ABSTRACT
Trapped lung is one of the outcomes of fibrinous or granulomatous pleuritis and is
a cause of chronic, benign, unilateral pleural effusion. It is characterized by inability
of the lung to expand and fill the thoracic cavity due to a restricting fibrous visceral
pleural peel. The resulting chronic pleural space is fluid filled, and the persistence
of the fluid is solely due to hydrostatic equilibrium. Historically recognized as
a complication of therapeutic pneumothorax for treatment of tuberculosis, it is today
most commonly a consequence of inadequately treated parapneumonic effusion, but it
is also associated with cardiac surgery, chest trauma, and other inflammatory processes
involving the pleura. The diagnosis requires documentation of chronicity and stability
and the absence of an active inflammatory or malignant pleural process, bronchial
obstruction, or severe underlying lung disease. Findings supporting the diagnosis
are an initial negative pleural liquid pressure, increased pleural space elastance,
and the demonstration of a pleural peel. Confirmation of the diagnosis requires successful
surgical decortication, which is the only available therapy. In the asymptomatic patient,
decortication is not indicated and observation is warranted.
KEYWORD
Trapped lung - pleural pressure - pleural space elastance - decortication
