NREMT Paramedic Cognitive ExamCardiology & ResuscitationMedium
A 30-year-old male presents with palpitations, lightheadedness, and a heart rate of 190 bpm. His ECG shows a regular narrow-complex tachycardia. He is alert and oriented, BP 120/80 mmHg, SpO2 98%. Vagal maneuvers have been attempted and were unsuccessful. Which of the following is the MOST appropriate next intervention?
- AAdminister Diltiazem 0.25 mg/kg IV
- BAdminister Amiodarone 150 mg IV
- CPerform synchronized cardioversion
- DAdminister Adenosine 6 mg IV push
Show answer & explanationAnswer & explanation
Correct answer: D. Administer Adenosine 6 mg IV push
The patient has a stable narrow-complex tachycardia (SVT) as evidenced by his stable vital signs, alertness, and regular narrow QRS complexes. Since vagal maneuvers were unsuccessful, the next step in the ACLS algorithm for stable SVT is to administer Adenosine. Adenosine temporarily blocks the AV node, often terminating re-entrant tachycardias.
Why the other options are wrong
- A. Diltiazem is a calcium channel blocker used for rate control in atrial fibrillation/flutter or as an alternative to adenosine for SVT, but Adenosine is generally preferred as first-line after failed vagal maneuvers.
- B. Amiodarone is an antiarrhythmic used for a variety of tachyarrhythmias, but Adenosine is the first-line drug for stable narrow-complex tachycardia after failed vagal maneuvers.
- C. Synchronized cardioversion is reserved for unstable tachycardias or stable tachycardias refractory to medications.
Stable Narrow-Complex Tachycardia Treatment
Management involves vagal maneuvers, then adenosine, or calcium channel blockers/beta-blockers for rate control.
- Vagal maneuvers are first-line.
- Adenosine is drug of choice if vagal maneuvers fail.
- Ensure patient is hemodynamically stable.
Memory trick: Vagal's Vain, Adenosine's Aim, Diltiazem's Game!