After a right thoracotomy for removal of lung lobes, two chest tubes are attached to a chest drainage system to re-establish negative pleural pressure. Which finding provides the earliest indication that the chest tube may be displaced?

• A. Clear breath sounds bilaterally
• B. Diminished right lower lobe breath sounds
• C. Increased breath sounds on right
• D. No breath sounds on left

Answer: (B)

The main idea is that chest tubes keep negative pleural pressure to re-expand the lung after surgery. If a tube shifts out of place, the lung on that side can begin to collapse again, so air and fluid aren’t being effectively evacuated and the affected lung area loses ventilation first. That early sign shows up as diminished breath sounds over the right lower lobe, indicating reduced air entry in the area that should be expanding with the chest tubes functioning.

Not hearing a problem on the left or hearing normal or increased sounds on the right doesn’t fit displacement because those would point to issues on the other side or to overinflation, not to a tube that’s no longer maintaining the pleural space.