Adenosine

Indications

Adenosine is used for: Paroxysmal supraventricular tachycardia, Supraventricular tachycardia

Adult Dose

Intravenous Differential diagnosis of supraventricular tachycardias Adult: Initially, 3 mg by rapid IV inj into a central or large peripheral vein over 2 sec with cardiac monitoring; 6 mg may be given after 1-2 minutes if necessary, then 12 mg after a further 1-2 minutes. Avoid increments if high level AV block occurs at any particular dose. Paroxysmal supraventricular tachycardia Adult: Initially, 3 mg by rapid IV inj into a central or large peripheral vein over 2 sec with cardiac monitoring; 6 mg may be given after 1-2 minutes if necessary, then 12 mg after a further 1-2 minutes. Avoid increments if high level AV block occurs at any particular dose. Myocardial imaging Adult: 140 mcg/kg/minute by infusion for 6 minutes. Inject radionuclide 3 minute after infusion.

Child Dose

Intravenous Differential diagnosis of supraventricular tachycardias Child: Initially, 50-100 mcg/kg; if necessary, may increase dose by 50-100 mcg/kg increments at 1-2 minute intervals or until arrhythmia is controlled. Max dose: 300 mcg/kg. Paroxysmal supraventricular tachycardia Child: Initially, 50-100 mcg/kg; if necessary, may increase dose by 50-100 mcg/kg increments at 1-2 minute intervals or until arrhythmia is controlled. Max dose: 300 mcg/kg. Myocardial imaging Adult: 140 mcg/kg/minute by infusion for 6 minutes. Inject radionuclide 3 minute after infusion.

Renal Dose

Administration

IV Administration Adenocard: given as a rapid injection (1-3 sec) by peripheral IV route directly into vein or into IV line close (proximal) to patient & is followed by rapid NS flush after each inj (20 mL for adults, 5 mL or more for peds) Place pt in mild reverse Trendelenburg position before giving drug.

Contra Indications

Hypersensitivity 2nd or 3rd degree AV block (except those on pacemakers) Sinus node disease, such as sick sinus syndrome or symptomatic bradycardia (except in patients with a functioning artificial pacemaker) Adenosine: Contraindicated in bronchoconstrictive or bronchospastic lung disease (eg, asthma)

Precautions

Cardiac Arrest, Ventricular Arrhythmias, and Myocardial Infarction. Fatal cardiac events have occurred. Avoid use in patients with symptoms or signs of acute myocardial ischemia. Appropriate resuscitative measures should be available. Sinoatrial (SA) and Atrioventricular (AV) Nodal Block. First-, second- or third-degree AV block, or sinus bradycardia can occur. Discontinue Adenosine if the patient develops persistent or symptomatic high-grade. AV block Bronchoconstriction. Can induce dyspnea, bronchoconstriction, and respiratory compromise, especially in patients with obstructive pulmonary disease. Discontinue Adenosine if the patient develops severe respiratory difficulties. Hypotension. Significant hypotension can occur. Discontinue Adenosine if the patient develops persistent or symptomatic hypotension. Cerebrovascular Accidents. Hemorrhagic and ischemic cerebrovascular accidents have occurred. Seizures. New onset or recurrence of convulsive seizures have occurred. The use of methylxanthines (e.g., caffeine, aminophylline and theophylline) is not recommended in patients who experience a seizure in association with Adenoscan Hypersensitivity. Dyspnea, throat tightness, flushing, erythema, rash, and chest discomfort have occurred. Have personnel and resuscitative equipment immediately available. Atrial Fibrillation. Reported in patients with or without a history of atrial fibrillation. Hypertension. Clinically significant increases in systolic and diastolic pressure have been observed. Monitoring Parameters Monitor ECG and have resuscitation facilities available.

Pregnancy-Lactation

Pregnancy Category: C Lactation: Potential for serious adverse reactions in nursing infants; decision to interrupt nursing after administration of adenosine or not should take into account importance of drug to mother

Interactions

Adenosine effects antagonised by methylxanthines like caffeine, theophylline, etc. Concomitant carbamazepine may increase the risk of heart block. Contraindicated (0) Serious - Use Alternative (1) ponesimod Potentially Fatal: Adenosine effects are potentiated by dipyridamole.

Adverse Effects

Side effects of Adenosine : >10% Flushing (18%),Dyspnea (12%) 1-10% Chest pain (7%),HA (2%),Lightheadedness (2%),Dizziness (1%),Tingling in arms (1%),Numbness (1%),Nausea (3%) <1% Hypotension,Palpitations,Apprehension,Head pressure,Chest pain,Hyperventilation,Blurred vision,Burning sensation,Heaviness in arms, neck & back pain,Metallic taste,Tightness in throat,Pressure in groin,Sweating

Mechanism of Action

Adenosine acts rapidly to slow down conduction through the AV node via the A1 receptors. It also mediates peripheral and coronary vasodilatation by stimulating the A2 receptors. Extremely short plasma half-life (<10 sec) permits dosage titration during IV use every 1-2 min and causes no concern of cumulative effect through repeated dosing.