Esmolol

Provider Level

RN/Paramedic

Class

Beta-1 selective adrenergic antagonist (Beta-blocker), Class II antiarrhythmic

Mechanism of Action

Competitively blocks beta-1 adrenergic receptors with minimal effect on beta-2 receptors at therapeutic doses. Decreases heart rate, AV node conduction, and myocardial contractility. Ultra-short acting due to rapid hydrolysis by red blood cell esterases.

Indications

Supraventricular tachycardia (SVT), atrial fibrillation or atrial flutter with rapid ventricular response, acute hypertension.

Contraindications

Sinus bradycardia, heart block greater than first degree, cardiogenic shock, decompensated heart failure, severe active bronchospasm.

Routes

IV, IO

Onset / Duration

Onset: 1 to 2 minutes. Duration: 10 to 20 minutes after infusion is discontinued.

Adverse Effects

Hypotension (highly common), bradycardia, heart block, dizziness, diaphoresis, bronchospasm (at higher doses or in susceptible patients).

Precautions & Interactions

Continuous ECG and blood pressure monitoring required. Use with extreme caution in patients with reactive airway disease, WPW syndrome, or concurrent use of calcium channel blockers. May mask tachycardia associated with hypoglycemia or hypovolemia.

Special Considerations

Authorized for RN/Paramedic levels. Ultra-short half-life (approximately 9 minutes) allows for rapid titration and rapid reversal of adverse effects upon discontinuation. Can cause severe tissue necrosis if extravasation occurs. Do not mix with sodium bicarbonate.