Abstract 10906: Association of Serum Magnesium Level on Emergency Department Arrival and Favorable Neurologic Outcome After Out-of-Hospital Cardiac Arrest

Abstract

Introduction: Electrolyte disturbances are associated with sudden cardiac arrest based on several cohort studies. However little is known about the association between serum magnesium(S-Mg) level at ED arrival and survival of out-of-hospital cardiac arrest (OHCA) patients. Hypothesis: We hypothesized S-Mg level at ED arrival is associated with favorable neurologic outcome of OHCA patients. Methods: This is an observational study using Korean Cardiac Arrest Research Consortium (KoCARC) data from October 2015 to June 2020. EMS treated OHCA patients over 18 years old who survived to ICU admission were included. Those without S-Mg level were excluded. Exposure is S-Mg level at emergency department (ED) arrival and outcome was favorable neurologic outcome (cerebral performance category 1 or 2) at hospital discharge. S-Mg was categorized into three groups; Low group; 0-1.7mg/dl, Normal group;1.7-2.3mg/dl, High group; over 2.3mg/dl). Multivariable logistic regression was performed to calculate adjusted odds ratios (AORs) with 95% confidence intervals (95% CIs) for outcome. Results: From total 10,897 OHCA patients, 2,789 patients survived to ICU admission and 1,370 patients had initial S-Mg result. Favorable neurologic outcome was 27.4% in low group, 55.7% in normal group and 23.0% in high group. After adjusting potential confounders in multivariable logistic analysis, compared to the normal group, AOR was 0.28 (95% CI 0.11-0.75) at low group and 0.43 (95% CI 0.23-0.82) at high group. Conclusion: Low (S-Mg less than 1.7 mg/dl) or high (S-Mg over 2.3mg/dl) S-Mg level measured initially at ED arrival for OHCA patients was associated with worse neurologic outcome compared to normal S-Mg level (S-Mg 1.7-2.3mg/dl). Based on this study, further study is needed to investigate the optimized S-Mg level for OHCA patient under resuscitation.