Question

The nurse provides which information about the water-seal chamber on a chest drainage unit (CDU) when educating a group of nursing students?

A. It contains 2 cm of water.
B. It acts as a two-way valve.
C. It receives fluid and air from the pleural space.
D. It applies suction to the chest drainage system.

Answer 1

The water-seal chamber in a chest drainage unit receives fluid and air from the pleural space and prevents re-entry of air, preserving the negative pressure essential for lung inflation.

Step-by-step explanation:

The water-seal chamber of a chest drainage unit (CDU) primarily acts as a one-way valve, allowing air and fluid to exit the pleural space without re-entering. The correct information to provide when educating nursing students is that it receives fluid and air from the pleural space, represented by option C. The lung's surface tension and the negative pressure within the pleural space are crucial for keeping the lungs inflated. If air enters the pleural space, this negative pressure is compromised, potentially resulting in lung collapse. The water-seal chamber in the CDU helps to prevent air from re-entering the pleural space while allowing existing air and fluid to be safely removed.