Where should the chest-tube tip ideally reside on imaging?

• A. In the mediastinum.
• B. In the airway.
• C. In the pleural space.
• D. In the lung parenchyma.

Answer: (C)

Chest tubes drain the pleural space, so imaging should show the tip occupying the pleural cavity itself. Being in the pleural space allows air or fluid to be removed effectively, while placements in the mediastinum, airway, or lung parenchyma risk serious injury or fail to drain properly. On radiographs, the distal end should project into the pleural space rather than into lung tissue or beyond into the mediastinum or airway. The exact pleural-space quadrant depends on the indication—apical pleural space for pneumothorax drainage, posterior/basilar space for effusions—but the key idea is that the tip resides in the pleural cavity.