Have you ever had a patient with a chest tube and you notice new continuous noisy or turbulent bubbling in the water seal chamber? A leak may be present, but first check that all connections are tight and secure. Clamp the chest tube at the insertion site (or closest to the dressing) using padded clamps and reassess the water chamber. If the bubbling stops, the leak is probably caused by patient air leak into the pleural space (in the lung) or at the insertion site. Unclamp immediately. Never clamp the chest tube for more than a few seconds or you risk a tension pneumothorax.  

If the bubbling does not stop, reclamp the chest tube with padded clamps just a few inches distal to the insertion site and reassess the bubbling in the chamber to attempt to locate the air leak. Remember to only clamp the chest tube for a few seconds at a time. If the bubbling stops close when the chest tube is clamped close to a connection, you may be able to reseal the connection and fix the problem. If you clamp the system all the way from the patient to chamber and still have bubbling in the water seal chamber, the entire system may need to be changed.

Check out this video at 2:45 for visual demonstration: https://www.youtube.com/watch?v=Ui0eKmEk38M

Hazinski, M.F. (2013). Nursing Care of the Critically Ill Child. 3rd ed. St. Louis, MO: Mosby/Elsevier