Abstract
The occurrence of interstitial emphysema of the lung with air within the mediastinum as a result of thoracic trauma has been recognized for a long time. It has, of course, been described by many observers following medical and surgical maneuvers involving the lungs and pleura and associated with foreign bodies in the bronchial tree. The occurrence of mediastinal air and subcutaneous air has also been described as a complication of many pulmonary diseases, including tuberculosis, influenza, bronchopneumonia of various types and asthma. It has been known to occur when the intrabronchial pressures were elevated by the use of positive pressure anesthesia and during the efforts of labor. Hamman,1however, was the first to report the condition in healthy persons without antecedent trauma or disease. It was in 1934, in a paper discussing the diagnosis of coronary occlusion, that Hamman presented2cases of spontaneous mediastinal emphysema which simulated coronary

This publication has 3 references indexed in Scilit: