Esmolol (Brevibloc) is indicated for which condition?

• A. Arrhythmia due to halogenated hydrocarbon exposure
• B. Hypertension due to seawater exposure
• C. Dehydration
• D. Anesthesia induction

Answer: (A)

The key idea is that esmolol is an ultra-short-acting beta-1 blocker used for rapid control of heart rate in acute tachyarrhythmias. Because it acts quickly and wears off just as fast, it’s ideal when you need precise, temporary control of an abnormal rhythm without a long-lasting effect.

Halogenated hydrocarbons (inhaled anesthetics) can provoke arrhythmias by increasing sympathetic activity and sensitizing the heart to catecholamines. Esmolol blocks the beta-1 receptors on the heart, slowing the heart rate and reducing AV nodal conduction, which helps stabilize the rhythm and improve hemodynamics in this situation. The short duration means you can titrate the effect and stop the drug promptly if the rhythm stabilizes or adverse effects occur.

Dehydration isn’t managed with a beta-blocker, hypertension from seawater exposure isn’t a typical indication for esmolol, and while esmolol can be used to blunt responses during anesthesia induction, the scenario described—arrhythmia due to halogenated hydrocarbons—best fits its rapid, short-acting antiarrhythmic use.