A bronchopleural fistula is a connection from the bronchial tree to the pleural space. Miller cites three ways this can occur:
- rupture of a bronchus, bulla, cyst, or abscess
- erosion due to carcinoma or inflammatory disease
- stump dehiscence status post pneumonectomy
Ventilator management is difficult because
- positive pressure ventilation may lead to tension pneumothorax
- air leak from the fistula can lead to inadequate oxygenation and ventilation
The difference between inhaled and exhaled tidal volumes is one way to measure the size of a fistula.
A chest drain can reduce the chance of tension pneumothorax with PPV.
High frequency jet ventilation with permissive hypercapnia avoids the need for a DLT or SLT with blocker. HFJV avoids barotrauma to the other lung and decreases the air leak.
If high frequency jet ventilation is not available, BP fistula is one of the strict indications for split lung (i.e. DLT) ventilation.