Articles: partial-thromboplastin-time.
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Clin. Appl. Thromb. Hemost. · Apr 2006
Frequency of abnormal biphasic aPTT clot waveforms in patients with underlying disorders associated with disseminated intravascular coagulation.
Abnormal biphasic waveform (BPW) patterns were previously reported when the activated partial thromboplastin time (aPTT) was performed in plasma from patients with disseminated intravascular coagulation (DIC). In this study, the prevalence of the BPW was examined in a cohort of 508 hospitalized patients with elevated fibrinogen degradation products (FDP) levels (>10 microg/mL). The presence of a BPW was automatically flagged by the MDA analyzer when the slope of the precoagulation phase in the waveform exceeded a threshold value of -0.25%T/sec. ⋯ Odds ratios were 29.9 and 19.0 for ISTH and JMWH scores, respectively (p<0.0001). The BPW showed a moderate sensitivity (59.2% for the ISTH score; 47.9% for the JMWH score), but a high specificity (95.4% for both scores). Waveform analysis of the aPTT potentially provides a practical tool in risk assessment of critical care patients, in whom development of DIC is known to worsen the prognosis.
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Randomized Controlled Trial
Correlation between the aPTT and clinical events in acute coronary syndromes treated with unfractionated heparin.
The primary objective of this study is to analyse relationship between activated partial thromboplastin time (aPTT) and clinical events in patients with unstable coronary artery disease. ⋯ The level of aPTT shows discordance with the onset of clinical events and is a weak predictor of outcomes (Tab. 2, Fig. 7, Ref 5).
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J. Thromb. Haemost. · Dec 2005
Historical ArticleTo bleed or not to bleed? Is that the question for the PTT?
The activated partial thromboplastin time (PTT) is the grandchild of the Lee-White whole blood clot time (WBCT). Both tests were developed to assist the diagnostic process for patients who exhibited features consistent with hemophilia, i.e., the pretest probability was extremely high. ⋯ The question asked of the PTT has evolved from 'why does this patient bleed?' to 'will this patient bleed?' As the PTT was never intended to answer that question, one must be careful regarding interpretation of results of that test. As many situations not related to hemorrhage are associated with perturbations of the PTT, a prolonged PTT is not strongly predictive of hemorrhage nor does a normal PTT provide shelter against hemorrhagic risk.
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Comparative Study
Overuse of prothrombin and partial thromboplastin coagulation tests in medical inpatients.
In the monitoring of anticoagulant therapy, prothrombin time (PT) is used to measure the effect of warfarin, whereas the partial thromboplastin time (PTT) measures the therapeutic effect of unfractionated heparin. Low molecular weight heparin (LMWH) does not require routine monitoring. ⋯ The review of the records of 50 medical inpatients found that PT and PTT were invariably requested together, despite a lack of indication. The 50 patients incurred a total of $2434 in unneeded costs. If representative of common clinical practice, significant cost savings may be possible. Education, computerization, and information on costs of individual tests may reduce unneeded investigations.