Bronchoscopic Myths and Legends

Obtaining a diagnosis in patients with new infiltrates, fever, and hypoxemia is a diagnostic challenge. In patients with immunocompromised states or nosocomial infections, knowing the etiologic factor increases the likelihood of successful treatment and avoidance of mechanical ventilation. Performing flexible fiberoptic bronchoscopy has been shown to assist in the diagnosis. However, it is a relative contraindication to perform bronchoscopy in severely hypoxic patients due to increased risk of potentiating respiratory failure. The increased use of noninvasive positive pressure ventilation in these patients was felt to be a performance and safety barrier to bronchoscopy. Therefore, it is thought that flexible fiberoptic bronchoscopy should not be performed in patients with severe hypoxemia requiring noninvasive positive pressure ventilation. Myth: Bronchoscopy should not be performed on severe hypoxemic patients requiring noninvasive positive pressure ventilation due to risk of worsening hypoxemia precipitating mechanical ventilation. Pulmonary complications are an important cause of morbidity and mortality in the immunocompromised host and in patients with nosocomial infections. Flexible fiberoptic bronchoscopy (FFB) has been used increasingly for diagnostic and therapeutics in the last 40 years. Inpatient FFB and bronchoalveolar lavage (BAL) are often used to determine the cause of diffuse interstitial infiltrates and fever.1 Infections, especially in the immunocompromised host, can progress rapidly. This requires a quick evaluation to guide potential therapies. However, many of these patients present with significant hypoxemia. The need for FiO2 greater than 50% or noninvasive positive pressure ventilation (NIPPV) to maintain a PaO2 >=75 mm Hg has been the definition of severe hypoxemia and accepted as a relative contraindication to bronchoscopy by the American Thoracic Society.1,2 There is a large body of evidence that NIPPV is a "safe and effective means of recruiting alveoli and augmenting ventilation."1 Patients, however, are considered too unstable to undergo FFB while receiving NIPPV due to a potential drop of 10 to 20 mm Hg in oxygen tension after a routine bronchoscopy 1 and increased work of breathing because of the bronchoscope in the main trachea. Past options included postponing