If you have ever taken a CPR class but you haven't taken one for several years, you need to sign up again. The procedures for CPR have changed so much over the past few years that if you tried to do CPR now the way you were taught then, you'd be violating most of the requirements. Some of the core processes in CPR have gone from being the most important to not-so-important, and vice versa.
Compressions Instead of Breaths
This was the big change that made people sit up and look. Originally, you were supposed to clear the person's airway, give them some rescue breaths, start chest compressions, and then alternate the breaths and compressions. Now, those breaths aren't considered so important. They haven't been totally eliminated because some people do need them, but you need to concentrate on the compressions instead in most cases.
This news was greeted with mixed reactions. People who were worried about diseases—and for good reason—were relieved because they wouldn't have to deal with putting their mouth on a stranger's face. People who were dedicated to using rescue breaths, of course, weren't so happy.
However, the research was on the compression side. VeryWell.com noted that the research leading to the change found that compression-only CPR resulted in better survival rates.
Compression First, Forcefully
In addition to concentrating on compressions instead of breaths, you're now also supposed to do compressions first instead of checking the airway. The compressions keep blood flowing to the brain—this is the core purpose of CPR. Checking the airway and doing rescue breaths just delayed the start of the compressions, which wasn't helping most people. You also have to make the compressions stronger.
Another change is that now you're supposed to keep trying. There's no real stopping point for CPR anymore, other than paramedics arriving and taking over from you. Stopping CPR before then is risky simply because you are not trained to see what's happening in the person's brain and cardiovascular system, and you risk stopping too early if you try to judge whether the CPR is doing any good. So, now, you need to do CPR for as long as you can, rather than for as long as you think is necessary for the person.
It's easy to get recertified in CPR; all you have to do is take another class. Contact CPR and first aid schools, as well as hospitals, for information on when another CPR class might be held. For more information, contact associations like American Heart Association - AED $40 CPR LLC - Certification Training Classes.