title: Spontaneous pneumomediastinum: clinical and natural history.
abstract: OBJECTIVE
  To evaluate the clinical characteristics and natural history of patients presenting with spontaneous pneumomediastinum.
  
  
  METHODS
  A retrospective case series was conducted to identify patients diagnosed with spontaneous pneumomediastinum. ICD-9 discharge codes were used for 1984 to 1990 at two institutions, and emergency department records of a third hospital were reviewed for 1981 to 1986. Clinical features, interventions, complications, setting, etiology, symptoms, and length of hospital stay were recorded.
  
  
  METHODS
  Three university tertiary care hospitals.
  
  
  METHODS
  All ED patients more than 12 years old with a diagnosis of spontaneous pneumomediastinum.
  
  
  METHODS
  None.
  
  
  RESULTS
  Seventeen cases were identified. Age range was 15 to 41 years (mean, 25 years). Presenting symptoms were chest pain in eight (47%), dyspnea in three (18%), both symptoms in three (18%), and neither in three (18%). Three patients complained only of throat discomfort. Nine (52%) had a Hamman's crunch, 11 (65%) had subcutaneous emphysema, and two (11%) had a small pneumothorax. Five (29%) were smokers, and five (29%) had normal esophograms. Thirteen of 17 (76%) cases were associated with illicit inhalation drug use. Twelve cases (70%) had history of a "Valsalva-type" maneuver. All but three were admitted to a hospital, with a mean stay of 2.5 days (range, one to six). No patient suffered complications or required interventions for spontaneous pneumomediastinum. Specifically, no patient developed a subsequent pneumothorax or airway compromise. The three patients not admitted were followed up by telephone contact. All did well with rapid resolution of their symptoms.
  
  
  CONCLUSIONS
  Most spontaneous pneumomediastinum cases occur in the setting of inhalational drug use. One hundred percent of patients will have a symptom directly related to the spontaneous pneumomediastinum, with 82% presenting with either dyspnea or chest pain. Most (88%) will present with either subcutaneous emphysema or a Hamman's crunch on examination. Simple spontaneous pneumomediastinum has a very benign course and does not require hospitalization. Serial radiographs, likewise, did not change the medical management of spontaneous pneumomediastinum.
authors.affiliation: Department of Emergency Medicine, University Hospitals of Cleveland, Ohio.
authors.forename: E A
authors.initials: EA
authors.lastname: Panacek
authors.forename: A J
authors.initials: AJ
authors.lastname: Singer
authors.forename: B W
authors.initials: BW
authors.lastname: Sherman
authors.forename: A
authors.initials: A
authors.lastname: Prescott
authors.forename: W F
authors.initials: WF
authors.lastname: Rutherford
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D001314:Auscultation; D002637:Chest Pain / Q000209:etiology; D004417:Dyspnea / Q000209:etiology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D013287:Illicit Drugs / Q000009:adverse effects*; D008297:Male; D008478:Mediastinal Emphysema / Q000150:complications / Q000175:diagnosis / Q000209:etiology*; D012189:Retrospective Studies; D013352:Subcutaneous Emphysema / Q000150:complications
chemical_list: D013287:Illicit Drugs