The new rule said that no mouth-to-mouth required in new CPR rules (Sorry Guys!).
Just press on the chest of adult victims untill help arrives.
Maybe this change is in response to people not wanting to practice mouth-to-mouth on strangers. But I think if it is an emergency, why not?
This change does not apply in the case of drowning or suffocation. This only applies to someone who suddenly collapses and is non responsive. This does not reverse the problem, it is a bridge to further treatment.