To test recommended anticoagulation measures as predictors of 180-day venous thromboembolism (VTE) recurrence, we identified all Olmsted County, MN residents with incident VTE over the 14-year period of 1984-1997, and followed each case (N 1166) forward in time for VTE recurrence. We tested the activated partial thromboplastin time (APTT), international normalized ratio (INR), and other measure...

BACKGROUND The use of low-molecular weight heparin (LMWH) during percutaneous coronary intervention (PCI) has been limited by the presumed inability to monitor its anticoagulant effect using bedside assays. OBJECTIVES This study was designed to compare the dose-response of enoxaparin, dalteparin and unfractionated heparin (UFH) on the activated clotting time (ACT), and to determine whether th...

This study was designed to examine the relationship of short activated partial thromboplastin time (aPTT) and prothrombin time (PT) to the incidence of thromboembolic events, hereditary and acquired coagulation defects associated with an increased risk of thrombosis, or cardiovascular diseases in patients undergoing renal transplantation. The prevalence of these conditions in our patients (n = ...

The aim of this study was to examine the blood coagulation profiles of ferrets and compare them with those of rats. The ferret activated partial thromboplastin time (aPTT) was slightly longer than the rat aPTT. In contrast, the ferret prothrombin time and thrombin time were profoundly shorter than the corresponding rat values. The fibrinogen level in ferret plasma was 2 times higher than that i...

The aim of this study was to evaluate the effect of venom from Naja naja karachiensis on platelet-poor plasma, activated partial thromboplastin time (aPTT), prothrombin time (PT) / international normalized ratio (INR), thrombin time (TT) and to evaluate its effect on clotting time upon storage of plasma for a specific time period with possible mechanism responsible for that. Prolongation of PT ...

Background: Variances in blood group antigen have been related with susceptibility particular to diseases. Prothrombin time [PT], measures the efficiency of extrinsic and common coagulation pathways, although Activated partial Thromboplastin [APTT] test evaluates intrinsic pathways. Objective: To explore influence groups on APTT PT among Healthy University Students different ABO groups. Materia...

BACKGROUND The safety profile of anticoagulants, which are being used with increasing frequency in pediatric populations, is not well studied. Automatic triggers built into electronic health record systems (EHR) have been shown to be an effective way to monitor for and identify medication errors. Anticoagulant-associated adverse events were examined through the use of an anticoagulant trigger p...

BACKGROUND Unfractionated heparin is used widely; however, control of the level of anticoagulation remains its greatest problem, with fewer than 35% of patients having activated partial thromboplastin times (aPTTs) within a range of 55 to 85 seconds in recent trials. METHODS AND RESULTS We developed and tested a prototype of an automated heparin control system (AutoHep) in which a computer-ba...

BACKGROUND In an effort to improve interlaboratory agreement in the monitoring of unfractionated heparin (UFH), the College of American Pathologists (CAP) recommends that the therapeutic range of the activated partial thromboplastin time (APTT) be defined in each laboratory through correlation with a direct measure of heparin activity such as the factor Xa inhibition assay. Whether and to what ...

The Clinical and Laboratory Standards Institute (CLSI) recently abandoned its recommendation for drawing a discard tube when performing a prothrombin time (PT)/international normalized ratio (INR) or an activated partial thromboplastin time (APTT). Because there is currently no evidence that a discard tube is necessary for more specialized coagulation assays, we studied the need for a discard t...