title: Sonographic assessment of blunt abdominal trauma: a 4-year prospective study.
abstract: OBJECTIVE
  Emergency abdominal sonography has become a common modality worldwide in the evaluation of injuries caused by blunt trauma. The sensitivity of sonography in the detection of hemoperitoneum varies, and little is known about the accuracy of sonography in the detection of injuries to specific organs. The purpose of this study was to determine the overall accuracy of sonography in the detection of hemoperitoneum and solid-organ injury caused by blunt trauma.
  
  
  METHODS
  From January 1995 to October 1998, 3,264 patients underwent emergency sonography at our institution to evaluate for free fluid and parenchymal abnormalities of specific organs caused by blunt trauma. All patients with intra-abdominal injuries (IAIs) were identified, and their sonographic findings were compared with their CT and operative findings, as well as their clinical outcomes.
  
  
  RESULTS
  Three hundred ninety-six (12%) of the 3,264 patients had IAIs. Sonography detected free fluid presumed to represent hemoperitoneum in 288 patients (9%). The sonographic detection of free fluid alone had a 60% sensitivity, 98% specificity, 82% positive predictive value, and 95% negative predictive value for diagnosing IAI. The accuracy was 94%. Seventy patients (2%) had parenchymal abnormalities identified with sonography that corresponded to actual organ injuries. The sensitivity of the sonographic detection of free fluid and/or parenchymal abnormalities in diagnosing IAI was 67%.
  
  
  CONCLUSIONS
  Emergency sonography to evaluate patients for injury caused by blunt trauma is highly accurate and specific. The sonographic detection of free fluid is only moderately sensitive for diagnosing IAI, but the combination of free fluid and/or a parenchymal abnormality is more sensitive.
authors.affiliation: Division of Emergency Medicine, University of California, Davis Medical Center, 2315 Stockton Boulevard, Sacramento, California 95817, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Richards
authors.forename: Nicole H
authors.initials: NH
authors.lastname: Schleper
authors.forename: Brian D
authors.initials: BD
authors.lastname: Woo
authors.forename: Paul A
authors.initials: PA
authors.lastname: Bohnen
authors.forename: John P
authors.initials: JP
authors.lastname: McGahan
mesh_terms: D000007:Abdominal Injuries / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000601:surgery; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D004630:Emergencies; D006465:Hemoperitoneum / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D014949:Wounds, Nonpenetrating / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000601:surgery