ACLS Asystole and PEA: The Non-Shockable Pathway

In asystole and pulseless electrical activity, a shock will not help. What helps is high-quality CPR, early adrenaline and, above all, finding and treating the cause. This pathway is taught and tested on every ACLS course.

Recognising the rhythms

Asystole is the absence of electrical activity; confirm it is not fine VF or a disconnected lead. PEA is an organised rhythm on the monitor with no palpable pulse. See ACLS rhythms.

The steps

1. Start or continue high-quality CPR.
2. Give adrenaline (epinephrine) as soon as feasible, then every 3 to 5 minutes. See ACLS drugs.
3. Check the rhythm every 2 minutes. If it becomes shockable, move to the VF and pulseless VT pathway.
4. Consider an advanced airway and use waveform capnography.
5. Treat reversible causes throughout.

Why the cause matters most

PEA in particular is often caused by something treatable: hypovolaemia, hypoxia, hyperkalaemia, tension pneumothorax, cardiac tamponade or pulmonary embolism. The team leader should say the list out loud and assign people to look — see the H’s and T’s.

If circulation returns

A pulse and a sudden, sustained rise in end-tidal CO2 are signs of return of spontaneous circulation; move to post-arrest care.

When efforts stop

Decisions to stop resuscitation involve the whole clinical picture and local policy. ACLS discusses the factors, including the value of capnography, but the decision rests with the treating team.

This guide summarises what the ACLS course teaches for education only. It is not a clinical protocol: follow the current American Heart Association guidelines, linked below, and your institution’s policies.

More ACLS guides: ACLS algorithms and skills

• ACLS Course in Abu Dhabi — dates, format and booking
• ACLS Algorithms Explained: Cardiac Arrest, Bradycardia, Tachycardia and Post-Arrest Care
• The ACLS Systematic Approach: BLS, Primary and Secondary Assessment
• ACLS Cardiac Arrest: VF and Pulseless VT (the Shockable Pathway)
• ACLS Bradycardia Algorithm: Atropine, Pacing and Infusions
• ACLS Tachycardia Algorithm: Stable vs Unstable Tachycardia
• ACLS Post-Cardiac Arrest Care: What Happens After ROSC
• The H's and T's of ACLS: Reversible Causes of Cardiac Arrest
• ACLS Drugs: Adrenaline, Amiodarone, Atropine, Adenosine and More
• ACLS Rhythms: The ECG Rhythms You Need to Recognise
• ACLS Airway Management: From Bag-Mask to Advanced Airway
• Waveform Capnography in ACLS: What End-Tidal CO2 Tells You
• Acute Coronary Syndromes in ACLS: Recognition and First Steps
• Acute Stroke in ACLS: Recognition, Timing and First Steps
• ACLS Megacode: How It Works and How to Pass as Team Leader
• ACLS Electrical Therapy: Defibrillation, Cardioversion and Pacing
• All ACLS guides, by topic

Other life support and first aid courses: BLS Course · PALS Course · First Aid Course · Training calendar

Frequently asked questions

Is asystole shockable?

No. Asystole and PEA are non-shockable.

When is adrenaline given in asystole?

As soon as feasible, then every 3 to 5 minutes.

What is PEA?

An organised rhythm on the monitor without a palpable pulse.

Why are reversible causes so important in PEA?

PEA is often caused by a treatable problem, and treating it may be the only route to survival.

What if asystole becomes VF?

Switch to the shockable pathway and defibrillate.

Sources and further reading

What we teach follows the awarding body and the UAE health authorities. For the definitive position on a course or licensing question, these are the places to check.

• CPR and ECC Guidelines — American Heart Association
• Advanced Cardiovascular Life Support (ACLS) — American Heart Association

Last reviewed 21 September 2026 by the training team at Safety First Medical Services, an American Heart Association training centre at Addax Office Tower, Al Reem Island, Abu Dhabi. Call +971 55 761 9841 or email training@safetyfirstmed.ae.