ACLS — Advanced Cardiovascular Life Support — All Questions
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A patient has a heart rate of 38 with hypotension and altered mental status. What is the first-line drug?
- a.Adenosine 6 mg rapid IV push
- b.Atropine 1 mg IV✓
- c.Amiodarone 300 mg IV
- d.Epinephrine 1 mg IV push
This is symptomatic bradycardia, and atropine 1 mg IV (repeatable every 3-5 minutes to a maximum of 3 mg) is the first-line drug. Atropine reduces vagal tone to raise the rate. If atropine is ineffective, the next steps are transcutaneous pacing or an epinephrine or dopamine infusion. A 1 mg epinephrine push is the arrest dose and is not used for a perfusing bradycardia.
A patient with wide-complex tachycardia has a pulse but is hypotensive and confused. The appropriate treatment is:
- a.Unsynchronized defibrillation
- b.Synchronized cardioversion✓
- c.Adenosine only, then observe
- d.No treatment; continue to observe
An unstable tachycardia WITH a pulse (hypotension, altered mental status, ischemic chest pain, or signs of shock) is treated with immediate synchronized cardioversion. Synchronization times the shock to the R wave to avoid delivering energy during the vulnerable T-wave period, which could induce VF. Unsynchronized defibrillation is reserved for pulseless VT/VF.
Atropine has failed to improve a patient's symptomatic bradycardia. Appropriate next steps include:
- a.Defibrillate the patient
- b.Transcutaneous pacing or a dopamine/epinephrine infusion✓
- c.Give adenosine 6 mg rapid IV push
- d.Perform synchronized cardioversion
When atropine does not resolve symptomatic bradycardia, escalate to transcutaneous pacing and/or a dopamine or epinephrine infusion to support the rate and blood pressure while addressing the underlying cause. Defibrillation and cardioversion treat tachyarrhythmias, and adenosine slows the AV node — none are appropriate for a slow, poorly perfusing rhythm.