allopurinol and Shock--Traumatic

51 burned patients with TBSA over 30% were studied prospectively. MOF developed in 17 of them. Postburn MOF occurred mainly in those with TBSA over 70%. Mortality of MOF was directly proportional to the number of organs involved. The incidence of pulmonary failure was the highest, and the highest mortality was attributed to renal failure. MOF occurring in the early stage was more related to burn shock, and those occurring in the late stage was predisposed mainly by infection. Oxygen free radicals play an important role in the genesis and development of postburn MOF. In this study, it was revealed that antiperoxidation ability declined, active oxygen was increased, and lipid peroxidation became excessive after the burn injury. It was also found that oxygen free radical-mediated effects produced more serious damages in patients with MOF than those without, and also more in those died than the survivors. The hypoxanthine-xanthine oxidase system was a significant source of oxygen radicals after the burn injury. There were also significant changes in plasma TXA2 and PGI2 levels postburn. The marked increase in TXA2/PGI2 ratio indicated imbalance between TXA2 and PGI2, which was correlated well with burn size and closely related to the development of postburn MOF. The excessive production of TXA2 might trigger or accelerate the formation of microaggregates and thromboxane, subsequently leading to visceral damages and failure.

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Burns; Female; Humans; Male; Malondialdehyde; Multiple Organ Failure; Shock, Traumatic; Superoxide Dismutase; Thromboxane B2; Xanthine Oxidase

The role of oxygen-derived free radicals and lipid peroxidation in the pathogenesis of acute gastric mucosal erosion was investigated in rat models produced by burn shock stress, by treatment with regional hyperthermia, platelet activating factor, and compound 48/80, and by ischemia-reperfusion. In all experimental models, the increase in the gastric erosions and in TBA reactants in the gastric mucosa were significantly inhibited by the treatment with superoxide dismutase (SOD) and/or catalase. Pretreatment with allopurinol, a competitive inhibitor of xanthine oxidase, prevented considerably the gastric injury (a) induced by burn shock, (b) produced by treatment with compound 48/80, and (c) caused by ischemia-reperfusion. By the treatment with anti-rat neutrophil antibody, the gastric mucosal injuries induced by regional hyperthermia, platelet activating factor, and compound 48/80 were significantly inhibited; however, burn shock and ischemia-reperfusion injuries were not inhibited. These results suggest that oxygen-free radical and lipid peroxidation contribute to the formation of gastric mucosal lesions, and that the sources of oxygen radicals seem to be different among these experimental models.

Topics: Allopurinol; Animals; Burns; Female; Free Radical Scavengers; Free Radicals; Gastric Mucosa; Hyperthermia, Induced; Lipid Peroxidation; Male; Oxygen; p-Methoxy-N-methylphenethylamine; Platelet Activating Factor; Rats; Reperfusion Injury; Shock, Traumatic

The effect of free radicals scavengers (SOD and allopurinol) on the adherence of leukocytes and the blood flow of capillaries in spinotropizus muscle was observed in rats with burn shock. The changes in water content in heart, liver, lung, spleen, kidney and burned skin were measured. The survival time of the animals was recorded. The results showed that the number of the adherence of WBC decreased obviously, the amount of open capillaries increased, and the survival time of the animals with thermal injury prolonged by pretreating with SOD and allopurinol. The results of SOD were better than that of allopurinol. SOD also prevented the increase of water content in the lung and the burned skin, while allopurinol did not have this effect. It was shown that the therapeutic effect of SOD would appear if the medicine were given before or immediately after burn. However when SOD was administered half an hour after burn, there was no effect on adherence of WBC. These results confirm that superoxide free radical may be responsible for the adherence of WBC and hypoperfusion of microcirculation during burn shock. The scavengers have an important role in preventing microcirculatory disturbances, but it should be used as early as possible after thermal injury in order to block the response chain caused by free radicals.

Topics: Allopurinol; Animals; Burns; Female; Male; Microcirculation; Rats; Rats, Inbred Strains; Shock, Traumatic; Superoxide Dismutase