Adenosine (Adenocard)

Question 1

Drug Class

Answer 1

Antidysrhythmic

Question 2

Mechanism of Action

Answer 2

Short acting drug that slows conduction through the AV node, can restore sinus rhythm in patients with SVT and terminate regular tachycardias casued by reentrant AV nodal pathways

Question 3

Indications and Contraindications

Answer 3

Indications: Stable, regular, narrow-complex SVT, including those involving AV nodal reentry. Consider for unstable narrow-complex reentry tachycardia while preparing for cardioversion. Can be used diagnostically for stable, regular, monomorphic wide-complex tachycardia

Contraindications: Second or third degree AV block or sick sinus syndrome unless functional pacemaker present, poison or drug induced tachycardia. Caution with patients w/ history of seizure disorder. May induce bronchospasm in patients with asthma. Brief period of dysrhythmia, including asystole, may occur during pharmacologic conversion

Question 4

Side Effects & Interactions

Answer 4

Effects: Transient and of short duration: Sweating, dizziness, nervousness, paresthsia, hypotension, doom, severe bronchospasm. Period of dysrhythmia or asystole.

Interactions: Additive effects if used with beta blockers. Methylxanthines block the actions of adenosine. Dipyridamole (Persantine) potentiates the effect of adenosine. Carbamazepine (Tegretol) may potentiate the AV node blocking effect of adenosine. Nicotine can enhance cardiovascular effects; an increase in angina-like discomfort or heart rate, decrease in BP may be observed

Question 5

Dosage and Administration

Answer 5

Adult: Give a 6mg rapid IV/IO bolus over 1-3s, follow with 10mL saline flush. If no conversion after 1-2min, administer 12mg rapidly. May repeat 12mg dose once if no conversion after 1-2min. Max total dose 30mg, reduce dosage by half in patients taking dipyridamole or carbamazepine or in those with transplanted hearts or if given through central IV

Pediatric: Initial dose 0.1mg/kg rapid IV/IO push over 1-3 seconds (max first dose 6mg), followed by 5-10mL saline flush. Second dose 0.2mg/kg rapid IV/IO push (max dose 12mg) followed by 5-10mL flush

Question 6

Duration of Action

Answer 6

Onset: seconds, Peak: seconds, Duration: 10 seconds

Question 7

Special Considerations

Answer 7

Pregnancy Category C, Ineffective in converting AF, atrial flutter or VT. Should not be administered for hemodynamically unstable, irregularly irregular, or polymorphic wide-complex tachycardias