title: Pulmonary embolism without deep venous thrombosis: De novo or missed deep venous thrombosis?
abstract: BACKGROUND
  Pulmonary embolus (PE) is thought to arise from a deep venous thrombosis (DVT). Recent data suggest that PE can present without DVT, inferring that PE can originate de novo (DNPE). We examined the relationship between DVT and PE in trauma patients screened for DVT with duplex sonography (DS). We sought to validate the incidence of PE without evidence of DVT and to examine the clinical significance of this entity.
  
  
  METHODS
  We reviewed the medical records of all trauma patients from July 2006 to December 2011 with PE who also had serial surveillance DS (groin to ankle). Demographics, severity of injury, interventions, signs and symptoms of PE, as well as chest computerized tomography findings were collected. Patients with no DS evidence of DVT either before or within 48 hours of PE diagnosis (DNPE) were compared with those with DVT (PE + DVT).
  
  
  RESULTS
  Of 11,330 patients evaluated by the trauma service, 2,881 patients received at least one DS. PE occurred in 31 of these patients (1.08%): 19 (61%) were DNPE, and 12 (39%) were PE + DVT. Compared with patients with PE + DVT, patients with DNPE were significantly younger and had more rib fractures, pulmonary contusions, infections, pulmonary symptoms, and peripherally located PEs on computerized tomography.
  
  
  CONCLUSIONS
  This is the first report of the clinical course of DNPE without embolic origin in a population with comprehensive duplex surveillance. In our series, DNPE seems to be more prevalent after trauma, to be clinically distinct from PE following DVT, and to likely represent a local response to injury or inflammation; however, further research is warranted to fully understand the pathophysiology of DNPE.
  
  
  METHODS
  Care management study, level III.
authors.affiliation: From the Trauma Service, Scripps Mercy Hospital, San Diego, California.
authors.forename: Jan-Michael
authors.initials: JM
authors.lastname: Van Gent
authors.forename: Ashley L
authors.initials: AL
authors.lastname: Zander
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Olson
authors.forename: Steven R
authors.initials: SR
authors.lastname: Shackford
authors.forename: Casey E
authors.initials: CE
authors.lastname: Dunne
authors.forename: C Beth
authors.initials: CB
authors.lastname: Sise
authors.forename: Jayraan
authors.initials: J
authors.lastname: Badiee
authors.forename: Mark S
authors.initials: MS
authors.lastname: Schechter
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Sise
mesh_terms: D000328:Adult; D000925:Anticoagulants / Q000627:therapeutic use; D015984:Causality; D015331:Cohort Studies; D015897:Comorbidity; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods; D014193:Trauma Centers; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods; D020246:Venous Thrombosis / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D014947:Wounds and Injuries / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy
chemical_list: D000925:Anticoagulants