Spontaneous pneumomediastinum: experience in 18 patients during the last 12 years

OBJECTIVE: To characterize clinically all of the patients with spontaneous pneumomediastinum (SPM) admitted to an adult pulmonology ward in Lisbon, Portugal. METHODS: This was a retrospective descriptive study of all adult patients (≥ 18 years of age) diagnosed with SPM between January of 2004 and September of 2015. RESULTS: At least one predisposing factor was identified in most (88.9%) of the 18 patients who presented with SPM during the study period. With regard to precipitating factors, bouts of cough were present in 50.0% of the patients. Other precipitating factors included a sudden increase in tobacco consumption, inhaled drug use, occupational inhalation of varnish fumes, intense exercise, and vomiting. The most common complaints were dyspnea (in 83.3%) and chest pain (in 77.8%). Other complaints included cough, neck pain, dysphagia, and odynophagia. Subcutaneous emphysema was found in most of the patients. The diagnosis of SPM was based on chest X-ray findings in 61.1% of the patients. CONCLUSIONS: Although SPM is a rare condition, it should be considered in the differential diagnosis of chest pain and dyspnea. It can develop without a triggering event or conclusive findings on a chest X-ray, which is usually sufficient for diagnosis.