Epidemiology of ventilator-associated tracheobronchitis and vantilator-associated pneumonia in patients with inhalation injury at the Burn Centre in Brno (Czech Republic).

Aim. The aim of this work is to determine the incidence of ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP) and to define the define the most important respiratory pathogens in patients with inhalation injury. Introduction. Infectious complications in severely burned patients present serious problems. Patients with inhalation injuries are exposed to greater risk owing to the possible development of infectious complications in the lower respiratory tract. VAP is the predominant cause of death in these patients. This is due to the increasing resistance of strains of Gram-negative bacteria such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae. Design. Retrospective, monocentric. Setting. A five-bed burn intensive care unit. Material and methods. Between 2004 and 2009, 348 adult patients were hospitalized in the intensive care unit of the Department of Burns and Reconstructive Surgery, Brno University Hospital, Czech Republic. Of these, 127 (36.49%) were diagnosed by bronchoscopy as having inhalation injury. The prerequisite for inclusion in the cohort was an inhalation injury requiring artificial ventilation for at least 48 h. The lower airway microbiological condition was monitored regularly by sampling biological material for cultures (sputum, tracheobronchial aspirates, etc.). For the diagnosis of VAP and VAT we used the Centers for Disease Control and Prevention criteria and the Clinical Pulmonary Infection Score. Results. The average age of the 127 patients (31 women/96 men) included in the study was 38.4 yr (range, 21-69 yr) and the average total body surface area (TBSA) burned was 29.3% (range, 2-75%). The average length of hospital stay was 49.4 days (range, 4-150 days) and the duration of mechanical ventilation 8.7 days; 18 patients (14.2%) died. In patients with inhalation injury, 309 strains of bacteria were cultivated from the lower respiratory tract, of which 234 were Gram-negative. All of these bacterial strains were isolated in significant quantities for lower respiratory tract infection. The most common bacteria isolated from the lower respiratory tract was Klebsiella pneumoniae (78 times), followed by Pseudomonas aeruginosa (49x), and Acinetobacter baumannii (28x). VAT was diagnosed in 109 patients (85.8%) in the cohort. The incidence of VAT was calculated to be 98.8 per 1000 days of mechanical ventilation. VAP was diagnosed in 34 patients in the cohort (26.8%). The incidence of VAP was calculated as being 30.8 cases per 1,000 days of mechanical ventilation. In eight patients (23.5%), VAP was diagnosed within 5 days of initiation of mechanical ventilation (early onset) and in 26 patients (76.5%) after a longer period (late onset). The most common aetiological agent of VAT and VAP was Klebsiella pneumoniae (respectively 41.3% and 35.3%). Conclusion. In this study we were able to determine the incidence of VAP and VAT in patients with inhalation injury. In spite of the advances in diagnostics and therapy, inhalation injury is still burdened with disappointingly high morbidity and mortality rates. For this reason, the treatment of VAP remains a major challenge for all physicians caring for patients with inhalation injury.