We are planning to perform a double-blind randomized controlled trial. In the study, mannitol 20% with a dose of 1g / kg / BW (5 ml / kg / BW) will be compared to placebo with NaCl 0.9% in the dose of 5 ml / kg / BW. Patients will be randomized to receive either the mannitol or NaCl. The follow-up of the study is 24 hours. The following biomarkers will be determined befor induction of anesthesia and 24 hours after administration of study medication: CCL2, CHI3LI, GH, HGF, MMP1, MMP8, Tie2, TNF-R1, VCAM-1, KIM-1, Cystatin C, FGF23, IGFB7, NGAL and IL 18. Data will be collected, compared and published at the end of the study. It is planned to include a total of 34 patients in the study.