title: Diagnostic performance and therapeutic consequence of thromboelastometry activated by kaolin versus a panel of specific reagents.
abstract: BACKGROUND
  Thromboelastography/metry (TEG®; Haemoscope, Niles, IL/ROTEM®; Tem International GmbH, Munich, Germany) is increasingly used to guide transfusion therapy. This study investigated the diagnostic performance and therapeutic consequence of using kaolin-activated whole blood compared with a panel of specific TEM®-reagents to distinguish: dilutional coagulopathy, thrombocytopenia, hyperfibrinolysis, and heparinization.
  
  
  METHODS
  Blood was drawn from 11 healthy volunteers. Dilutional coagulopathy was generated by 50% dilution with hydroxyethyl starch 130/0.4 whereas thrombocytopenia (mean platelet count 20 ×10⁹/l) was induced using a validated model. Hyperfibrinolysis and heparin contamination were generated by tissue plasminogen activator 2 nM and unfractionated heparin 0.1U/ml, respectively. Coagulation tests were run on ROTEM® delta.
  
  
  RESULTS
  Kaolin-activated whole blood showed no differences between dilutional coagulopathy and thrombocytopenia (mean clotting time 450 s vs. 516 s, α-angle 47.1° vs. 41.5°, maximum clot firmness 35.0 mm vs. 34.2 mm, all P values ≥0.14). Hyperfibrinolysis specifically disclosed an increased maximum lysis (median: 100%, all P values less than 0.001), and heparin induced a distinctly prolonged clotting time (2283 s, all P values less than 0.02). The coagulopathies were readily distinguishable using a panel of TEM-reagents. In particular, dilutional coagulopathy was separated from thrombocytopenia using FIBTEM (maximum clot firmness 1.9 mm vs. 11.2 mm, P < 0.001). The run time of analysis to achieve diagnostic data was shorter applying a panel of TEM-reagents. A transfusion algorithm based on kaolin suggested platelets in case of dilutional coagulopathy, whereas an algorithm applying TEM-reagents suggested fibrinogen.
  
  
  CONCLUSIONS
  Monoanalysis with kaolin was unable to distinguish coagulopathies caused by dilution from that of thrombocytopenia. Algorithms based on the use of kaolin may lead to unnecessary transfusion with platelets, whereas the application of TEM-reagents may result in goal-directed fibrinogen substitution.
authors.affiliation: Centre for Haemophilia and Thrombosis, Aarhus University Hospital, Skejby, Denmark.
authors.forename: Ole Halfdan
authors.initials: OH
authors.lastname: Larsen
authors.forename: Christian
authors.initials: C
authors.lastname: Fenger-Eriksen
authors.forename: Kirsten
authors.initials: K
authors.lastname: Christiansen
authors.forename: Jørgen
authors.initials: J
authors.lastname: Ingerslev
authors.forename: Benny
authors.initials: B
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D000465:Algorithms; D001778:Blood Coagulation Disorders / Q000175:diagnosis*; D005260:Female; D005342:Fibrinolysis; D006487:Hemostasis; D006801:Humans; D007202:Indicators and Reagents; D007616:Kaolin / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D013916:Thrombelastography / Q000379:methods*; D013921:Thrombocytopenia / Q000175:diagnosis; D013997:Time Factors
chemical_list: D007202:Indicators and Reagents; D007616:Kaolin