Pneumonias associadas à ventilação mecânica por bactérias Gram-negativas em um hospital terciário: aspectos clínicos, epidemiológicos e microbiológicos

Abstract

Ventilator-associated pneumonia (VAP) is an important cause of healthcareassociated infections, resulting in prolonged hospitalization with increased morbidity and mortality. Gram-negative bacteria that are highly resistant to antimicrobials have been associated with VAP. The aim of this study was to assess the occurrence of VAP caused by Gram-negative bacteria and its clinical, epidemiological and microbiological aspects in patients hospitalized between 2018 and 2022 in a tertiary hospital in Juiz de Fora, MG. This is a cross-sectional, retrospective and descriptive observational study. Clinical, epidemiological and microbiological data were collected from hospital records and provided by the clinical analysis laboratory. Our results indicate that 241 patients admitted to a tertiary hospital were diagnosed with VAP related to gram-negative bacteria. The majority were male (55.6%) and concentrated in the over-65 age group (54%). Among the most common comorbidities were diseases of the circulatory system (28.2%). The average length of stay was 42.27 ± 47.93 days and mechanical ventilation time was 26.57 ± 20.44 days. A total of 315 gram-negative bacterial species were isolated from tracheal secretions, the most common being A. baumanni and K. pneumoniae (22.2%), followed by P. aeruginosa (20.6%). With regard to the susceptibility profile, K. pneumoniae showed high levels of resistance to ampicillin/sulbactam (87.1%), ceftazidime (82.9%), piperacillin/tazobactam (82.6%), cefepime (81.2) and ciprofloxacin and imipenem (80%). A. baumanni showed high levels of resistance to amikacin and meropenem (100%), cefepime (97.1%), ciprofloxacin (97.0%), imipenem (95.7%), ampicillin/sulbactam (95.4%) and ceftazidime (91.3%). For P. aeruginosa, the highest resistance rates were concentrated in the 50% range, with imipenem (53.3%) and meropenem (49.2%) standing out. Our results point to the need for knowledge of the epidemiology and ecology of each hospital environment, contributing to the construction of infection prevention policies, the containment of antimicrobial resistance and the rational use of antimicrobials.