According to a meta-analysis published in the Journal of Critical Care, prophylactic antibiotics delivered to the respiratory tract by nebulization in patients who were mechanically ventilated reduced the rate of ventilator-associated pneumonia (VAP).
However, no significant effects on either intensive care unit (ICU) mortality or risk for respiratory infections by multidrug-resistant pathogens were found.
Frederico Castro Costa Póvoa, MD, Pulmonary and Critical Care Division of the University Hospital of Universidade Federal de Juiz de Fora in Juiz de Fora, Brazil, and colleagues identified relevant trials that evaluated the effect of antibiotics delivered via the respiratory tract on the rate of VAP.
The study end point was the rate of VAP in patients who were mechanically ventilated. A total of 6 comparative trials with 1158 patients were included in the analysis. More than 600 patients received a prophylactic antibiotic.
When compared with placebo or no treatment, prophylactic antibiotics reduced the occurrence of VAP by an odds ratio (OR) of 0.53 (95% CI, 0.34-0.84). This was observed when the antibiotics were delivered by nebulization (OR, 0.46; 95% CI, 0.22-0.97), but not when they were given by intratracheal instillation (OR, 0.57; 95% CI, 0.28-1.15). However, when the groups were compared for the end point of ICU mortality, the use of prophylactic antibiotics did not confer a benefit (OR, 0.89; 95% CI, 0.64-1.25), nor did it affect the occurrence of VAP caused by multidrug-resistant pathogens (OR, 0.67; 95% CI, 0.17-2.62).
Study limitations included the length of time between the first and last studies, as clinical practices had changed during the course of those years. For example, intratracheal instillation is no longer practiced and nebulization techniques have improved since the first study included in the analysis was conducted. There is also the possibility that antibiotic formulations may have changed during that period as well.
Nonetheless, the investigators concluded that the results were valid and suggest that prophylactic use of nebulized antibiotics in patients who were mechanically ventilated may help prevent VAP.
Costa Póvoa FC, Cardinal-Fernandez P, Silva Maia I, Moura Reboredo M, Valle Pinheiro B. Effect of antibiotics administered via the respiratory tract in the prevention of ventilator-associated pneumonia: a systematic review and meta-analysis. J Crit Care. 2018;43:240-245.