Dynamic changes of serum trace elements following cardiac surgery: A systematic review and meta-analysis

BACKGROUND: Cardiac surgeries are known to induce an inflammatory response. Besides, dietary factors such as trace elements contribute to promoting cardiovascular health by maintaining oxidative balance. Here we systematically review the literature about alterations in serum concentrations of zinc (Zn), copper (Cu), and selenium (Se) in response to cardiac surgeries. METHODS: A systematic search was performed on databases until the end of December 2022. Studies assessing the changes of mentioned elements in adult patients undergoing cardiac surgery were included. Changes in the means and standard deviations of the elements before and after the cardiac surgery were utilized as desired effect sizes. RESULTS: Among 1252 records found in the primary search, 23 and 21 articles were included in the systematic review and meta-analysis respectively. Seventeen studies evaluated the changes in serum Zn and Cu levels, and fifteen studies assessed Se levels. According to the results of quantitative analysis, Zn, Cu, and Se concentrations, one day after the surgery were significantly lower than preoperative values (WMD for Zn: 4.64 µmol/L [3.57-5.72], WMD for Cu: 1.62 µmol/L [0.52-2.72], and WMD for Se: 0.1 µmol/L [0.03-0.16]). The concentration of trace elements recovered gradually during the first-week post-operation and reached preoperative levels or even higher. CONCLUSION: Serum trace elements dropped significantly soon after the cardiac surgery, but they reached their baseline levels mostly during the first week after the surgery. Future studies are warranted to elucidate the impact of alterations in serum concentration of trace elements on the outcomes and complications of open-heart surgeries.