SCHEDULED CHANGE OF ANTIBIOTIC CLASSES - A STRATEGY TO DECREASE THE INCIDENCE OF VENTILATOR-ASSOCIATED PNEUMONIA

The purpose of this study was to determine the impact of a scheduled c hange of antibiotic classes, used for the empiric treatment of suspect ed gram-negative bacterial infections, on the incidence of ventilator- associated pneumonia and nosocomial bacteremia. Six hundred eighty pat ients undergoing cardiac surgery were evaluated. During a 6-mo period (i.e., the before-period), our traditional practice of prescribing a t hird generation cephalosporin (ceftazidime) for the empiric treatment of suspected gram-negative bacterial infections was continued. This wa s followed by a 6-mo period (i.e., the after-period) during which a qu inolone (ciprofloxacin) was used in place of the third-generation ceph alosporin. The incidence of ventilator-associated pneumonia was signif icantly decreased in the after-period (n = 327) compared with the befo re-period (n = 353) (6.7 versus 11.6%; p = 0.028). This was primarily due to a significant reduction in the incidence of ventilator-associat ed pneumonia attributed to antibiotic-resistant gram-negative bacteria (0.9 versus 4.0%; p = 0.013). Similarly we observed a lower incidence of bacteremia attributed to antibiotic-resistant gram-negative bacter ia in the after-period compared with the before-period (0.3 versus 1.7 %; p = 0.125). These data suggest that a scheduled change of antibioti c classes can reduce the incidence of ventilator-associated pneumonia attributed to antibiotic-resistant gram-negative bacteria.