Adenosine administration for SVT

Adenosine administration for SVT (adult) should be performed in a monitored setting with ECG monitoring and resuscitation equipment available.

Preparation

• Adenosine is commonly supplied as 6 mg/2 mL (3 mg/mL) or 12 mg/4 mL (3 mg/mL) prefilled syringes.
• Prepare:
  • Adenosine syringe
  • A 20 mL normal saline flush
  • A large-bore IV cannula, preferably in a proximal vein (antecubital fossa).

Administration

1. Confirm the rhythm is a regular narrow-complex SVT and that there are no contraindications.
2. Give 6 mg IV rapid bolus over 1–2 seconds.
3. Immediately follow with a 20 mL normal saline flush given rapidly.
4. Elevate the arm briefly if possible to facilitate delivery to the heart.
5. Monitor the ECG continuously.

If SVT persists

• After 1–2 minutes, give 12 mg IV rapid bolus, followed immediately by a rapid saline flush.
• If still ineffective, a further 12 mg IV rapid bolus may be given according to local protocols.

Important points

• Adenosine has an extremely short half-life (less than 10 seconds), so it must be given rapidly and followed immediately by a saline flush.
• Patients may briefly experience flushing, chest discomfort, shortness of breath, or a feeling of impending doom; these effects are usually short-lived.
• Use caution in patients with severe asthma or certain conduction abnormalities.

Exam-style answer

Drug: Adenosine
Dose: 6 mg rapid IV bolus + 20 mL saline flush; if unsuccessful, 12 mg rapid IV bolus + flush; may repeat 12 mg once.
Route: Rapid IV push through a proximal vein with continuous ECG monitoring.

Always follow your local ACLS, hospital, or national guidelines, as protocols may vary.