Pneumomediastinum

• Abnormal finding of air contained within the mediastinum
• Etiologies include
  • Alveolar rupture, from asthma, mechanical ventilation, diving barotrauma, smoking, or spontaneous
  • Thoracic trauma, including blunt trauma and penetrating injuries
  • Other causes, including bronchial or tracheal rupture, laryngeal trauma, esophageal rupture, mediastinal infection, retroperitoneal process (including post-surgery or perforated viscus), and facial trauma or fracture