Clinical applicability of rapid thrombelastography and functional fibrinogen thrombelastography to adult liver transplantation

Abstract

Unlike kaolin thrombelastography (k-TEG), the clinical utility of rapid thrombelastography (r-TEG) and functional fibrinogen thrombelastography (FF-TEG) has not been tested in liver transplantation (LT). These thrombelastography techniques were simultaneously performed at the time of the skin incision (the baseline) and 30 minutes after graft reperfusion (III 1 30) for 27 consecutive adult LT patients. k-TEG and r-TEG parameters [alpha angle (a) and maximum amplitude of the clot (MA)] were compared in addition to the assay time. Estimated FF-TEG fibrinogen levels were compared with plasma fibrinogen measurements. At the baseline, the values of Spearman's correlation coefficient (r) between k-TEG and r-TEG were moderate for a (r 5 0.40, P 5 0.06) and strong for MA (r 5 0.90, P < 0.01). At III 1 30, r was 0.46 (P < 0.05) for a and 0.80 (P < 0.01) for MA. The average time required to measure MA via r-TEG was decreased in comparison with k-TEG [from 29.7 to 21.6 minutes at the baseline (a 22% reduction) and from 29.6 to 22.9 minutes at III 1 30 (a 23% reduction)]. FF-TEG correlated strongly with the plasma fibrinogen level at the baseline (r 5 0.90, P < 0.01); however, FF-TEG overestimated the fibrinogen level at III 1 30 (r 5 0.58, P 5 0.01). In conclusion, in adult LT, r-TEG correlates with k-TEG strongly for MA but only moderately for a. FF-TEG estimates the plasma fibrinogen level well at the baseline; however, it must be interpreted with caution because of its overestimation after graft reperfusion when the plasma fibrinogen level often decreases to less than 100 mg/dL.

Impact of Preemptive Fibrinogen Concentrate on Transfusion Requirements in Liver Transplantation: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

“…Furthermore, the evaluation of plasma fibrinogen itself is problematic. Functional fibrinogen may be calculated automatically on the basis of clot firmness by eliminating the platelet contribution in viscoelastic tests, but in bleeding surgical patients (17) and in LT after graft reperfusion (18), the calculated value overestimates the value measured by the conventional Clauss method (17,18). The intensity of platelet inhibition also influences the accurate assessment of clot firmness, on which calculations will be based (19).…”

Correlation between plasma fibrinogen and FIBTEM thromboelastometry during liver transplantation: a comprehensive assessment

“…Also, gross coagulation alterations can occur; a flat line has been described in up to 27% of the cases and was attributed to hyperfibrinolysis and/or tissue factor and anticoagulants released by the new liver . Additionally, the number of technical errors (tests that failed to coagulate or resulted in artificial errors in the final result) increased after reperfusion . All these factors can justify the lack of correlation between FIBTEM MCF and plasma fibrinogen at this time.…”

Perioperative Thromboelastometry for Adult Living Donor Liver Transplant Recipients with a Tendency to Hypercoagulability: A Prospective Observational Cohort Study

“…Inconsistent correlation between FIBTEM MCF and plasma fibrinogen concentration in patients undergoing liver transplantation can be explained by the presence of dysfibrinogenemia in this patient population which is associated with fibrin polymerization disorders [34,35,36,37,38,39,40]. Furthermore, it has been demonstrated in several publications and in a meta-analysis by Segal et al [41] that prolonged conventional coagulation tests are not associated with bleeding in cirrhosis.…”