Adult CPR and AED

How to recognise cardiac arrest in adults, start CPR promptly and use an automated external defibrillator (AED).

What is adult CPR & AED?

Cardiac arrest happens when the heart suddenly stops pumping effectively, causing loss of consciousness and absence of normal breathing; without CPR and defibrillation, brain damage and death occur within minutes. CPR keeps blood flowing to vital organs until an AED and advanced care can restore a viable rhythm.

AEDs are designed to be used by lay responders with minimal training; they analyse the heart rhythm and advise or deliver a shock if appropriate, significantly improving survival when used early. First aiders should be confident to use any available AED without delay.

Out-of-hospital cardiac arrest survival is strongly linked to early recognition, early CPR and early defibrillation, with bystander CPR doubling or tripling survival in some studies.

Who needs this skill?

Any place where people gather - workplaces, clinics, venues, public spaces - benefits from accessible AEDs and staff trained in adult CPR.

Health & Social Care

In health and social care, resuscitation training is mandatory for many roles, and staff must follow Resuscitation Council UK guidelines, local DNACPR policies and escalation pathways.

Licensed venues & nightlife

In nightlife and licensed venues, crowd demographics and alcohol use increase the importance of rapid recognition of collapse, early CPR and AED use, especially in younger adults where cardiac arrest may be unexpected.

Schools

Schools increasingly host AEDs and community events; staff trained in adult CPR and AED use can respond not only to colleagues but also to parents and visitors using school facilities.

Workplaces

In workplaces, employers should consider AED provision based on risk assessments and ensure staff know their locations and how to use them; even untrained bystanders can follow AED prompts.

How to manage adult CPR & AED

These steps show how to recognise adult cardiac arrest, start CPR promptly and use an AED with confidence.

1

Recognise cardiac arrest and call 999

If an adult collapses, is unresponsive and not breathing normally (no breathing or only occasional gasps), suspect cardiac arrest and call 999 immediately, putting the phone on speaker if possible.

Tell the call-handler you think it is a cardiac arrest; they can coach you through CPR and direct you to the nearest AED.

2

Start chest compressions in the centre of the chest

Kneel beside the casualty, place the heel of one hand in the centre of the chest on the lower half of the breastbone, place your other hand on top and interlock fingers; press down 5-6 cm at a rate of 100-120 compressions per minute, allowing full recoil.

Minimise interruptions to compressions; high-quality, continuous compressions are critical.

3

Add rescue breaths if trained and willing

If you are trained and willing, after 30 compressions open the airway and give 2 rescue breaths, watching for the chest to rise, then resume compressions.

If you cannot or do not wish to give breaths, perform compression-only CPR; this is still much better than doing nothing.

4

Use an AED as soon as it arrives

Switch on the AED, follow the voice and visual prompts, expose the chest, attach pads as shown and stand clear when the device analyses the rhythm and delivers a shock if advised.

Resume CPR immediately after any shock or 'no shock' advice, following AED prompts until help arrives or the casualty shows signs of life.

This guide is a learning reference only. It does not replace attended, assessed first aid training.

Qualifying courses

These courses all include adult CPR and AED skills, with clinical and FREC programmes adding advanced resuscitation interventions. Choose the course that matches your role, sector, and the level of clinical practice required.

Qualsafe Level 2 Award in Basic Life Support and Safe Use of an Automated External Defibrillator (RQF)

Standalone BLS & AED update

Half day

1 year

Common questions

Practical answers for employers, venue managers, and healthcare teams about adult CPR & AED training.

Can't find your answer? Contact us.

A yellow automated external defibrillator (AED) with a black handle and three indicator lights is connected by a cable to a pouch containing adult electrode pads, which shows illustrated instructions for pad placement on a person’s chest. - on localmedic

B

Can I harm someone by using an AED if they are not in cardiac arrest?

Modern AEDs analyse heart rhythm and will not deliver a shock unless a shockable rhythm is present. You should not delay using an AED if you suspect cardiac arrest.

B

What if I am worried about doing CPR incorrectly?

Any attempt at CPR is better than no attempt; doing something significantly improves the casualty’s chances, and emergency call-handlers can guide you.

B

Do I need formal training before I can use an AED?

No; AEDs are designed for public use, with clear prompts and safety features. Formal training improves confidence and quality but is not a legal requirement to use an AED in an emergency.

B

Should I stop CPR when I get tired?

If you are alone, do your best and take brief pauses if absolutely necessary; if others are present, swap every 1-2 minutes to reduce fatigue while keeping interruptions minimal.

B

How can organisations maximise the impact of AEDs?

AEDs should be clearly signposted, registered with local schemes, maintained regularly and included in drills; staff should know where they are and feel empowered to use them.