mediastinal emphysema

Last reviewed 01/2018

Air in the mediastinum.

Most common cause is rupture of the alveoli (air then enters the interstitial tissues and tracks to the mediastinum). Causes include:

  • raised intrapulmonary pressures e.g. vomiting, asthma, coughing
  • positive pressure mechanical ventilation

Other causes include:

  • penetrating neck injury
  • oesophageal and bronchial rupture

Clinical features:

  • may be asymptomatic
  • chest pain that is worse on swallowing or breathing
  • crunching sound coincident with each heart beat

Chest X-ray:

  • air in the upper mediastinum, around the heart, or within the soft tissues of the neck
  • pneumothorax in 30% of cases

Treatment:

  • treat underlying cause
  • treatment with high concentration inspiratory oxygen can hasten resolution