Which finding would indicate an abnormal air leak in the chest tube water-seal chamber?

• A. Intermittent bubbling with respirations
• B. No bubbling
• C. Continuous bubbling in the water-seal chamber
• D. Drainage minimal

Answer: (C)

In a chest-tube system with a water-seal chamber, air movement through the chamber is what you monitor. The water-seal acts like a one-way valve and shows activity as the lung expands and contracts. Continuous bubbling in the water-seal chamber means air is constantly escaping from the pleural space into the drainage system, which is an abnormal air leak. This points to a persistent leak somewhere in the chest tube setup or the lung itself. By contrast, intermittent bubbling with breathing can be a normal tidaling pattern or reflect a small, nonpersistent leak, and no bubbling suggests the leak has ceased or the system is currently not allowing air to escape. Drainage being minimal relates to fluid output and does not indicate the presence or absence of an air leak.