title: A simple assessment of haemothoraces thickness predicts abundant transfusion: a series of 525 blunt trauma patients.
abstract: BACKGROUND
  The goal of this study was to evaluate the performance of haemothorax quantification to predict an abundant transfusion in blunt thoracic trauma patients.
  
  
  METHODS
  This study included all severe trauma patients admitted into our trauma centre from January 2005 to January 2010, who presented a blunt thoracic trauma (thoracic AIS ≥1) and had a CT scan within the first hour following admission. For each haemothorax, thickness of dominant side and the cumulated thicknesses of both sides (Dominant-t, Cumulated-t), as well as lengths (Dominant-l, Cumulated-l) and the calculated volumes (Dominant-v, Cumulated-v provided by a previously validated formula) were retrospectively measured by CT scan. A multiple logistic regression was performed to define the independent risk factors for an abundant transfusion (≥5 packed red blood cells in the first 24h). Finally, ROC curves have been drawn on an isolated thoracic trauma subgroup to predict abundant transfusion. The more specific cut-offs were extracted from this analysis.
  
  
  RESULTS
  From the 525 blunt thoracic trauma patients (75% males, mean age 38.2 (SD18.7) years, mean ISS 22.5 (SD16.4)), 31% received an abundant transfusion. In multivariable analysis, Cumulated-t was significantly associated with an abundant transfusion (OR 1.3 [95% CI 1.1-1.4], P=0.002). In isolated thoracic trauma subgroup (n=251), the global abilities of different CT measurements to predict abundant transfusion were significantly comparable (AUCs 0.69-0.70). The more specific cut-offs were established at 28mm for Cumulated-t (specificity 92%, positive predictive value 47%) and at 24mm for Dominant-t (specificity 92%; positive predictive value 43%).
  
  
  CONCLUSIONS
  The haemothorax quantification upon admission may help to predict transfusion needs. Cumulated-t was found independent risk factor for abundant transfusion in a large population of severe trauma patients. Beyond a Cumulated-t of 28mm or a Dominant-t of 24mm, abundant transfusion will be very frequently necessary.
  
  
  METHODS
  Retrospective review, level III.
authors.affiliation: Trauma Intensive Care Unit, Lapeyronie University Hospital, Montpellier, France. Electronic address: lucile.gignon@gmail.com.
authors.forename: Lucile
authors.initials: L
authors.lastname: Gignon
authors.affiliation: Trauma Intensive Care Unit, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Charbit
authors.affiliation: Trauma Intensive Care Unit, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Maury
authors.affiliation: Department of Hemovigilance and Transfusion, Lapeyronie University Hospital, Montpellier, Cedex 5, F-34295, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Latry
authors.affiliation: Department of Radiology, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Patrice
authors.initials: P
authors.lastname: Taourel
authors.affiliation: Department of Radiology, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Millet
authors.affiliation: Trauma Intensive Care Unit, Lapeyronie University Hospital, Montpellier, France; Institut National de la Santé et de la Recherche Médicale, Equipe soutenue par la Région et l'Inserm U1046, Montpellier, Cedex 5, F-34295, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Capdevila
mesh_terms: D000328:Adult; D001803:Blood Transfusion / Q000706:statistics & numerical data; D005260:Female; D006491:Hemothorax / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D011379:Prognosis; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D013898:Thoracic Injuries / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D014193:Trauma Centers; D014949:Wounds, Nonpenetrating / Q000150:complications / Q000000981:diagnostic imaging* / Q000628:therapy
keywords: Blunt thoracic trauma; Transfusion prediction; Traumatic haemothorax