Heparins are widely used in hospitals as anticoagulants. Unfractionated heparin is usually monitored using APTT and thrombin time tests. Often plasma samples are not identified as containing heparin and it may be present as an unexpected contaminant. Thus the reason for prolonged APTT or KCT tests may not be apparent and laboratory diagnosis may not be simple. Laboratories may find it useful to have a simple method for confirming the presence of heparin before going on to other investigations as may be required. The HRRS can be substituted for the usual M/40 calcium chloride solution in APTT and KCT tests to virtually eliminate the effect of unfractionated heparin concentrations up to 1 u/ml in normal plasma.
Several methods are available to remove heparin including heparinase enzyme (expensive), adsorbing agents such as ECTEOLA cellulose (not so simple) and specially treated filters. Some polymers have also been widely used to neutralise heparin, however, in excess, they can interfere with contact activators used in most APTT reagents. Thus it is more reliable to add the heparin neutralising agent in the calcium chloride solution after the contact activation stage in APTTs or KCTs. The HRRS is a simple and unique product which we believe will play a regular role in routine coagulation testing. Since identifying this as a potential necessity for every coagulation lab, we are currently establishing new manufacturing to handle rapid growth.