Mortality in Ventilator-Associated Tracheobronchitis and Pneumonia in Oncology Patients: The Impact of Microbiological Aspects.

Background: Most evidence on ventilator-associated pneumonia (VAP)-related and ventilator-associated tracheobronchitis (VAT)-related mortality comes from general ICU settings, with limited data on critically ill cancer patients. This study aimed to characterize the microbiological profile and resistance patterns in an oncology hospital and evaluate their impact on 14-day mortality. Methods: We conducted a retrospective analysis of VAP and VAT cases in an oncology ICU in Brazil (Jan-Dec 2024), assessing bacterial frequency, multidrug-resistant organisms (MDRO), and mortality. Multivariate analysis was used to identify the variables significantly associated with mortality. Results: Among 85 ICU patients, tracheobronchitis was more frequent (59%) than pneumonia (41%). Most were male (61%) with a median age of 62 years and had solid tumors (85%), mainly in the lungs and neck. Of 109 samples, P. aeruginosa (27%), K. pneumoniae (20%), and S. maltophilia (17%) were the most common pathogens. MDRO was particularly high in A. baumannii (82%). Overall, 14-day mortality was 55%. MDR was not associated with mortality (p = 0.3), but VAP (OR 4.20, p = 0.004) and infections with positive blood culture (OR 5.38, p = 0.023) were independently associated with mortality. Conclusion: This study provides valuable insights into the microbiological profile of patients with VAP and VAT in an oncological ICU and its impact on mortality. Mortality was not associated with MDR, possibly reflecting the high baseline risk from underlying conditions. However, patients with positive blood cultures had significantly higher mortality, suggesting a more invasive disease.