What is the role of the suction chamber in a chest drainage system?

• A. Acts as a one-way valve.
• B. Collects the drainage.
• C. Provides suction to actively evacuate air and fluid from the pleural space.
• D. Measures blood pressure.

Answer: (C)

The suction chamber is where negative pressure is created to actively pull air and fluid out of the pleural space. It connects to regulated suction, and the water column inside this chamber sets a fixed level of suction (for example, around -20 cm H2O). That negative pressure drives drainage through the chest tube, helping the lung re-expand and preventing fluid or air from re-accumulating.

This is different from the water-seal chamber, which functions as a one-way valve to prevent air from flowing back into the chest. The collection chamber simply holds the drainage that exits the pleural space. Measuring blood pressure is not a role of the chest drainage system.