Calcium use during cardiac arrest: A systematic review

INTRODUCTION: Calcium use during cardiac arrest has conflicting results in terms of efficacy. Therefore, we performed a systematic review evaluating the role of calcium administration in cardiac arrest. METHODS: We searched PubMed, Cochrane, and EMBASE for studies comparing calcium administration versus no calcium administration during cardiac arrest. The study was prospectively registered in PROSPERO (CRD42022316641) adhering to PRISMA guideline recommendations. The primary outcome was return of spontaneous circulation (ROSC) or survival at one hour. The secondary outcomes included survival to discharge or at 30 days, and favorable neurologic outcomes at 30 and 90 days. We planned to perform a random-effects meta-analysis of low risk of bias studies. We evaluated risk of bias with RoB-2 and ROBINS-I. RESULTS: We identified 1,921 articles and included ten studies with 2509 patients. We were not able to perform a meta-analysis with low-risk of bias studies as only one study was found to be at low-risk of bias. However, for the primary outcome, the three RCTs included showed no benefit with calcium administration during cardiac arrest for ROSC. For the secondary outcomes, based on the most recent study and lower risk of bias, there was a neutral effect for survival to discharge or at 30 days and neurologic outcomes at 30 days. However, there was unfavorable neurologic outcomes at 90 days. CONCLUSION: Based on our results, calcium administration in cardiac arrests shows no benefit and can cause harm. Further studies on this matter are likely not advisable.