A 32-year-old woman comes to the emergency department complaining of sudden-onset palpitations and mild shortness of breath that started 30 minutes ago. She has no significant past medical history. Her temperature is 37.0°C (98.6°F), blood pressure is 118/76 mmHg, pulse is 185/min, and respiratory rate is 18/min. Pulse oximetry is 99% on room air. An electrocardiogram reveals a regular, narrow-complex tachycardia with no discernible P waves. Assuming each subsequent intervention fails to terminate the arrhythmia and the patient remains hemodynamically stable until the final step, arrange the following management options in the correct sequential order from first to last according to standard treatment algorithms.
- 1Instruct the patient to perform a Valsalva maneuver
- 2Administer rapid intravenous adenosine
- 3Administer intravenous diltiazem
- 4Perform synchronized electrical cardioversion
Answer
The correct sequential order for managing stable, regular, narrow-complex tachycardia is: Valsalva maneuver, followed by intravenous adenosine, followed by intravenous diltiazem, and finally synchronized electrical cardioversion.
The management of stable, regular, narrow-complex tachycardia (such as AV nodal reentrant tachycardia) follows a well-defined sequence. Because the patient is hemodynamically stable (normal blood pressure, mentation, and perfusion), non-invasive vagal maneuvers (e.g., Valsalva) should be attempted first to increase vagal tone and block the AV node. If this fails, rapid intravenous adenosine is the first-line medication due to its short half-life and high efficacy in terminating AV node-dependent arrhythmias. If adenosine is ineffective or the arrhythmia recurs, longer-acting AV nodal blocking agents like intravenous diltiazem or metoprolol are used. Synchronized electrical cardioversion is reserved as a last resort for refractory stable SVT or is used immediately if the patient becomes unstable.
Step-by-Step Solution
Key Concept
The stepwise management of hemodynamically stable paroxysmal supraventricular tachycardia (PSVT) prioritizes vagal maneuvers, followed by adenosine, then non-dihydropyridine calcium channel blockers or beta-blockers, reserving cardioversion for refractory or unstable cases.
Estimated Time:1m 30s