Ibutilide Fumarate

ibutilide fumarate (eye byu' ti lyed) Corvert Pregnancy Category C Drug class

Antiarrhythmic (predominately class III) Therapeutic actions

Prolongs cardiac action potential, increases atrial and ventricular refractoriness; produces mild slowing of sinus rate and AV conduction. Indications

•

Rapid conversion of atrial fibrillation or flutter of recent onset to sinus rhythm; most effective in arrhythmias of < 90 days' duration

Contraindications and cautions

• •

Contraindicated with hypersensitivity to ibutilide; second- or third-degree AV heart block, prolonged QTc intervals. Use cautiously with ventricular arrhythmias, pregnancy, lactation, renal and hepatic impairment.

Available forms

Solution—0.1 mg/mL Dosages ADULTS

< 60 kg: 0.1 mL/kg (0.01 mg/kg) infused over 10 min; may be repeated after 10 min if arrhythmia is not terminated. > 60 kg (132 lb): 1 vial (1 mg) infused over 10 min; may be repeated after 10 min if arrhythmia is not terminated. PEDIATRIC PATIENTS

Not recommended. Pharmacokinetics Route IV

Onset Immediate

Peak 10 min

Metabolism: Hepatic; T1/2: 6 hr Distribution: Crosses placenta, may be excreted in breast milk Excretion: Urine and feces IV facts

Preparation: May be diluted in 50 mL of diluent, 0.9% sodium chloride, or 5% dextrose injection; one 10-mL vial added to 50 mL of diluent yields a concentration of

0.017 mg/mL; may also be infused undiluted; diluted solution is stable for 24 hr at room temperature or for 48 hr refrigerated. Infusion: Infuse slowly over 10 min. Compatibilities: Compatible with 5% dextrose injection, 0.9% sodium chloride injection. Incompatibilities: Do not mix in solution with any other drugs. Adverse effects

• • •

CNS: Headache, light-headedness, dizziness, tingling in arms, numbness CV: Ventricular arrhythmias, hypotension, hypertension GI: Nausea

Interactions

Drug-drug • Increased risk of serious to life-threatening arrhythmias with disopyramide, quinidine, procainamide, amiodarone, sotalol; do not give together • Increased risk of proarrhythmias with phenothiazines, TCAs, antihistamines • Use cautiously with digoxin because ibutilide may mask digoxin cardiotoxicity Nursing considerations Assessment

• •

History: Hypersensitivity to ibutilide; second- or third-degree AV heart block, time of onset of atrial arrhythmia; prolonged QTc intervals; pregnancy, lactation; ventricular arrhythmias Physical: Orientation; BP, P, auscultation, ECG; R, adventitious sounds

Interventions

• • • • •

Determine time of onset of arrhythmia and potential benefit before beginning therapy. Conversion is more likely in patients with arrhythmias of short (< 90 days') duration. Ensure that patient is adequately anticoagulated, generally for at least 2 wk, if atrial fibrillation lasts > 2–3 days. Monitor ECG continually during and for at least 4 hr after administration. Be alert for possible arrhythmias, including PVCs, sinus tachycardia, sinus bradycardia, varying degrees of block at time of conversion. Keep emergency equipment readily available during and for at least 4 hr after administration. Provide appointments for continued follow-up, including ECG monitoring; tendency to revert to atrial arrhythmia after conversion increases with length of time patient was in abnormal rhythm.

Teaching points

•

This drug can only be given by IV infusion. You will need ECG monitoring during and for 4 hours after administration.

• • •

Arrange for follow-up medical evaluation, including ECG, which is important to monitor the effect of the drug on your heart. These side effects may occur: Rapid or irregular heartbeat (usually passes shortly), headache. Report chest pain, difficulty breathing, numbness or tingling.

Adverse effects in Italic are most common; those in Bold are life-threatening.