What is the management for refractory ventricular fibrillation (v fib)?

Management of Refractory Ventricular Fibrillation

For refractory ventricular fibrillation (VF that persists after 3 defibrillation attempts), continue high-quality CPR with serial defibrillation while administering intravenous amiodarone 150 mg over 10 minutes followed by infusion, and consider adjunctive therapies including magnesium sulfate, beta-blockade, and dual-sequential defibrillation if standard measures fail. 1, 2, 3

Initial Defibrillation Protocol

• Deliver immediate non-synchronized shocks at 200J (monophasic) or per manufacturer recommendations (biphasic), followed by high-quality CPR at ≥100 compressions/minute with minimal interruptions 1
• If the first shock fails, escalate to 200-300J for the second shock, then 360J for the third attempt 1
• Maintain intervals between shocks of no more than 15 seconds to minimize interruptions in chest compressions 4

Pharmacological Management After Failed Initial Defibrillation

First-Line: Amiodarone

• Administer intravenous amiodarone 150 mg over 10 minutes, followed by continuous infusion at 1.0 mg/min for 6 hours, then maintenance at 0.5 mg/min 2, 3
• Amiodarone is FDA-approved specifically for frequently recurring VF refractory to other therapy and demonstrates rapid onset of antiarrhythmic activity 3
• Continue therapy for 48-96 hours until ventricular arrhythmias stabilize, though longer administration is safe if necessary 3

Epinephrine

• Give 1 mg epinephrine IV every 3 minutes throughout resuscitation efforts 4
• After 3 cycles without response, consider high-dose epinephrine (5 mg) 4

Alternative Antiarrhythmic Agents

• Lidocaine: 1.0-1.5 mg/kg bolus, with supplemental boluses of 0.5-0.75 mg/kg every 5-10 minutes (maximum 3 mg/kg total), followed by 2-4 mg/min infusion 2

  • Particularly useful when VF is thought related to myocardial ischemia 2
  • Reduce infusion rates in elderly patients and those with heart failure or hepatic dysfunction 2

• Magnesium sulfate: 8 mmol bolus injection followed by 2.5 mmol/h infusion 4, 2

  • Especially effective for VF associated with acute myocardial infarction or suspected hypomagnesemia 4, 5

Advanced Strategies for Persistent Refractory VF

Dual-Sequential Defibrillation (DSD)

• Consider DSD when standard defibrillation attempts fail 6, 7
• This involves using two defibrillators simultaneously with pads placed in different positions to alter the vector of current delivery 6
• While not yet incorporated into formal ACLS guidelines, emerging evidence supports its use in refractory cases 6, 8

Beta-Blockade

• Low-dose esmolol may be considered for refractory VF unresponsive to standard therapy 7
• Case reports demonstrate successful ROSC after esmolol administration when serial defibrillation and epinephrine failed 7
• Beta-blockers are the single most effective therapy for polymorphic VT storm 2

Extracorporeal CPR (E-CPR)

• E-CPR should be considered for refractory VF persisting >10 minutes in appropriate candidates at centers with capability 9
• Patients receiving E-CPR demonstrate significantly higher rates of sustained ROSC (95% vs 47.5%) and good neurological outcomes at discharge (40% vs 7.5%) compared to conventional CPR alone 9
• This represents the most promising intervention for truly refractory cases 8, 9

Critical Adjunctive Measures

Airway and Vascular Access

• Attempt endotracheal intubation and establish IV access without causing undue delay in CPR or defibrillation 4
• These procedures should be performed simultaneously by two operators when possible 4

Reversible Causes

• Systematically address the H's and T's: hypovolemia, hypoxia, acidosis, hypo/hyperkalemia, hypothermia, pneumothorax, tamponade, toxins, thrombosis (pulmonary and coronary) 1
• Correct electrolyte abnormalities, particularly potassium and magnesium 1

Paddle Position

• Consider changing defibrillator paddle position after multiple failed attempts 4

Duration of Resuscitation Efforts

• Do not abandon resuscitation while the rhythm remains recognizable VF 4
• Resuscitation attempts may reasonably last 10 minutes to over an hour depending on clinical circumstances 4
• Exceptions warranting prolonged efforts include hypothermia, near-drowning, and drug intoxication 4

Common Pitfalls to Avoid

• Never use class IC antiarrhythmics (flecainide, propafenone) during VF, as they may paradoxically increase defibrillation threshold 4
• Avoid excessive interruptions in chest compressions - the internal loop between shocks should not exceed 15 seconds 4
• Remove all glyceryl trinitrate patches from the chest wall before defibrillation to prevent explosions 4
• Do not delay defibrillation for intubation or vascular access - these are secondary priorities 4