Here is a note about the ecarin time from Twyla Bader:
George, how commonly is the ecarin time being used to monitor hirudin during surgery? Also is there any device that performs this superior compared to others?
Thank you, Twyla Bader
Hello, Twyla, thanks for the question. The ecarin time uses venom from Echis carinatus as the triggering reagent in a clot-based assay that otherwise proceeds like a prothrombin time. The ecarin time may be used to monitor direct thrombin inhibitors (DTIs) argatroban, lepirudin (hirudin) and bivalirudin, as it provides a linear response within the therapeutic range for each and function well on any coagulometer. Although the ecarin time is used in Europe and is available from specialty coagulation testing reference laboratories, I know of no local institution that offers it as a routine DTI monitor, as DTIs may also be monitored using the partial thromboplastin time (PTT), or in the case of high doses during cardiac surgery, the activated coagulation time (ACT). The ecarin time may be useful in those cases where the PTT is compromised, such as when a lupus anticoagulant is present, but there is little demand for making it regularly available. Geo
There is a better and even more specific method, the ecarin
There is a better and even more specific method, the ecarin chromogenic assay (ECA, Stago, currently for research use only). ECA is not dependent on patient coagulation factors and not subject to interference by lupus anticoagulants. It provides the highest level of specificity. PTT is not specific and may show a plateau effect at higher concentrations. The ACT is even less specific.