The Value of Capillary Thrombotest Method for the Control of Long Term Anticoagulant Therapy

Summary

The capillary form of the Thrombotest gives results similar to the venous Thrombotest technique in patients on long term phenindione and nicoumalone, and can be recommended as a reliable laboratory investigation.

The Thrombotest range of 10—30% is a much less marked reduction of coagulability than the similar range with the Quick test. The difference in the results does not appear to be due to the sensitivity of Thrombotest to other additional coagulation factors, but simply because saline dilution curves are usually employed in the Quick test.

The upper limit of the Thrombotest therapeutic range on the basis of our studies appears to be about 15%. The lower limit of safety assessed from comparison with the Quick test and by clinical experience in the control of long term treatment appears to be in the region of 5%.

^* Consultant Haematologist, Withington Hospital, Manchester 20.

^** Registrar in Pathology, Withington Hospital, Manchester 20.

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