Comparative Effectiveness of Amiodarone and Lidocaine for the Treatment of In-Hospital Cardiac Arrest.

BACKGROUND: American Heart Association Advanced Cardiac Life Support (ACLS) guidelines support the use of either amiodarone or lidocaine for cardiac arrest caused by ventricular tachycardia or ventricular fibrillation (VT/VF) based on studies of out-of-hospital cardiac arrest. Studies comparing amiodarone and lidocaine in adult populations with in-hospital VT/VF arrest are lacking.

RESEARCH QUESTION: Does treatment with amiodarone vs lidocaine therapy have differential associations with outcomes among adult patients with in-hospital cardiac arrest from VT/VF?

STUDY DESIGN AND METHODS: This retrospective cohort study of adult patients receiving amiodarone or lidocaine for VT/VF in-hospital cardiac arrest refractory to CPR and defibrillation between January 1, 2000, and December 31, 2014, was conducted within American Heart Association Get With the Guidelines-Resuscitation (GWTG-R) participating hospitals. The primary outcome was return of spontaneous circulation (ROSC). Secondary outcomes were 24 h survival, survival to hospital discharge, and favorable neurologic outcome.

RESULTS: Among 14,630 patients with in-hospital VT/VF arrest, 68.7% (n = 10,058) were treated with amiodarone and 31.3% (n = 4,572) with lidocaine. When all covariates were statistically controlled, compared with amiodarone, lidocaine was associated with statistically significantly higher odds of the following: (1) ROSC (adjusted OR [AOR], 1.15, P = .01; average marginal effect [AME], 2.3; 95% CI, 0.5 to 4.2); (2) 24 h survival (AOR, 1.16; P = 004; AME, 3.0; 95% CI, 0.9 to 5.1); (3) survival to discharge (AOR, 1.19; P < .001; AME, 3.3; 95% CI, 1.5 to 5.2); and (4) favorable neurologic outcome at hospital discharge (AOR, 1.18; P < .001; AME, 3.1; 95% CI, 1.3 to 4.9). Results using propensity score methods were similar to those from multivariable logistic regression analyses.

INTERPRETATION: Compared with amiodarone, lidocaine therapy among adult patients with in-hospital cardiac arrest from VT/VF was associated with statistically significantly higher rates of ROSC, 24 h survival, survival to hospital discharge, and favorable neurologic outcome.