In a patient with hemodynamically unstable supraventricular tachycardia, which first-line intervention is indicated?

In a patient with hemodynamically unstable supraventricular tachycardia, which first-line intervention is indicated?

• A. Adenosine infusion
• B. Vagal maneuvers only
• C. Direct current cardioversion
• D. Observation

Answer: (C)

When a patient with supraventricular tachycardia is hemodynamically unstable, the priority is to rapidly restore perfusion and rhythm. Synchronized direct current cardioversion achieves that quickly and reliably, making it the first-line intervention. Adenosine is useful for stable, narrow-complex SVT to transiently block AV conduction and may terminate some reentrant tachycardias, but delaying treatment to give a drug in an unstable patient risks sustained hypoperfusion. Vagal maneuvers are noninvasive and can help in stable cases, yet they are unlikely to resolve instability and should not delay definitive treatment. Observation offers no active correction of the dangerous rhythm. In practice, use a synchronized electrical shock at an appropriate energy level and proceed promptly to restore a stable rhythm, with consideration of sedation if time and patient status allow.

When a patient with supraventricular tachycardia is hemodynamically unstable, the priority is to rapidly restore perfusion and rhythm. Synchronized direct current cardioversion achieves that quickly and reliably, making it the first-line intervention.

Adenosine is useful for stable, narrow-complex SVT to transiently block AV conduction and may terminate some reentrant tachycardias, but delaying treatment to give a drug in an unstable patient risks sustained hypoperfusion. Vagal maneuvers are noninvasive and can help in stable cases, yet they are unlikely to resolve instability and should not delay definitive treatment. Observation offers no active correction of the dangerous rhythm.

In practice, use a synchronized electrical shock at an appropriate energy level and proceed promptly to restore a stable rhythm, with consideration of sedation if time and patient status allow.