Effects of Fibrinogen Levels and Platelet Counts on Viscoelastic Testing in Cirrhotic Patients

Introduction: Cirrhotic patients have been considered for decades to have a pro-haemorrhagic pattern and were treated as such based on the results from standard coagulation tests. The aim of our study was to determine the effects of platelet count and fibrinogen levels on rotational thromboelastometry (ROTEM) parameters. Methods: We prospectively included 176 patients with End-Stage Liver Disease (ESLD) admitted to our Intensive Care Unit prior to liver transplantation. Collected data consisted of severity scores, liver, renal and standard coagulation tests, fibrinogen levels, platelet counts and ROTEM parameters. Four ROTEM assays were performed (ExTEM, InTEM, ApTEM and FibTEM) and the following parameters included: CT - clotting time, CFT - clot formation time, MCF - maximum clot firmness, ML - maximum lysis, alpha angle, TPI - thrombin potential index, MaxV - maximum velocity of clot formation (MaxV), MaxVt - time to MaxV, MCE - maximum clot elasticity and AUC - area under the curve. Results: Statistical analysis demonstrated a linear correlation between platelet counts and ExTEM TPI (R2 linear =0.494), ExTEM MaxV (R2 linear =0.253), ExTEM MCE (R2 linear = 0.351) and ExTEM MCF (R2 cubic = 0.498). Fibrinogen levels correlated linearly with ExTEM MCF (R2 linear = 0.426), ExTEM TPI (R2 linear = 0.544), ExTEM MaxV (R2 linear = 0.332), ExTEM MCE (R2 linear = 0.395) and non-linearly with ExTEM CFT (R2 cubic = 0.475). Conclusion: Fibrinogen levels and platelet counts had an important effect on both standard and derived ROTEM parameters. Further analysis is required in order to determine clinically oriented cut-off values below which severe coagulopathy would develop.