3.2 — Cardiac Arrest and CPR

Read this once and you become the most useful person in most rooms.

Cardiac arrest outside hospital is survivable, and the largest single factor in whether somebody survives is whether a bystander started compressions before the ambulance arrived.

**Bystander CPR can roughly double or triple the chance of survival. And in most places, most people who arrest in front of somebody do not receive it — usually because the bystander was not sure, or was afraid of doing it wrong.

You cannot make a person in cardiac arrest worse. They are, clinically, already dead. Anything you do is upward.

What it is

**Cardiac arrest: the heart stops pumping effectively. The person collapses, becomes unresponsive, and stops breathing normally within seconds.

Not the same as a heart attack (3.3), which is a blocked artery and in which the person is usually awake and in pain — though a heart attack can cause an arrest.

Without circulation, brain damage begins within minutes. Which is why the bystander matters more than the ambulance: the ambulance is usually several minutes away and the clock started before you noticed.

The sequence

1. Check safety, then check the person

Shout and shake the shoulders. Can you hear me?

2. Check breathing for ten seconds

Head tilted back, chin lifted. Look at the chest, listen, feel.

And from 3.1: gasping, snoring or occasional groaning is not breathing. This is agonal breathing, it happens in a large proportion of arrests, and mistaking it for breathing is the single commonest reason bystanders do not start.

Not responding and not breathing normally = start compressions.

If you are unsure, start. The cost of compressions on somebody who did not need them is a bruised chest. The cost of not starting on somebody who did is everything.

3. Call, on speaker

112 or 108. Say: cardiac arrest, not breathing, and the location.

Ask whether there is a defibrillator nearby. The dispatcher will coach you. Leave the phone on speaker on the floor.

And if somebody else is there, send them for a defibrillator while you compress. Never leave the person to look for one yourself if you are alone — compressions matter more.

4. Compress

Position: person flat on their back, on a firm surface — the floor, not a bed.

Kneel beside their chest.

Hands: heel of one hand in the centre of the chest, on the lower half of the breastbone. **Other hand on top, fingers interlocked. Fingers lifted off the ribs.

Body position: shoulders directly above your hands, arms straight, elbows locked.

Push with your body weight, not your arms. This is the difference between lasting two minutes and lasting ten.

Depth: at least 5 centimetres — about 2 inches — and not more than 6 centimetres.

That is deeper than people expect and it is correct. Ribs sometimes crack. It is not a reason to stop.

Rate: 100 to 120 compressions per minute.

Allow full recoil. **Let the chest come all the way back up between compressions without taking your hands off. Incomplete recoil is one of the commonest errors and it reduces effectiveness substantially, because the heart refills during the upstroke.

And minimise interruptions. Every pause costs pressure that takes several compressions to rebuild.

5. Breaths, or not

If you are untrained, or unwilling, or it is a stranger: do compressions only.

Hands-only CPR is the recommended approach for the general public witnessing an adult collapse, and it is substantially better than nothing and comparable to full CPR in the first minutes for an adult who has arrested suddenly.

If you are trained and willing: 30 compressions, then 2 breaths, repeated.

**For breaths: head tilted back, chin lifted, pinch the nose, seal your mouth over theirs, and blow steadily for about one second until the chest visibly rises. Two breaths, then straight back to compressions.

Do not spend more than about ten seconds on the two breaths.

6. Keep going

Until: the person shows clear signs of life, a defibrillator is attached and tells you to stop, professional help takes over, or you are physically unable to continue.

And swap with somebody else every two minutes if you can. Quality drops measurably after about two minutes and the person doing it does not notice.

The rhythm

Songs at roughly the right tempo, and this is genuinely how people are taught: Stayin' Alive, Baby Shark, or Another One Bites the Dust.

Any of them will hold you at about 100 to 120.

The defibrillator

And this is the item that most changes outcomes, so it deserves emphasis.

A public access defibrillator — an AED — is designed to be used by anybody with no training at all.

You open it. It talks to you. It tells you exactly what to do, step by step.

It will not shock somebody who does not need it. It analyses the rhythm and only delivers a shock if the rhythm is shockable, which removes the fear that stops people using them.

How to use one:

Turn it on and follow the voice.

Bare the chest. Dry it if wet. Remove or cut through clothing.

Place the pads as shown on the pictures — one below the right collarbone, one on the left side below the armpit.

Stand clear when it says to analyse and when it says to shock.

Then resume compressions immediately when told.

Survival falls with every minute that passes before defibrillation. Getting one attached fast is the single biggest improvement available after compressions.

Children and infants

Different, and worth knowing briefly.

Children usually arrest because of a breathing problem rather than a cardiac one, which means breaths matter more.

If you are trained: give 5 initial rescue breaths, then 30 compressions to 2 breaths.

Compression depth: about one third of the depth of the chest.

Child (roughly one year to puberty): one or two hands, whichever gives adequate depth.

Infant (under one year): two fingers, or two thumbs with hands encircling the chest.

Rate is the same: 100 to 120.

And the same principle: if you are untrained and there is no other option, compressions are better than nothing.

Drowning

One important exception (3.6).

In drowning, the cause is lack of oxygen, so breaths matter more.

If trained: give 5 rescue breaths first, then standard CPR.

What people worry about

Four things, answered.

"What if they are not really in arrest?" A conscious person will react and you will stop. It happens and it is not a disaster.

"What if I break their ribs?" You may. It is common, it heals, and it is not a reason to stop or to compress less deeply.

"What if I am doing it wrong?" Imperfect compressions circulate blood. No compressions do not.

"What about legal risk?" Good faith assistance is protected in many jurisdictions, and India has Good Samaritan protections for bystanders.

What to actually do this week

Three things, and the first takes two minutes.

Find your nearest defibrillator. Many are mapped in apps and on local registers. Knowing where one is, in the place you spend most time, is worth having.

Practise the position on a cushion. Hands, arms straight, body weight. Ninety seconds.

And do a hands-on course if you can. Many are free or nearly free, they take a few hours, and the physical practice is the part reading cannot give you.

What to do with this page

Not responding and not breathing normally: start compressions. Gasping is not breathing.

Centre of the chest, at least 5 cm, 100–120 a minute, full recoil, minimal interruption.

Hands-only is fine and is recommended for untrained bystanders.

Get a defibrillator attached as fast as possible — it talks you through it and will not shock somebody who does not need it.

And you cannot make them worse. That is the sentence that gets people to start, and starting is the whole thing.

Next: 3.3 — heart attack and stroke, where the wins are in recognising them early.