Water should rise and fall in water seal (undulate) with respirations due to pressure changes in pleural space.
If bubbling continues, leak is between clamp and drainage system. If leak stops, air leak is at insertion site. With physician's order, RN places padded clamp closest to dressing. IF the nurse notes that there is CONTINUOUS bubbling in the water seal chamber, check for leaks in the system. Continuous bubbling in the water seal is abnormal and indicates an air leak. Intermittent bubbling in water seal chamber with forced expiration or cough is OK. Bubbles on forceful expiration or coughing, not normal otherwise. Monitor for continuous bubbling in the water seal chamber. The water seal chamber acts as a one-way valve (air goes out, none goes in). The chest drainage system should always be kept below the level of the chest. Tape all connections to ensure they do not become loose.
The insertion site should be covered with airtight dressing-tubes are usually sutured in place. A chest tube to drain fluid or blood will be placed posterior and inferior because fluid will collect in the most dependent part of the pleural space. A chest tube that allows air to escape from the chest will be placed anterior and superior in the chest because air within the pleural space will rise to the highest point in the chest. Tube to drain air is located near apex (top) to drain fluid is located near base (bottom). Prevents air and fluid from returning to the chest