Thoracentesis and Chest Tubes

The pleural cavity is a negative-pressure airtight space that serves as the interface between the lung and the chest wall. Fluid is produced normally by the parietal pleura and absorbed by the visceral pleura as a result of difference in capillary pressure. The fluid is subsequently absorbed by the pleural lymphatics and ultimately into the thoracic duct. Disruption of the pleural space can result in a pneumothorax (air) or a pleural effusion (fluid). Pleural effusions can be caused by blood (hemothorax), infection (parapneumoic effusion or empyema), chyle (chylothorax), malignancy, inflammatory conditions, or imbalances in hydrostatic and oncotic pressures. Both types of pleural processes alter the negative pressure of the thorax. The resulting positive pressure causes partial or complete lung collapse and respiratory symptoms. Thoracentesis and chest tube placement are essential procedures for both diagnosis and treatment of pleural conditions.