Comparative Efficacy of Amiodarone and Lidocaine in Patients with Cardiac Arrest: A Systematic Review and Meta-analysis

Objective To compare the efficacy of amiodarone and lidocaine in cardiac arrest patients with pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF). Methods The PubMed, Embase, Cochrane Library, and Web of Science databases were searched from its establishment to January 1, 2024. All studies comparing lidocaine, amiodarone, and placebo for cardiac arrest were included. The primary outcome was survival to hospital discharge. Secondary outcomes were 24 h / survival to hospital admission. Results Three RCTs and seven observational studies were included. Compared with placebo, amiodarone improved 24 h /admission survival rate (OR 1.32, 95% CI 1.12-1.54) in RCTs, but this significance was not found in observational studies (OR 0.79, 95% CI 0.39-1.61). In both RCTs and observational studies, amiodarone did not significantly improve discharge survival rate (OR 1.19, 95% CI 0.98- 1.44 and OR 1.14, 95% CI 0.44-2.99). Compared with placebo, lidocaine improved both 24 h /admission survival (OR 2.36, 95% CI 1.47-3.80) and discharge survival (OR 2.10, 95% CI 1.21- 3.64) in observational studies. Lidocaine did not improve 24 h /admission survival rate in RCTs (OR 1.37, 95% CI 0.61-3.06) compared with amiodarone, while in observational studies lidocaine was more effective in both 24 h/admission survival rate (OR 0.72, 95% CI 0.53-0.98) and discharge survival rate (OR 0.81, 95% CI 0.76-0.87). Conclusions The research was limited by the number of included RCTs. In RCTs no significant difference was found between amiodarone and lidocaine in improving 24 h /admission survival rate； in observational studies, lidocaine improved 24 h /admission survival rate and discharge survival rate compared to amiodarone and placebo.