Changes in Thrombelastograph??? Variables Associated with Aging

In Brief Aging is associated with hypercoagulability. To assess thrombelastography (TEG®) variables associated with aging, 132 adult patients of various ages undergoing orthopedic surgery for fracture repair had venous blood samples withdrawn for testing of recalcified TEG® before the induction of anesthesia. Age was weakly correlated with all TEG® variables: r time (R) (r = −0.45, P < 0.001; R = 19.5 − 0.09 × age), k time (K) (r = −0.49, P < 0.001; K = 6.5 − 0.04 × age), maximum amplitude (MA) (r = 0.25, P <0.01; MA =53.3 + 0.07 × age), and α (r = 0.52, P < 0.001; α = 52.8 + 0.2 × age). The correlation was stronger for men than for women. Only R was significantly correlated with age when the women were separately analyzed. Part of the correlation may be attributable to a concurrent decrease in hemoglobin with aging, but age remained an independent predictor of R, K, and α on forward stepwise linear multiple regression analysis. Aging was weakly associated with changes in TEG® variables, which should be allowed for when interpreting TEG® measurements in the elderly. IMPLICATIONS: Aging is associated with changes in thrombelastography (TEG®) variables. They change by approximately 20%–40% in the hypercoag-ulable direction in an 80-yr-old compared with a 20-yr-old. These difference may be important when TEG® interpretation involves patients of different ages, such as in clinical trials or when TEG®-based transfusion algorithms are applied.