Figure 2. Hydrogen peroxide (H2O2) concentrations in venous blood from the femoral vein of the leg ([diamond], local) before and after application of a pneumatic tourniquet for bloodless knee surgery and simultaneously from an antecubital vein of an arm ([diamond], systemic). Significance at P < 0.05;* versus preoperatively (Pre-OP);(double dagger) versus 0.5 min;(paragraph) versus 5 min;(section) versus systemic.