DC Dysrhythmia Emergency Response & Intervention 2 — Questions and Answers
Question 1: A patient in pulseless ventricular tachycardia is unresponsive. What is the correct immediate action?
- Administer adenosine 6 mg IV push
- Perform synchronized cardioversion at 100J
- Initiate CPR and defibrillate with 200J biphasic (Correct answer)
- Start a dopamine infusion
Correct answer: Initiate CPR and defibrillate with 200J biphasic
Pulseless VT is treated as cardiac arrest — begin CPR and deliver unsynchronized defibrillation immediately.
Question 2: During resuscitation of a patient in ventricular fibrillation, which drug is given after the second failed defibrillation attempt?
- Lidocaine 1.5 mg/kg IV
- Amiodarone 300 mg IV bolus (Correct answer)
- Atropine 1 mg IV push
- Magnesium sulfate 2 g IV
Correct answer: Amiodarone 300 mg IV bolus
ACLS guidelines recommend amiodarone 300 mg IV bolus after the second shock in refractory VF/pulseless VT.
Question 3: A patient with symptomatic third-degree heart block has a heart rate of 28 bpm and is hypotensive. What is the priority intervention?
- IV amiodarone infusion
- Transcutaneous pacing (Correct answer)
- Carotid sinus massage
- Adenosine 6 mg IV push
Correct answer: Transcutaneous pacing
Transcutaneous pacing is the priority bridge intervention for hemodynamically unstable complete heart block.
Question 4: Which ECG finding indicates that a synchronized cardioversion attempt should NOT proceed as planned?
- The rhythm is atrial flutter at 150 bpm
- No sync marker is visible on the R-wave (Correct answer)
- The patient received oxygen 2 minutes ago
- The QRS duration is greater than 120 ms
Correct answer: No sync marker is visible on the R-wave
If the defibrillator is not detecting and marking R-waves, the sync mode must be confirmed before delivering the shock.
Question 5: A patient develops torsades de pointes with a pulse and intermittent hypotension. What is the initial pharmacologic intervention?
- IV magnesium sulfate 2 g over 15 minutes (Correct answer)
- IV amiodarone 150 mg over 10 minutes
- IV adenosine 6 mg rapid push
- IV atropine 0.5 mg
Correct answer: IV magnesium sulfate 2 g over 15 minutes
Magnesium sulfate 1–2 g IV is the treatment of choice for torsades de pointes to stabilize cardiac membrane potential.
Question 6: During a code, the team leader calls for a rhythm check after two minutes of CPR and the monitor shows asystole. What is the next step?
- Deliver an immediate 360J shock
- Resume CPR and administer epinephrine 1 mg IV (Correct answer)
- Administer atropine 3 mg IV and wait 2 minutes
- Perform synchronized cardioversion at 50J
Correct answer: Resume CPR and administer epinephrine 1 mg IV
Asystole is a non-shockable rhythm; resume high-quality CPR immediately and administer epinephrine every 3–5 minutes.
Question 7: A nurse is preparing to cardiovert a conscious patient with unstable atrial fibrillation. Which action is essential before delivering the shock?
- Administer IV adenosine to slow the ventricular rate first
- Ensure the defibrillator is set to 'sync' mode (Correct answer)
- Confirm the defibrillator is set to unsynchronized mode
- Place the pads in the anteroposterior position only
Correct answer: Ensure the defibrillator is set to 'sync' mode
Synchronized mode must be selected for cardioversion so the shock is delivered on the R-wave and avoids inducing VF.
DC Dysrhythmia Emergency Response & Intervention 2
A patient in pulseless ventricular tachycardia is unresponsive.
What is the correct immediate action?