Complications from aerodigestive tract foreign bodies result from both the type of foreign body and the duration of entrapment. Objects such as button batteries can cause mucosal erosion in as little 6 hours from the time of ingestion. The risk for complications increases with the duration of time the foreign body remains in place. The initial complications from a laryngeal or bronchial foreign body can be severe, including cyanosis, respiratory distress, and even respiratory arrest and death. A ball-valve effect can occur with a partially occluding bronchial foreign body causing hyperexpansion of the affected lung. If complete bronchial occlusion is present, total or partial lung collapse can occur. Late complications of bronchial foreign bodies include granulation tissue formation, pneumonia, empyema, bronchial fistula, and pneumothorax. In the case of esophageal foreign bodies, late complications include granulation tissue formation, mucosal erosions, esophageal perforation, tracheoesophageal fistula, esophageal-aortic fistula, and mediastinitis.