I've given first aid twice in serious car accidents. One when a car got broadsided on Easter Sunday about 6 cars up ahead of me. Anther time when a car left the road and night and stuck a tree (both guys in the car injured.) And once in a karate tournament gave first aid to one competitor who got knocked out (thanking my stars it was not ME that got it!) So with the learning curve my first aid kit in the car got bigger and bigger!
I also taught Texas P&W hunter safety courses. They would send me a list of investigated accidents related to hunting every year. Quite a few would rest their guns muzzle on their foot and play with the triggers (with obvious results.) .22s were not so bad but a few fired shotguns through their feet.
And my learning curve went up some more and the first aid kit got even bigger.
What to do if a AD/ND on the range and someone ventilated?
Well I figured out to keep quick clot bandages in my car's first aid kit. Got both civilian QC bandages and Israeli BDs with quick clot in them. Add regular bandages, tourniquets, some disinfectant, and of course cell phone. Did this so when I went to training classes I aways had the means to give first aid to gunshot victims while getting the ERT to come.
So far never had to us them, and that's ok with me.
"The government has confiscated all of our rights and is selling them back to us in the form of permits."