Florida State Paramedic Practice Exam

What is the first-line medication for unstable WPW in paroxysmal supraventricular tachycardia (PSVT)?

1. Adenosine, 6mg

2. Verapamil

3. Amiodarone

4. Atropine

The correct answer is: Adenosine, 6mg

In cases of unstable Wolff-Parkinson-White (WPW) syndrome presenting with paroxysmal supraventricular tachycardia (PSVT), the first-line medication is adenosine. Adenosine works by temporarily blocking conduction through the atrioventricular (AV) node, which can effectively interrupt the reentrant circuits that characterize WPW. This action can rapidly restore normal sinus rhythm in patients experiencing PSVT. The effectiveness of adenosine is enhanced by its short half-life, allowing for a quick response in a critical situation, which is vital in unstable patients. Its administration can lead to transient asystole, which may help in resetting the heart rhythm. Other medications listed have their roles in different scenarios of arrhythmias but are not considered appropriate first-line treatments in the context of unstable WPW during PSVT. For example, calcium channel blockers like verapamil are contraindicated in patients with WPW, as they can potentially lead to severe ventricular rates. Similarly, amiodarone is typically reserved for more stable situations involving different arrhythmias, and atropine primarily addresses bradyarrhythmias, making it unsuitable for this particular case. Hence, adenosine is recognized as the preferred choice for