[Review of the effectiveness of an empirical antibiotic therapy in suspected ventilator-associated pneumonia].

Background: Ventilator-associated pneumonia (VAP) occurs in approximately 10-20% of mechanically ventilated patients, and is associated with an extremely high mortality rate (up to 70%). The purpose of the study was to determine the susceptibility spectrum of Klebsiella, Pseudomonas and Acinetobacter strains isolated from VAP patients.

Methods: We analysed 81 strains of microorganisms isolated from bronchoalveolar lavages (BAL) of VAP patients. The minimal inhibitory concentrations (MIC) of antibiotics recommended for empirical therapy were determined using an automated VITEK 2 system, and for the MIC of doripenem - the Etest assay. Results were analysed following the guidelines of the Clinical and Laboratory Standards Institute.

Results: For infections caused by the group of bacteria under investigation, the most successful regimen was monotherapy with carbapenems (doripenem, meropenem and imipenem). Cephalosporins (cefepim and ceftazidim) were less effective in vitro. The worst results were obtained with the combination of piperacillin/tazobactam with aminoglycosides (amikacin or gentamicin) or fluoroquinolones (ciprofloxacin).

Conclusions: Antibiotic monotherapy proved to be more effective in VAP patients than combined therapy; the best results were achieved with carbapenems. Doripenem showed strong activity in vitro against P. aeruginosa and Klebsiella sp. and should be considered for empirical VAP therapy; however, carbapenems may be less effective against Acinetobacter baumannii. The wide range of bacteria, and their broad range of susceptibility to antibiotics, suggests the need for modification of current recommendations.