title: Computed Tomographic Findings and Mortality in Patients With Pneumomediastinum From Blunt Trauma.
abstract: OBJECTIVE
  The care of most patients with pneumomediastinum (PNM) due to trauma can be managed conservatively; however, owing to aerodigestive tract injury and other associated injuries, there is a subset of patients with PNM who are at higher risk of mortality but can be difficult to identify.
  
  
  OBJECTIVE
  To characterize computed tomographic (CT) findings associated with mortality in patients with PNM due to blunt trauma.
  
  
  METHODS
  A retrospective review of medical records from January 1, 2002, to December 31, 2011, was conducted at a university-based urban trauma center. The patients evaluated were those injured by blunt trauma and found to have PNM on initial chest CT scanning. Data analysis was performed July 2, 2013, to June 18, 2014.
  
  
  METHODS
  In-hospital mortality.
  
  
  RESULTS
  During the study period, 3327 patients with blunt trauma underwent chest CT. Of these, 72 patients (2.2%) had PNM. Patients with PNM had higher Injury Severity Scores (P < .001) and chest Abbreviated Injury Scale scores (P < .001) compared with those without PNM. Pneumomediastinum was associated with higher mortality (9 [12.5%] vs 118 [3.6%] patients; P < .001) and longer mean (SD) hospital stays (11.3 [14.6] vs 5.1 [8.8] days; P < .001), intensive care unit stays (5.4 [10.2] vs 1.8 [5.7] days; P < .001), and ventilator days (1.7 [4.2] vs 0.6 [4.0] days; P < .03). We evaluated several chest CT findings that may have predictive value. Pneumomediastinum size was not associated with in-hospital mortality (P = .22). However, location of air in the posterior mediastinum was associated with increased mortality of 25% (7 of 28 patients; P = .007). Air in all mediastinal compartments was also associated with increased mortality of 40.0% (4 of 10 patients; P = .01). Presence of hemothorax along with PNM was associated with mortality of 22.2% (8 of 36 patients; P = .01).
  
  
  CONCLUSIONS
  Pneumomediastinum is uncommon in patients with injury from blunt trauma; however, CT findings of posterior PNM, air in all mediastinal compartments, and concurrent hemothorax are associated with increased mortality. These CT findings could be used as a triage tool to alert the trauma surgeon to a potentially lethal injury.
authors.affiliation: Department of Surgery, University of California, San Francisco-East Bay, Oakland.
authors.forename: Wayne S
authors.initials: WS
authors.lastname: Lee
authors.affiliation: Department of Surgery, University of California, San Francisco-East Bay, Oakland.
authors.forename: Vincent E
authors.initials: VE
authors.lastname: Chong
authors.affiliation: Department of Surgery, University of California, San Francisco-East Bay, Oakland.
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Victorino
mesh_terms: D000328:Adult; D017052:Hospital Mortality; D006801:Humans; D008478:Mediastinal Emphysema / Q000000981:diagnostic imaging* / Q000209:etiology / Q000401:mortality*; D008875:Middle Aged; D012189:Retrospective Studies; D013898:Thoracic Injuries / Q000150:complications / Q000000981:diagnostic imaging / Q000401:mortality; D014057:Tomography, X-Ray Computed; D014949:Wounds, Nonpenetrating / Q000150:complications / Q000000981:diagnostic imaging / Q000401:mortality; D055815:Young Adult