One thing to add, that haven't been thought to me in the CPR course.

It's fucking exhausting and you will get tired very soon. The training dummy doesn't require nowhere near as much force as a real person. To give you an example, it's quite common to crack or break a rib of the CPR recipient even if CPR is done right. That's how much force you have to use. Without the required force, your pushes won't reach the heart.

Make sure there is someone else who knows how to do CPR or at least is looking how you're doing it and can repeat that or follow your commands once you switch.

I've only had to give someone CPR once and I haven't been as tired in my whole life. No way the "I've been giving him CPR for 30 minutes..." You see on a TV screen is real. I felt like I'll need CPR myself after 3 minutes.

For those curious about what a defibrillator does do: It stops hearts.

Which might seem insanely counterintuitive, but it's great for when the heart gets stuck in a rhythm that prevents it from being able to pump properly, since stopping it lets it restart itself in a more normal rhythm.

Before we invented the defibrillator, doctors basically had to punch the patient in the chest to hopefully hit the heart at the right point to stop it. It does also mean that if you really know what you're doing, and got lucky with the timing/amount of force, you could technically pull off one of Kill Bill's death punches, although it would be a little less dramatic than them walking five steps before their heart explodes.

But unlike video games, unless you fry the heart itself, a defibrillator won't instantly kill someone. It will stop their heart, sure, but their heart will restart itself, unless something is wrong (stopped for too long, physical damage, irreversible chemical imbalance, etc)

Ah, ha, ha, ha, stayin' alive, stayin' alive

The other thing they don’t say during cpr class is that the resuscitation rate for an out of hospital cardiac arrest is 9.1%.

One of the biggest factors in survivability is the time to initiate CPR in the time the compressions are interrupted. My EMS department has moved away from a AHA to high performance CPR. 

It's like we're redoing the basics of reddit. :)

We do not use 10 percent of our brains.

(This is jest, not complaining)

I'd say this information will come as a shock to many but apparently it won't!

It's concerning how there is no AED/CPR training in school considering everyone is likely to run into a situation where a family member will need resuscitation while waiting for an ambulance. Not knowing when and how to do cpr, how to use a defibrillator (portable ones give audio instructions) etc is so dangerous because by the time an ambulance gets there it may be too late. Also I wish AED were more readily available and easily located. May even be a good idea to pitch in with neighbors and make a locked box that's easily accessible.

I've heard this before and looked it up, but I found this article from the NIH that contradicts what you're saying.

Defibrillators are devices that send an electric pulse or shock to the heart to restore a normal heartbeat. They are used to prevent or correct an arrhythmia, an uneven heartbeat that is too slow or too fast. If the heart suddenly stops, defibrillators can also help it beat again.

Not a doctor but I think AEDs can only fix an arhythmic pulse as is the case when ventricular fibrillation occurs.