Q: 40 year old male is in ICU after spontaneous pneumothorax four days ago which was successfully drained with thoracostomy (chest tube). Since last night there is no "air leak" despite chest tube on suction. Clamp is applied to chest tube. Patient remained asymptomatic. How long should you wait to repeat CXR and discontinue (pull out) chest tube?


Answer:  At least 12 hours

Ideally, chest tube should be left in clamped position for twelve hours after the lung is fully expanded  on CXR and there is no detectable "air leak" on chest drainage system (aka Pleurovac). Repeat CXR without change  and no clinical symptom in 12 hours after the chest tube is clamped warrants safe removal of tube.