Adenosine

Question 1

Class

Answer 1

1. Supraventricular Antiarrythmic

2. Endogenous nucleoside (occurs naturally in all cells of the body)

Question 2

Trade name

Answer 2

Adenocard

Question 3

Actions

Answer 3

Slows tachycardias associated with the AV node via modulation of the autonomic nervous system w/o causing negative inotropic effects. It acts directly on sinus pacemaker cells and vagal nerve terminals to decrease chronotropic and domotropic activity. Thus it…

1. Slows conduction through the AV node
2. Blocks reentry pathways through the AV node
3. Can slow conduction in the SA node somewhat

Question 4

Indications

Answer 4

1. PSVT (including WPW) refractory to vagal maneuvers

2. Stable regular monomorphic wide complex tachycardia

Question 5

Contraindications

Answer 5

1. 2nd or 3rd degree heart block (w/o a functioning pacemaker
2. Sick sinus syndrome
3. Known hypersensitivity
4. Pregnant (C)
5. Known atrial fibrillation or atrial flutter (not effective in managing these arrhythmias)
6. Irregular wide-complex tachycardias
7. May cause refractory bronchospasm. Use w/ caution w/ COPD and asthma

Question 6

Dosage

ADULTS

Answer 6

6mg rapid IV bolus followed by 20mL flush

   - No response in 1-2 min -- 12mg
   - Follow each dose w/ a flush of at least 20mL

Question 7

Dosage

PEDIATRICS

Answer 7

0. 1mg/kg rapid IVP (MAX first dose 6mg)
   - –>if no effect, 0.2mg/kg (MAX single dose 12mg)
   - MAX total dose 18mg
   - Follow each dose w/ a flush of at least 20mL

Question 8

Why does adenosine require a rapid push? And where?

Answer 8

Extremely short half-life. Should be given as proximal to the heart as possible.

Question 9

Onset

Answer 9

30 seconds or less

Question 10

Duration

Answer 10

10 seconds

Question 11

Side Effects

Answer 11

1. flushing 2. chest pain 3. dyspnea 4. headache 5. diaphoresis 6. metallic taste 7. dizzy 8. lightheadedness 9. numbness 10. N/V 11. palpitations

Question 12

Interactions

ADDITIVE EFFECTS

Answer 12

digoxin, calcium channel blockers

Question 13

Interactions

ANTAGONISTIC EFFECTS

Answer 13

methylxanthines (caffeine, theophylline)

Question 14

Interactions

POTENTIATING EFFECTS

Answer 14

dipyridamole (persantine)