That's the problem: They can't tell you what's wrong, so you have to make an intelligent guess based on how well you know your pet. What's your pet's basic heartbeat, for starters? What's their body temperature when they are healthy? You have to measure that rectally <img src="/images/graemlins/tongue.gif" alt="" /> . How many breaths per minute does he or she take at rest and during play? That kind of thing.
Here's the link for the specific course I took. It will tell you basically what is involved:
Pet First Aid Course DetailsHere's a link to the Pet First Aid course as described by the American Red Cross:
Pet First Aid This is what got me started searching for a local course.
I hope this helps somewhat.
-- Craig