How to perform CPR

The real thing isn’t exactly the Hollywood version, but it’s no less dramatic

On television, cardiopulmonary resuscitation (CPR) is like the Fonz hitting the jukebox on Happy Days: whack a dying person in the right spot and his heart will start beating again. However, this hardly ever works in real life, and it isn’t actually the point of administering CPR. The real goal here is to buy some valuable time until it’s possible to revive a normal heart beat, typically using an electric jolt from a defibrillator.

The cells in your body need oxygen to convert food into usable energy. Your heart delivers the goods. It pumps oxygenated blood from the lungs out to the body, and pumps de-oxygenated blood back to the lungs. If your heart isn’t pumping sufficient blood – a condition called cardiac arrest – your body’s cells will fail. Most significantly, your brain cells (neurons) will start dying four to six minutes after cardiac arrest begins. 

Ten minutes without resuscitation efforts and the chances of revival are almost nil. The basic idea of CPR is to hold off death by manually forcing the victim’s lungs and heart to provide oxygenated blood to the brain. Exhaling air into the victim’s lungs provides the necessary oxygen, and regularly compressing the chest forces the heart to pump blood.

Step by step resuscitation

Authorities differ on exact recommendations. The procedure described here is based on guidelines from the Resuscitation Council (UK). To ensure you administer CPR correctly, it’s essential to take a training course with a qualified instructor. If you believe
someone has suffered cardiac arrest, gently shake their shoulders and shout, “Are you
okay?” If the victim responds, he has not suffered cardiac arrest and does not need CPR. If the victim doesn’t respond, yell for help.

1. Clear the airway

Carefully roll the victim on his back. Gently press his forehead to tilt his head back, while lifting his chin. This will clear the airway. Watch chest movement and listen for normal breathing. If the victim is breathing normally, do not administer CPR. If you aren’t sure whether the victim is breathing normally, assume he is not.

2. Prepare for chest compressions

Before beginning compressions, ask someone to call an ambulance. If you’re alone, call yourself. Kneel beside the victim and place one hand over the other, interlocking your fingers. Place the heel of your lower hand in the centre of the victim’s chest, but not above the ribs.

3. Begin chest compressions

With your arms straight, press down 4-5 cm on the sternum, and then release. Continue compressing and releasing at a rate of a little less than two full compressions every second (a rate of 100 compressions per minute). Oddly enough, timing compressions to the beat of the Bee Gee’s Staying Alive works perfectly.

4. Administer rescue breaths

After 30 compressions, reopen the victim’s airway and pinch his nose closed. Take a breath, place your lips around the victim’s mouth, and blow into the victim’s mouth. Watch for his chest to rise, then remove your mouth, allowing air to escape again. Repeat the process for a second breath, then administer 30 more chest compressions. Continue the cycle until help arrives.


 This article was originally published in How It Works issue 11


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