ACLS Bradycardia Algorithm: Atropine, Pacing and Infusions

A slow heart rate is only a problem if it is causing harm. The ACLS bradycardia algorithm is built around that single question, and it is one of the core cases on an ACLS course.

Assess first

Maintain the airway, give oxygen if the patient is hypoxaemic, attach the monitor, check blood pressure and oxygen saturation, obtain IV access and a 12-lead ECG. Look for the cause: medications, ischaemia, electrolyte problems and hypoxia are common. See the systematic approach.

Is it causing harm?

Signs that bradycardia is compromising the patient: hypotension, acutely altered mental status, signs of shock, ischaemic chest discomfort or acute heart failure. If none are present, monitor and observe.

Treatment when it is

1. Atropine first, repeated at intervals up to a maximum dose. See ACLS drugs.
2. If atropine is ineffective: transcutaneous pacing, or an infusion of dopamine or adrenaline. See pacing.
3. Seek expert consultation and consider transvenous pacing.

Heart blocks

High-degree blocks — Mobitz type II second-degree and third-degree block — are less likely to respond to atropine, so be ready to pace early. Recognising them is covered in ACLS rhythms.

If the patient arrests

Loss of pulse moves you to the non-shockable pathway. For the fast-rhythm equivalent, see the tachycardia algorithm.

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 Asystole and PEA: The Non-Shockable Pathway
• 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

What is the first drug for symptomatic bradycardia?

Atropine.

What if atropine does not work?

Transcutaneous pacing, or a dopamine or adrenaline infusion, with expert consultation.

Do you treat bradycardia without symptoms?

Not urgently; monitor and look for the cause.

Does atropine work for third-degree block?

It is less likely to be effective; be ready to pace.

What are the signs bradycardia is causing harm?

Hypotension, altered mental status, shock, ischaemic chest pain or acute heart failure.

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.