The management of bradycardia is governed by two considerations:
- the presence of adverse signs:
- systolic blood pressure less than 90 mmHg
- heart rate less than 40 per minute
- heart failure
- ventricular arrhythmias requiring suppression
- the risk of asystole:
- recent episode of asystole
- ventricular pauses more than 3 seconds
- mobitz type 2 second degree heart block
- third degree heart block with broadened QRS complexes
For all patients, give high flow oxygen and establish i.v. access.
A) If one or more adverse signs are present, give 0.5 mg atropine and assess response.
- if response is inadequate, give further doses of atropine 0.5 mg at a time to a maximum of 3 mg
- if response is still inadequate, arrange external transcutaneous pacing
- if transcutaneous pacing is not available, start an epinephrine infusion at 2-10 mcg per minute (10 mcg is equivalent to 0.1 mls of 1:10,000 epinephrine)
- obtain expert help and arrange transvenous pacing
- if response is adequate, go to point B)
B) If no adverse signs are present, determine the risk of asystole.
- if no risk of asystole, arrange for the patient to be observed
- if there is a risk of asystole, consider interim measures such as atropine, epinephrine and transcutaneous pacing
- obtain expert help and arrange transvenous pacing