You do not need training to use a defibrillator, and you cannot shock someone who does not need it. The machine analyses the heart rhythm and will only allow a shock if one is required. Turn it on and do what it says.
When to use one
An AED is for a person who is unresponsive and not breathing normally. That is the only situation. If they are breathing, they do not need it.
Start chest compressions immediately and keep going while someone else fetches and sets up the AED. Compressions stop only when the machine tells you to stand clear.
Why speed matters more than technique here: for the rhythm an AED treats, survival falls by roughly 10% for every minute without defibrillation. CPR alone will not restart that rhythm — it buys time until the shock arrives. Send someone for the AED the moment you recognise cardiac arrest.
Using it
- Turn it on. Everything after this is voice-prompted. Follow the prompts rather than your memory.
- Bare the chest and attach the pads as shown on the pad packaging.
- Stand clear when told to. Nobody touches the person during analysis or shock — call it loudly and look before you confirm.
- Deliver the shock if the machine advises one.
- Resume compressions immediately and keep following the prompts until paramedics take over or the person starts breathing normally.
Leave the pads on. Paramedics will want them and the machine’s recorded data.
Where the pads go
Standard placement is one pad below the right collarbone and one on the left side of the chest below the armpit. The pads themselves carry a diagram — use it.
Front-and-back placement, one pad between the shoulder blades and one on the front of the chest, is also acceptable. For someone with large breasts, place the left pad to the side of the breast rather than on it.
Children and babies
- Over 8 years — a standard adult AED and adult pads are fine.
- Under 8, including infants — paediatric pads and a paediatric-capable AED are preferred.
- If you only have adult pads — use them. It is reasonable, and far better than no defibrillation at all. Keep the pads from touching each other; if they are too big to fit on the chest without touching, use the front-and-back position.
The situations people hesitate over
- Wet chest — dry it quickly before applying pads, but do not make a project of it. There are no reports of rescuers being harmed by defibrillating in wet conditions.
- Very hairy chest — hair may need removing for the pads to stick. Many AED kits include a razor for this. Again, speed over perfection.
- Pacemaker or implanted defibrillator — you will see or feel a lump under the skin. Do not put a pad over it; keep at least 8 cm clear.
- Medication patches — do not place a pad over a patch. Peel it off and wipe the skin first.
- Jewellery and piercings — leave them unless they are directly where a pad needs to go.
If you are alone
Call 000 first and put the phone on speaker. The call-taker can talk you through compressions while you wait, and may be able to direct you to the nearest registered AED. Do not leave the person to search for a machine you are not sure exists.
This is a summary of what is taught in class, not a substitute for training. Skills like this are assessed practically for a reason — reading about them is not the same as having done them. In a real emergency, call 000.
Learn it properly
AED use is taught and practised in HLTAID009 CPR and HLTAID011 first aid including CPR — the unit assessment requires following an AED’s prompts to deliver a shock. Best First Aid Training runs both at Parramatta, Penrith, Blacktown and Liverpool, and supplies defibrillators and first aid equipment.
Source: Australian and New Zealand Committee on Resuscitation, ANZCOR Guideline 7 — Automated External Defibrillation in Basic Life Support.
