What is the treatment for ventricular fibrillation?

Treatment of Ventricular Fibrillation

Immediate defibrillation is the definitive treatment for ventricular fibrillation (VF), with CPR performed while preparing for defibrillation to maintain perfusion. 1

Initial Management Algorithm

1. Recognition and Basic Life Support

   • Confirm pulselessness and begin high-quality CPR immediately
   • Compression depth: 2/3 of chest anterior-posterior diameter (at least 2 inches in adults)
   • Rate: at least 100/min
   • Allow complete chest recoil between compressions
   • Minimize interruptions in chest compressions

2. Defibrillation

   • Apply monitor/defibrillator as soon as available
   • When VF is confirmed, deliver shock immediately
   • Energy recommendations:
     • Adults: 120-200J biphasic or 360J monophasic
     • Children: First shock 2 J/kg; second 4 J/kg; subsequent shocks ≤10 J/kg 1
   • Resume chest compressions immediately after shock delivery
   • Minimize time between chest compressions and shock delivery 1

3. CPR Continuation

   • Continue CPR for 2 minutes between rhythm checks
   • For unwitnessed arrests with response times >5 minutes, consider 1.5-3 minutes of CPR before first defibrillation 2
   • CPR prolongs VF, delays asystole onset, and extends the window for effective defibrillation 1

Advanced Life Support Interventions

1. Airway Management

   • Establish advanced airway when possible without interrupting chest compressions
   • After advanced airway placement: 1 breath every 6 seconds (10 breaths/min) with continuous compressions

2. Medication Therapy

   • Epinephrine: 1 mg IV/IO every 3-5 minutes
   • Amiodarone: For refractory VF (persists after initial shocks)
     • 300 mg IV/IO bolus for first dose
     • Consider additional 150 mg for recurrent/persistent VF
     • Maintenance infusion: 1 mg/min for 6 hours, then 0.5 mg/min 3
   • Alternative antiarrhythmics if amiodarone unavailable:
     • Lidocaine: 1-1.5 mg/kg IV initial dose, followed by 0.5-0.75 mg/kg (maximum 3 doses) 1
     • Procainamide: 20-30 mg/min up to 12-17 mg/kg 4

Management of Refractory VF

Refractory VF is defined as VF persisting despite 3 standard defibrillation attempts, amiodarone administration, and standard ACLS 5, 6.

For refractory VF, consider:

1. Changing defibrillation strategy:

   • Adjust pad placement (vector change)
   • Consider increasing energy if available
   • Dual sequential defibrillation may be considered in extreme cases 5

2. Additional pharmacologic options:

   • Beta-blockers (esmolol) may be considered, particularly if ischemia is suspected 4, 5
   • Magnesium sulfate: 1-2g IV for suspected hypomagnesemia or torsades de pointes 4
   • Correct electrolyte abnormalities (particularly potassium and magnesium)

3. Extracorporeal CPR (ECPR):

   • Consider for selected patients with refractory VF, especially younger patients with witnessed arrest and minimal comorbidities
   • Associated with improved neurological outcomes in refractory VF cases 7

Special Considerations

1. Underlying causes: Identify and treat potential reversible causes (5H's and 5T's):

   • Hypovolemia, Hypoxia, Hydrogen ion (acidosis), Hypo/hyperkalemia, Hypothermia
   • Tension pneumothorax, Tamponade, Toxins, Thrombosis (coronary or pulmonary)

2. Post-resuscitation care:

   • Targeted temperature management
   • Hemodynamic optimization
   • Urgent coronary angiography if suspected cardiac etiology

3. Witnessed VF in cardiac catheterization lab:

   • Immediate defibrillation
   • Consider immediate revascularization if during acute coronary syndrome 1

Common Pitfalls to Avoid

1. Prolonged interruptions in chest compressions - Minimize pauses for rhythm checks and defibrillation
2. Delayed defibrillation - Defibrillate as soon as VF is identified on the monitor
3. Ineffective chest compressions - Ensure proper depth, rate, and complete recoil
4. Hyperventilation - Avoid excessive ventilation which can decrease venous return
5. Failure to consider reversible causes - Systematically evaluate and treat potential underlying causes

Early defibrillation remains the cornerstone of VF treatment, with high-quality CPR providing critical perfusion before, between, and after shocks. The combination of these interventions, along with appropriate medications and addressing underlying causes, offers the best chance for successful resuscitation.