A comparison of kaolin-activated versus nonkaolin-activated thromboelastography in native and citrated blood.

Sheila Sherlock Hepatobiliarypancreatic and Liver Transplantation Unit, Royal Free Hospital, London, UK.
Blood Coagulation and Fibrinolysis (Impact Factor: 1.38). 09/2008; 19(6):495-501. DOI: 10.1097/MBC.0b013e3282f9adf9
Source: PubMed

ABSTRACT Thromboelastography can be performed with native or citrated blood (a surrogate to native blood in healthy controls, surgical and cirrhotic patients). Activators such as kaolin are increasingly used to reduce the time to trace generation. To compare kaolin-activated thromboelastography with nonkaolin-activated thromboelastography of native and citrated blood in patients with liver disease, patients undergoing treatment with warfarin or low-molecular weight heparin and healthy volunteers. We studied thromboelastography parameters in 21 healthy volunteers (group 1) and 50 patients, including 20 patients with liver cirrhosis with a nonbiliary aetiology (group 2), 10 patients with primary biliary cirrhosis or primary sclerosing cholangitis (group 3), 10 patients on warfarin treatment (group 4) and 10 patients with enoxaparin prophylaxis (group 5). Thromboelastography was performed using four methods: native blood (kaolin-activated and nonkaolin-activated) and citrated blood (kaolin-activated and nonkaolin-activated). For all thromboelastography parameters, correlation was poor (Spearman correlation coefficient < 0.70) between nonkaolin-activated and kaolin-activated thromboelastography, for both citrated and native blood. In healthy volunteers, in patients with liver disease and in those receiving anticoagulant treatment, there was a poor correlation between nonkaolin-activated and kaolin-activated thromboelastography. Kaolin-activated thromboelastography needs further validation before routine clinical use in these settings, and the specific methodology must be considered in comparing published studies.


Available from: Andrew K Burroughs, May 11, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Coagulation abnormalities are frequent in sepsis. Conventional coagulation assays however, have several limitations. There is a surge of interest in the use of point of care tests to diagnose hypo- and hypercoagulability in sepsis. We performed a systematic review of available literature to establish the value of rotational thromboelastography (TEG(R)) and thromboelastometry (ROTEM(R)) compared to standard coagulation tests to detect hyper- or hypocoagulability in sepsis patients. Furthermore the value of TEG(R)/ROTEM(R) to identify sepsis patients likely to benefit from therapies that interfere with the coagulation system was assessed. MEDLINE, EMBASE, and the Cochrane Library were searched from 1 January 1980 to 31 December 2012. The search was limited to adults and language was limited to English. Reference lists of retrieved papers were hand-searched for additional studies. Ongoing trials were searched on and Studies addressing TEG(R)/ROTEM(R) measurements in adult patients with sepsis admitted to the ICU were considered eligible. Of 680 screened articles, 18 studies were included, of which 2 were randomized controlled trials and 16 were observational cohort studies. In patients with sepsis, results show both hyper- and hypocoagulability, as well as TEG(R)/ROTEM(R) values which fell within reference values. Both hyper- and hypocoagulability were to some extent associated with diffuse intravascular coagulation. Compared to conventional coagulation tests, TEG(R)/ROTEM(R) can detect impaired fibrinolysis, which can possibly help to discriminate between sepsis and systemic inflammatory response syndrome (SIRS). A hypocoagulable profile is associated with increased mortality. The value of TEG(R)/ROTEM(R) to identify patients with sepsis who could possibly benefit from therapies interfering with the coagulation system could not be assessed, since studies addressing this topic were limited. TEG(R)/ROTEM(R) could be a promising tool in diagnosing alterations in coagulation in sepsis. Further research on the value of TEG(R)/ROTEM(R) in these patients is warranted. Given that coagulopathy is a dynamic process, sequential measurements are needed to understand the coagulation patterns in sepsis as can be detected by TEG(R)/ROTEM(R).
    Critical care (London, England) 02/2014; 18(1):R30. DOI:10.1186/cc13721
  • [Show abstract] [Hide abstract]
    ABSTRACT: To systematically examine the evidence relating to the performance of rotational viscoelastic testing in companion animals, to develop assay guidelines, and to identify knowledge gaps. Multiple questions were considered within 5 parent domains, specifically system comparability, sample handling, assay activation and test protocol, definitions and data reporting, and nonstandard assays. Standardized, systematic evaluation of the literature was performed. Relevant articles were categorized according to level of evidence and assessed for quality. Consensus was developed regarding conclusions for application of concepts to clinical practice. Academic and referral veterinary medical centers. Databases searched included Medline, Commonwealth Agricultural Bureaux abstracts, and Google Scholar. Worksheets were prepared evaluating 28 questions across the 5 domains and generating 84 assay guidelines. Evidence-based guidelines for the performance of thromboelastography in companion animals were generated through this process. Some of these guidelines are well supported while others will benefit from additional evidence. Many knowledge gaps were identified and future work should be directed to address these gaps and to objectively evaluate the impact of these guidelines on assay comparability within and between centers.
    01/2014; 24(1). DOI:10.1111/vec.12144
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To systematically examine the evidence on activating agents and test protocols for the thrombelastography (TEG) and rotational thrombelastometry (ROTEM) viscoelastic point-of-care instruments and to identify knowledge gaps. Ten questions were considered, the primary question addressed the use of activating agents and secondary questions addressed assay temperature, length of analysis, pipetting, sample volume, reproducibility, and quality controls. Standardized, systematic evaluation of the literature was performed. Relevant articles were categorized according to level of evidence (LOE). Consensus was developed regarding conclusions for application of concepts to clinical practice. Academic and referral veterinary medical centers. PubMed and CAB abstracts were searched. Twenty papers were initially identified concerning the primary question; 16 were in support of the questions (LOE 2 Good, LOE 3 Good, LOE 5 Good, LOE 6 Good, LOE 5 Fair, LOE 6 Fair); and 4 were neutral (LOE 3 Good, LOE 6 Good, LOE Fair, LOE 5 Fair). Additional papers were evaluated post hoc during manuscript preparation. Overall, there is a body of evidence from veterinary and human medicine that strongly suggests that TEG or ROTEM assays using citrated samples that employ an activator have significantly lower inherent variability than those that use recalcification alone. There is also strong evidence in dogs, cats, and humans that the results obtained using different activators are not directly comparable. There is no evidence to suggest that any one activating agent is superior to another for all patient populations, or drug monitoring indications. As such, use of more than one assay for complete thromboelastographic evaluation of a patient's coagulation system may be warranted. Standardization of the concentrations of activators would be beneficial.
    01/2014; DOI:10.1111/vec.12147