title: Pneumothorax ex-vacuo or "trapped lung" in the setting of hepatic hydrothorax.
abstract: BACKGROUND
  Hepatic hydrothorax is a major pulmonary complication of liver disease occurring in up to 5-10% of patients with cirrhosis.
  
  
  METHODS
  We report four observations of the development of pneumothorax ex-vacuo or trapped lung in the setting of hepatic hydrothorax. The diagnosis of trapped lung was made based on the presence of a hydropneumothorax after evacuation of a longstanding hepatic hydrothorax with failure of the lung to re-expand after chest tube placement in three of the four cases. Two patients underwent surgical decortication with one subsequent death from post-operative bleeding. The other two patients remarkably had spontaneous improvement of their "trapped lung" without surgical intervention.
  
  
  CONCLUSIONS
  While pneumothorax ex-vacuo is a known phenomenon in malignant effusions, to our knowledge, it has never been described in association with hepatic hydrothoraces. The pathophysiology of this phenomenon remains unclear but could be related to chronic inflammation with development of a fibrous layer along the visceral pleura.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine, David Geffen School of Medicine at University of California, 10833 Le Conte Ave, Room 37-131 CHS, Los Angeles, CA 90095, USA. ykim@mednet.ucla.edu
authors.forename: Yan S
authors.initials: YS
authors.lastname: Kim
authors.forename: Irawan
authors.initials: I
authors.lastname: Susanto
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Lazar
authors.forename: Ali
authors.initials: A
authors.lastname: Zarrinpar
authors.forename: Patricia
authors.initials: P
authors.lastname: Eshaghian
authors.forename: M Iain
authors.initials: MI
authors.lastname: Smith
authors.forename: Ronald
authors.initials: R
authors.lastname: Busuttil
authors.forename: Tisha S
authors.initials: TS
authors.lastname: Wang
mesh_terms: D000368:Aged; D015505:Chest Tubes; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D006876:Hydrothorax / Q000150:complications*; D008107:Liver Diseases / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011030:Pneumothorax / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000628:therapy; D013902:Radiography, Thoracic; D019616:Thoracic Surgical Procedures; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult