Effects of storage time and temperature on thromboelastographic analysis in dogs and horses.

Abstract

BACKGROUND: The accessibility of thromboelastography (TEG) to general practitioners is limited by short sample storage times (30&#xa0;minutes) and storage temperatures (20-23&#xb0;C). OBJECTIVES: We aimed to evaluate the stability of canine and equine citrated blood samples when stored for extended periods of time, both at room temperature (RT) (20-23&#xb0;C) and refrigerator temperature (FT) (2-7.5&#xb0;C). METHODS: Citrated whole blood samples from healthy dogs and horses (n&#xa0;=&#xa0;10 for each) were stored for 30&#xa0;minutes (baseline) at RT before TEG analysis. Baseline values for TEG variables R, K, &#x3b1;, MA, LY30, and LY60 were compared with those from samples stored for 2, 8, and 22.5&#xa0;h, at RT and FT. Results were compared using an ANOVA (P&#xa0;<&#xa0;.05). Total allowable analytical error (TE) based on biological variation data was used to evaluate stability. RESULTS: In dogs, statistically significant differences included shorter R, longer K, decreased MA, and increased LY60 at various time points and storage temperatures from 2&#xa0;h onward. Only samples stored for 2&#xa0;h at FT showed acceptable stability compared with TE. In horses, statistically significant differences included shorter R and K, and decreased &#x3b1;, LY30, and LY60 at various time points and storage temperatures from 2&#xa0;h onward. Samples were not stable at any time compared with TE, regardless of the temperature. CONCLUSIONS: In this study, canine samples could be stored for up to 2&#xa0;h at FT without affecting TEG results; equine samples should be stored for 30&#xa0;minutes at RT.