Saunders Respiratory Practice

Which observation suggests that a chest tube is functioning correctly?

1. The drainage system is placed above the client's chest

2. Fluctuation of water in the water-seal chamber

3. Constant level in the drainage-collection chamber

4. The dressing over the insertion site is loose

The correct answer is: Fluctuation of water in the water-seal chamber

Fluctuation of water in the water-seal chamber indicates that the chest tube is functioning correctly. This fluctuation, often referred to as "tidaling," occurs with changes in intrathoracic pressure during breathing. When the patient inhales, the chest expands, and the water level in the chamber rises. When the patient exhales, the pressure decreases, causing the water level to lower. Observing this fluctuation is a sign that the chest tube is effectively draining fluid or air from the pleural space and that the system is functioning as intended. In contrast, the other observations provide different implications about the chest tube's functioning. If the drainage system is placed above the client's chest, it may lead to improper drainage, as gravity assists with fluid evacuation. A constant level in the drainage-collection chamber might indicate the absence of drainage, which could signify a blockage or that the tube is not functioning effectively. Lastly, a loose dressing over the insertion site poses a risk for air entry and potential infection, indicating compromised function of the chest tube system.