title: Spontaneous pneumomediastinum and subcutaneous emphysema in asthma exacerbation: The Macklin effect.
abstract: OBJECTIVE
  We describe the clinical features of a 17-year-old girl with severe asthma exacerbations. On admission to the intensive care unit, she manifested expiratory dyspnea, cyanosis, and an unproductive cough. Her chest x-rays showed extensive pneumomediastinum (PM), mild subcutaneous emphysema at the right anterior triangle of the neck, and right upper-lobe atelectasis. Her PM resulted from the "Macklin effect," which involves a three-step process: overly distended alveolar rupture, air dissection along the bronchovascular sheaths, and air spreading into the mediastinum.
  
  
  METHODS
  Treatment consisted of oxygen therapy, parenteral corticosteroids, and nebulized bronchodilators.
  
  
  RESULTS
  She made a good recovery, and was discharged from the intensive care unit after 2 days.
  
  
  CONCLUSIONS
  This case illustrates that conservative management strategies in this severe and unusual complication of asthma exacerbation can result in rapid and complete recovery. Nonetheless, every asthma exacerbation should be considered potentially life-threatening, and must be treated promptly and adequately.
authors.affiliation: Respiratory Care Department, Instituto Médico La Floresta, Caracas, Venezuela.
authors.forename: Kleber J
authors.initials: KJ
authors.lastname: Romero
authors.forename: Máximo H
authors.initials: MH
authors.lastname: Trujillo
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D001249:Asthma / Q000150:complications* / Q000188:drug therapy / Q000628:therapy; D001784:Blood Gas Analysis; D001993:Bronchodilator Agents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D010102:Oxygen Inhalation Therapy; D011027:Pneumoperitoneum / Q000188:drug therapy / Q000209:etiology* / Q000628:therapy; D001261:Pulmonary Atelectasis / Q000188:drug therapy / Q000209:etiology* / Q000628:therapy; D012307:Risk Factors; D013352:Subcutaneous Emphysema / Q000188:drug therapy / Q000209:etiology* / Q000628:therapy; D013997:Time Factors
chemical_list: D000305:Adrenal Cortex Hormones; D001993:Bronchodilator Agents