RESUMO
BACKGROUND & AIMS: Cardiac surgery is accompanied by oxidative stress and systemic inflammatory response, which may be associated with organ dysfunction and increased mortality. Selenium and selenoenzymes are important constituents of anti-oxidative defense. We hypothesized that high-dose sodium selenite supplementation can attenuate the postoperative inflammation and might, therefore, improve clinical outcome. METHODS: Randomized, placebo-controlled, double-blinded, bi-center study on 411 adult patients undergoing elective cardiac surgery. Patients received an intravenous bolus of 4000 µg selenium (in the form of sodium selenite) or placebo after induction of anesthesia and 1000 µg/d selenium or placebo during their intensive care unit (ICU) stay. Primary outcome measure was the Sequential Organ Failure Assessment (SOFA) score on the second postoperative day. Secondary endpoints included the change in perioperative selenium levels, change of inflammatory and cardiac markers, use of vasoactive medication, incidence of acute kidney injury, ICU and hospital length of stay, and mortality. RESULTS: The perioperative administration of high-dose sodium selenite prevented the postoperative drop of blood and serum selenium levels, reduced the number of patients depending on postoperative vasoactive support but failed to reduce the postoperative SOFA score and its related organ-specific scores compared to placebo. Except for an increase of postoperative procalcitonin and bilirubin levels in the sodium selenite group, other inflammatory markers, organ function variables and clinical endpoints remained unchanged. CONCLUSIONS: The perioperative administration of high-dose sodium selenite in cardiac surgery patients prevented the postoperative fall of blood selenium levels and reduced the need for postoperative vasoactive support by a yet unknown mechanism. TRIAL REGISTRATION: Registered under ClinicalTrials.gov Identifier no. NCT01141556.