Objective  To investigate the efficacy of amiodarone and lidocaine in cardiac arrest patients.

Methods  We searched the PubMed, Embase, Cochrane Library, and Web of Science databases through to January 1, 2024. All studies comparing lidocaine, amiodarone, and placebo for cardiac arrest were included. Meta-analysis was performed, and the primary outcome was survival to hospital discharge. Secondary outcomes was survival to 24 h or hospital admission.

Results  Three RCTs and seven non-randomized intervention studies were included. Compared with placebo, amiodarone can improve the likelihood of survival to 24 h/hospital admission (OR=1.32, 95% CI: 1.12-1.54) in RCTs, while this significance was not found in non-randomized intervention studies (OR=0.79, 95% CI: 0.39-1.61). In both RCTs and non-randomized intervention studies, amiodarone did not significantly improve discharge survival rate compared with placebo (OR=1.19, 95% CI: 0.98-1.44 and OR=1.14, 95% CI: 0.44-2.99). Lidocaine was more effective than placebo in improving both survival to 24 h/hospital admission (OR=2.36, 95% CI: 1.47-3.80) and discharge from hospital (OR=2.10, 95% CI: 1.21-3.64) in non-randomized intervention studies. Amiodarone showed no significant difference in improving survival to 24 h/admission to hospital compared with lidocaine in RCTs, while amidoraone was inferior to lidocaine in improving 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)in non-randomized intervention study.

Conclusion  Limited RCTs directly compared amiodarone and lidocaine. No significant difference was found between amiodarone and lidocaine in improving 24 h/admission survival rate in RCTs. While compared to amiodarone and placebo, lidocaine can improve 24 h/admission survival rate and discharge survival rate in non-randomized intervention studies.