Fibrinogen assays

Abstract

Fibrinogen plays a central role in haemostasis. Several studies have identified fibrinogen as the most vulnerable coagulation protein, reaching critically low levels earlier than any other coagulation factor in the course of major blood loss. Therefore, a rapid and repeated measurement of fibrinogen concentration is strongly recommended in trauma patients with substantial blood loss. Recent guidelines recommend maintaining plasma fibrinogen concentration above 1.5-2 g/L in bleeding patients. About 60 different methods to measure fibrinogen have been described in order to determine plasma fibrinogen concentration. The most common technique established in many laboratories is the method developed by Clauss. Several factors, including type of device and reagent, have been shown to affect the results of the fibrinogen measured by the Clauss method. An important shortcoming of all standard coagulation tests in plasma, including fibrinogen measurements, is the long turnaround time until results are available. A recently proposed alternative approach to provide fibrinogen values faster is whole blood fibrinogen measurements. Moreover, specific viscoelastic assays, such as the ROTEM FIBTEM, ClotPro FIB-test, TEG functional fibrinogen and Quantra fibrinogen contribution, allow a rapid assessment of fibrin polymerisation in whole blood under platelet inhibition and are frequently used to guide fibrinogen supplementation in bleeding trauma patients.