Adenosine ออกออกฤทธิ์อย่างไร มีข้อบ่งชี้อย่างไร มีเทคนิคการใช้อย่างไร
Mechanism of action/Effect:-Slows impulse formation in the sinoatrial (SA) node, slows conduction time through the atrioventricular (AV) node, and can interrupt reentry pathways through the AV node.
-Depresses left ventricular function, but because of its short half-life, the effect is transient, allowing use in patients with existing poor left ventricular function
-Conversion to sinus rhythm of paroxysmal supraventricular tachycardia (PSVT), including that associated with accessory bypass tracts (Wolff-Parkinson-White Syndrome). When clinically advisable, appropriate vagal maneuvers (e.g., Valsalva maneuver), should be attempted prior to Adenocard administration.
-Not convert atrial flutter, atrial fibrillation, or ventricular tachycardia to normal sinus rhythm. In the presence of atrial flutter or atrial fibrillation, a transient modest slowing of ventricular response may occur immediately following Adenocard administration.
Administation:-The dose recommendation is based on clinical studies with peripheral venous bolus dosing. Central venous (CVP or other) administration of Adenocard has not been systematically studied.
The recommended intravenous doses for adults are as follows:
-Initial dose: 6 mg given as a rapid intravenous bolus (administered over a 1-2 second period).
-Repeat administration: If the first dose does not result in elimination of the supraventricular tachycardia within 1-2 minutes, 12 mg should be given as a rapid intravenous bolus. This 12 mg dose may be repeated a second time if required.
Mechanism of Action : Slows conduction time through the AV node, interrupting the re-entry pathways through the AV node, restoring normal sinus rhythmตอบลบ
Paroxysmal supraventricular tachycardia (Adenocard®): I.V. (rapid, over 1-2 seconds, via peripheral line): Initial: 6 mg; if not effective within 1-2 minutes, 12 mg may be given; may repeat 12 mg bolus if needed (maximum single dose: 12 mg). Follow each dose with normal saline flush.
Recommended dosage adjustment for adenosine when administered via central line or with concurrent carbamazepine or dipyridamole (ACLS, 2005): Initial dose: 3 mg
Pharmacologic stress testing (Adenoscan®): I.V.: Continuous I.V. infusion via peripheral line: 140 mcg/kg/minute for 6 minutes using syringe or columetric infusion pump; total dose: 0.84 mg/kg. Thallium-201 is injected at midpoint (3 minutes) of infusion.
Acute vasodilator testing in pulmonary artery hypertension (unlabeled use) (Adenoscan®): I.V.: Initial: 50 mcg/kg/minute increased by 50 mcg/kg/minute every 2 minutes to a maximum dose of 500 mcg/kg/minute (Schrader, 1992) or to a maximum dose of 250 mcg/kg/minute (McLaughlin, 2009); acutely assess vasodilator response
(For additional information see "Adenosine: Pediatric drug information")
Rapid I.V. push (over 1-2 seconds) via peripheral line:
Paroxysmal supraventricular tachycardia (Adenocard®): Infants and Children:
Children <50 kg: Initial: 0.05-0.1 mg/kg (maximum initial dose: 6 mg). If conversion of PSVT does not occur within 1-2 minutes, may increase dose by 0.05-0.1 mg/kg. May repeat until sinus rhythm is established or to a maximum single dose of 0.3 mg/kg or 12 mg. Follow each dose with normal saline flush.
Children ≥50 kg: Refer to adult dosing.
Pediatric advanced life support (PALS, 2005): Treatment of SVT: I.V., I.O.: Initial: 0.1 mg/kg (maximum initial dose: 6 mg); if not effective within 1-2 minutes, administer 0.2 mg/kg; may repeat 0.2 mg/kg if needed (maximum single dose: 12 mg). Follow each dose with normal saline flush.
FDA-Labeled Indications :ตอบลบ
- Cardiac thallium 201 study; Adjunct
- Paroxysmal supraventricular tachycardia
Non-FDA Labeled Indications
- Advanced cardiac life support - Supraventricular tachycardia
- Coronary artery bypass graft
- Myocardial imaging, Technetium-99M
- Percutaneous transluminal angioplasty
- Stress echocardiography
- Supraventricular arrhythmia; Diagnosis