ACLS: Tachycardia

3 questions

1. Is the pt in a sinus rhythm?
2. Is the QRS wide or narrow?
3. Is the rhythm regular or irregular?

Narrow Regular

1. See also Tachycardia (Narrow)
2. Sinus Tachycardia
   1. Treat underlying cause
3. SVT
   1. Vagal maneuvers (convert up to 25%)
   2. Adenosine 6mg IVP (can follow with 12mg if initially fails)
      1. If adenosine fails initiate rate control with CCB or BB
         1. Diltiazem 15-20mg IV, followed by infusion of 5-15mg/hr
         2. Metoprolol 5mg IVP x 3 followed by 50mg PO
   3. Synchronized Cardioversion (50-100J)

Narrow Irregular

1. MAT
   1. Treat underlying cause (hypoK, hypomag)
2. Sinus Tachycardia w/ frequent PACs
3. A fib / A Flutter w/ variable conduction
   1. Rate control with:
      1. Dilt
      2. MTP (good in setting of ACS)
      3. Amiodarone (good in setting of hypotension, CHF)
      4. Digoxin (good in setting of CHF)
   2. Synchronized Cardioversion (120-200 J)

Wide Regular

• If unstable: shock (synchronized 100J)
  • Hhypotension, AMS, shock, ischemic chest discomfort, acute heart failure)
• If stable:
  • Meds
    • Procainamide
      • 20-50mg/min; then maintenance infusion of 1mg/min x6hr
      • Tx until arrhythmia suppressed, QRS duration increases >50%, hypotension, 17m/kg given
      • Avoid if prolonged QT or CHF
    • Amiodarone
      • 150mg over 10min (repeat as needed); then maintenance infusion of 1mg/min x6hr
    • Adenosine
      • May be considered for diagnosis and treatment only if rhythm is regular and monomorphic
  • Synchronized cardioversion (100J)

Wide Irregular

• DO NOT use AV nodal blockers
  • Can precipitate V-Fib

1. A fib w/ preexcitation
   1. 1st line - Electric cardioversion
   2. 2nd line - Procainamide, amiodarone, or sotalol
2. A fib w/ aberrancy
3. Polymorphic V-Tach / Torsades
   1. Emergent defibrillation (NOT synchronized)
   2. Correct electrolyte abnormalities
      1. HypoK, hypoMag
   3. Stop prolonged QT meds

See Also

• ACLS (Main)
• Tachycardia (Wide)
• Tachycardia (Narrow)