title: Predicting the need for abdominal hemorrhage control in major pelvic fracture patients: the importance of quantifying the amount of free fluid.
abstract: BACKGROUND
  In our institution, the computed tomographic (CT) scan has largely replaced the ultrasound for the rapid detection of intraperitoneal free fluid (FF) and abdominal injuries in severely injured patients.We hypothesized that in major pelvic fracture patients, quantifying the size of FF on CT improves the predictive value for the need for abdominal hemorrhage control (AHC).
  
  
  METHODS
  The CT scans of major pelvic fracture (pelvic ring disruption) patients (January 1, 2004, to June 31, 2012) were reviewed for the presence of FF (small, moderate, or large amount) and abdominal injuries. AHC was defined as requiring a surgical intervention for active abdominal bleeding or angiographic embolization for an abdominal arterial injury.Positive predictive value (PPV) and negative predictive value (NPV) (95% confidence interval [CI]) were calculated for all patients and in a subgroup of patients with a high risk for significant hemorrhage (base deficit ≥ 6 mEq/L).
  
  
  RESULTS
  Overall, 160 patients were included in the study. Of the 62 FF patients, 26 required AHC (PPV, 42%, 95% CI, 30-55%). Of the 98 patients without FF, none required AHC (NPV, 100%; 95% CI, 95-100%). For a moderate-to-large amount of FF, the PPV and NPV in all patients were 81% (95% CI, 60-93%) and 96% (95% CI, 91-99%), respectively.In the subgroup of 49 high-risk patients (31%), 17 of 26 FF patients required AHC (PPV, 65%; 95% CI, 44-82%), and none of the 23 patients without FF required AHC (NPV, 100%; 95% CI, 82-100%). For a moderate-to-large amount, the PPV and NPV in high-risk patients were 93% (95% CI, 64-100%) and 89% (95% CI, 72-96%), respectively.
  
  
  CONCLUSIONS
  In major pelvic fracture patients, the predictive value of FF on CT for the need for AHC is closely related to the amount present. A moderate-to-large amount of FF is highly predictive for the presence of abdominal bleeding that requires hemorrhage control.
  
  
  METHODS
  Therapeutic study, level IV; prognostic study, level III.
authors.affiliation: From the Trauma Unit, Department of Surgery (D.O.F.V., K.J.P., J.C.G.), and Department of Radiology (I.A.J.Z., C.V.D.L., O.M.V.D.), Academic Medical Center (AMC), University of Amsterdam (UvA), Amsterdam, the Netherlands.
authors.forename: Diederik O F
authors.initials: DO
authors.lastname: Verbeek
authors.forename: Ijsbrand A J
authors.initials: IA
authors.lastname: Zijlstra
authors.forename: Christaan
authors.initials: C
authors.lastname: van der Leij
authors.forename: Kornelis J
authors.initials: KJ
authors.lastname: Ponsen
authors.forename: Otto M
authors.initials: OM
authors.lastname: van Delden
authors.forename: J Carel
authors.initials: JC
authors.lastname: Goslings
mesh_terms: D000007:Abdominal Injuries / Q000150:complications / Q000000981:diagnostic imaging; D000328:Adult; D001202:Ascitic Fluid / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D050723:Fractures, Bone / Q000150:complications* / Q000000981:diagnostic imaging; D006465:Hemoperitoneum / Q000000981:diagnostic imaging* / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D006488:Hemostasis, Surgical / Q000379:methods*; D017052:Hospital Mortality; D006801:Humans; D015601:Injury Severity Score; D007813:Laparotomy / Q000379:methods; D008297:Male; D008875:Middle Aged; D010384:Pelvic Bones / Q000000981:diagnostic imaging / Q000293:injuries*; D011237:Predictive Value of Tests; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods; D014193:Trauma Centers; D016896:Treatment Outcome