ABSTRACT
AIM: Study species composition and biological properties of microorganisms isolated from lower respiratory tract of 34 patients of surgical departments during mechanical lung ventilation. MATERIALS AND METHODS: 59 strains of microorganisms were isolated and identified by established methods from tracheobronchial secretion during intubation and extubation. Hemolytic and anti-lysozyme activity was determined in isolates by methods described previously (O.V. Bukharin, 1999). RESULTS: During extubation an increase of seeding of tracheobronchial secretion in patients, increase of microorganism species diversity and frequency of occurrence of highly virulent strains characterized by the ability to hemolyze erythrocytes and high values of anti-lysozyme activity were established. CONCLUSION: The data obtained may be used to prognose the risk of development of diseases of respiratory system.