|| Checking for direct PDF access through Ovid
Many systemic antibiotics penetrate poorly into respiratory secretions. Inhaled antibiotics offer the theoretical advantage of high local concentrations at the site of infection, with minimal systemic absorption. However, the dose actually delivered to the lung is difficult to control and measure. It is governed by the complex interaction of factors related to nebulizer design and operating conditions, drug formulation, and patient characteristics. Basic principles of aerosols and the variables affecting lung deposition are discussed. Many clinical trials have paid little attention to these variables, making results difficult to interpret. However, recent well-designed studies have shown a benefit to aerosolized tobramycin in reducing the morbidity of cystic fibrosis (CF) lung disease. Inhaled antibiotics have also been investigated in the prophylactic and acute management of Gram-negative nosoco-mial pneumonias in critically ill patients without CF. Clinical trials of aerosolized antibiotics for the management of both CF lung disease and nosocomial pneumonias are reviewed. The data on toxicities and antibiotic resistance are also summarized.