title: Performance of various laboratory assays in the measurement of dabigatran in patients receiving therapeutic doses: a prospective study based on peak and trough plasma levels.
abstract: OBJECTIVE
  To study dabigatran etexilate, a new oral anticoagulant that functions as a direct thrombin inhibitor.
  
  
  METHODS
  This study evaluates four methods, one of which is performed in three different laboratories, and compares results against dabigatran levels measured by Boehringer-Ingelheim (Ingelheim, Germany) using mass spectrometry.
  
  
  RESULTS
  Although routine monitoring is not required, measurement of plasma concentrations may be necessary in certain clinical situations. Routine coagulation assays such as the prothrombin time, activated partial thromboplastin time, and thrombin time do not reliably determine levels of dabigatran anticoagulation. Alternative assays, when calibrated with a dabigatran standard, such as the modified dilute thrombin time, ecarin clotting time, and ecarin chromogenic assay, may be appropriate, although a comparison of these methods using samples from patients taking dabigatran has not been performed.
  
  
  CONCLUSIONS
  Although results using all methods in this study demonstrate adequate correlation, measured dabigatran levels varied in a statistically significant manner, even when the same method was used by different laboratories. The clinical significance of this variation in dabigatran concentrations is uncertain.
authors.affiliation: 8490 Upland Dr, Suite 100, Englewood, CO 80112-7116.
authors.forename: Robert
authors.initials: R
authors.lastname: Gosselin
authors.forename: Emily
authors.initials: E
authors.lastname: Hawes
authors.forename: Stephan
authors.initials: S
authors.lastname: Moll
authors.forename: Dorothy
authors.initials: D
authors.lastname: Adcock
mesh_terms: D001562:Benzimidazoles / Q000097:blood*; D001774:Blood Chemical Analysis / Q000379:methods; D000069604:Dabigatran; D005343:Fibrinolytic Agents / Q000097:blood*; D006801:Humans; D007753:Laboratories / Q000592:standards*; D059021:Laboratory Proficiency Testing; D013058:Mass Spectrometry; D015091:beta-Alanine / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D001562:Benzimidazoles; D005343:Fibrinolytic Agents; D015091:beta-Alanine; D000069604:Dabigatran
keywords: Dabigatran; Dilute thrombin time; Direct thrombin inhibitor; Ecarin chromogenic assay; Ecarin clotting time; Mass spectrophotometry