title: Abdominal injuries without hemoperitoneum: a potential limitation of focused abdominal sonography for trauma (FAST)
abstract: BACKGROUND
  Focused abdominal sonography for trauma (FAST) relies on hemoperitoneum to identify patients with injury. Blunt trauma victims (BTVs) with abdominal injury, but without hemoperitoneum, on admission are at risk for missed injury.
  
  
  METHODS
  Clinical, radiologic, and FAST data were collected prospectively on BTVs over a 12-month period. All patients with FAST-negative for hemoperitoneum were further analyzed. Examination findings and associated injuries were evaluated for association with abdominal lesions.
  
  
  RESULTS
  Of 772 BTVs undergoing FAST, 52 (7%) had abdominal injury. Fifteen of 52 (29%) had no hemoperitoneum by admission computed tomographic scan, and all had FAST interpreted as negative. Four patients with splenic injury underwent laparotomy. Six other patients with splenic injury and five patients with hepatic injury were managed nonoperatively. Clinical risk factors significantly associated with abdominal injury in BTVs without hemoperitoneum include: abrasion, contusion, pain, or tenderness in the lower chest or upper abdomen; pulmonary contusion; lower rib fractures; hemo- or pneumothorax; hematuria; pelvic fracture; and thoracolumbar spine fracture.
  
  
  CONCLUSIONS
  Up to 29% of abdominal injuries may be missed if BTVs are evaluated with admission FAST as the sole diagnostic tool. Consideration of examination findings and associated injuries should reduce the risk of missed abdominal injury in BTVs with negative FAST results.
authors.affiliation: Division of Traumatology, R Adams Cowley Shock Trauma Center, University of Maryland Medical System, Baltimore 21201-1595, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: Chiu
authors.forename: B M
authors.initials: BM
authors.lastname: Cushing
authors.forename: A
authors.initials: A
authors.lastname: Rodriguez
authors.forename: S M
authors.initials: SM
authors.lastname: Ho
authors.forename: S E
authors.initials: SE
authors.lastname: Mirvis
authors.forename: K
authors.initials: K
authors.lastname: Shanmuganathan
authors.forename: M
authors.initials: M
authors.lastname: Stein
mesh_terms: D000007:Abdominal Injuries / Q000150:complications / Q000000981:diagnostic imaging*; D000328:Adult; D004636:Emergency Service, Hospital; D005260:Female; D006465:Hemoperitoneum / Q000150:complications / Q000000981:diagnostic imaging*; D006801:Humans; D015994:Incidence; D008297:Male; D008403:Mass Screening; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D014949:Wounds, Nonpenetrating / Q000150:complications / Q000000981:diagnostic imaging*