title: Utility of a point-of-care device for rapid determination of prothrombin time in trauma patients: a preliminary study.
abstract: BACKGROUND
  Rapid and accurate determination of prothrombin time in trauma patients may help to faster control of bleeding induced coagulopathy. The goal of this prospective observational study was to investigate the accuracy of bedside measurements of prothrombin time by the mean of a point-of-care device (INRatio) in trauma patients.
  
  
  METHODS
  Fifty blood samples were drawn at admission and during the acute care phase for standard coagulation assays (prothrombin time, International Normalized Ratio [INR], and fibrinogen) and INRatio testing (INR(A)) from 48 trauma patients.
  
  
  RESULTS
  Standard coagulation assays were available after a mean of 66 minutes. Median Injury Severity Score was 18, and 16 patients (33%) had a coagulopathy. Significant correlation was found between INR and INR(A) (r: 0.93, 95% confidence interval: 0.87-0.96). The mean difference (bias) for INR was 0.00, and standard deviation (precision) of the difference was 0.78. However, in cases where there was decreased hemoglobin (<10 gr · L(-1)) and fibrinogen (<1.5 gr · L(-1)), bias and precision were increased. To predict the need for fresh frozen plasma transfusion (INR > 1.5), INR(A) cutoff value of 1.3 resulted in a sensitivity of 92% and a specificity of 79%. The area under the receiver operating characteristic curve was 0.946 (95% confidence interval: 0,845-0,982).
  
  
  CONCLUSIONS
  INRatio may be a useful device in the management of trauma patients with ongoing or suspected coagulopathy that may help to save at least 60 minutes in the process of obtaining a prothrombin time result. It may allow earlier detection of coagulopathy and, together with vital sign and hemoglobin, may help to guide fresh frozen plasma transfusion.
authors.affiliation: Department of Anesthesia and Critical Care Medicine, Lyon-Sud Hospital, Hospices Civils de Lyon and University Lyon 1, Lyon, France. js-david@univ-lyon1.fr
authors.forename: Jean-Stéphane
authors.initials: JS
authors.lastname: David
authors.forename: Albrice
authors.initials: A
authors.lastname: Levrat
authors.forename: Kenji
authors.initials: K
authors.lastname: Inaba
authors.forename: Caroline
authors.initials: C
authors.lastname: Macabeo
authors.forename: Lucia
authors.initials: L
authors.lastname: Rugeri
authors.forename: Oriane
authors.initials: O
authors.lastname: Fontaine
authors.forename: Aurélie
authors.initials: A
authors.lastname: Cheron
authors.forename: Vincent
authors.initials: V
authors.lastname: Piriou
mesh_terms: D000328:Adult; D001778:Blood Coagulation Disorders / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D019095:Point-of-Care Systems / Q000706:statistics & numerical data*; D011446:Prospective Studies; D011517:Prothrombin Time / Q000295:instrumentation* / Q000706:statistics & numerical data; D012372:ROC Curve; D015203:Reproducibility of Results; D014949:Wounds, Nonpenetrating / Q000097:blood* / Q000150:complications / Q000175:diagnosis