Pneumomediastinum: etiology and a guide to diagnosis and treatment.

BACKGROUND: Pneumomediastinum may be associated with mediastinal organ injury. The aim of this study was to identify predictive factors of mediastinal organ injury in patients with pneumomediastinum to guide diagnosis and treatment.

METHODS: A retrospective review was conducted including patients aged ≥18 years with Current Procedural Terminology code 518.1 (interstitial emphysema) from 2005-2011.

RESULTS: There were 279 of 343 patients (81%) with and 64 of 343 (19%) without history of trauma. In the trauma population, 13 patients (5%) were found to have mediastinal organ injuries, 10 (4%) had airway injuries, and 3 (1%) had esophageal injuries. In the nontrauma population, 36 patients (56%) had spontaneous pneumomediastinum, esophageal injuries were seen in 17 (27%), pneumothorax in 9 (14%), and airway injuries in 2 (3%). The predictors of esophageal injury were instrumentation (odds ratio [OR], 45.7; P < .0001), pleural effusion (OR, 10.5; P < .0001), and vomiting (OR, 9.3; P < .0001). Previous instrumentation was the most significant predictor of airway injury (OR, 9.05; P < .02).

CONCLUSIONS: Mediastinal organ injury in patients with pneumomediastinum is uncommon. Patients presenting with pneumomediastinum without a history of instrumentation, pleural effusion, or vomiting most commonly do not have mediastinal organ injuries.