Spontaneous Pneumomediastinum: Natural History and Clinical Significance

ABSTRACT

STUDY OBJECTIVE: We evaluate the clinical characteristics and natural history of patients presenting with spontaneous pneumomediastinum (SPNM) . DESIGN: A retrospective case series was conducted to identify patients diagnosed with SPNM. ICD-7(J98.2) discharge codes were used for Jan. 1993 to Aug. 1996 at four institutions , and emergency department(ED) records and admission charts were reviewed. Clinical features, interventions, complications, setting, etiology, symptoms, and length of hospital stay were recorded. PARTICIPANTS: All ED patients more than 12 years old with a diagnosis of SPNM. RESULTS: Thirteen cases were identified. Age range was 14 to 58 years(mean 24 years). Presenting symptoms were chest pain in eight(62%), dyspnea in six(46%), both symptoms in three(23%), no complaints in three(23%). Seven(54%) patients complained only of throat discomfort. Seven(54%) had subcutaneous emphysema, and two(15.3%) had a small pneumothorax. Two(15.3%) were smokers. Three(23%) had normal esophagograms and another three had normal chest CT findings. Two cases(15.3%) were associated with inhalational drug use and three cases were due to exercise. Nine cases(69%) had a history of "Valsalva-type" maneuver. Two patients(15%) had a history of antituberculous treatment and one(7.7.%) had suffered from bronchial asthma. Mean hospital days were 7.3 days(range 3 to 14), none of all needed any intervention. Specifically, no patient developed a subsequent pneumothorax or airway compromise. Seven cases(54%) were received prophylactic antibiotics. CONCLUSION: Most simple SPNM cases are benign disease and most of them(78%) had shown typical chest pain, dyspnea and subcutaneous emphysema. Inhalational drug use is not a main cause of SPNM yet, but increase in use of bronchoinhalers is a suspicous cause of SPNM.