There is one common condition that may be seen as "hyperventilation," and can be scary to witness. It is called a reverse sneeze.
A reverse sneeze is a respiratory spasm that produces a "goose honk" sound. It can be seen with excitement, tugging on a leash, sudden temperature change (eg going from warm house to frigid outdoors), allergies/post nasal drip and so on. Sometimes a cause cannot be found.
Taking a short video of your dog when he is hyperventilating is a valuable tool for your veterinarian in the office, since the breathing pattern may not be exhibited during the exam. Your vet will check out the heart, lungs and overall health to rule out other medical problems.
Treatment is usually not needed for this condition, but if a cause can be determined, eliminating it will usually solve the problem. For example, dogs that have a sensitive trachea, a harness (versus a collar) may help, keeping the dog calm etc.
More info on this:
- What is a "reverse sneeze"?
- Here is a video where you can see and hear the breathing pattern and "goose honk" sound of a reverse sneeze from NC State University
As always, if your pet is not eating, not acting "normal," or shows changes in appetite, urination or other signs of illness please see your veterinarian as soon as possible.