Tachycardia; Unstable Wide Complex (with pulse)

Determine Patient Stability

Patient is considered unstable if there is hypotension, poor skin signs, shortness of breath, chest pain, evidence of CHF, or decreased mentation [or any other symptom felt to be caused by the bradycardia].

1. Evaluate ABC's
   • Stabilize Airway/Breathing
   • Apply oxygen
   • Place cardioversion/defibrillation pads
   • Establish IV
   • Monitors (Rhythm, Oximetry, BP)
   • Obtain 12 lead EKG
   • Code cart
2. Obtain history and perform physical examination and consider causes:
   • Differential diagnosis includes:
   • Ventricular tachycardia (Monomorphic)
   • Ventricular tachycardia (Polymorphic)
   • Atrial fibrillation w/ aberrancy
   • Atrial flutter w/ aberrancy
   • Supraventricular tachycardia (SVT ) w/ aberrancy
   • Pre-excited tachycardias with accessory pathway
   • Consider Causes
   • Acute myocardial infarction, pulmonary embolus
   • Hypovolemia/Hypoxia/Hypothermia
   • Metabolic: Thyroid disease, hyper/hypokalemia, hypercalcemia, acidosis, hypoglycemia
   • Drugs: Cocaine, Amphetamines, Decongestants, Ephedra, Ginseng
   • Pneumothorax or Tamponade
   • Cardiomyopathy/Valvular heart disease
   • Alcohol related ("Holiday heart")
   • Sepsis/Pneumonia
3. Treatment for unstable wide complex tachycardia:
   • Sedation if possible and immediate cardioversion (most rhythms)/defibrillation (Polymorphic VT).
   • Sedation:
   • If patient is conscious, provide sedation (agents such as Etomidate, Fentanyl or Midazolam are common choices)
   • Synchronized cardioversion:
   • Pads on patient (or paddles)
   • Press sync button (make sure to have 3 lead monitor leads attached to the defibrillator/cardiovertor)
   • Evaluate rhythm to determine appropriate initial Joule setting:
   • Afib: 100-200J
   • A-flutter/SVT: 50-100J
   • VT monomorphic: 100J
   • Defibrillation
   • Pad on patient (or paddles)
   • Polymorphic VT 360 J (monophasic) or 120-200J (biphasic)
   • Response to therapy
   • If no conversion, increase joules for subsequent shocks in stepwise fashion 100 ->200 ->300 ->360J. For cardioversion, make sure to press the sync button prior to each shock.
4. Standard laboratory evaluation (if indicated):
• CBC, Electrolytes, TSH, Cardiac enzymes and toxicology testing
• CXR
• EKG pre and post conversion (if conversion occurs)
5. Consultation and admission to hospital if indicated.

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