A newborn girl of 27 weeks' gestation was delivered vaginally to a mother with a history of crack cocaine use. The mother, thinking that the infant was stillborn, delayed calling the emergency medical service for 1 hour, while the infant lay unattended.
At admission, the infant was cyanotic, with shallow respirations. Her heart rate was 50 beats per minute. Her trachea was immediately intubated. Her lungs had good air entry and did not demonstrate rales or rhonchi. Her abdomen was soft. Anteroposterior and lateral chest roentgenograms were obtained (Figs 1 and 2).
Denouement and Discussion
In retrocardiac pneumomediastinum, a loculated air collection is located posterior to the heart. The precise location of this air collection is controversial. It has previously been described as pleural air in the inferior pulmonary ligament1,2 and as infra-azygos pneumomediastinum.3 However, air in the pulmonary ligament has been difficult to demonstrate experimentally.
Pollack A, Lask P, Kassner EG, Wood BP. Radiological Cases of the Month. Am J Dis Child. 1992;146(7):831-832. doi:10.1001/archpedi.1992.02160190063020