Intravenous calcium replacement for asymptomatic hypocalcemia of critical illness

Background: No studies have been performed to determine if intravenous calcium replacement in critically ill patients with mild, asymptomatic hypocalcemia improves clinical outcome. Methods: Case-control study of patients in the medical surgical intensive care unit of the San Francisco Veterans Affairs Medical Center. Two groups of patients were studied; one group consisting of all 15 patients who received intravenous calcium infusions in May 1999, and a control group consisting of an equal number of patients matched for severity of illness, as determined by Simplified Acute Physiology Score (SAPS II). Length of hospital stay and in-hospital mortality were calculated for each group. Results: The two groups did not differ significantly in baseline characteristics or severity of illness. The two groups also did not differ in mean serum calcium concentrations or degree of hypocalcemia during their hospital course. The calcium replacement group, however, had a longer hospital stay (20.7 vs. 12.4 days, p = 0.02). Conclusions: Intravenous calcium. replacement in mild, asymptomatic hypocalcemia of critical illness does not seem to benefit patients and may be associated with longer hospital stays.