ACLS and Adenosine:
Adenosine should be used within the tachycardia algorithm when vagal maneuvers fail to terminate stable narrow-complex SVT.
When given as a rapid IV bolus, adenosine slows cardiac conduction particularly effecting conduction through the AV node. The rapid bolus of adenosine also interrupts reentry (SVT causing) pathways through the AV node and restores sinus rhythm in patients with SVT.
When injected into the body, adenosine is rapidly absorbed by red blood cells and blood vessel endothelial cells and metabolized for natural uses throughout the body. In light of this adenosine should be administered by RAPID intravenous bolus so that a significant bolus of adenosine reaches the heart before it is metabolized.
A change from the 2010 guidelines now has adenosine given up to two times rather than three.
The first dose of adenosine should be 6 mg administered rapidly over 1-3 seconds followed by a 20 ml NS bolus. If the patient’s rhythm does not convert out of SVT within 1 to 2 minutes, a second 12 mg dose may be given in similar fashion. All efforts should be made to administer adenosine as quickly as possible.
Some side effects of adenosine administration incude flushing, chest pain/tightness, brief asystole or bradycardia.
Make sure that adenosine is not used for irregular, polymorphic wide-complex tachycardia or VT. Use in these cases may cause clinical deterioration.