Disease specific therapeutic range based on level of anticoagulation. Refer to Coagulation nurses for appropriate reference range.
The presence of anti-phospholipid antibodies (APAs) such as Lupus antibodies (LA) can potentially lead to elevated INR values. Comparison to an APA-insensitive laboratory method is recommended if the presence of APAs is known or suspected.
Samples from patients on warfarin with an INR <1.5 or >5.0 must be sent to the laboratory for checking.
Time Limit for Additional Tests
Finger-prick samples can only be used once.
f the test result is questionable or if clinical signs and symptoms appear inconsistent with the test result, re-test with a fresh sample or confirm the result by sending a sample to the laboratory.
The test should only be carried out by a trained member of staff.