The effect of mannitol on oxidation‐reduction potential in patients undergoing deceased donor renal transplantation—A randomized controlled trial

BACKGROUND: Mannitol, an osmotic diuretic, is proposed to be an oxygen radical scavenger. Mannitol is often used in renal transplantation to attenuate oxidative stress and thus to protect renal graft function. We tested the hypothesis that mannitol reduces overall oxidative stress during deceased donor renal transplantation. METHODS: We randomly assigned 34 patients undergoing deceased donor renal transplantation to receive a solution of mannitol or placebo shortly before graft reperfusion until the end of surgery. We evaluated oxidative stress by measuring the static oxidative‐reduction potential (sORP) and the capacity of the oxidative‐reduction potential (cORP). sORP and cORP were measured pre‐operatively, before and within 10 minutes after graft reperfusion, and post‐operatively. RESULTS: Seventeen patients were enrolled in the mannitol group and 17 patients were enrolled in the placebo group. Mannitol had no significant effect on sORP (148.5 mV [136.2; 160.2]) as compared to placebo (143.6 mV [135.8; 163.2], P = .99). There was also no significant difference in cORP between the mannitol (0.22 µC [0.16; 0.36]) and the placebo group (0.22 µC [0.17; 0.38], P = .76). CONCLUSION: Mannitol showed no systemic redox scavenging effects during deceased donor renal transplantation. To evaluate the direct effect of mannitol on the renal graft further studies are needed. Trial registration: ClinicalTrials.gov NCT02705573.