title: Rapid thrombelastography delivers real-time results that predict transfusion within 1 hour of admission.
abstract: BACKGROUND
  Recognition of trauma-induced coagulopathy by conventional coagulation testing (CCT) is limited by their slow results, incomplete characterization, and their poor predictive nature. Rapid thrombelastography (r-TEG) delivers a more comprehensive assessment of the coagulation system but has not been prospectively validated in trauma patients. The purpose of this pilot study was to evaluate the timeliness of r-TEG results, their correlation with CCTs, and the ability of r-TEG to predict early blood transfusion.
  
  
  METHODS
  Over a 5-month period, 583 consecutive major trauma activations were prospectively entered into a database, of which 272 met entry criteria. r-TEG and CCTs (prothrombin time, international normalized ratio, partial thromboplastin time, and platelet count) were obtained on all patients. Graphical results for r-TEG were displayed "real time" in the trauma bay. Spearman's correlation and regression models were used to compare r-TEG and CCTs.
  
  
  RESULTS
  Early r-TEG values (activated clotting time [ACT], k-time, and r-value) were available within 5 minutes, late r-TEG values (maximal amplitude and α-angle) within 15 minutes, and CCTs within 48 minutes (p < 0.001). ACT, r-value, and k-time showed strong correlation with prothrombin time, international normalized ratio, and partial thromboplastin time (all r >0.70; p < 0.001), whereas maximal amplitude (r = -0.49) and α-angle (r = 0.40) correlated with platelet count (both p < 0.001). Linear regression demonstrated ACT predicted red blood cells (coef. 0.05; 95% confidence interval [CI], 0.04-0.06; p < 0.001), plasma (coef. 0.03; 95% CI, 0.02-0.04; p < 0.001), and platelet (coef. 0.06; 95% CI, 0.04-0.07; p < 0.001) transfusions within the first 2 hours of arrival. Controlling for all demographics and Emergency Department vitals, ACT >128 predicted massive transfusion (≥10 U) in the first 6 hours (odds ratio, 5.15; 95% CI, 1.36-19.49; p = 0.01). In addition, ACT <105 predicted patients who did not receive any transfusions in the first 24 hours (odds ratio, 2.80; CI, 1.02-7.07; p = 0.04).
  
  
  CONCLUSIONS
  Graphical r-TEG results are available within minutes, correlate with conventional coagulation test that are not as rapidly available, and are predictive of early transfusions of packed red blood cells, plasma, and platelets.
authors.affiliation: Department of Surgery, The University of Texas Health Science Center, Houston, Texas 77030, USA. bryan.a.cotton@uth.tmc.edu
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Cotton
authors.forename: Gabriel
authors.initials: G
authors.lastname: Faz
authors.forename: Quinton M
authors.initials: QM
authors.lastname: Hatch
authors.forename: Zayde A
authors.initials: ZA
authors.lastname: Radwan
authors.forename: Jeanette
authors.initials: J
authors.lastname: Podbielski
authors.forename: Charles
authors.initials: C
authors.lastname: Wade
authors.forename: Rosemary A
authors.initials: RA
authors.lastname: Kozar
authors.forename: John B
authors.initials: JB
authors.lastname: Holcomb
mesh_terms: D000328:Adult; D001778:Blood Coagulation Disorders / Q000175:diagnosis*; D016913:Blood Component Transfusion; D001803:Blood Transfusion / Q000706:statistics & numerical data*; D057286:Electronic Health Records; D005260:Female; D006760:Hospitalization; D006801:Humans; D015601:Injury Severity Score; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010865:Pilot Projects; D013048:Specimen Handling; D013916:Thrombelastography / Q000379:methods*; D013997:Time Factors; D014947:Wounds and Injuries / Q000150:complications; D055815:Young Adult