How to Do CPR and Use a Defibrillator (AED)

Adult CPR, step by step

1. 1

   Do the primary survey.

   Danger, response, airway, breathing. If they are not breathing normally, send a helper to call 999 and fetch an AED. On your own? Make the call yourself, get the AED if one is close, then return and start CPR.

2. 2

   Start chest compressions.

   Heel of one hand on the centre of the chest, on the breastbone. Lock the other hand over it, fingers interlinked. Kneel close, shoulders directly above the chest, arms straight.

3. 3

   Push hard, push fast: 30 times.

   Compress 5 to 6 cm deep, about the width of a credit card, at 100 to 120 compressions per minute, roughly two per second. Release fully between compressions without lifting your hands off: the recoil lets the heart refill.

4. 4

   Give 2 rescue breaths.

   Head tilt chin lift, pinch the nose, seal your mouth over theirs, and breathe in until the chest rises. If the first breath does not go in, re-tilt and try once more, then go straight back to compressions either way.

5. 5

   Continue 30:2 without stopping.

   Only stop if the casualty shows definite signs of life, the ambulance crew tells you they are taking over, or you are physically exhausted with nobody to relieve you. If a helper is available, swap after a cycle or every two minutes to stay effective.

If you cannot give rescue breaths

Blood or vomit around the mouth, or no face shield to hand, are reasons you may choose not to give breaths. Compression-only CPR is far better than nothing: keep pushing at 100 to 120 per minute and use a pocket mask if one arrives.

Using a defibrillator (AED)

An AED analyses the heart's rhythm and shocks it only if a shock can help, typically ventricular fibrillation, where the heart quivers instead of pumping. It cannot shock someone it should not: the machine decides, not you. You will find AEDs in phone boxes, stations, shopping centres and many workplaces.

1. 1

   Turn it on and follow the voice instructions.

   The machine talks you through everything.

2. 2

   Bare the chest.

   Use the kit's scissors on clothing. Dry a wet chest with the towel. Excess hair where a pad will sit? Use the razor: rough is fine, it does not need to be a clean shave.

3. 3

   Place the pads as shown on the pads themselves.

   One top right of the chest, one on the left side. The AED detects contact and starts analysing.

4. 4

   Stand clear when it says so.

   Nobody touches the casualty while it analyses or shocks. Then continue CPR when instructed: 30:2 for two minutes until it reanalyses.

CPR for children

With children the cause is more likely breathing (asthma, drowning, choking) than the heart, so oxygen comes first.

1. 1

   Give 5 initial rescue breaths first.

   Head tilt chin lift, but do not tilt a child's head as far back as an adult's.

2. 2

   Then 30 compressions with ONE hand.

   Centre of the chest, compress about a third of the chest depth, around 4 to 5 cm.

3. 3

   Continue 30:2.

   If an AED is advised, a child under 8 uses paediatric pads: one on the front centre of the chest, one on the back between the shoulder blades. From age 8, use adult pads normally. Only adult pads available for an under 8? Place them front and back like paediatric ones.

CPR for babies

1. 1

   Check response gently.

   Blow on the face, clap, squeeze and tickle hands and feet.

2. 2

   Open the airway to the NEUTRAL position.

   A baby's head tilted back too far closes the airway; too far forward does the same.

3. 3

   5 rescue breaths over mouth AND nose.

   Their features are small: seal your mouth over both and give little puffs of air.

4. 4

   Compressions with two fingers.

   Centre of the chest, a third of the chest depth, 30 compressions to 2 breaths, back to neutral position for every breath.

Common questions

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