Retrocardiac Pneumomediastinum: Radiographic Finding and Clinical Implications

Abstract

Fourteen neonates with posterior mediastinal air collections (retrocardiac pneumomediastinum) are described. In the majority of the infants (13 of 14), the mediastinal air developed as a complication of assisted ventilation. It is suggested that the retrocardiac pneumomediastinum represents air trapped in a potential space in the mediastinum posterior to the heart and not within the pulmonary ligament. The collections have a variable shape and size and rarely may produce a tension phenomenon elevating the posterior, inferior portion of the heart off of the diaphragm. There was a strong association of retrocardiac pneumomediastinum with other manifestations of extraalveolar air, including pulmonary interstitial emphysema (13 of 14 infants), pneumothorax (1 of 14 infants), dissection of air into the soft tissues of the neck (10 of 14 infants), and pneumoperitoneum (5 of 14 infants).

Retrocardiac Pneumomediastinum: Description of an Unusual Case and Review of Literature

“…While cases of generic pneumomediastinum in young ages are widely described in the literature, we cannot say the same for the retrocardiac one, for which few and old manuscripts are reported. Indeed, the search on Pubmed using a keyword such as “retrocardiac OR posterior pneumomediastinum”; the limits of age, “birth—23 months”; and English language led to 5 results, while the search carried out with a keyword such as “pneumomediastinum” and the same limits led to 762 results, among which, 10 papers described retrocardiac pneumomediastinum [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ].…”

“…In all cases that are summarized in Table 1 , the RP occurred in the neonatal period [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ].…”

“…Invasive mechanical ventilation was considered as the primary cause of RP in eight papers [ 11 , 12 , 13 , 16 , 18 , 19 , 20 , 21 ], although Rosenfeld et al reported other conditions such as hyaline membrane disease (HDM), hypoplastic lung (HL), and meconium aspiration (MA) as causes of RP in neonates [ 16 ].…”

“…Most of the cases of RP reported in Table 1 described symptomatic leaks with frequent respiratory distress, which habitually resolved spontaneously [ 11 , 12 , 13 , 14 , 16 , 18 , 19 , 20 , 21 ]. Nevertheless, progressive air collection in the posterior mediastinum has also caused life-threatening situations such as cardiac tamponade [ 19 , 21 ] that required a prompt intervention with surgical drainage.…”

Posteriores Pneumomediastinum – Blickdiagnose einer seltenen Manifestation extraalveolärer Luft

“…Pneumomediastinum und posteriores Pneumomediastinum, 3 Stunden später Pneumothorax links, Intubation und Anlage Pleuradrainage links. Extubation Lebenstag 5, unkomplizierter weitere Verlauf 1 2 .…”