ACLS - Advanced Cardiovascular Life Support Tachycardia and Bradycardia Algorithms Questions and Answers — Questions and Answers
Question 1: A 58-year-old male presents with dizziness and shortness of breath. His heart rate is 40 bpm, blood pressure is 80/50 mmHg, and he appears pale and diaphoretic. The monitor shows a third-degree AV block. According to the ACLS Bradycardia Algorithm, which intervention should be prioritized after initial stabilization (airway, oxygen)?
- Administering a 1 mg IV bolus of atropine.
- Requesting immediate expert consultation for transvenous pacing.
- Administering a dopamine infusion at 2 mcg/kg/min.
- Preparing for immediate transcutaneous pacing. (Correct answer)
Correct answer: Preparing for immediate transcutaneous pacing.
In a patient with symptomatic bradycardia due to a high-degree AV block (like third-degree block) and signs of poor perfusion (hypotension, altered mental status), atropine is unlikely to be effective. The ACLS algorithm indicates immediate preparation for transcutaneous pacing as the next critical step to increase the heart rate and improve perfusion.
Question 2: A patient with a regular, narrow-complex tachycardia at a rate of 180 bpm is stable but symptomatic. Vagal maneuvers have been ineffective. What is the correct initial drug and dose according to the ACLS Tachycardia Algorithm?
- Amiodarone 150 mg IV over 10 minutes.
- Adenosine 6 mg rapid IV push. (Correct answer)
- Verapamil 2.5 mg IV bolus over 2 minutes.
- Metoprolol 5 mg slow IV push.
Correct answer: Adenosine 6 mg rapid IV push.
For stable, regular, narrow-complex supraventricular tachycardia (SVT) that does not respond to vagal maneuvers, the first-line pharmacologic agent is adenosine. The correct initial dose is 6 mg administered as a rapid IV push, followed by a saline flush.
Question 3: Which of the following is a primary indication for immediate synchronized cardioversion in the Tachycardia Algorithm?
- A stable patient with wide-complex tachycardia.
- An anxious patient with sinus tachycardia at 110 bpm.
- An unstable patient with persistent tachyarrhythmia causing hypotension. (Correct answer)
- A patient with atrial fibrillation whose heart rate responds to diltiazem.
Correct answer: An unstable patient with persistent tachyarrhythmia causing hypotension.
The key decision point in the Tachycardia Algorithm is patient stability. Immediate synchronized cardioversion is indicated for patients who are unstable due to a persistent tachyarrhythmia. Signs of instability include hypotension, acutely altered mental status, signs of shock, ischemic chest discomfort, or acute heart failure.
Question 4: According to the most recent ACLS guidelines for adult symptomatic bradycardia, what is the correct first dose of atropine?
- 0.5 mg IV, repeat every 3-5 minutes.
- 1 mg IV, repeat every 3-5 minutes. (Correct answer)
- 1.5 mg IV, one time only.
- 0.25 mg IV, repeat every 5-10 minutes.
Correct answer: 1 mg IV, repeat every 3-5 minutes.
The ACLS guidelines updated the single-dose administration of atropine for symptomatic bradycardia from 0.5 mg to 1 mg. The correct procedure is to give a 1 mg bolus IV and repeat every 3-5 minutes as needed, up to a maximum total dose of 3 mg.
Question 5: A 66-year-old female is in the emergency department with palpitations. The monitor shows a regular, wide-complex tachycardia (QRS > 0.12 sec) at a rate of 160 bpm. Her blood pressure is 118/76 mmHg and she is alert and oriented. Which of the following interventions can be considered for this stable patient?
- Immediate unsynchronized shock at 200 joules.
- Administration of adenosine. (Correct answer)
- Initiation of transcutaneous pacing.
- Administration of atropine 1 mg IV.
Correct answer: Administration of adenosine.
For a stable patient with a regular, monomorphic wide-complex tachycardia, the ACLS algorithm allows for the consideration of adenosine. Antiarrhythmic infusions like procainamide or amiodarone are also options. Immediate shock is reserved for unstable patients, and pacing or atropine would be inappropriate for tachycardia.
Question 6: If atropine is ineffective in treating a patient with symptomatic bradycardia and poor perfusion, which of the following are the appropriate next-line treatment options according to the ACLS algorithm?
- Administer a fluid bolus and reassess.
- Wait 10 minutes and administer another dose of atropine.
- Transcutaneous pacing or an infusion of dopamine or epinephrine. (Correct answer)
- Immediate synchronized cardioversion.
Correct answer: Transcutaneous pacing or an infusion of dopamine or epinephrine.
When atropine fails to resolve symptomatic bradycardia, the ACLS algorithm directs providers to consider second-line therapies. These include transcutaneous pacing (TCP) or initiating an IV infusion of a chronotropic agent like dopamine (5-20 mcg/kg/min) or epinephrine (2-10 mcg/min).
ACLS - Advanced Cardiovascular Life Support Tachycardia and Bradycardia Algorithms Questions and Answers
A 58-year-old male presents with dizziness and shortness of breath.
His heart rate is 40 bpm, blood pressure is 80/50 mmHg, and he appears pale and diaphoretic.
The monitor shows a third-degree AV block.
According to the ACLS Bradycardia Algorithm, which intervention should be prioritized after initial stabilization (airway, oxygen)?