As most of us know, CPR is an emergency response to someone who has stopped breathing or who has had their heart stop pumping blood.
The principle behind it is to mimic the natural movement of the heart and lungs thus artificially introducing oxygen and blood flow to a person until either they revive or help arrives.
Knowing when to initiate CPR can be tricky; merely because someone is unconscious is not a reason to perform it – initiating it when it is not necessary can actually harm a person rather than help them.
They have to be showing no evidence of consciousness and also not have vital signs that would prove they are in a bad state but breathing with a functioning heart.
On the next page, we cover the basics of CPR, including how to check whether a person truly needs it.