Pneumomediastinum

Abstract

Pneumomediastinum (PM), or mediastinal emphysema, is defined by the presence of free air in the mediastinal cavity which is anatomically limited by the pleural cavities laterally, diaphragm at the bottom and on the top the thoracic inlet. The entity was first described in 1819, by the French physician Réné Laënnec. PM is divided according to the mechanism of occurrence, related to a clear etiology, into the secondary PM, when there is evidence of a specific cause, and in the absence of an etiology into spontaneous pneumomediastinum (SPM). For SPM, many respiratory and non-respiratory causes were incriminated, as well as traumas and iatrogenic complications. Generally, PM has a benign course, especially in case of SPM, where the conservative treatment is the option. However in secondary PM a number of procedures are necessary to assess the severity of the situation for further management especially when complications occur, such as mediastinitis. In this review we aim to discuss pathophysiology, epidemiology, clinical and radiological findings as well as the causes and management of PM.