Thromboelastography (TEG®) compared to conventional coagulation tests in surgical patients – a laboratory evaluation. (April 2013)

• Record Type: Journal Article
• Authors: Ågren, Anna; Wikman, Agneta Taune; Holmström, Margareta; Östlund, Anders; Edgren, Gustaf
• Is Part Of: Scandinavian journal of clinical & laboratory investigation. Volume 73:Number 3(2013)
• Page Start: 214
• Page End: 220
• Publication Date: 2013-04
• Subjects: Clinical biochemistry -- Periodicals; Physiology, Pathological -- Periodicals; Physiology, Experimental -- Periodicals; Medicine -- Research -- Periodicals; Clinical medicine -- Periodicals; 616.0072
• DOI: 10.3109/00365513.2013.765960
• Languages: English
• ISSNs: 0036-5513

Abstract

<abstract> <title>Abstract</title> <p> <bold> <italic>Background</italic>.</bold> Several methods exist for evaluation of hypocoagulation in patients with perioperative bleeding, e.g. thromboelastography (TEG<sup>®</sup>) and conventional methods (platelet count, aPTT, INR and fibrinogen). Considering the vast experience of conventional methods it is important to investigate how well the methods correspond. <bold><italic>Methods</italic>.</bold> Sixty surgical patients were included prospectively and blood samples were taken perioperatively. TEG<sup>®</sup> and conventional parameters were analyzed simultaneously. An assessment of coagulopathy, based on a synthesis of the conventional methods, was done by two experienced coagulation specialists, blinded from the results of TEG<sup>®</sup> and from the results of each other. Hypocoagulation, defined by TEG<sup>®</sup> parameters; reaction time (R-time), angle, maximal amplitude (MA) and fibrinolysis, was evaluated according to a commonly used algorithm. <bold><italic>Results</italic>.</bold> To detect a platelet count below 150 × 10<sup>9</sup> L<sup>−1</sup>, the sensitivity of TEG was 17% (95% CI, 7–36%) with angle and 25% (95% CI, 11–45%) with MA. The sensitivity to detect fibrinogen below 2 g/L was 11% (95% CI, 3–29%) with angle and 21% with MA (95% CI, 8–43%). To detect aPTT more than 40 s and INR more than 1.2 with R-time, the sensitivity was 19% (95% CI, 8–37%) and 0% (95% CI, 0–69%) respectively. The agreement of the evaluator's assessments of hypocoagulation was 100%, but the agreement with the overall TEG<sup>®</sup> analysis was poor with a sensitivity of 33% and a specificity of 95%. <bold><italic>Conclusion</italic>.</bold> The agreement between conventional laboratory tests and TEG is poor, but it remains uncertain which type of coagulation tests that best reflects the actual bleeding risk.</p> </abstract>