything that irritates the throat can cause this spasm and subsequent sneeze. Causes include excitement, eating or drinking, exercise intolerance, pulling on a leash, mites, pollen, foreign bodies caught in the throat, perfumes, viruses, household chemicals, allergies, and post-nasal drip.  

A Corgi had an episode at my last agility trial (the "reverse sneezing" thing) and what did the trick was when someone grabbed a jar of peanut butter and spread some on his nose.  Apparently you want to try to get the dog to lick/stick their tongue out rather far and this fixes the problem.  His owner was blowing into his nose trying to get him to lick, but he was too stressed to respond -- until the peanut butter came out!