OXIDATIVE STRESS-INDUCED BY BLOODLESS LIMB SURGERY ON HUMANS

Measure of oxidative stress were studied in blood samples from 10 pati ents undergoing bloodless lower limb surgery. Ischaemia induced a sign ificant increase in plasma hypoxanthine concentration and xanthine oxi dase activity both in the operated leg and in the systemic circulation . Five minutes after reperfusion. ratio of xanthine oxidase/total xant hine oxidase and dehydrogenase activities rose moderately, whereas at 20 min xanthine oxidase accounted for all xanthine oxido-reductase act ivity in the systemic circulation. A significant increase in blood glu tathione redox ratio, enhanced oxidation of haemoglobin to methaemoglo bin and rise in plasma haemoglobin concentration were present only in the operated limb. Thus, although the level of the potential free radi cal generators ruse significantly both locally and in the systemic cir culation, oxidative stress, as indicated by blood glutathione and eryt hrocyte injuries, remained limited to the reperfused leg.