Method for determining the coagulation potential of a plasma sample

A method of determining the coagulation potential of a plasma sample, the method comprising the steps of:

• (a) pre-incubating the plasma sample with a reagent such that
• (i) endogenous protein C in the plasma is at least partially converted into activated protein C by the reagent, and
• (ii) adding factor Xa which is progressively inactivated by antithrombin III/heparin cofactor 2 during the preincubation;
• (b) adding an exogenous reagent which activates factor X to Xa or prothrombin to thrombin in a factor V-dependent manner to the preincubated plasma sample of step (a);
• (c) monitoring a reaction indicative of the rate of coagulation of the plasma sample;
• (d) comparing the rate of coagulation monitored in step (c) with the equivalent rate determined for an individual without impaired coagulation control, or comparing the rate of coagulation detected in step (c) with the equivalent rate determined for the plasma sample in the absence of protein C activator;
• and
• (e) determining the coagulation potential of the plasma sample from one or other of the comparisons of step (d).