Antiarrhythmia drugs for cardiac arrest: a systemic review and meta-analysis

Antiarrhythmia agents have been used in the treatment of cardiac arrest, and we aimed to review the relevant clinical controlled trials to assess the effects of antiarrhythmics during cardiopulmonary resuscitation.

We searched databases including Cochrane Central Register of Controlled Trials; MEDLINE, and EMBASE. Clinical controlled trials that addressed the effects of antiarrhythmics (including amiodarone, lidocaine, magnesium, and other new potassium-channel blockers) on the outcomes of cardiac arrest were included. Data were collected independently by two authors. The risk ratio of each outcome was collected, and meta-analysis was used for data synthesis if appropriate. Heterogeneity was assessed with the χ² test and the I ² test.

Ten randomized controlled trials and seven observational trials were identified. Amiodarone (relative risk (RR), 0.82; 95% confidence interval (CI), 0.54 to 1.24), lidocaine (RR, 2.26; 95% CI, 0.93to 5.52), magnesium (RR, 0.82; 95% CI, 0.54 to 1.24) and nifekalant were not shown to improve the survival to hospital discharge compared with placebo, but amiodarone, lidocaine, and nifekalant were shown to be beneficial to initial resuscitation, assessed by the rate of return of spontaneous circulation and survival to hospital admission, with amiodarone being superior to lidocaine (RR, 1.28; 95% CI, 0.57 to 2.86) and nifekalant (RR, 0.50; 95% CI, 0.19 to 1.31). Bretylium and sotalol were not shown to be beneficial.

Our review suggests that when administered during resuscitation, antiarrhythmia agents might not improve the survival to hospital discharge, but they might be beneficial to initial resuscitation. This is consistent with the AHA 2010 guidelines for resuscitation and cardiovascular emergency, but more studies with good methodologic quality and large numbers of patients are still needed to make further assessment.