Which statement is true regarding pneumothorax?

Tracheal tug is an abnormal downward movement of the trachea during systole that indicates an aneurysm of the aoic arch. Pneumothorax shows hyper-resonance to percussion, and absent breath sounds Tension pneumothorax must be treated as a medical emergency. A large-bore needle should be inseed into the pleural space through the second anterior intercostal space. If large amounts of gas escape from the needle after inseion, the diagnosis is confirmed. The needle should be left in place until a thoracostomy tube can be inseed.