Reference Values for Kaolin-Activated Thromboelastography in Healthy Children

Department of Clinical Hematology, Royal Children's Hospital, Melbourne, Australia.
Anesthesia and analgesia (Impact Factor: 3.47). 01/2008; 105(6):1610-3, table of contents. DOI: 10.1213/
Source: PubMed


The hemostatic system of children changes with age and differs significantly from the hemostatic system of adults. Age-specific reference values are therefore required for most hemostatic variables. Thromboelastography (TEG) is a point-of-care coagulation test that may provide superior evaluation and management of coagulopathies after cardiac surgery, when large-dose unfractionated heparin is administered for cardiopulmonary bypass. In this study, we established reference values for kaolin-activated TEG in healthy children, to facilitate accurate interpretation of pediatric TEG results.
Kaolin-activated TEG was performed on 100 healthy children undergoing elective day surgery and 25 healthy adult volunteers. The following TEG variables were recorded: reaction time, coagulation time, alpha angle, maximum amplitude, percentage lysis 30 min after maximum amplitude was reached, and the coagulation index. Differences between age-groups were evaluated using analysis of variance.
Age-specific reference values for kaolin-activated TEG in healthy children between 1 mo and 16 yr of age are presented. No significant differences between children and adults were observed.
TEG results, from a particular clinical setting, must be compared to age-specific, as well as analyzer- and activator-specific, reference values to allow for correct interpretation of the results. Reference values provided here will be of use in acute clinical situations where a practical monitor of hemostasis is required.

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    • "There are multiple reagents (kaolin, celite, tissue factor) that could have been used to accelerate the clotting process or study a specific component of the clotting cascade. The only reference ranges that have been established for pediatric patients are for whole blood and kaolin-and celiteactivated specimens [18] [28] [29]. This study utilized recalcified citrated whole blood samples, which do not yet have an established reference range in pediatric patients. "
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