What is the priority intervention for a patient with narrow-complex tachycardia and low blood pressure?

In the scenario of a patient with narrow-complex tachycardia and low blood pressure, performing immediate synchronized cardioversion is the most critical intervention. Narrow-complex tachycardia typically suggests a reentrant tachycardia or atrial fibrillation with a rapid ventricular response, both of which can lead to reduced cardiac output and subsequently low blood pressure. Synchronized cardioversion is a definitive treatment aimed at restoring normal sinus rhythm, which can quickly improve hemodynamics and stabilize blood pressure.

This intervention is particularly important when the patient is experiencing symptoms consistent with poor perfusion, such as hypotension. Synchronized cardioversion delivers a controlled electrical shock at a specific point in the cardiac cycle, ensuring that it targets the heart when it is most susceptible to resetting the rhythm without causing further instability.

While other options, such as administering IV fluids or initiating vagal maneuvers, might be part of the broader management in different contexts, they do not address the immediate concern of unstable tachycardia with low blood pressure as decisively as synchronized cardioversion does. Administering oxygen can also be beneficial but does not tackle the underlying issue of the tachycardia itself. Thus, synchronized cardioversion is prioritized in this