Adenosine

Question 1

What is another name for Adenosine?

Answer 1

Adenocard

Question 2

What drug class is Adenosine in?

Answer 2

endogenous nucleoside

miscellaneous antidysrhythmic

Question 3

How does Adenosine work?

Answer 3

Adenosine slows supraventricular tachycardias by decreasing electrical conduction through the AV node without causing negative inotropic effects.
It also acts directly on sinus pacemaker cells and vagal nerve terminals to decrease chronotropic (heart rate) activity.
It is the first drug choice for most forms of stale, narrow-complex SVT.
Adenosine DOES NOT convert Afib, Aflutter or VT.

Question 4

What is the onset of Adenosine?

Answer 4

immediate

Question 5

What is the duration of Adenosine?

Answer 5

10 seconds

Question 6

What are the indications for Adenosine?

Answer 6

• first choice for most narrow-complex paroxysmal SVT and dysrhythmias associated with bypass tracts such as WPW syndrome
• in undifferentiated, stable wide-complex tachycardia, IV Adenosine may be considered relatively safe. It may convert the rhythm to sinus and may help diagnose the underlying rhythm

Question 7

What are contraindications for Adenosine?

Answer 7

• drug induced tachy
• 2nd or 3rd degree AV block
• Aflutter, Afib, VT, WPW with Afib/flutter

Question 8

What are some adverse reactions of Adenosine?

Answer 8

• transient periods of bradycardia, sinus pause or bradyastole
• ventricular ectopy (VT, Vfib, Vflutter)
• chest pain
• hypotension
• paresthesias
• light-headedness
• metallic taste
• nausea, facial flushing, headache, diaphoresis

Question 9

What are some drug interactions with Adenosine?

Answer 9

• methylxanthines (caffeine, theophylline) antagonize the action of Adenosine
• Diprydamole potentiates the effect of Adenosine; smaller dose may be required
• Carbamazepine may potentiate the AV nodal blocking effect of Adenosine

Question 10

How is Adenosine supplied?

Answer 10

parenteral for IV injection

3mg/mL in 2mL and 5mL vials

Question 11

What is the initial dose of Adenosine?

Answer 11

6mg rapid IV followed by 20mL saline bolus

then elevate extremity

Question 12

What is the second dose of Adenosine?

Answer 12

second dose may be given 1-2 minutes after initial dose

12mg rapid IV bolus followed by 20mL saline bolus

Question 13

What are some special considerations for Adenosine?

Answer 13

• pregnancy safety category C
• brief period of asystole (up to 15 sec) may follow conversion
• reduce initial dose to 3mg in heart transplant patients, patients receiving Dipyridamole or Carbamazepine, or in a central line
• patients taking Theophylline or caffeine may require larger doses
• may cause bronchoconstriction in patients with asthma and in patients with bronchopulmonary disease