A. Hemoptysis.

1. To localize the bleeding site and diagnose its cause.

2. Greater sensitivity within 48 hours of time of active bleeding (34% to 91%) versus delayed (11% to 52%).

3. Rigid bronchoscopy preferred if massive hemoptysis to stabilize the airway.

B. Atelectasis. When chronic: to rule out endobronchial obstruction by malignancy or foreign body. When acute, mucus plugging is most common.

C. Diffuse parenchymal disease.

1. Transbronchial lung biopsy and bronchoalveolar lavage (BAL) can offer information about parenchymal processes. Highest yield in diagnosing sarcoidosis, lymphangitic carcinomatosis, or eosinophilic pneumonia.

2. Rarely provides definitive diagnosis for pulmonary vasculitis or to classify pulmonary fibrosis.

3. BAL is an aid for diagnosing opportunistic infections in the immunocompromised host.

4. Lung biopsy with fluoroscopy can improve localization and minimize pneumothorax risk.

D. Diagnosis of ventilator-associated pneumonia (VAP).

1. Threshold values: >10⁴ colony forming units (cfu)/mL for BAL and >10³ cfu/mL for protected specimen brush (PSB).

2. Performance characteristics.

a. BAL: sensitivity 73%, specificity 82%.

b. PSB: median sensitivity 67%, specificity 95%.

3. Blind telescoping catheters have similar performance.

4. Colony counts change rapidly within 12 hours of initiating antibiotic therapy; 50% of significant species drop to below diagnostic threshold.

5. Prospective randomized trials have not demonstrated improvement in mortality, intensive care unit (ICU) stay, or duration of mechanical ventilation with routine early bronchoscopy strategy.

6. Purulent secretions surging from distal bronchi during exhalation may be predictive of VAP.

E. Acute inhalation injury.

1. To identify the anatomic level and severity of injury after smoke inhalation.

2. Upper airway obstruction may develop within 24 hours of inhalation injury.

3. Acute respiratory failure is more likely with mucosal change at segmental or lower levels.

F. Blunt chest trauma. To rule out airway fracture after blunt trauma, suggested by hemoptysis, lobar atelectasis, pneumomediastinum, or pneumothorax.

G. Assessment of intubation-related trauma. To assess laryngeal or tracheal damage from endotracheal tubes.

H. Pulmonary infiltrates in immunocompromised patients.

1. Diagnostic yield of BAL is 50% and leads to change of treatment in 17% to 38%.

2. Transbronchial biopsy has small incremental yield, 7% to 12%, with significant complication rate. Yield may be higher in HIV patients.

A. Excessive secretions/atelectasis.

1. Lobar atelectasis not responding to chest physical therapy, incentive spirometry, and cough.

2. Instillation of N-acetylcysteine (NAC), surfactant, and recombinant DNase have been utilized to help liquefy inspissated mucus. No clinical trials clearly support their routine use.

B. Foreign bodies.

1. Rigid bronchoscopy is the procedure of choice to remove aspirated foreign bodies.

2. Devices are available to help remove foreign bodies with the flexible scope.

C. Endotracheal intubation. Bronchoscope can be used as obturator allowing fiberoptically guided intubation.