Polytrauma is a serious threat to human life not only due to its direct damage to vital organs, but also to the development of significant oxidative distress that gives rise to multiple organ dysfunction. At the same time, the risk of lifethreatening infectious complications increases. Objective: to study oxidative distress over time and its association with early pulmonary infectious complications in patients with polytrauma. Subjects and methods. The authors examined 35 patients with polytrauma in the first 6—12 and 12—24 hours and 3, 5—7, and 10 days after injury and 25 healthy volunteers. Having regard to the development of pulmonary infectious complications, they formed two comparison groups of patients: 1) 15 patients without pneumonia and 2) 20 patients with pneumonia. The investigation used the antioxidant index (AOI) considering the activity of erythrocyte enzymes (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) and the degree of lipid peroxidation in the plasma (dienic conjugates and malonic dialdehyde) to estimate the balance between oxidative lesions and the performance of the body's antioxidant systems. Results. In both groups, the AOI reflects the oxidative stress state, as substantiated by negative values for the AOI with its normal value equal to zero. However, with the virtually parallel nature of AOI changes after injury in the patients with pneumonia, the values of the index were significantly lower than in those without complications within the first 6—12 and 12—24 hours and 5—7 days (p<0.05). Conclusion. This investigation has indicated that the AOI is an early candidate biomarker for the risk of infectious complications and its values are of prognostic value just within the first hours after injury.

Objective: to analyze the incidence of infectious pulmonary complications depending on the duration of mechanical ventilation and to study a spectrum of pneumonia pathogens and their antibiotic resistance in intensive care unit (ICU) victims with severe concomitant injury. Subjects and methods. Forty-eight ICU victims with severe concomitant injury were examined. The incidence of purulent tracheobronchitis and pneumonia was analyzed depending on injury severity scores (ISS) and mechanical ventilation (MV) duration. Microorganisms were identified and their antibiotic susceptibility was determined. Results. The risk of infectious pulmonary complications was significantly higher and proportional to MV duration in victims with severe concomitant injury on traditional MV as compared those without MV (or on noninvasive ventilation). The pathogens of infectious pulmonary complications were chiefly gram-negative bacteria. Conclusion. There is evidence that there is an association between the ISS, the performance and duration of MV, the structure of pathogens, and their antibiotic resistance. Key words: infectious pulmonary complications, pneumonia, concomitant injury, mortality.