What is the primary purpose of chest tubes in medical treatment?

• A. To deliver medication
• B. To re-establish negative pressure in the pleural space
• C. To drain excessive fluid from the lungs
• D. To assist with oxygenation

Answer: (B)

The primary purpose of chest tubes is to re-establish negative pressure in the pleural space. In the normal physiological state, the pleural cavity has a negative pressure that allows for the proper expansion of the lungs during breathing. When conditions such as pneumothorax (air in the pleural space), hemothorax (blood in the pleural space), or pleural effusion (fluid in the pleural space) occur, this negative pressure can be disrupted, impacting lung expansion and function.

Chest tubes are inserted to remove air, blood, or fluid from the pleural space, effectively reestablishing that negative pressure. This facilitates the re-inflation of the lung and promotes normal respiratory mechanics, enabling the patient to breathe more effectively. By restoring the proper pressure balance, chest tubes play a critical role in treating conditions that compromise lung function.

While delivering medication, draining fluid, or assisting with oxygenation may be relevant in certain contexts, these actions do not directly address the primary function of restoring negative pressure in the pleural cavity, which is essential for adequate lung expansion and respiratory health.