Thromboelastography (TEG) is considered a rapid, reproducible test of hemostatic function in whole blood. This analytical method has been previously evaluated in humans, dogs and select species to identify and quantify alterations of both hyper- and hypocoagulative disease states. TEG may have similar diagnostic potential in New World Camelids with hemostatic disorders, augmenting traditional coagulation parameters. The objective of this study was to establish a clinically applicable reference interval for reaction time (R), clotting time (K), angle (a), and maximum amplitude (MA) of TEG on citrated whole blood from 21 clinically healthy alpacas.
Ten milliliters citrated whole blood from 15 clinically healthy adult alpacas (1-7yrs) and 6 neonatal crias (1-14 days) was collected by direct venipuncture. TEG analysis (using recombinant human tissue factor) was performed in duplicate at room temperature, 30 minutes after collection. Prothrombin time (PT) and partial thromboplastin time (PTT) were obtained concurrently.
Mean values of TEG parameters (+/- SD) for adult alpacas and neonatal crias were respectively, R= 7.7 (2.9), 5.6 (2.2); K= 3.53 (1.43), 2.55 (1.18); α= 48.1° (11.2), 56.2° (10.4); MA= 55.5 (8.35) and 59 (3.21) mm. Mean PT and PTT were 8.6s (0.6) and 18.9s (1.9) in adults vs. 9.4s (0.6) and 18.1s (1.96) in neonates. A significant difference was not observed between age groups.
Compared to reported TEG results from dogs and horses, alpacas show relatively shorter clotting times (K). Thus, species-specific normal values are necessary for interpretation of TEG parameters.