title: Predicting proper endotracheal tube placement in underexposed radiographs: tangent line of the aortic arch.
abstract: OBJECTIVE
  We investigated an indirect radiographic means of predicting proper endotracheal tube placement on underexposed portable chest radiographs.
  
  
  CONCLUSIONS
  When an endotracheal tube is 3.4-5.0 cm above the tangent line of the aortic arch, it is in proper position 95% of the time.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: J N
authors.initials: JN
authors.lastname: Pappas
authors.forename: P C
authors.initials: PC
authors.lastname: Goodman
mesh_terms: D000328:Adult; D000368:Aged; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging*; D003422:Critical Care; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D019095:Point-of-Care Systems; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D013679:Technology, Radiologic