ESMOLOL HYDROCHLORIDE
(ess'moe-lol)
Brevibloc
Classifications: autonomic nervous system agent; beta-adrenergic antagonist (blocking agent, sympatholytic)
Prototype: Propranolol
Pregnancy Category: C

Availability

10 mg/mL, 250 mg/mL injection

Actions

Ultrashort-acting beta₁-adrenergic blocking agent with cardioselective properties but devoid of intrinsic sympathetic activity (ISA) or membrane-stabilizing (quinidine-like) activity. Hemodynamic effects are mild, with potency as a beta blocker about 1/100 that of propranolol. Inhibits the agonist effect of catecholamines by competitive binding at beta-adrenergic receptors.

Therapeutic Effects

Blocks sympathetically mediated increases in cardiac rate and BP since it binds predominantly to beta₁-receptors in cardiac tissue.

Uses

Supraventricular tachyarrhythmias (SVT) in perioperative and postoperative periods or in other critical situations. Also short-term treatment of noncompensating sinus tachycardia and in the control of heart rate for patients with MI.

Unlabeled Uses

Moderate postoperative hypertension; treatment of intense transient adrenergic response to surgical stress in cardiac as well as noncardiac surgery.

Contraindications

Cardiac failure, heart block greater than first degree, sinus bradycardia, cardiogenic shock; pregnancy (category C), lactation. Safety in children is not established.

Cautious Use

History of allergy or bronchial asthma, bronchospasm, emphysema; CHF; diabetes mellitus; kidney function impairment.

Route & Dosage

Supraventricular Tachyarrhythmias
Adult: IV 500 mcg/kg loading dose followed by 50 mcg/kg/min, may increase dose q5–10min prn (max: 200 mcg/kg/min)

Administration

Note: Do not use the 2500 mg ampul for direct IV injection.

Intravenous

PREPARE: Direct: Use the 10 mg/mL vial undiluted for the loading dose. IV Infusion: Prepare maintenance infusion by adding 250 mL of diluent to each 2500 mg ampul to yield 10 mg/mL. Compatible diluents include D5W, D5/RL, D5/NS, D5/.45NS, RL.

ADMINISTER: Direct: Give loading dose over 1 min. IV Infusion: Give maintenance infusion over 4 min. If adequate response is noted, continue maintenance infusion with periodic adjustments as needed. If an adequate response has not occurred, repeat loading dose and follow with an increased maintenance infusion of 100 mcg/kg/min. May continue titration cycle with same loading dose while increasing maintenance infusion by 50 mcg/kg/min until desired end point is near. Then omit loading dose and titrate maintenance dose up or down by 25 to 50 mcg/kg/min until desired heart rate is reached.

INCOMPATIBILITIES Solution/Additive: Procainamide. Y-site: Amphotericin B cholesteryl, furosemide, warfarin.

Diluted infusion solution is stable for at least 24 h at room temperature.

Adverse Effects (1%)

CNS: Headache, dizziness, somnolence, confusion, agitation. CV: Hypotension (dose related), cold hands and feet, bradyarrhythmias, flushing, myocardial depression. GI: Nausea, vomiting. Respiratory: Dyspnea, chest pain, rhonchi, bronchospasm. Skin: Infusion site inflammation (redness, swelling, induration).

Interactions

Drug: May increase digoxin IV levels 10–20%; morphine IV may increase esmolol levels by 45%; succinylcholine may prolong neuromuscular blockade.

Pharmacokinetics

Onset: <5 min. Peak: 10–20 min. Duration: 10–30 min. Metabolism: Rapidly hydrolyzed by RBC esterases. Elimination: Eliminated in urine. Half-Life: 9 min.

Nursing Implications

Assessment & Drug Effects

Monitor BP, pulse, ECG, during esmolol infusion. Hypotension may have its onset during the initial titration phase; thereafter the risk increases with increasing doses. Usually the hypotension experienced during esmolol infusion is resolved within 30 min after infusion is reduced or discontinued.
Change injection site if local reaction occurs. IV site reactions (burning, erythema) or diaphoresis may develop during infusion. Both reactions are temporary. Blood chemistry abnormalities have not been reported.
Overdose symptoms: Discontinue administration if the following symptoms occur: bradycardia, severe dizziness or drowsiness, dyspnea, bluish-colored fingernails or palms of hands, seizures.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug