A person needs CPR when he or she either stops breathing or looks like he or she is ‘knocked out’ and struggling to breath. You can find out if a person has stopped breathing by tilting the victim’s head back and putting your ear to his mouth to listen for breathing. Likewise, a grey complexion and a lack of movement may be also be a sign that CPR is needed.

CPR might be necessary in different emergencies. Here are some of the most common ones:

1. Near-drowning—when lungs fill with water, they need to be cleared out and replaced with oxygen! 
2. Suffocation—perhaps a child was playing with a plastic bag and was unable to breathe.
3. Toxic fumes—will lessen the amount of oxygen in the lungs.
4. Smoke inhalation—will lessen the amount of oxygen in the lungs.
5. Car accidents—someone may go into shock and need their heart pumped.
6. Electrical shocks—electrical shocks can cause a person’s heart to stop beating.
7. Allergic Reactions—can close the airways to the lungs and cause the heart to stop beating.
8. Heart attack—during a heart attack, the person’s heart may or may not stop, but don’t waste time… begin chest compressions.

In the first four examples, mouth to mouth would benefit the victim because lungs have been deprived of oxygen. In the last four examples, chest compressions are sufficient.

Compressions are necessary when a person’s heart has stopped beating—compressions help pump the blood through the body, which is the job of the heart, so when it’s not working, compressions can do the job temporarily until a medic comes along with a defibrillator to electrically start the heart again. A defibrillator is a machine that creates electric shock that can actually restart a person’s heart. You are unlikely to restart a heart with chest compressions BUT you are greatly increasing the chances of survival when the defibrillator is administered.

Mouth-to-mouth is needed when the person may not have sufficient oxygen in his/her lungs. For instance, if a person has inhaled toxic, oxygen-depriving smoke and has stopped breathing, she would benefit from mouth-to-mouth. The smoke in the person’s lungs needs to be replaced with oxygen so that when you then give compressions, the blood can deliver oxygen and not smoke!