I would have used BREATHS only with no chest compressions. I would be afraid of poking a broken rib through the lungs. There may well have been a “sucking chest wound” as others stated before me.
I would have either had someone else try to cover the chest wound as I gave breaths, or would have tried to do so myself.
YES, I have given full CPR twice, with no equipment, by myself. You toss out the “textbook” in trauma cases, each case is different.
Laymen don’t do breaths anymore. You do compression and wait for the EMT’s.
I would not have done breaths.
Some obvious thug on the ground and you have no idea what diseases and other such buggy-boos are in his mouth/system.
Yuck.