Dosing and uses of Adenocard, Adenoscan (adenosine)
Adult dosage forms and strengths
injectable solution
- 3mg/mL
Paroxysmal Supraventricular Tachycardia
Indicated for conversion to sinus rhythm of paroxysmal supraventricular tachycardia (PSVT), including that associated with accessory bypass tracts (Wolff-Parkinson-White Syndrome)
Adenocard: 6 mg IVP over 1-3 seconds (maybe given IO) followed by rapid flush with 20 mL NS, if no conversion within 1-2 minutes give 12 mg IVP, repeat a second time if necessary (30 mg total)
Dosing considerations
- When clinically advisable for PSVT, appropriate vagal maneuvers (eg, Valsalva maneuver), should be attempted prior to adenosine administration
Stress Testing (Diagnostic)
Indicated as an adjunct to thallium-201 myocardial perfusion scintigraphy in patients unable to exercise adequately
Adenoscan: 140 mcg/kg/min IV infusion for 6 min
Other Indications & Uses
Off-label: Sustained ventricular tachycardia (SVT)
Pediatric dosage forms and strengths
injectable solution
- 3mg/mL
Paroxysmal Superventricular Tachycardia (per ACLS)
<50 kg: 0.05 to 0.1 mg/kg rapid IVP over 1-3 seconds or IO, no more than 0.3 mg/kg/dose, followed by rapid flush with > 5 mL 0.9% NaCL
If necessary may give 2nd dose of 0.2 mg/kg IVP/IO, not to exceed cumulative dose of 12 mg
Geriatric dosage forms and strengths
Elderly may experience more adverse effects from adenosine; they may be more sensitive
PSVT (Adenocard)
6 mg IVP over 1-3 seconds (maybe given IO) followed by rapid flush with 20 mL NS, if no conversion within 1-2 minutes give 12 mg IVP, repeat a second time if necessary (30 mg total)
Adenoscan (Diagnostic)
Stress testing (Adenoscan): 140 mcg/kg/min IV infusion for 6 min
Adenocard, Adenoscan (adenosine) adverse (side) effects
>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
Post Marketing (undefined)
Prolonged asystole
Ventricular tachycardia
Venricular fibrillation
Transient increase in blood pressure
Bradycardia
Atrial fibrillation
Cardiac failure
Infusion site pain
Hypersensitivity
Torsades de Pointes
Seizure
Bronchospasm
Warnings
Contraindications
Hypersensitivity
2nd or 3rd degree AV block (except those on pacemakers), sick sinus syndrome, atrial flutter or fib, V-tach
Adenoscan: Contraindicated in bronchoconstrictive or bronchospastic lung disease (eg, asthma)
Cautions
Symptomatic bradycardia, cardiac arrest, heart block, heart transplant patients, HTN, hypotension, MI, proarrhythmic events, unstable angina
Adenocard: Caution with bronchoconstrictive or bronchospastic lung disease (eg, asthma)
Cerebrovascular accident hemorrhagic and ischemic cerebrovascular accidents reported; hemodynamic effects of adenosine including hypotension or hypertension possibly associated with these adverse reactions
Nucleoside transport inhibitors (eg, dipyridamole) and potentiate the vasoactive effects of adenosine; withhold for 5 half-lives before adenosine administration
Methylxanthines (eg, caffeine, theophylline) are adenosine receptor antagonists and inhibit adenosine’s vasoactive effects; withhold methylxanthines for 5 half-lives before adenosine administration
New-onset or recurrence of convulsive seizures reported following adenosine; some seizures are prolonged and require emergent anticonvulsive management; aminophylline may increase risk of seizures associated with adenosine; methylxanthine use not recommended in patients who experience seizures in association with adenosine administration
Dyspnea, throat tightness, flushing, erythema, rash, and chest discomfort reported that may require symptomatic treatment; resuscitative measures may be necessary if symptoms progress; have trained personnel and treatment available during treatment
Arrhythmia at time of cardioversion (Adenocard): Ventricular fibrillation reported following administration, including both resuscitated and fatal events; in most instances, these cases were associated with the concomitant use of digoxin and, less frequently with digoxin and verapamiL
Risk for myocardial infarction and death
- Avoid use for cardiac nuclear stress tests in patients with signs or symptoms of acute myocardial ischemia (eg, unstable angina, cardiovascular instability); use may increase risk of fatal MI
- Screen all nuclear stress test candidates for risks
Pregnancy and 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
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Adenocard, Adenoscan (adenosine)
Mechanism of action
PSVT: Slows conduction through AV node and interrupts AV reentry pathways, which restore normal sinus symptoms
Stress testing: A2A adenosine receptor agonist; activation of the A2A adenosine receptor produces coronary vasodilation and increases coronary blood flow
Pharmacokinetics
Half-Life: <10 sec
Duration: <10 sec
Onset: 20-30 sec
Metabolism: Blood & tissue; deaminated to inosine & subsequently to hypoxanthine; adenosine also undergoes phosphorylation to adenosine monophosphate (AMP) within blood cells
Metabolites: inosine, hypoxanthine, AMP (inactive)
Total Body Clearance: 30 sec
Administration
IV Compatibilities
Solution: dextrose 5% in LR, D5W, LR, Ns
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
Record rhythm strip during administration
Draw up (separate syringes)
- Adenosine dose
- Flush
- Attach BOTH syringes to IV injection port nearest to patient
Clamp IV tubing above injection port
Avoid drug traveling retrograde
Push adenosine AS FAST AS POSSIBLE (1-3 sec)
WHILE KEEPING PRESSURE ON ADENOSINE SYRINGE PLUNGER, push NS flush as fast as possible
Unclamp IV tubing
Preferred method using a stopcock
- Have Adenosine in one port & NS flush in other port
- Simply open stopcock to Adenosine & push
- Close stopcock & open port to NS & push Eliminates possibility of Adenosine traveling retrograde
May be given via central line or intraosseus
Adenoscan: given by continuous peripheral IV infusion for 6 min
Storage
Store at controlled room temperature of 15-30°C
Do not refrigerate; possible crystal formation
Solution must be clear prior to administration
