Article

Diagnostic Performance and Therapeutic Consequence of Thromboelastometry Activated by Kaolin versus a Panel of Specific Reagents

Centre for Haemophilia and Thrombosis, Aarhus University Hospital, Skejby, Denmark.
Anesthesiology (Impact Factor: 6.17). 06/2011; 115(2):294-302. DOI: 10.1097/ALN.0b013e318220755c
Source: PubMed

ABSTRACT 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.
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.
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.
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.

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    • "On the other hand, algorithms based on a panel of ROTEM ® reagents may avoid platelet transfusion when goal-directed fibrinogen substitution is more appropriate (Figs. 15.2 and 15.3a–h) (Larsen et al. 2011; Görlinger et al. 2010, 2011a, b). This is of special importance in liver transplantation since platelet transfusion is associated with a significant reduction in 1-year survival (74 % vs. 92 %; P < 0.001) in this clinical setting (Pereboom et al. 2009a, b). "
    Perioperative Hemostasis: Coagulation for Anesthesiologists, Edited by Carlo E. Marcucci, Patrick Schoettker, 01/2015: chapter Perioperative Hemostasis in Hepatic Surgery: pages 267-283; Springer Verlag, Berlin, Heidelberg.
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    • "Another criticism to TEG®-based algorithms is its mono-analysis with a single activator (Kaolin) compared to algorithms based on multiple assays (i.e. ROTEM®) with improved diagnostic efficacy [56]. Harr [33] recently pointed out that TEG inability to differentiate between fibrinogen and platelet contribution to clot firmness resulted in two TEG®-based algorithms proposing different interventions to treat the same problem (low clot strength). "
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