Serum Concentrations of Trace Elements Zinc, Copper, Selenium, and Manganese in Critically Ill Patients

We measured serum concentrations of trace elements and evaluated their clinical significance in relation to treatment outcomes of critically ill patients. A total of 167 participants (105 men and 62 women; average age, 61.4 years; age range, 18–90 years) were enrolled. Arterial blood concentrations of the trace elements zinc, copper, selenium, and manganese were measured every 14 days. At the time of intensive care unit (ICU) admission, serum concentrations of zinc, selenium, copper, and manganese were lower than the normal values in 75.1, 1.8, 37.8, and 2.1% of patients, respectively. Serum trace element concentrations measured on day 14 of ICU stay were higher than those measured at the time of ICU admission for zinc (53.3 → 80.7 μg/L) and copper (87.1 → 102.3 μg/L). Increased serum zinc and copper concentrations during ICU care were associated with a significantly lower mortality compared to decreased concentrations of zinc (15.6 vs. 83.3%, p = 0.003) and copper (5.6 vs. 50.0%, p = 0.013). At the time of ICU admission, low serum levels of zinc and copper were observed. Patients with increased serum concentrations of zinc and copper had significantly lower mortality.