What are the effects of adenosine given as a fast intravenous (IV) push?

From the Guidelines

Adenosine given as a fast intravenous (IV) push is effective in terminating supraventricular tachycardia (SVT) and has a rapid onset of action, but it can also cause transient side effects such as flushing, dyspnea, and chest discomfort.

Key Effects of Adenosine

• The initial dose of adenosine is 6 mg given as a rapid IV push, followed by a 20 mL saline flush 1.
• If the rhythm does not convert within 1 to 2 minutes, a second dose of 12 mg can be administered 1.
• Adenosine is safe and effective in pregnancy, but it should not be given to patients with asthma 1.
• The drug has several important drug interactions, including larger doses required for patients with significant blood levels of theophylline, caffeine, or theobromine, and reduced initial dose to 3 mg in patients taking dipyridamole or carbamazepine 1.

Side Effects and Precautions

• Common side effects of adenosine include flushing, dyspnea, and chest discomfort, which are usually transient 1.
• Adenosine can also cause bronchospasm in asthmatic patients and should be used with caution in these patients 1.
• The drug can precipitate atrial fibrillation with rapid ventricular rates in patients with Wolff-Parkinson-White (WPW) syndrome, and a defibrillator should be available when adenosine is administered to these patients 1.

Clinical Use

• Adenosine is the drug of choice for terminating AV nodal re-entrant tachyarrhythmias 1.
• It can be used in combination with β blockers and does not cause depression of myocardial contractility 1.
• Adenosine should be given in a monitored environment, such as a critical care unit or accident and emergency department, due to the risk of transient complete heart block 1.

From the FDA Drug Label

Adenosine produces a direct negative chronotropic, dromotropic and inotropic effect on the heart, presumably due to A1-receptor agonism, and produces peripheral vasodilation, presumably due to A2-receptor agonism The net effect of adenosine injection in humans is typically a mild to moderate reduction in systolic, diastolic and mean arterial blood pressure associated with a reflex increase in heart rate. Rarely, significant hypotension and tachycardia have been observed [see Warnings and Precautions ( 5-5.4)].

The effects of adenosine given as a fast intravenous (IV) push are:

• Negative chronotropic, dromotropic, and inotropic effects on the heart
• Peripheral vasodilation
• Typically a mild to moderate reduction in blood pressure with a reflex increase in heart rate
• Rarely, significant hypotension and tachycardia may occur 2 Key adverse reactions include:
• Flushing
• Chest discomfort
• Shortness of breath
• Headache
• Dizziness 2

From the Research

Effects of Adenosine Given as a Fast Intravenous (IV) Push

• The administration of adenosine as a fast IV push has been studied in various contexts, including the treatment of paroxysmal supraventricular tachycardia (PSVT) 3, 4.
• In the context of PSVT, adenosine given as a fast IV push has been shown to be effective in converting patients to sinus rhythm, with success rates ranging from 85% to 88% 3, 4.
• The use of adenosine in this context is also considered safe, with side effects being infrequent, mild, and transient 3, 4.
• However, the dose of adenosine required may vary depending on the individual patient and the specific circumstances, with some studies suggesting that lower doses may be effective in certain cases 5.
• In terms of the effects of adenosine on hemodynamics, studies have shown that it can cause changes in heart rate and blood pressure, although these effects are typically short-lived and well-tolerated 6, 7.
• The comparison of intravenous and intracoronary administration of adenosine has also been studied, with some research suggesting that high-dose intracoronary adenosine may be equivalent to or even more effective than intravenous administration in achieving maximum hyperemia 7.