Rheometry for Blood Coagulation Studies

This review considers some of the various rheometrical approaches that have been adopted to study blood coagulation, with special reference to the rheological assessment of clotting time and studies of the evolution of viscoelasticity during the course of fibrin polymerization and cross-linking. A common feature of many of these studies is that they attempt to detect a liquid-to-solid transition during coagulation and the significance of the Gel Point in blood coagulation studies is discussed. Coagulation studies based on various forms of shear viscosity measurements and complex shear modulus measurements are considered, the latter being based principally on instruments such as the various controlled stress and controlled strain rheometers. Also considered is the long established technique of thromboelastography, while several emerging techniques are described. The latter include damped oscillation rheometry, various forms of wave propagation measurements and other, less widely used techniques such as free oscillation rheometry, quartz crystal microbalance measurements and surface plasmon resonance.