Summary
Factor XIII (F XIII) is an essential parameter for final clot stability. The purpose
of this study was to determine the impact of the addition of factor (F)XIII on clot
stability as assessed by Rotation Thromboelastometry (ROTEM®). In 90 intensive care
patients ROTEM® measurements were performed after in vitro addition of F XIII 0.32 IU, 0.63 IU, 1.25 IU and compared to diluent controls (DC;
aqua injectabile) resulting in approximate F XIII concentrations of 150, 300 and 600%.
Baseline measurements without any additions were also performed. The following ROTEM®
parameters were measured in FIBTEM and EXTEM tests: clotting time (CT), clot formation
time (CFT), maximum clot firmness (MCF), maximum lysis (ML), maximum clot elasticity
(MCE) and α-angle (αA). Additionally, laboratory values for FXIII, fibrinogen (FBG),
platelets and haematocrit were contemporaneously determined. In the perioperative
patient population mean FBG concentration was elevated at 5.2 g/l and mean FXIII concentration
was low at 62%. The addition of FXIII led to a FBG concentration-dependent increase
in MCF both in FIBTEM and EXTEM. Mean increases in MCF (FXIII vs. DC) of approximately
7 mm and 6 mm were observed in FIBTEM and EXTEM, respectively. F XIII addition also
led to decreased CFT, increased αA, and reduced ML in FIBTEM and EXTEM. In vitro supplementation of FXIII to supraphysiologic levels increases maximum clot firmness,
accelerates clot formation and increases clot stability in EXTEM and FIBTEM as assayed
by ROTEM® in perioperative patients with high fibrinogen and low FXIII levels.
Keywords
Thromboelastometry - blood coagulation - haemostasis - thromboelastography - factor
XIII