Tuesday Advanced Cases & Procedure Pearls

From the Archives: Approach to Refractory SVT by Dr. Richard Byrne (featuring Dr. Eric Hasbun)

Step 1: Modified Valsalva

  • Have the patient lie in a semi-recumbent position and blow into a standard 10 mL syringe as long as they can.
  • Lay the patient supine and elevate the lower extremities for 1 minute.
Enjoy this demo from the 2019 ResusEM conference with Cooper EM graduate Eric Hasbun (who apparently needs to work on his core)

Step 2: Escalating adenosine doses

  • If standard dose of 6 mg of IV adenosine fails to terminate SVT, escalate subsequent doses by 6 mg.
  • Doses up to 36 mg has been successful in case reports.

Step 3: Attempt an infusion of a Calcium Channel Blocker

  • Diltiazem or verapamil can be given as a slow bolus.
    • Has been shown to be at least as successful, if not more successful, than adenosine in terminating SVT
    • May cause hypotension – treat with fluids and/or IV calcium gluconate

Step 4: If cardioverting, use propofol as sedative

  • Propofol has terminated a variety of tachyarrhythmias in multiple case series.
  • Remember to administer pain medication as propofol has no analgesic effects.
  • Synchronized cardioversion of SVT only requires 50 Joules as initial dose.

References:
Lim SH, Anantharaman V, Teo WS, Chan YH. Slow infusion of calcium channel blockers compared with intravenous adenosine in the emergency treatment of supraventricular tachycardia. Resuscitation 2009; 80:523-528.

Bailey AM, Baum RA, Rose J, Humphries RL. High-Dose Adenosine for Treatment of Refractory Supraventricular Tachycardia in an Emergency Department of an Academic Medical Center: A Case Report and Literature Review. J Emerg Med. 2016 Mar;50(3):477-81.

Appelboam A, Mann C, et al. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet 2015; 386:1747-53

Leave a Reply

Your email address will not be published. Required fields are marked *