Adenosine administration for neonatal SVT.

Adenosine is a purine nucleoside that impairs conduction through the AV node and is thus effective in terminating tachycardias involving the AV node. Gaining acceptance as the drug of choice for neonatal supraventricular tachycardia (SVT), it is given IV as a rapid bolus with an initial dose of 0.05 mg/kg and can be increased in increments of 0.05 mg/kg every one to two minutes until termination of SVT (to a maximum of 0.25 mg/kg). Because of its half-life of 0.6 to 10 seconds, adenosine will not prevent reinitiation of SVT, therefore other medications should be considered if prophylaxis is required. An advantage of the short half-life is the transient nature of adverse effects, which can include flushing, nondistressing alterations in respiratory pattern, irritability, sinus bradycardia, and varying degrees of AV block. Administration to critically ill infants, including those requiring mechanical ventilation, has been reported. The infant's blood pressure, electrocardiogram, respiratory status, and capillary refill should be monitored before, during, and after adenosine administration.