Choosing antibiotics for patients who have nosocomial pneumonia

Pseudomonas aeruginosa is a major cause of nosocomial infections, including ventilator-associated pneumonia (VAP). Effective management of pneumonia caused by this pathogen has been hindered by the increased incidence of multidrug resistance and limited treatment options. The results of a study conducted in Spain underscore the importance of choosing the right antibiotic-or combination of antibiotics-for the initial empiric therapy.

Garnacho-Montero and coworkers conducted a retrospective, multicenter study that included 183 adults with VAP and respiratory cultures positive for P aeruginosa. The initial empiric antibiotic therapy was inappropriate in 40 patients. Compared with combination therapy, monotherapy was more likely to be inappropriate.

The mortality rate was significantly higher in patients who received inappropriate antibiotics than in those who received at least 1 antibiotic with in vitro activity against P aeruginosa (72.5% vs 23.1%; P < .05). The results of regression analysis indicated that the independent risk factors for mortality were inappropriate antibiotic therapy, age, and the presence of chronic cardiac insufficiency.