Adenosine

Question 1

What class of medication is adenosine?

Answer 1

Antiarrhythmtic

Question 2

What is the mechanism of action of adenosine?

Answer 2

G-couple protein adenosine A1 receptor

Question 3

How does adenosine work?

Answer 3

Transiently slows conduction through the AV node by inhibiting adenylyl cyclase enzymes
- reduces production of cAMP
- causes efflux of potassium
- heart becomes hyperpolarised
- slows the rate of rise of pacemaker potential

Question 4

What are the indications for adenosine?

Answer 4

Reversion to sinus rhythm in supraventricular tachycardia
(emergency management)

Question 5

What are the contraindications for adenosine?

Answer 5

Second and third degree heart block
Severe hypotension
Decompensated heart failure
COPD
Asthma
Long QT syndrome
Sick sinus syndrome

Question 6

What are the common side effects of adenosine?

Answer 6

Chest discomfort/pain
Nausea
Dyspnoea
Arrhthymias
AV block

Question 7

What are the interactions of adenosine?

Answer 7

Theophylline - blocks adenosine receptors
Dipyridamole - blocks uptake of adenosine for degradation and prolongs adverse effects

Question 8

How is adenosine given?

Answer 8

Adenosine is given over 2 seconds into a central or large peripheral vein, surrounded by 0.9% sodium chloride