title: Defining the percentage of intra-abdominal hemorrhage in abdominal computerized tomography using stereology in patients with blunt liver injury and determining its relationship with outcomes.
abstract: BACKGROUND
  The aim of this study is to determine the percentage of intra-abdominal hemorrhage (PIAH) on computerized tomographic (CT) scan via the Cavalieri method and to define whether this is correlated with the outcome.
  
  
  METHODS
  Fifty-one patients (24 children and 27 adults) with blunt hepatic injury were studied in this Level III prognostic clinical cohort study. The stereologic method of point counting based on the Cavalieri approach was adapted to CT data so as to assess IAH and abdominal volume. PIAH was calculated as intra-abdominal fluid volume/whole abdominal volume × 100.
  
  
  RESULTS
  Mean PIAHs in children and adults were 4.20% ± 2.85% and 6.28% ± 5.21%, respectively. Coexisting intra-abdominal injuries in children and in adults were as follows: splenic injury (29.2, 11.1%; p = 0.012), kidney (25, 11.1%), bladder (4.2, 14.8%), and pelvic fracture (12.5, 11.1%). PIAH was moderately negatively associated with hemoglobin levels (r = -0.301; p = 0.032), hematocrit levels (r = -0.322; p = 0.021), and GCS (Glasgow Coma Scale) score (r = -0.276; p = 0.05). Neither receiver operating characteristic curve analyses for PIAH nor outcomes were statistically significant in children. In adults, sensitivity and specificity of PIAH in predicting the prognoses when the cutoff levels were taken as 5.39%, 9.9%, and 12.4%, respectively, were as follows: operation (71, 84%), mortality (36, 93%), and intensive care unit admission (25, 94%).
  
  
  CONCLUSIONS
  In patients with blunt hepatic injury, the Cavalieri principle of stereology can easily be added to the CT slices to calculate PIAH. This method is repeatable in other institutions and can be used as a guide to predict outcomes. It is suitable for a universal parameter to measure intra-abdominal fluid in blunt injury. PIAH has low sensitivity but high specificity to predict intensive care unit admission and mortality in cases of blunt hepatic injury in adults. Its specificity in predicting the need for operation is better than that of the anatomic liver injury grading systems in computerized tomography.
  
  
  METHODS
  Prognostic study, level III.
authors.affiliation: Department of Emergency Medicine, Medical Faculty, Ataturk University, Erzurum, Turkey. mustafauzkeser@gmail.com
authors.forename: Mustafa
authors.initials: M
authors.lastname: Uzkeser
authors.forename: Huseyin
authors.initials: H
authors.lastname: Sahin
authors.forename: Bunyami
authors.initials: B
authors.lastname: Ozogul
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Cayir
authors.forename: Fatih
authors.initials: F
authors.lastname: Alper
authors.forename: Mucahit
authors.initials: M
authors.lastname: Emet
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006470:Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging* / Q000293:injuries*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011860:Radiography, Abdominal; D014057:Tomography, X-Ray Computed; D014949:Wounds, Nonpenetrating / Q000000981:diagnostic imaging*; D055815:Young Adult