Which statement about a closed-chest drainage system is correct?

A closed-chest drainage system, commonly used for managing pleural effusions, pneumothorax, or hemothorax, typically relies on a wet suction mechanism to create the necessary suction for effective drainage. In this system, a water-seal chamber is utilized along with a suction control chamber filled with sterile water. The height of the water column in the suction chamber determines the level of suction applied, which facilitates the removal of air or fluid from the pleural space.

This mechanism is essential for maintaining negative pressure, allowing for lung re-expansion and preventing any backflow of fluid or air into the pleural cavity. The use of suction enhances drainage efficiency compared to reliance solely on gravity, especially in cases where fluid is located in deeper areas or when the patient is in various positions.

Contextually, other statements do not accurately reflect the function of closed-chest drainage systems. While gravity can play a role in drainage, it is not the only mechanism; the system primarily utilizes negative pressure generated by suction. High pressure is not employed in this context since the goal is to maintain a negative pressure environment. Additionally, closed-chest drainage systems are not limited to lung infections but are utilized for a variety of conditions involving pleural space management.