Age- and gender-related reference ranges for thromboelastography from a healthy Indian population

Thromboelastography (TEG) is a whole blood clotting assay largely used in major surgeries and trauma to monitor patients' in vivo hemostatic status. Standardization of kaolin-activated citrated whole blood thromboelastography is not done in the Indian population. This study primarily aims to derive reference ranges of kaolin-activated TEG for healthy volunteers in the Indian population. Secondarily, it aims to study the age- and gender-related hemostatic changes in the study population.

A total of 120 healthy volunteers were enrolled (55 adult males, 32 adult females, and 33 children). The volunteers were interviewed for any bleeding history or drug intake which affects coagulation. Kaolin-activated TEG was performed on citrated whole blood, and parameters including R-time, K-time, angle, MA, LY30, and CI were analyzed.

Derived reference range for total volunteers irrespective of age and sex were as follows: R-time: 3.8-10.6, K-time: 1.2-3.1, angle: 44.9-72.0, MA: 41.2-64.5, LY30: 0-9.9, and CI: -3.7 to 3.4. Statistically significant difference was observed in different age and sex groups for R-time, K-time, and angle. About 40% of the volunteers had at least one abnormal parameter according to the manufacturer's reference range which decreased to 12.5% when the derived reference ranges were considered.

Gender- and age-related variances were observed in reference ranges of our population and which was also differed from the other ethnic population. Many of our healthy volunteers were categorized as coagulopathic when manufacturer's reference range was considered. So, it is important to derive the reference range of the target population before using the TEG into clinical practice.