Calcium in Out-of-Hospital Cardiac Arrest: No Benefit

Calcium is a guideline-recommended treatment in select patients with cardiac arrest caused by hyperkalemia, hypocalcemia, or calcium-channel blocker overdose. Might its use in a broader cardiac-arrest population be beneficial, given its positive effects on myocardial contractility? Researchers in Denmark randomized 391 adults (mean age, 68) with out-of-hospital cardiac arrest to receive one or two doses of calcium chloride (5 mmol, intravenous or intraosseous) or normal saline.

The primary endpoint, return of spontaneous circulation, was not statistically different between groups (19% in the calcium group and 27% in the normal-saline group; P=0.09), but the trend toward worse outcomes resulted in early termination of the trial. Additionally,…