Effect of magnesium supplementation on lactate clearance in critically ill patients with severe sepsis: a randomized clinical trial

Objectives In this study, changes in lactate clearance following magnesium supplementation were evaluated in critically ill patients with severe sepsis. Methods Fifty-eight patients with severe sepsis were randomly assigned to receive either magnesium (n = 30) or placebo (n = 28). Patients in the magnesium group received intravenous magnesium sulfate to maintain serum magnesium level around 3 mg/dL for 3 days. The placebo group received the same volume of normal saline. Change in lactate clearance was considered primary outcome of the study. Results Mean increase in the lactate clearance in the magnesium group was significantly higher than the placebo group on day 2 (27.53% vs. 23.79% respectively, p < 0.001) and day 3 (49.83% vs. 37.02% respectively, p < 0.001). Time to lactate clearance was also significantly shorter in the magnesium group than the placebo group (47.28 +/- 20.59 vs. 61.20 +/- 24.31 h respectively, p = 0.03). Sepsis-related mortality was not significantly different but median length of ICU stay was significantly shorter in the magnesium group than the placebo group (8 vs. 15 days respectively, p < 0.01). Conclusions Magnesium supplementation increased lactate clearance in critically ill patients with severe sepsis. Optimizing serum magnesium level near the upper limit of the normal range may improve severe sepsis outcomes.