Peri-Arrest Rhythms: Bradycardia

Key points

• Resuscitation Council UK (2021): assess with an ABCDE approach; management is guided by (1) life-threatening adverse features and (2) the risk of asystole.
• Adverse features — shock (SBP <90 mmHg, pallor, sweating, cold clammy peripheries, impaired consciousness), syncope, myocardial ischaemia, heart failure. If present, give atropine 500 micrograms IV, repeated every 3–5 minutes to a maximum of 3 mg.
• Risk of asystole — recent asystole, Mobitz II AV block, complete (third-degree) heart block especially with broad-complex QRS, or a ventricular pause >3 seconds. If present, or if atropine is ineffective, arrange transvenous pacing; seek expert help even if the patient initially responds.
• While awaiting transvenous pacing, interim measures: transcutaneous pacing, OR isoprenaline 5 micrograms/min IV, OR adrenaline 2–10 micrograms/min IV. Alternatives: aminophylline (inferior MI, cardiac transplant, spinal cord injury), dopamine, glucagon (beta-blocker or calcium-channel-blocker toxicity), glycopyrronium.
• Do NOT give atropine to a patient with a cardiac transplant (risk of high-grade AV block or sinus arrest) — use aminophylline. Where atropine at maximal dose is ineffective, start transcutaneous pacing immediately.

Decision points in this pathway

• Adverse signs present?
• Satisfactory response to atropine?
• Potential risk of asystole (complete heart block with broad complex QRS · recent asystole · Mobitz type II AV block · ventricular pause >3 seconds)?

The full step-by-step algorithm, including what to do at each branch, opens in the app for approved members.