Evaluation of a modified thrombelastography assay initiated with recombinant human tissue factor in clinically healthy horses.

The research explores the use of Thrombelastography (TEG), instigated with recombinant human tissue factor (TF), to study blood clotting behavior in healthy horses. It investigates how the lapse between blood sampling and analysis impacts the study results and aims to establish a preliminary reference interval for a modified TEG assay.

Key Objectives and Methods

• The main goal of the study is to identify whether the time elapsed between the sampling and analysis of equine blood samples impacts the test results of TEG, where coagulation is initiated using recombinant human TF.
• The researchers collected citrated blood samples from 20 clinically healthy adult horses for the experiment. They stored thirteen of these samples at room temperature for 30, 60, and 120 minutes before conducting the TEG analysis.
• The blood was made to coagulate by adding a specific ratio of CaCl(2) and diluted recombinant TF to the horse blood.
• They examined and compared several factors related to coagulation, such as Reaction (R) and clotting (K) times, angle (alpha), and maximum amplitude (MA), between the time points.
• They also set a preliminary reference interval or parameters for horse blood sample using all 20 horse blood samples but only after 30 minutes of sample storage.

Research Findings

• The results confirmed that the storage time significantly influenced the R, K, and alpha, but not the MA.
• They established reference intervals for all the factors examined in the study.
• The study discovered that lysis at 30 minutes post-MA (LY30) was less than 2.75% and lysis at 60 minutes post-MA (LY60) was between 1.55-9.5%.

Conclusions

• TEG can be successfully performed on equine citrated blood samples using recombinant human TF to activate clot formation, opening additional avenues for equine medical studies.
• However, the TEG parameters were significantly affected by storage time, implying that coagulation in citrated blood was not completely inhibited during storage.