Problems Raised By The Measurement Of Coagulation Factors On Chromogen Substrates By Automatic Methods

Abstract

The use of chromogen substrates has permitted a new approach of the factors responsible for the regulation and equilibrium of hemostasis.Automation has allowed to have access to the problems raised by enzymatic reactions in non-purified medium. The specificity and sensibility of substrates, the specificity of activators, the role of inhibitors and physiologic substrates in different technical conditions (pH, ionic forces, temperature, dilution) modifying the maximal velocity, have been studied for a standardizing approach of enzymatic kinetics in hemostasis. Measurements of antithrombin III and fast α2 antiplasmin, factor X, prekallikrein and plasminogen and heparinemies have been analyzed by an automatic apparatus (Kern O Mat 2-Coultronics) with different chromogen substrates (Kabi-Stago).Optimum technical conditions, units in which results are expressed, interpretation of normal and pathological values are systematically studied.