A modified whole blood partial thromboplastin test for the assessment of heparinization.

Current methods of assessment of heparinization are either inconvenient as bedside procedures or lack correlation with the Lee-White whole blood clotting time over the therapeutic range. A new thromboplastin time (CAT time) has been developed to overcome these disadvantages by offering uniform contact activation. The test makes use of a partial thromboplastin activated by celite-adsorbed "contact factor", thus eliminating the activation phase of the activated partial thromboplastin time. Preliminary experiments suggest that this modification will be helpful in the study of "contact factor" deficiencies.