Abstract 152: Effect Of Calcium On Patient Outcomes In Pulseless Electrical Activity With Wide QRS-Complexes

Introduction: The Calcium for Out-of-hospital Cardiac Arrest (COCA)-trial recently found no benefit of administering calcium during out-of-hospital cardiac arrest in an unselected adult population. Still, calcium is recommended for cardiac arrest caused by hyperkalemia. Higher potassium levels have been found in cardiac arrest patients with wide QRS-complexes which may act as an indicator of hyperkalemia. Objectives: 1) To describe characteristics of patients with baseline PEA in out-of-hospital cardiac arrest, and 2) to determine the effect of calcium on return of spontaneous circulation (ROSC) in patients displaying PEA with wide and normal QRS-complexes. Methods: COCA was a randomized, double-blind, placebo-controlled trial of calcium administered immediately after the first and second epinephrine dose of adults in out-of-hospital cardiac arrest. Of the 391 included patients, this abstract included those with PEA at the last rhythm analysis prior to first trial drug administration. PEA was defined as any rhythm that was not ventricular fibrillation, ventricular tachycardia, or asystole. Wide QRS-complexes were defined as > 110 ms. Results: 104 patients had baseline PEA and available electrocardiograms. Demographics and electrocardiographic characteristics are presented in Table 1. The median heart rate was 42, half presented with an escape rhythm, and 70% had wide QRS-complexes. Half exhibited ST-elevation. The overall ROSC-rate was 31%. The relative risk of ROSC for patients receiving calcium as compared to placebo was 0.75 (95% confidence interval (CI) 0.33-1.72) in the normal QRS-group and 0.82 (95% CI 0.47-1.41) in the wide QRS-group. Conclusion: In adults with out-of-hospital cardiac arrest, baseline PEA rhythms often included bradycardia, escape rhythms, wide QRS-complexes, and/or ST-elevation. The effects of calcium administration on ROSC were similar in a subgroup analysis of normal vs. wide QRS-complexes.