What is the maximum dose for the first adenosine administration in the stable narrow complex tachycardia protocol?

What is the maximum dose for the first adenosine administration in the stable narrow complex tachycardia protocol?

• A. 3 mg
• B. 9 mg
• C. 6 mg
• D. 12 mg

Answer: (C)

Adenosine is used in stable narrow complex tachycardia to transiently block AV nodal conduction and interrupt AV-nodal dependent reentrant circuits, delivering rapid, short-lived effects that help reveal or terminate the rhythm. Because it acts very quickly and has a short half-life, dosing starts low and is given as a rapid IV push with a saline flush to ensure it reaches the heart promptly. The standard starting dose is 6 mg, and this is the maximum for the first administration. If there’s no response after a short interval, a second dose of 12 mg can be given, and sometimes a third 12 mg dose may be used, but the initial dose remains 6 mg to balance effectiveness with safety.

Adenosine is used in stable narrow complex tachycardia to transiently block AV nodal conduction and interrupt AV-nodal dependent reentrant circuits, delivering rapid, short-lived effects that help reveal or terminate the rhythm. Because it acts very quickly and has a short half-life, dosing starts low and is given as a rapid IV push with a saline flush to ensure it reaches the heart promptly. The standard starting dose is 6 mg, and this is the maximum for the first administration. If there’s no response after a short interval, a second dose of 12 mg can be given, and sometimes a third 12 mg dose may be used, but the initial dose remains 6 mg to balance effectiveness with safety.