Advanced Cardiac Life Support (ACLS): Bradycardia

ACLS: Bradycardia

1. Initial evaluation is as follows: ^{[1, 2, 3, 4, 5]}

• Assess appropriateness for clinical condition (pulse present and unstable).
• Heart rate typically less than 50 bpm in bradyarrhythmia

2. Initial intervention is as follows:

• Maintain patent airway and assist breathing, as needed.
• Administer oxygen if hypoxemic.
• Attach monitor/defibrillator.
• Monitor blood pressure and oximetry.
• Obtain intravenous (IV)/intraosseous (IO) access.
• Perform 12-lead electrocardiography (ECG); do not delay therapy.

3. Assess for signs of poor perfusion, as follows:

• Hypotension (systolic blood pressure [SBP] < 90 mm Hg)
• Acutely altered mental status
• Signs of shock
• Ischemic chest discomfort
• Acute heart failure

4. Therapeutic intervention is as follows:

• If poor perfusion present, administer atropine.
• If adequate perfusion present, monitor and observe.

5. Measures if atropine is ineffective are as follows:

• Transcutaneous pacing OR dopamine infusion OR epinephrine infusion
• Consider expert consultation and transvenous pacing.

Drug Therapy

Drug therapy is as follows:

• Atropine 1 mg IV q3-5min; maximum dose, 3 mg  NOTE: This is changed from the 2015 guidelines.
• Dopamine 2-20 μg/kg/min infusion; titrate to patient response; taper slowly.
• Epinephrine 2-10 μg/min infusion; titrate to patient response.

Atropine

Considerations for atropine administration are as follows:

• Not reliable for third-degree block or second-degree type II block
• Could potentially exacerbate the block by increasing sinoatrial (SA) node activation
• May be ineffective in patients after heart transplantation

Most Recent Guideline Changes

Changes from the 2015 guidelines include the following:

• The 2020 adult bradycardia algorithm increased the atropine dose to 1 mg (from 0.5-1 mg) but the frequency of dosing remains the same at every 3-5 minutes with a maximum of 3 mg.