For the stable patient, adenosine should be used within the tachycardia algorithm when vagal maneuvers fail to terminate stable narrow-complex SVT. For the unstable patient with a regular and narrow QRS complex, adenosine may be considered prior to synchronized cardioversion.
Adenosine is the primary drug used in the treatment of stable narrow-complex SVT (supraventricular Tachycardia). It can now also be used for regular monomorphic wide-complex tachycardia.
When given as a rapid IV bolus, adenosine slows cardiac conduction particularly affecting 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.
Dosing
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.
A lower initial dose of 3mg should be used for patients taking dipyridamole or carbamazepine as these two medications potentiate the effects of adenosine.
Also, prolonged asystole has been seen with the use of normal doses of adenosine in heart transplant patients and central line use. Therefore, the lower dose (3mg) may be considered for patients with a central venous line or a history of heart transplant.
Precautions
Some side effects of adenosine administration include flushing, chest pain/tightness, brief asystole or bradycardia.
Make sure that adenosine is not used for irregular, polymorphic wide-complex tachycardia and unstable VT. Use in these cases may cause clinical deterioration.
Rainer says
What about intravenous ATP infusions over prolonged time? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2039853/
When given too quickly, will they lead to cardiac arrest invariably? At which rate will they lead to cardiac arrest?
Jeff with admin. says
The study referenced has nothing to do with adenosine used within the framework of ACLS. Adenosine and its use within ACLS is limited to very rapid IV push of 6 mg and 12 mg doses. The rapid IV push of adenosine does cause a temporary (arrest) cessation of the electrical impulse of the heart. Adenosine is metabolized very rapidly by every cell in the body. For adenosine to cause arrest is must be a very rapid IV bolus and the dose would have to be extremely high. An infusion is not likely to cause cardiac arrest or even significant symptoms as the study suggests.
Kind regards,
Jeff
Shahram Bayanati says
Does Adenosine use in polymorphic SVT as well?
Jeff with admin. says
I have not ever heard of polymorphic SVT??
Do you mean polymorphic VT? If this is what you mean then the answer would be no you would not use adenosine for polymorphic VT because the rate is not regular.
SVT is typically caused by an accessory pathway in the heart and will have a regular rate that is generated by the ventricles. If you see an SVT like rhythm that is irregular, you should assume atrial fibrillation and adenosine is contraindicated for atrial fibrillation.
Studies in the literature report serious rhythm degeneration and even death when adenosine has been inadvertently given to patients with either atrial fibrillation or atrial flutter.
Ref:
Mallet ML. Proarrhythmic effects of adenosine: A review of the literature. Emerg Med J. 2004;21(4): 408–410.
Exner DV, Muzyka T, & Gillis AM. Proarrhythmia in patients with the Wolff-Parkinson-White syndrome after standard doses of intravenous adenosine. Ann Int Med. 1995;122(5):351–352.
12. Haynes BE. Two deaths after prehospital use of adenosine. J Emerg Med. 2001;21(2):151–154.
Shah CP, Gupta AK, Thakur RK, et al. Adenosine-induced ventricular fibrillation. Indian Heart Journal, 2001;53(2):208–210.
Kind regards,
Jeff
Liz says
No such thing as polymorphic SVT. Very important to know your cardiac rhythms if thinking about giving a medication affecting the heart!!!
Linds says
Shaming someone for asking questions is a bad way to ensure they continue to ask them. Especially when they’re critical questions about the heart. But I’m glad you’re talking your responsibility to educate this person so seriously, hopefully you haven’t done irreparable damage. Because the next time they’re unsure about something they might.
Dr.hasan says
Please remember that we have all been in the same shoes initially…a person is a learner till death..there are better ways to address and be contributory to someone’s knowledge