Detection and classification of an anticoagulant using a clotting assay

A method for treating a patient suspected of having either an anti-Factor Xa or a direct thrombin inhibitor (DTI) anticoagulant at a therapeutically relevant amount or higher, the method comprising:

• a. detecting the anticoagulant by:
• i. obtaining a sample of a blood component from the patient,
• ii. performing a first viscoelastic clotting assay in the presence of a Factor Xa reagent in a first sample of a blood component from the patient to obtain a patient Factor Xa clotting measurement;
• iii. obtaining a control sample of a blood component that lacks an anticoagulant;
• iv. and performing a viscoelastic clotting assay in the presence of a Factor Xa reagent in the control sample to obtain a control Factor Xa clotting measurement;
• wherein the presence of the anti-Factor Xa anticoagulant and the presence of the DTI anticoagulant are capable of being detected;
• wherein the patient Factor Xa clotting measurement that is at least 1.25 times greater than the control Factor Xa clotting measurement indicates the presence of the anti-Factor Xa anticoagulant or the presence of the DTI anticoagulant at a therapeutically relevant amount or higher in the patient, and
• wherein the patient Factor Xa clotting measurement less than or equal to the control Factor Xa clotting measurement indicates the absence of both the anti-Factor Xa anticoagulant and the DTI anticoagulant at a therapeutically relevant amount or higher in the patient;
• and
• b. if the presence of the anti-Factor Xa anticoagulant or the presence of the DTI anticoagulant at a therapeutically relevant amount or higher in the patient is detected, classifying the anticoagulant by:
• i. obtaining a second sample of a blood component from the patient identified as having an anticoagulant at a therapeutically relevant amount or higher;
• ii. performing a second viscoelastic analysis clotting assay to obtain a patient ecarin clotting measurement;
• iii. obtaining a control sample of a blood component that lacks an anticoagulant;
• and
• iv. performing a viscoelastic clotting assay in the presence of an ecarin reagent in the control sample to obtain a control ecarin clotting measurement;
• wherein a patient ecarin clotting measurement that is at least 1.25 times greater than the control ecarin clotting measurement identifies the detected anticoagulant as the DTI anticoagulant in the patient, and wherein a patient ecarin clotting measurement less than or equal to the control ecarin clotting measurement identifies the detected anticoagulant as the anti-Factor Xa anticoagulant in the patient;
• and
• administering to the patient identified as having a DTI anticoagulant a therapeutically relevant amount of a reversal agent that reverses the DTI anticoagulant, or administering to the patient identified as having an anti-Factor Xa a therapeutically relevant amount of a reversal agent that reverses the anti-Factor Xa anticoagulant.