Surface Acoustic Wave-Based Microfluidic Coagulation Device for Monitoring Anticoagulant Therapy

Abstract

An universal coagulation test that reliably detects prolonged coagulation times in patients, regardless of which anticoagulant is administered, is not yet available. The authors developed a novel, miniaturized device utilizing surface acoustic waves (SAW) to detect clotting, and used it to develop a novel universal microfluidic coagulation test. Results from this assay were compared with results from standard coagulation assays to detect classical anticoagulants (unfractionated heparin, argatroban) and direct oral anticoagulants (dabigatran, rivaroxaban). The SAW-clotting time (SAW-CT) of this novel device was prolonged in a dose-dependent manner for heparin, argatroban, dabigatran, and rivaroxaban, comparable to standard assays. The authors confirmed the clinical utility of this device in a small patient population admitted to a stroke unit. Preliminary clinical data prove the suitability of the SAW-CT in patients receiving warfarin, rivaroxaban, or dabigatran. The device could be particularly useful as a point-of-care test to assess whole blood coagulation (e.g., in stroke units or in other emergency settings).

Assessing and Reversing the Effect of Direct Oral Anticoagulants on Coagulation

“…Pointof-care tests currently in development using whole blood or urine samples report results within 10 min, allowing rapid detection of the presence of a direct oral anticoagulant to determine whether reversal is needed. [27][28][29]…”

“…31 Differences in the trial designs led to different label indications, with andexanet restricted to patients with life-threatening bleeding, 13 whereas idarucizumab is also approved for use to reverse dabigatran anticoagulation before surgery. 29…”

Clinical use and laboratory testing of oral anticoagulation therapy: experience from Finland

“…For many laboratories, it is difficult to keep up 24/7 services for few requests and the distances to the nearest laboratory will increase compared with standard INR availability. While point-of-care INR and activated clotting time (ACT) have some sensitivity to rivaroxaban, the authors opine that POC testing of DOACs is unlikely to offer solutions for the near future (75-78), although POC tests specifically targeted to DOACs are emerging (79,80). It is also noteworthy, that national and local conditions will dictate the access to (e.g., special) assays to measure DOAC effects, depending on the part of the Hospital District the patients reside in.…”

The Pointy End of Point-of-Care Testing for Direct Oral Anticoagulants

“…There are several current and emerging strategies for DOAC testing, including POC. [3][4][5][6][7][8][9][10][11] However, the research group headed by Harenberg has taken a unique strategy to develop a POC for DOAC testing using urine as the biological material and a method they have called 'DOAC Dipstick'. 5 The basis for the test is that some 30 to 80% of DOACs are excreted into the urine, and that sensitive and specific tests for either anti-FIIa or anti-FXa in urine can therefore be developed.…”