Preemptive Antibiotic Treatment Based on Gram Staining Reduced the Incidence of ARDS in Mechanically Ventilated Patients

Background: Ventilator-associated pneumonia (VAP) is one of the major complications in the intensive care unit. VAP sometimes results in acute respiratory distress syndrome (ARDS), and the associated mortality is high. We hypothesized that preemptive antibiotic therapy based on results of bedside gram staining would reduce the incidence of VAP. Methods: Patients who were endotracheally intubated in our intensive care unit for more than 72 hours were included. Patients younger than 16 years of age or patients died because of brain death were excluded. The study was divided into two periods. During the first period, we used antibiotics according to the American Thoracic Society guidelines. During the second period, antibiotics were given according to the results of bedside gram staining even before radiographic infiltrate appeared. Results: One hundred twenty-eight patients and 133 patients were included in the first and second periods, respectively. The incidence of VAP was significantly decreased in the second period (first period, 22%; second period, 9%, p < 0.01). The incidence of ARDS was also decreased significantly in the second period (first period, 11%; second period, 3%, p < 0.01). The duration and total amount of antibiotics administered did not increase in the second period. VAP associated mortality was significantly lower in the second period (first period, 5%; second period, 0.8%, p < 0.05). Conclusion: Early diagnosis and treatment of respiratory infection based on results of gram staining significantly reduced the incidences of VAP and ARDS without an increase in the use of antibiotics.