Hands-only CPR
When someone is unresponsive and not breathing normally, push hard and fast in the centre of the chest, 100 to 120 times a minute, until help or an AED arrives.
Heart attack is not cardiac arrest
Heart attack
A blocked artery starves part of the heart muscle of blood. The person is usually awake, often with chest pain or pressure, and they are breathing. Call the emergency number and keep them resting. They don't need CPR, but a heart attack can turn into a cardiac arrest, so stay with them.
Cardiac arrest
The heart stops pumping effectively. The person collapses, is unresponsive and not breathing normally. Without blood flow the brain is damaged within minutes. Call and start CPR now.
WHY IT WORKS
Your hands do the heart's job for a while
Pressing down on the chest squeezes the heart between the breastbone and the spine and pushes blood out to the body; letting go lets it refill. It moves only part of the usual blood flow, but it keeps some oxygen reaching the brain until an AED or paramedics arrive. Bystander CPR is widely reported to roughly double or triple someone's chance of surviving a cardiac arrest (the exact figure varies from study to study).
CPR rarely restarts a heart on its own. Its job is to buy time for the thing that can: an AED shock or professional care (lesson 05).
Check yourself
At a family lunch, Kian's father says he has a crushing pain in his chest. He is sweaty but awake, talking and breathing. What should Kian do?
- Start chest compressions straight away
- Call 115, keep his father resting, and stay with him in case he collapses
- Drive him to hospital himself without calling
- Tell him to walk around to ease the pain
Show the answer
Call 115, keep his father resting, and stay with him in case he collapses
Right. Awake and breathing with chest pain sounds like a possible heart attack: an emergency, but not one for CPR. Call, keep him resting, and stay close. If he collapses and stops breathing normally, then CPR.
Getting into position
- On a firm surface
They should be on their back on the floor or the ground. A bed or sofa sinks under your hands and swallows the push, so get them onto the floor if you can.
- Kneel beside the chest
Close to their side, your knees near their shoulder and chest.
- Heel of one hand in the centre of the chest
On the lower half of the breastbone, in the middle of the chest. Put your other hand on top and interlock your fingers, keeping them lifted off the ribs.
- Arms straight, shoulders over your hands
Lock your elbows and push down with your body weight, from your hips, not with your arm muscles. That's what lets you keep going for minutes.
THE NUMBERS
Hard: 5-6 cm. Fast: 100-120 a minute.
For an adult, push the chest down 5 to 6 cm (about 2 to 2.4 inches), at a rate of 100 to 120 pushes a minute, which is about two every second. After each push, let the chest rise all the way back up, without leaning on it, so the heart can refill. Keep pauses as short as possible: when your hands stop, the blood flow stops too.
Many courses use songs with the right beat as a tempo guide, such as "Stayin' Alive" by the Bee Gees. Push on the beat.
Check yourself
How deep should each chest compression be for an adult?
- About 1 to 2 cm, so you don't hurt them
- 5 to 6 cm
- 10 cm or more
- As deep as the chest will go
Show the answer
5 to 6 cm
Yes, 5 to 6 cm for an adult. That's deeper than most people expect, which is why too shallow is the most common mistake.
Rate: 100 to 120 pushes a minute.
100 per minute = 100 / 60 = about 1.7 a second
120 per minute = 120 / 60 = 2 a second
How long do 30 pushes take?
at 120 a minute: 30 / 2 = 15 seconds
at 100 a minute: 30 / 1.7 = about 18 secondsTarget: about two pushes every second.
30 pushes should take roughly 15 to 18 seconds.Count out loud: "one, two, three...". Counting keeps your rhythm steady and tells anyone helping you how far you've got. Under stress people tend to drift, so check against a song or a phone metronome if you can.
Check yourself
Which rate should you aim for when giving chest compressions?
- About 60 a minute, one a second
- 100 to 120 a minute
- 150 to 180 a minute
- As fast as you possibly can
Show the answer
100 to 120 a minute
Right: 100 to 120 a minute, about two every second, letting the chest rise fully between pushes.
Hands-only CPR
Cardiopulmonary resuscitation with chest compressions only, no rescue breaths. It's what untrained rescuers, or anyone unwilling to give mouth-to-mouth, should do, and it's far better than doing nothing. Rescuers who are trained and willing can instead give cycles of 30 compressions and 2 rescue breaths (30:2).
You don't need to put your mouth on a stranger to save them. Pushing hard and fast is the part that matters most.
Check yourself
If you haven't been trained in rescue breaths, giving chest compressions alone is still worth doing.
Show the answer
True
True. Hands-only CPR is exactly what untrained rescuers are taught to do, and it's far better than nothing. Push hard and fast until help or an AED arrives.
Keep going, and when to stop
- CPR is exhausting. If someone else can help, swap about every 2 minutes, with as short a pause as possible.
- Keep going until professionals take over, an AED tells you to pause, the person clearly starts to wake up (moves, opens their eyes and breathes normally), or you're physically too exhausted to go on.
- Ribs may crack. It's a known side effect, not a reason to stop: someone in cardiac arrest can't be made worse by your trying.
- Common mistakes: too shallow, too slow, leaning on the chest between pushes, stopping to check too often, CPR on a soft bed.
Check yourself
Reza has been giving CPR to a man at a football pitch for six minutes. Which of these is a reason to stop?
- He heard a crack from the man's ribs
- The man took one gasp
- Paramedics arrive and take over
- Two minutes have passed with no change
Show the answer
Paramedics arrive and take over
Yes. Professionals taking over is one of the reasons to stop. The others: an AED tells you to pause, the person clearly wakes up and breathes normally, or you're too exhausted to continue.
Lesson recap
- Cardiac arrest: collapsed, unresponsive, not breathing normally. A heart attack is different: usually awake with chest pain. Call for both; CPR is for the arrest.
- Call on speaker, send for an AED, and start: heel of the hand in the centre of the chest, other hand on top, arms straight, on a firm surface.
- Push 5 to 6 cm deep, 100 to 120 times a minute, letting the chest rise fully each time, with as few pauses as possible.
- Hands-only is right for untrained rescuers; trained and willing rescuers can give 30:2. Swap about every 2 minutes.
- Keep going until help takes over, an AED says to pause, the person clearly wakes and breathes normally, or you can't go on. Any CPR beats none.