Background: The aim of this in-vitro pilot study was to assess the usefulness of the thrombelastograph ROTEM® for determining the anticoagulant activity of lepirudin.
Methods: The ROTEM® parameters, clotting-time, clot formation time and maximum clot firmness were measured in the presence of increasing concentrations of lepirudin (10-4 μg/ml - 10 μg/ml). Citrated blood was obtained from 16 healthy male subjects.
Results: Clotting-time increased from 79.1 ± 53.4 s at baseline to 194.1 ± 151.9 s at a drug concentration of 1μg/ml as measured with EXTEM (p < 0.0001). Borderline significance was found for the difference between maximum clot firmness at baseline (60.2 ± 4.3 mm) and after drug application (55.5 ± 6.5 mm).
Conclusions: This pilot investigation shows that the ROTEM® device may be suitable for monitoring lepirudin at low concentrations but the results should be confirmed in a larger study and the ROTEM® device validated against standard methods.