Pre-emptive broad-spectrum treatment for ventilator-associated pneumonia in high-risk patients

Patients requiring mechanical ventilation (MV) for >48 h after major heart surgery (MHS) are at a high risk of acquiring ventilator-associated pneumonia (VAP) and tracheobronchitis (VAT). Most non-pharmacological interventions to prevent VAP in such patients are usually already implemented. The objective of this study was to evaluate the efficacy in preventing lower respiratory infections of antibiotics active against multidrug-resistant pathogens in this very high-risk population.

We performed a prospective randomized open-label study of MHS patients requiring MV for >48 h. Patients were randomly allocated to one of two groups: the intervention group, which received a 3-day course of linezolid and meropenem, and the control group, which received the standard of care. The main outcome was the development of VAP or VAT.

Overall, of the 78 patients included in the study, 40 were in the intervention group and 38 in the control group. Both groups were comparable. Data for the intervention and control groups respectively were as follows: VAP + VAT/1,000 days was 31.79 vs 64.78 (p = 0.03), median length of MV before the first episode of VAP or VAT 9 vs 4.5 days (p = 0.02). No significant differences were observed in median length of stay in the intensive care unit, median length of hospital stay, antibiotic use, Clostridium difficile infection, and overall mortality rate. We detected linezolid-resistant coagulase-negative and coagulase-positive staphylococci in the MHS intensive care unit after the study period.

A pre-emptive approach with broad-spectrum antibiotics may be effective in reducing the incidence and delaying the onset of VAP + VAT after MHS. The ecological consequences have to be carefully evaluated in future trials.