Treatment failure in patients with ventilator-associated pneumonia.

Ventilator-associated pneumonia (VAP) is one of the most important infectious diseases in the intensive care unit (ICU). In some series the attributable mortality of VAP may reach 30%, and the adequacy of the initial empirical treatment greatly influences the prognosis. Treatment failure can be anticipated in approximately 30 to 40% of patients developing pneumonia during mechanical ventilation and this situation is associated with an adverse outcome in terms of morbidity. For these reasons, the lack of response to empirical antibiotic treatment should be recognized early in the course of VAP, and a clear strategy for clarifying the causes of failure should be implemented. Resolution of VAP depends not only on the accuracy of microbial diagnosis but also on comorbidities, the response of the host to the infection, concomitant infections, and the correct clinical diagnosis. Treatment failure can be defined by the pattern of resolution of VAP, which is clearly established in the literature.