Amiodarone Compared with Lidocaine for Out-Of-Hospital Cardiac Arrest with Refractory Ventricular Fibrillation on Hospital Arrival: a Nationwide Database Study.

Purpose: The latest resuscitation guidelines recommend the use of amiodarone in adult patients with out-of-hospital cardiac arrest (OHCA) and refractory ventricular fibrillation (VF) to improve the rates of return of spontaneous circulation. However, there is limited evidence to suggest that amiodarone is superior to lidocaine with respect to survival at discharge. The purpose of the present study was to evaluate the hypothesis that amiodarone is superior to lidocaine with regard to the rate of survival to hospital discharge for OHCA patients with VF/pulseless VT (pVT) on hospital arrival.

Methods: Using the Japanese Diagnosis Procedure Combination inpatient database, we identified 3951 patients from 795 hospitals who experienced cardiogenic OHCA and had refractory ventricular fibrillation on hospital arrival between July 2007 and March 2013. The patients were categorized into amiodarone (n = 1743) and lidocaine (n = 2208) groups, from which 801 propensity score-matched pairs were generated.

Results: There was no significant difference in the rate of survival to hospital discharge between the amiodarone and lidocaine groups (15.2 % vs. 17.1 %; difference, -1.9 %; 95 % CI, -5.5 to 1.7) in propensity score-matched analyses. Cox regression analyses did not indicate significant in-hospital mortality differences between the amiodarone and lidocaine groups for the propensity score-matched groups (hazard ratio, 1.05; 95 % CI, 0.94 to 1.17).

Conclusions: The present nationwide study suggested that there was no significant difference in the rate of survival to hospital discharge between cardiogenic OHCA patients with persistent ventricular fibrillation on hospital arrival treated with amiodarone or lidocaine.