Tachycardia; Stable Wide Complex Regular

1. Evaluate ABC's
   • Confirm stability, pulses, adequate blood pressure, good skin signs and mentation to proceed with this algorithm.
2. Early measures:
   • Apply oxygen
   • Make sure defibrillator present (in case stability changes)
   • Establish IV
   • Monitors (Rhythm, Oximetry, BP)
   • Obtain 12 lead EKG and confirm QRS >0.12 sec
   • Code cart
3. Obtain history and perform physical examination and consider causes:
   • Differential diagnosis includes:
   • Ventricular tachycardia (VT) monomorphic
   • SVT with aberrancy
   • Pre-excited tachycardias with accessory pathway
   • Consider Causes
   • Acute myocardial infarction, pulmonary embolus
   • Hypovolemia/Hypoxia/Hypothermia
   • Metabolic: Thyroid disease, hyper/hypokalemia, hypercalcemia, acidosis
   • Hpoglycemia
   • Drugs: Cocaine, Amphetamines, Decongestants, Ephedra, Ginseng
   • Pneumothorax or Tamponade
   • Cardiomyopathy/Valvular heart disease
   • Alcohol related ("Holiday heart")
   • Sepsis/Pneumonia
4. 1. Treatment for Monomorphic VT:
      • Amiodarone: 150 mg IV over 10 minutes then 1 mg/minute infusion × 6 hours then 0.5 mg/minute × 18 hours.
      • May use procainamide or sotalol instead of amiodarone
      • Anticipate deterioration and need to switch to unstable wide complex tachycardia algorithm
   2. Treatment for SVT w/ aberrancy:
      • Initial Treatment
      • Vagal stimulation (Unilateral carotid massage &/or valsalva) or Adenosine
      • Adenosine 6 mg rapid IVP immediately followed by 20 mL NS IVP. If ineffective, may repeat × 2 at 1-2 minute intervals with 12 mg/dose using same technique.
      • Adenosine dose to be reduced to 50% of that listed above if central line, carbamazepine (Tegretol) or dipyridamole (Persantine) use.
      • If rhythm converts to NSR, is likely SVT.
      • If converts to NSR
      • Observe for recurrence
      • If recurs treat with adenosine, calcium channel blocker or beta blocker (dosing listed below)
      • If doesn't convert to NSR
      • Choose 1 of the following (dosing listed below):
      • CCB's: Diltiazem or verapamil
      • Beta Blockers: Metoprolol, atenolol, esmolol, propranolol

      Note: Avoid beta blockers in patients with CHF or pulmonary disease

      Diltiazem:0.25 mg/kg [Max 20 mg] IV over 2 minutes; may repeat with 0.35 mg/kg [Max 25 mg] IV in 15 minutes. May start infusion 5-15 mg/hr after either bolus.
      Verapamil:2.5-5 mg IV over 2 minutes; may repeat with 5-10 mg IV in 15-30 minutes until maximum cumulative dose of 20 mg given if needed.
      Metoprolol:5 mg given slow IV every 5 minutes × 3 doses. Typically follow this with 50 mg PO after last IV dose.
      Atenolol:5 mg slow IV, may repeat in 10 minutes. Typically follow this with 50 mg PO after last IV dose.
      Esmolol:Loading dose of 500 mcg/kg given over 1 minute then 50 mcg/kg/minute × 4 minutes. If inadequate response, reload with 500 mcg/kg given over 1 minute and follow this with an increased rate of infusion of 100 mcg/kg/minute and adjust as needed (maximum rate is 300 mcg/kg/minute).
      Propranolol:0.1 mg/kg divided into 3 equal doses, each given IV at 2-3 minute intervals. May repeat the total dose × 1 if not successful.
5. Standard laboratory evaluation (if indicated):
   • CBC, Electrolytes, TSH, Cardiac enzymes and toxicology testing
   • CXR
   • EKG pre and post conversion (if conversion occurs)
6. Consultation and admission to hospital if indicated.

Source: Circulation 2005;112. 2005 AHA Guidelines for CPR and ECC.