Abstract 20688: Potassium-Facilitated Defibrillation in Patients With Prolonged Refractory Ventricular Fibrillation Cardiac Arrest

Introduction: Potassium-based cardioplegia is used in the operating theater to induce asystole. This effect is rapidly reversed with wash-out of the potassium resulting in resumption of electrical activity. This retrospective study examined 5 patients with refractory ventricular fibrillation (VF) cardiac arrest who achieved normal sinus rhythm after chemical defibrillation with exogenous KCl or resolution of endogenous hyperkalemia. Methods: From December 2015 to May 2016, 19 patients were transported to the University of Minnesota in ongoing refractory VF as part of the Minnesota Resuscitation Consortium Advanced Perfusion and Reperfusion Cardiac Life Support Strategy. ECMO was initiated on arrival. Coronary angiography was performed and significant coronary artery disease was treated as necessary. Three patients had continued VF despite multiple shocks and treatment with amiodarone, lidocaine, metoprolol, and propofol. These patients were given KCl 0.5 mEq/kg bolus as salvage therapy after 90-120 minutes of VF. Defibrillation was administered as needed. Two additional patients were hyperkalemic (Ku003e5.5) on arrival. Results: Of the 3 patients that received exogenous potassium bolus, 2 achieved sustained ROSC. The third patient suffered recurrent VF after 30 seconds of sinus rhythm and went on to die. One of the 2 patients that achieved ROSC survived to hospital discharge while 1 patient suffered severe anoxic brain injury and died. The average peak potassium level in these 3 patients was 7.2 mmol/L with normalization within 25 minutes. The EKG showed asystole immediately after treatment with spontaneous return of normal sinus rhythm within 10 minutes. A single defibrillation was necessary for 1 of the patients while the others achieved sinus rhythm spontaneously. The 2 patients with endogenous hyperkalemia spontaneously achieved normal sinus rhythm within 5-10 minutes of the initiation of ECMO and administration of sodium bicarbonate. Both survived to hospital discharge with CPC score of 1. Conclusion: Potassium-facilitated defibrillation is feasible in the setting of ECMO for patients with prolonged refractory VF arrest. Endogenous hyperkalemia may present an opportunity for enhanced defibrillation if adequate perfusion is provided.