week 5 pam 103

Selective beta-blocker (Class II arrhythmic)

• Atenolol selectively blocks Beta-1 adrenergic receptors.
• It causes a reduction in HR, cardiac contractility, BP, and myocardial oxygen demand.

• Stable, narrow-complex tachycardias if rhythm remains uncontrolled or unconverted by Adenosine or vagal maneuvers or if SVT is recurrent.
• Controls ventricular rate in PTs with Atrial fibrillation or flutter.
• Certain forms of polymorphic VT (associated with acute ischemia, familial long QT syndrome, catecholinergic)

• Bradycardia
• Asthma
• COPD
• Decompensated CHF

• Due to the risk of bradycardia Atropine should be available.
• In bradycardia refractory to atropine, transcutaneous pacing should be utilized.
• It can precipitate CHF in PTs who are predisposed to the condition and should be used with caution in these PTs.

• Bradycardia.
• Hypotension.
• Lethargy.
• CHF.
• Dyspnea.
• Wheezing.
• Weakness.

IV, IO: 5mg over 5 minutes. It can be repeated at 5mg in 10 minutes if the arrhythmia persists or recurs.

• IV
• IO

Safety and effectiveness has not yet been established

Beta-blocker (Beta-1 selective)

• Decreases heart rate.
• Decreases atrioventricular conduction

• Stable, narrow-complex tachycardias.
• Rate control of Atrial fibrillation or flutter.
• Certain forms of polymorphic VT.

• Sinus Bradycardia.
• Heart block greater than 1st degree.
• Cardiogenic shock.
• Overt CHF.
• Asthma

• Hypotension is common and is usually dose related.
• PTs with CHF may have worsening symptoms.
• May worsen Asthma

• Dizziness.
• Diaphoresis.
• Hypotension.
• Nausea.

Preparation: Place 2.5g ampules in 500cc of D5W, yielding a concentration of 10mg/cc.

Loading dose:500mcg/kg/min for 1 minute then reduce to maintenance dose.

• Maintenance dose: 50mcg/kg/min; if ineffective after 4 minutes, repeat loading dose and increase maintenance dose to 100mcg/kg/min; may repeat as
• needed until a total maintenance dose of 300mcg/kg/min has been achieved.

iv only

100-500mcg/kg/min loading dose over 1 minute, followed by 25-50mcg/kg/min maintenance infusion

Antiarrhythmic (Class II)

• Suppresses ventricular ectopic activity.
• Increases ventricular fibrillation threshold.
• Reduces velocity of electrical impulses through conductive system

Ventricular tachycardia/fibrillation refractory to amiodarone.

• High-degree heart blocks.
• PVCs in conjunction with bradycardia

• Dosage should not exceed 300mg/hr.
• Monitor for CNS toxicity.
• Dosage should be reduced by 50% in PTs older than 70 y/o with liver disease.
• In cardiac arrest, use only in bolus therapy

• Anxiety.
• Drowsiness. 
• Dizziness.
• Confusion.
• N/V.
• Convulsions.
• Widening of QRS complex

• IV bolus,
• IV infusion

1mg/kg

Antiarrhythmic (Class IA)

• Slows conduction through myocardium.
• Elevates ventricular fibrillation threshold.
• Suppresses ventricular ectopic activity

• Ventricular tachycardia with a pulse.
• Pre-existing atrial fibrillation

• High-degree heart blocks.
• PVCs in conjunction with bradycardia

• Dosage should not exceed 17mg/kg.
• Monitor for CNS toxicity

• Anxiety.
• Nausea.
• Convulsions.
• Widening of QRS complex

• Initial: 20mg/min until arrhythmia
• is abolished, hypotension ensues, QRS complex is widened by 50% of original
• width, or total of 17mg/kg has been given.

• Maintenance: 1-4mg/min
• .

• Slow IV bolus,
• IV drip

rarely used