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Objective To systematically examine the evidence on nontraditional uses of viscoelastic coagulation monitoring in veterinary species. Design Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. Setting Academic and referral veterinary medical centers. Results Databases searched included Medline, CAB abstracts, and Google Scholar. Conclusions Nontraditional assays identified included thrombelastography (TEG)-PlateletMapping (PM), functional fibrinogen assessment, and rapid-TEG (r-TEG). Direct veterinary evidence was found for only the ADP-activated PM, which appears to generate valid data in dogs but not cats or horses. Arachidonic acid activated PM shows high variability and requires further assessment and validation in veterinary species. Functional fibrinogen assays may be performed in veterinary species but may require modification due to species differences in response to abciximab. While tissue factor (TF)-activated TEG has been well described in the veterinary literature, the specific r-TEG assay has not been assessed, but presumably would be effective for generating TEG tracings and values for maximum amplitude and angle in shorter periods of time than some traditional assays. [ABSTRACT FROM AUTHOR]

Objective To systematically examine the evidence on system comparability between the thromboelastography and the rotational thromboelastometry viscoelastic point-of-care instruments and to identify knowledge gaps. Design Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice. Setting Academic and referral veterinary medical centers. Results Medline via PubMed, CAB abstracts, and Google Scholar were searched. A total of 8 relevant articles were chosen, none were in support of the question, 1 was neutral to the question (level of evidence [LOE] 6, Poor), and 7 were in opposition to the question (LOE 3 Good; LOE 6 Good; LOE 6 Fair; LOE 6 Poor). Conclusions Results from the 2 analyzers are not directly comparable and extrapolation of the results from one machine to the other should be avoided. Standardization of the preanalytical variables (eg, blood collection, holding time, and temperature during holding) is strongly recommended. It is recommended that each site create their own 'site specific' reference values for each machine and that test samples be compared only to the standardized reference values established at that center. Start-up and consumable costs vary between countries and local comparisons should be performed. Decisions should be made based on the expected use of the machine and if multiple operators will be using it. [ABSTRACT FROM AUTHOR]

Objective 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. Design 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. Setting Academic and referral veterinary medical centers. Results 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. Conclusions 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. [ABSTRACT FROM AUTHOR]